Dalton Tavares 2008 Simpsonychthys и Nematolebias [PDF]

Zitiervorschau

Dalton Tavares Bressane Nielsen

Simpsonichthys and Nematolebias

Cabral Editora e Livraria Universitária 2008

Dalton Tavares Bressane Nielsen

Simpsonichthys and Nematolebias

2008

Copyright ©

Cabral

Editora e Livraria Universitária

All rights reserved, no part of this publication may be reproduced or transmitted by any means, eletronic, mechanical, photocopying or other wise, without the prior permission of the publisher.

General Director Mário Cabral de Vasconcellos Eletronic Editor André Luiz Cabral de Vasconcelos Cover André Luiz Cabral de Vasconcelos Foto: Rosário La Corte Review Karol Lotufo Translation to English (origin in Portuguese) Casa Cultura - (12) 9773.2950

Simpsonichthys and Nematolebias: Nielsen, Dalton Tavares Bressane Taubaté-SP: Cabral Editora e Livraria Universitária, 2008. 235 p.; 160 x 230mm ISBN: 978-85.7824.008-0

CDD 574 574.5 574.9

Sistematic catalog index: 1. Biology. Marine Biology.

CABRAL EDITORA E LIVRARIA UNIVERSITÁRIA Rua Quatro de março, 383 - Centro CEP 12020-270 - Taubaté - SP Fone/Fax: (12) 3624-7641 www.editoracabral.com.br e-mail: [email protected]

I dedicate this book to my wife Norma Aparecida Prado dos Santos Nielsen that knew how to be patience on the moments which I was absent to elaborate the book, for research trips in field and for understanding this passion that makes me to devote good part of my time to study and understand about this wonderful universe of the annual fish To my father, Ivan Bressane Nielsen and my mother Clotilde Tavares Nielsen, for their motivation on this my vocation.

Acknowledgments

Thanks to all my friends: André Carletto, Didier Pillet, Rogério Suzart, Maurice Chauche, Francisco Falcon, Julio Ghisolfi, Steffen Hellner, Roger Brousseau, Dr. Wayne Leibel, B.E.Kynard, Danilo Paiva, Marcos Almeida, Ruud Wildekamp, Valdesalici Stefano, Gustavo Grandjjean, Gilson Gil Mauro, Dan Katz e Rosário La Corte, for their help on the research and elaboration of this book, with information, photos and field trips, for without them it would not have been possible to undertake this project. Special thanks to a great friend who is no longer with us today, but who taught me much regarding the breeding of ornamental fish and who contributed during many years to the development of the hobby, Edson Lopes.

Presentation Back in 1993 I was invited by my friend Dalton Nielsen to join him on a collecting trip. I’ve had the opportunity to collect some killies1 before, but they were very conservative, without planning or too much ambition. The trip of 1993 would be different. We would follow a Dutch biologist, Rudd Wildekamp, and an American hobbyist, Dale Weber. We had the clear objective of finding several known killies species in the Southwest and Midwest of Brazil and, with some luck, find some new species. After a difficult start (several bone dry localities and mainly the realization that the relationship with our ‘partners’ wouldn’t be easy) we crossed the town of São Francisco, at the banks of the river with the same name. In the town outskirts we found a pool that looked perfect: clear, shallow water and lots of aquatic vegetation. Given our growing frustration, only Wildekamp decided to give it a try. Not even stepping into the pool, he scooped the water with a long shaft dip net. Fish! He shouted. He has just collected two females of an annual killie. Quickly, we all jumped into the pool in an attempt to collect at least one male, in order to identify the species the fish belonged to. On my first attempt, my net brought a fish I’ve never seen before: about 2 inches long, with the body banded in blue and purple and long extension in the dorsal and anal fins. I got it! I got it! - I screamed. Everyone came running and after a few moments we all got to the same conclusion: it was a new species. We looked like a bunch of kids, jumping and screaming inside a side-road ditch. 1 Killies: Killifish plural. Group of small size fish with cylindrical shape, colorful and ovíparus, from Cyprinodontiformes order. It’s etimology cames from de Dutch, that means fish canal. At the end of XVIII century, the word started to appear with order grafic writtens: Killyfish, Killefish, Kill fish, Killeyfish, Killiefish before Kiillifish.

The emotion of collecting such a beautiful fish, knowing it was a new species, was so profound that on the next day Dalton confessed that, just like me, he also had dreamed with the fish in the night after we collect it. A few months after the event, we discovered that the same fish had been collected by Steffen Helner a few weeks before us and it was being described as Simpsonichthys. But that didn’t change the magic moment we had in the banks of the São Francisco river. Our expedition ended after running more than 3.000 milles on an old Volkswagen van, trough the three major hydrographic basins in Brazil (São Francisco, Araguaia and Paraná) and found the most incredible fish. Many other collecting trips followed this one on 1993. Even then, my heart beat still goes up every time I get one of these fantastic fish. I hope everyone reading this book feels at least part of the emotion of finding this fascinating little fish, without having to face the loads of mosquitoes, leeches, roach infested hotels, stinky wet clothes and long, long hours driving trough the horrible secondary roads in Brazil.

Good reading! ANDRÉ CARLETTO

Contents Simpsonichthys and Nematolebias South American annual fish Introduction ................................................................................... 1 - History ...................................................................................... 2 - Morphology .............................................................................. 3 - Feeding ...................................................................................... 4 - Reproductive behavior ............................................................. 5 - Reproduction in aquarium ........................................................ 6 - Sicknesses ................................................................................ 7 - Systematic ................................................................................. 8 - Geographic distribution ............................................................ 9 - Ecology ..................................................................................... 10 - Subgenera: Simpsonichthys ........................................................ - S.boitonei .............................................................................. - S.cholopteryx ....................................................................... - S.nigromaculatus ................................................................... - S.parallellus ......................................................................... - S.punctulatus ....................................................................... - S.santanae ............................................................................. - S.zonatus .............................................................................. 11 - Subgenera Hypsolebias ........................................................... - Group S.antenori ................................................................ - S.antenori ........................................................................... - S.flagellatus ......................................................................... - S.flavicaudatus ................................................................... - S.ghisolfii ............................................................................. - S.igneus ............................................................................... - S.janaubensis ......................................................................... - S.macaubensis ..................................................................... - S.mediopapillatus ...................................................................

15 19 21 25 29 42 51 53 61 67 89 90 94 96 99 103 106 108 111 112 113 115 117 119 121 122 124 126

- Group S.flammeus .............................................................. - S.alternatus ......................................................................... - S.brunoi .............................................................................. - S.delucai ............................................................................... - S.fasciatus ......................................................................... - S.flammeus .......................................................................... - S.marginatus ....................................................................... - S.multiradiatus ................................................................... - Group S.magnificus ............................................................... - S.adornatus ......................................................................... - S.carlettoi .......................................................................... - S.fulminantis ......................................................................... - S.hellneri .............................................................................. - S.magnificus ........................................................................... - S.picturatus ........................................................................ - Group S.notatus .................................................................... - S.auratus ................................................................................ - S.gibberatus ........................................................................ - S.nielseni ........................................................................... - S.notatus ............................................................................ - S.ocellatus .............................................................................. - S.radiosus ............................................................................ - S.rufus ................................................................................ - S.similis ................................................................................ - S.stellatus ............................................................................. - S.trilineatus .......................................................................... - S.virgulatus .......................................................................... 12 - Subgenera Ophtalmolebias .................................................... - S.bokermanni ..................................................................... - S.constanciae ...................................................................... - S.perpendicularis ................................................................ - S.rosaceus ........................................................................... - S.suzarti .............................................................................. 13 - Subgenera Spectrolebias ...........................................................

127 128 130 132 134 136 138 140 142 144 146 152 154 156 161 163 164 167 169 172 174 176 178 180 182 184 186 189 190 192 194 196 198

- S.chacoensis ..................................................................... - S.costai ............................................................................. - S.filamentosus .................................................................... - S.reticulatus ....................................................................... - S.semiocellatus .................................................................... 14 - Subgenera Xenurolebias ........................................................ - S.izecksohni ........................................................................ - S.myersi .............................................................................. 15 - Genera Nematolebias .............................................................. - N.papilliferus ..................................................................... - N.whitei ............................................................................... Conclusion ..................................................................................... References .......................................................................................

201 202 204 207 209 213 219 220 222 225 226 228 231 233

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Introduction “How can a simple rain water pool get filled up with fish right after the start of the rainy season?” What a strange fish is this that, as if by magic, ‘show up’ in a water pool that was totally dry for so long? There can be many scientific explanations for this fascinating fact, but for the local people that had witnessed this phenomenon, these will always be the ‘Cloud Fish’ that simply fell from the sky along with the rain drops

The species of Simpsonichthys, Carvalho 1959, and Nematolebias, Myers 1942, are truly unique kind of fish, the males presents flamboyant that rival only marine reef fish. Their reproducible behavior is an incredible example of adaptation which allows them to occupy ecological niches impossible for other fish species. The Simpsonichthys and Nematolebias capacity of adaptation to their environment is so impressive that is hard to believe that a fish can live on a completly dry environment for so long. How can they survive to such harsh conditions? That´s why these little fish, commonly called ‘Cloud Fish’ by local people in Brazil, developed a unique reproductive behavior in order to live in those inhospitable environments. The Simpsonichthys and Nematolebias live in temporary water pools, where they lay eggs by diving into the substrate. At the end of the rainy season the pool dries and all fish die, but their eggs survive and develop throughout the dry season, waiting for the next rainy season. As soon as the rain starts, the pools fill up with water and the eggs hatch, starting a new generation that will have their turn to grow, breed and keep the cycle going.

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Very popular among aquarium hobbyists all over the world, many species are maintained in tanks for many generations without too many changes or genetic variation, all over the world. Most of the Simpsonichthys and Nematolebias have a pretty pacific behavior towards other species, but males normally define breeding territories which they defend by flashing their colors and displaying at the boundaries of their territories. The Simpsonichthys and Nematolebias are part of a group of fish known as Killifish. Killifish is a common designation for all egg laying fish of the Cyprinodontiformes order. The Simpsonichthys are part of the Rivulidae which is in turn included in the Cyprinodontiformes order. The origin of the Cyprinodontiformes goes back 200 million years. Back then, a single dry land mass, formed by a ‘super continent’ called Pangea, was starting to divide in two. The mass to the North was called Laurasia, and the one to the south, Godwana. Between those two new continents a shallow sea was formed, called the Thetys Sea, and that’s where most of the bony fish, including the Cyprinodontiformes, first appeared. There are many other genera in the Rivulidae family that have a similar reproductive cycle as the Simpsonichthys and Nematolebias; they are called ‘annual fish’ due to their annual life cycle. In some habitats, the Simpsonichthys are found in sympatry, living together, with some other species. Many times, larger predatorial annual species, like the Cynolebias, are found along with the Simpsonichthys. Despite the fact of being the South American annual genera with the most number of species, only recently most of them were discovered and described by researchers. All of them were described after the middle 80’s, with a ‘flooding’ of new species being described from the 90’s until today. Most of them were discovered in the São Francisco basin, where 75% of the species of Simpsonichthys are from (Costa 2003). Beside the beautiful coloration of the males, many species have exquisite fineage, with extensions in the dorsal and caudal fins. The intense color seems to be an evolutive adaptation related to sexual selection, where the most brightly colored males are normally the healthier ones and because of that, the most attractive for

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females. Despite the fact that their intense color could make them also very attractive to predators, most of them live in such inhospitable habitats that they rarely have any predators. There are only two species of Simpsonichthys not found in Brazilian territory: S.filamentosus and S.chacoensis, but this is probably due the fact that very few research expeditions have targeted countries like Bolivia and Paraguay. With all these attributes, the Simpsonichthys and Nematolebias are one of the most fascinating ornamental fish to be maintained in tanks. The fact their eggs can be exchanged by mail certainly contributes to the increasing number of species maintained by hobbyists. Clubs and associations specialized in maintaining and breeding Killifish are present all over the world, especially in Europe, USA and Asia. One of the main objectives of this book is to present, in detail, the elaborate reproductive behavior and fascinating ecology of the Simpsonichthys. A technical file was created for each currently known species containing information about Description, Etymology, History, Breeding, Habitat and Distribution.

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History In april 1959, Brasília’s construction was a few weeks away from it completion. At the place where the zoo was being built, a zoo keeper was collecting fish in the nearby ponds to feed the birds. In a small pool at the banks of the Riacho Fundo River, a small fish with a red color, dotted with iridescent blue spots caught the attention of the zoo worker who took it to his boss: José Boitone. A few weeks after, Mr Boitone sent 7 specimens to the biologist Antenor Leitão de Carvalho who thought they were similar with fish from the Cynolebias genus. He soon realized those fish didn’t have pelvic fins, a characteristic only present, among Cyprinodontiformes, on fish of the Orestias genus, a group of fish from the Chilean, Bolivian and Peruvian Andes. Due to this uniqueness, Dr Atenor de Carvalho described this fish as belonging to a new genus, in the “Boletim do Museu Nacional do Rio de JaneiroBrasil, Zoologia nº 201, May 11th 1959”: “New genus and species of annual fish in Brasilia” The justification of this new genus creation, transcription of classification work. Simpsonichthys new gen. Type species: Simpsonichthys boitonei sp n Simpsonichthys is a member of the Rivulini tribe, but without pelvic fins. With an elongated body, its biggest body height fits four and half time its total length. The males have their dorsal fins planted right above the anal fin’s origin and

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its base is longer than the last’s. On females, the length of the dorsal fin’s base is smaller than the anal’s and its origin is posterior than the last. The male’s pectoral fins have long median rays reaching the 4th ray of the anal fin; the female’s fins are shorter, not reaching the urogenital spot. Females have dark vertical bars and spots on their sides, like those of the Cynolebias females. Round caudal fins. Normal caudal peduncule, without narrowing on its lower side. Narrow preorbital, parietals present, pseudo-gills present, and pelvic fins absent. Few slender and conical teeth present in the center forward portion of the vomer. Movable premaxilary. Teeth in the dentary and premaxilary relatively large. (1) New genus named after my friend Sr. Charles J. Simpson, San Francisco CAUS and the species named after Mr. José Boitone. Since then, a new group of fish caught the attention of several hobbyists and Ichthyologists around the world, with their beautiful colors and unique shapes. Actually, the first known species of Simpsonichthys was S.constanciae, since it was first collected in 1941 and described one year later. But, back then it was placed in the Cynolebias genus, being reclassified as Simpsonichthys only in 1996. Since the 80s, field research and collecting trips got more frequent and many new species were discovered, making this genus the one with most species in the Cynolebiatinae sub-family Today are know 2 species of Nematolebias and 51 species of Simpsonichthys, divided in 5 sub-genus, and present in tanks all over the world.

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Morphology The Simpsonichthys are very easy to identify. Males are normally very colorful, while females have a much subdued coloration ranging from brown to grey with spots or dots over their bodies. They are small fish with size varying from 20mm to 70mm. Some species do not have pelvic fins, which caused the new genera to be created. In many species, the males have extended anal and dorsal fin rays, giving them an exquisite shape. The eyes possess a dark traverse strip. The Simpsonichthys present line of Neuromasts on their heads. These neuromasts are directly connected with their lateral lines, an organ that helps fish feel their surroundings by detecting small variation in the water pressure.

Neuromasts

Draw: Dalton Nielsen

Draw: André Carletto

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Neuromasts

Scale

Many of the most distinctive characteristics on Simpsonichthys can only be observed by microscope. Nowadays, whenever a new species is described, more than 100 morphological and anatomical characteristics are analyzed. In this chapter we’ll see the most relevant and interesting ones. Size: As mentioned before, the Simpsonichthys are small fish with a size ranging from 20mm to 70mm. The smallest ones are S.costai, S.reticulates, S.parallelus and S.cholopteryx, which are known to be the smallest species in the Rivulidae family (Costa, 2006). The largest Simpsonichthys are part of the Hypsolebias sub-genus, where S.alternatus and S.ghisolfii can reach more than 70mm. Some Nematolebias can reach over than 85mm. In all Simpsonichthys and Nematolebias species, the males are bigger than females, which are, on average, 20% to 25% smaller. On S.ocellatus, females have only 65% of the male’s body length (Costa, 2006). Body shape: The Simpsonichthys have higher body shape than Nematolebias, which has a more elongated, slenderer body (Costa, 2006). Urogenital papilla:

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The male Simpsonichthys have a tubular, slightly protruding urogenital papilla. Females have a flat, hard to see papilla, located right in front of the anal fin.

NP- Pelvic fin; NA Anal fin ; PU Urogenital papilla.

Color: Color is an extremely important characteristic on Simpsonichthys, since it makes evident an elaborate process of sexual selection among them, where the male needs to show its colorful best possible through the moviments. The color varies not only from green to red, blue and yellow, but the color patterns are also extremely variable, from spots to vertical and horizontal bars. (BELOTE e COSTA, 2002) Fins: Another extremely import characteristic of Simpsonichthys males, with reproductive purpose, are pelvic fins. Several species show unusual shapes and long extensions, as mentioned before, some species (S.boitonei, S.parallellus e S.cholopteryx) do not have pelvic fins, that the reason for the genre Simpsonichthy has been created. Tactile Papillae: Right before diving into the substrate to lay eggs, females touch the male’s

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pectoral fins with their heads, signaling it to dive. The male’s pectoral fins have tactile organs, called tactile papillae, which helps the male to feel the female’s position, indicating when and to what direction it should dive. It is also possible that the tactile papillae can help males to identify a female from its own species. In many pools in the São Francisco basin the water is murky due to the clay composition of its bottom, making tactile sensing more important than visual. The tactile papillae also seem to be related with sexual maturity, since they are more prominent in young males (Carvalho, 1957)

tactile papillae

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Feeding Simpsonichthys are omnivorous fish, despite their predatorial nature and carnívorous feeding, specially insect larvae. Stomach content analysis showed up to 85% of Quironomidae larvae, know as “blood worms” by aquarists, on some fish intestinal tracts. When we analyse, we not that the Simpsonichthys mouth faces upwards, indicating an adaptation to capture insect larvae. The Simpsonichthys have an extremely high metabolic rate since, in nature, they have very a short time window to grow and reproduce. This makes a balanced and quality diet extremely important in breeding this fish in captivity. Feeding fish like S.constanciae and N.whitei, with blood worms can significantly improve their egg production. Their preference for insect larvae has a strong relationship with their environment. What better place to find insect larvae than temporary pools in lowlands? It is even possible that these fish colonize seasonal pools due to the amount of food available in these habitats. During my 22 years collecting killies, I’ve never found a single fish that wasn’t well fed. Even fish heavily parasitized by nematodes didn’t show signs of malnutrition. As in other fishes, the Simpsonichthys are exothermic or “cold blood” animals: their body temperature is regulated by the temperature in their environment. Because of that, the amount they eat and how efficiently they absorb nutrients, depends on their environment’s temperature. This makes very important to know what are the original conditions of different species in their natural habitat, so we can try and reproduce them in captivity. Despite the fact the water temperature varies during the day and throughout

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the year, most Simpsonichthys are found in water ranging from 20ºC to 24ºC. The southern most species are S.constanciae, found at latitude 22º43’S, and N.papilliferus, 22º 55’S, latitudes at which the climate is still predominantly tropical. At the beginning of the dry season, when the water of temporary pools start to dry out, the temperature goes trough a significant changes, reaching up to 36ºC. In these conditions, the high water temperature causes the amount of dissolved oxygen in the water to drop, significantly reducing the fish’s capacity to absorb. Tubifex, Artemia salina, Daphina, fruit fly and white worms are other sources of food that are readily accepted by adult Simpsonichthys. Eventually, Simpsonichthys can take industrialize dor flake food, but the process of getting them used to it takes time and requires the hobbyist to be patient. The switch to flake food should be done in a progressive manner, slowly replacing the amount of live food. This process is very important for people who do not have direct access to sources of live food. Home recipes, like paste food, also work well. But, the fish also have to be ‘trained’ to get them. Patience is very important. It is much easier to get fish used to non-live food when they’re young. The Simpsonichthys fry will easily take Baby Brine Shrimp, micro-worms, decapsulated Brine Shrimp eggs and vinegar eels, with Baby brine Shrimp being the most nutritious and well accepted food. Baby Brine Shrimp should be separated from the egg’s shell after hatching and the nauplii should be rinsed with clean fresh water, to remove the excess of salt, before offering them to the fry. Micro-worms, decapsulated Brine Shrimp eggs do not require any special attention, but it is extremely important to not offer any source of food in excess, since it can cause a significant increase in nitrogenous compounds in the water. It is extremely important to carefully wash vinegar eels before offering them to the fry, otherwise the vinegar they live in can quickly drop the water’s pH, which might kill the young fish. Offering food twice a day (early in the morning and early in the evening), in small quantities, is the ideal. Food should be offered in quantity enough to be consumed in no more than 5 minutes. Food not eaten after 5 minutes should be

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removed from the tank in order to keep the water clean and in the ideal conditions for the Simpsonichthys optimal food conversion. The hobbyist sensibility is really important and BALANCE is a key word in a successful feeding strategy.

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Breeding Behavior The fact that Simpsonichthys live in temporary water pools has rendered possible the subsequent development of an elaborate and interesting breeding behavior. The popularity of this group of fishes among aquarists is much due to this outcome. The breeding behavior of the Simpsonichthys appears to follow a defined pattern, with only small differences among the species. These patterns aid in the study and definition of an evolutionary proposal and so are useful for systematic analyses. This form of inquiry is denominated compared etiology by science, and is based on the ideas of Charles Darwin (1859), in which instinct evolves, and so ensuing behavioral patterns may be used as indicators of a common lineage (Belote, 2000). In 1957, Antenor Leitão de Carvalho wrote a scientific paper, published in the Brazilian Journal of Biology, in which he conveyed information on the biology of N.whitei, in the locality of São Pedro da Aldeia, in the state of Rio de Janeiro, with references to the biotype and its breeding behavior, apart from describing the spawning conduct of the fish, as outlined below. After the fishes had become accustomed to the aquarium, the male started to inspect the substratum therein, in this followed by the female. She, in turn, initiated movements around the male, to an extent that they began to match forces. As result of all this movement, the water became progressively muddier, thus making it impossible to observe the spawning procedure. Therefore, the turf substratum was exchanged for fine and well-washed beach-sand. Only then was it possible to contemplate the spawning process. The male, swimming close to the bottom, began the inspection, with the female close behind. (Fig.l). Sometimes, he would suddenly stop, make a rapid up-and-down movement with the body as if nodding his head, and afterwards

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continue the inspection. The female, swimming first to the left then to the right, would occasionally touch the anal fin of the male with her mouth. On finding the appropriate place, he then placed himself head-down in an oblique position, approximately 30º from the vertical. The female then came forward and placed her head between the body and the pectoral fin of the male, putting the end of her nose on his axil (Fig. 2), whereupon both, with a quick and flagellate-like conjugated movement of the tail, penetrated into the substratum. Immediately following this plunge, both laid down sideways inside the sediment, thereby beginning a rotation movement of the body. This was the moment in which the egg was expelled and fertilized, the female always remaining below and completely buried (Fig. 3).They would stay in this position for 3 to 4 seconds, to afterwards come back to the normal position (Fig.4). The substratum, which was displaced by the couple on diving, then fell onto the egg, thus burying it (Carvalho, 1959).

1

2

3 4

An illustrative drawing, compiled from the work of Antenor Leitão de Carvalho, 1957.

Spawning continued with intermediate pauses for several days. The time between consecutive dives was approximately five minutes. The cleared-colored and transparent eggs, like minute gelatin pearls, were small and measured 1,25mm in diameter. On entering in contact with the substratum, they became enwrapped by a certain amount of matter, this sticking to the egg. On observing the eggs through the microscope, the surface of the chorion

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reveals small regular spicules of two sizes, the smaller ones being distributed in the interval between the bigger ones (Fig. 6). The vitellin mass (yolk) is clear and transparent like the chorion. There are 5 small drops of oil of different sizes which remain on the upper surface of the egg (Fig.7).

m

1mm

3m

7

5

0,2mm

6

Illustrative drawing compiled from the work of

8

Antenor Leitão de Carvalho, 1957.

Photo: André Carletto. Spicules on the surfaces of eggs.

One of the most intriguing aspects of breeding behavior was the fact that the female placed her head between the pectoral fin and the body of the male, shortly before diving.

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The male was examined in detail and it was noted that there were tactile papillae (Fig.8) on the inner side of the pectoral fin, on the first eight rays counting from top to bottom. The function of these is to indicate to the male both that the female is ready for the plunge and whether she is more to the left or to the right. Over the last few years, with the increase in publications, especially by internet, a greater exchange of information was made possible, both as regards this topic, as well as on the development of knowledge on the breeding of annual fishes. On most occasions, information was mainly obtained by aquarists, and referred to the physical and chemical conditions of water, the time necessary for incubating eggs, methods for raising fry, problems with sexual disproportion among fry, the different types of substratum and alternative methods of embryo formation from eggs, all of which were related to captive breeding and with the aim of keeping the species in aquariums and, consequently, of being able to exchange the surplus raised for other species. Until publication of the present work, aquarists were those who had the most available information on breeding behavior at their disposal. Even nowadays, the contribution by aquarists on this topic is very important, for in several aquariums spread around the world, various experiences are undertaken, the love of the hobby leading several people to become researchers, even though for only a few moments and in an empirical way. Basically, the breeding behavior of annual fishes was always described in a simple manner, this until the publication of the Master’s Thesis of Belote, Drausio de Freitas in 2000: A Study of the Evolution of Breeding Behavior in Cynolebiatini. ... and in 2001: Reproductive Behavior Patterns in the Neotropical Annual Fish Genus Simpsonichthys, Carvalho 1959 (Ciprinodontiformes, Rivulidae) Description and Phylogenetic Implication. Breeding behavior has been divided into 5 distinct phases (Belote, 2000). 1- “Courtship display”: After inducing a meeting, the male begins courtship display with waving motions of the body, while moving around and in front of the female, for about ten minutes on an average. In most

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species, the coloring of the males becomes more intense, while during display their single fins remain expanded. Nevertheless, in fishes of the S.boitonei group, during male courtship, single fins assume another format, as these are closed instead of expanded, the latter being the case of the remaining species.If females are receptive, they follow the males. On the contrary they move away (Belote, 2000).

2- “Invitation to submerge”: The male places its nose in the region in the substratum where it wishes to dig. On inclining its body at an angle varying between 30º and 90º in relation to the substratum, he invites the female to couple by quivering the body and fins. (Belote, 2000).

3- Submersion into the substratum: The female accepts the invitation and sidles alongside the male, whereupon both dig into the substratum with waving vibrations of the body (Belote, 2000).

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4- Spawning/Fertilization: They submerge into the substratum, where the female lays an egg. At that exact moment, the male presses the female against the substratum with his body and fertilizes it. When there is no substratum, it was noted that the male, with closed single fins, slowly laid himself upon the female and, with quivering body, squeezed her. At the same time the female expelled the egg which was immediately fertilized by the male. Once over and with a little more effort, the male moves away from the female (Belote, 2000).

5- Emergence (back from the substratum): After fecundation, the couple remains submerged for some seconds to a few minutes, emerging together or not, perchance at different places and times (Belote, 2000).

The dispute for territory between males, in some species such as N.whitei, can be so violent that ends on a death of the beaten oponent. This aggressive behavior can be directed against females, although this happens more rarely. In nature, the loser withdraws from the strife, so as to avoid further attacks and preserve himself. Smaller and weaker males are paler in color than dominant ones, thus indicating submission to the “alpha male”. In an experiment undertaken with 5 males and 8 females of S.magnificus, in a 50 liters aquarium, it became clear that the use of display was not only to

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attract the female but also to defend the territory, and so demonstrate its virility to any possible opponent. A male, on perceiving another near to its territory, would begin its exhibition through the expansion of all single-fins and by enhancing colors. On approaching the rival, this would also repeat the same procedure in the case of confront, or withdraw in the case of renouncing. After the first display, the male looks for a female, which he forces through the procedure of spawning, to then, immediately after the act, go back to facing his opponent, as if wishing to demonstrate his virility to the rival. Females do not mark territories, but only wander randomly through those of the males. The territories of these are generally little defined, being approximately 5cm in diameter around each individual, this changing place as they move around. In 2006, Shibatta split the behavior of S.boitonei into breeding and agonistic. Agonistic behavior is more frequent among males, but can also occur between males and females and among females themselves, but with less frequency. In males this behavior is related to territory, whereby they enhance colors and expand fins, as occurs in breeding behavior. After display there can be dispute or flight of one of the opponents. The description is very much like that observed with S.magnificus. The chorion of the egg is very rigid and difficult to crush with the fingers. This is probably so to avoid dehydration of the egg, although, apart from this rigid chorion, there is exchange of gases between the egg and its environment. Aggressiveness among males is very variable in different species, and there can be variations within the same species, for different items such as food and the dispute for territories or females.

Photo: Male of S.fulminantis on “display”

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Simpsonichthys and Nematolebias

Diapause: The eggs of annual fishes possess a mechanism for the control of embryo development called the DIAPAUSE. This mechanism allows the species to survive the innumerous climatic variations that can occur during the year or during the most prolonged cycles. The diapause consists of an almost total interruption of metabolism and, consequently, development of the embryo. The latter, in the meantime, continues to sporadically emit metabolic signals. This process is essential for the survival of annual fishes in their seasonal environments (Wourns, 1976). This mechanism is very important for avoiding that Simpsonichthys and other annual killifish eggs hatch at the wrong time. What would happen to an entire generation if there were a heavy rain out of the season, thus filling the pool for a short period? Eggs would hatch and there would not be time enough for the fishes to grow and breed again. In the present case, nature found a way to leave the embryo in a dormant state, to hatch only in the rainy season itself. Environmental, physical and chemical factors are responsible for the speed of embryo development, and for activation and disactivation of the diapause process. Environmental Factors: The populational density of adult fishes and their exposal to the photoperiod have an influence on hormone secretion. Physical Factors: Temperature, pressure of the water column, moisture of the substratum, photoperiod and substratum granulation. Chemical Factors: Ammonia concentration, oxygen and carbonic gas availability. Therefore, it is very difficult to define the incubation period of an egg, for this depends on a combination of all these factors, and which vary in each environment. It is common in nature for us to find nearby pools in different stages of population growth. In an experiment, it was noted that eggs coming from the same clutch and kept in identical physical and chemical conditions, can present different stages of development. This could represent another strategy among annual fish species so as not to run the risk of an entire generation being born at a certain period without finding favorable conditions to grow and breed, as for example some year in which

Simpsonichthys and Nematolebias

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the rains are of short duration, thus not permitting that generation to complete its cycle. Some eggs can adjourn, awaiting one cycle more to develop. There are reports of viable eggs more than six years old. The presence of the Diapause suggests an alteration in morphology and physiology in the developing embryo of annual fishes in relation to other osseous fishes. The physiological alteration changes the control in the developmental mechanism, thus either permitting a continuous development of the eggs (escape eggs) or then, their passage through a prolonged period (Wourns, 1976). The diapause in annual fishes is similar to that which occurs in insects. In the latter, both occurrence and intensity are submitted to genetic control. The variation in duration in which the eggs remain in the diverse diapauses suggests that this deviation is genetically determined, and that it could correspond to the background of regularity in the rainfall of the species habitat. A characteristic of the Diapause is its extreme variability in incidence and intensity. Some species of Simpsonichthys inhabit very arid regions in the Brazilian northeast, whereas others reside in extremely humid regions, such as the Atlantic Rain Forest and the Amazonian Forest, as well as intermediary regions as, for example, the Brazilian cerrado. The Diapause can appear in three stages during embryo development in annual fishes. These stages are known as Diapause I, Diapause II and Diapause III. Diapause I occurs in the cell-disappearance phase, Diapause II in the somiteforming phase and Diapause III in the pré-hatching phase.

Drawing by Dr. Wayne Leibel, 1982.

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In 1976, Wourns identified and described 46 steps in the development of embryos in annual fish eggs, and presented the differences in embryo development between annual fishes and the remaining teleosteons. There are two great differences in embryo development between annual fishes and common teleosteons: 1- The existence of the Diapause. 2- In the first stages of embryo development, more specifically in stage 12, there is a division of the cell mass, which is called the blastula, into two cell populations. One population will form the embryo while the other will form an extra embryo layer which breaks up at the time of hatching, and which is possibly necessary to aid the egg in passing through the dry phase. In the Wours (1976) experiment, the eggs were kept in water at a temperature of 25ºC, with a variation of 2ºC. Under these conditions, most of them do not enter into Diapause I, unless they undergo environmental stress, such as the absence of O2 or a drop in temperature. They normally enter into Diapause II and the majority, around 95%, into Diapause III.

Annual fishes are the only vertebrates with embryo development that permits having yearly eggs (Wours, 1976). These fishes can only maintain their populations in temporary habitats, in so far as their eggs survive dry periods through the Diapause mechanisms. The species subsists notwithstanding irregular environmental cycles and ecological catastrophes. The eggs of annual fishes can be induced to develop with or without the Diapause. It is only necessary to control physical and chemical conditions during the period of embryo development. In order to do this it is very important to know the origin of the species. The survival strategy is based on the so-called “multiple effects” derived from the three Diapauses. The multiple effects originate from the sub-population of eggs, giving rise to eight different ways for embryo development to go ahead. One sole population of eggs of the same age may generate various sub-populations, each one with different forms of development. The “multi-effect” principle increases the chances of survival of the species, with the guarantee that eggs hatch in the best period for the growth of fry (Wourms, 1976).

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A Stage 20 of embryo development. B Stage 33 of embryo development. C Stage 43 of embryo development. DI Diapause I D II Diapause II DIII Diapause III d1 to d8 Options for embryo development. d1 Option for development over a longer period. d8 Option for development over a shorter period, whereby the embryo does not pass through any diapause, the so-called “escape eggs”. These ways concede ample flexibility to make use of opportunities for hatching in different periods. Thus, the same batch of eggs can be ready to hatch in 40 and 240 days. Around 10% develop in 40 days, these constituting the so-called “escape eggs”. These are eggs that did not pass through any diapause, thus going through uninterrupted development. On the other hand, those eggs that took 240 days (8 months) passed through the 3 diapauses, and there is still a series of intermediary combinations (according to the above drawing represented by the letters d1 to d8), which allow

40

Simpsonichthys and Nematolebias

for development in 40 to 240 days, keeping the eggs at a temperature of 25ºC and incubation in water. In the natural habitat, there are many risks against survival, characterized by the non-conjectural status of rainfall regimes. In order to face these conditions, annual fishes have adopted the strategy of multiple effects, which furnishes survival in the chaotic climate to which they are submitted. Thus, in the case of any extreme situation, such as those described above, there will be eggs in conditions to hatch and so perpetuate the species. Consequently, in the same batch of eggs we can encounter eggs in the four different stages of development: Direct development, Diapause I, Diapause II and Diapause III. This adaptive strategy is necessary for the diverse environmental conditions to which they are submitted. Even though some of these conditions are contrary, such as excessive rain and drought, the survival strategy can be identical, the egg remaining in the state of Diapause until such a time when environmental conditions return to the ideal. The occurrences EL Nino and La Nina are cyclic meteorological phenomena, with variable intensity and which have an influence on rainfall indexes by adding accumulative effects in the form of successive floods and droughts, thus altering the seasonal regime of pools to which many species of annual fishes are adapted. List of embryonic development of South American annual fishes with their respective micro-climates. 1. Pool in a regular state: Regular development of annual fish embryos. 2. Rainy year: In this case, predation of annual fishes may occur, this brought about by other species of fish that invade the annual pools, but as not all the eggs hatch, many remain in Diapause I and II awaiting the following year. When there is no invasion by predatory fish and the pool can connect with a river, the annual fishes use this means to disperse the species. 3. Dry years: Eggs can remain in stages Diapause I, Diapause II or Diapausa III, awaiting better environmental conditions. 4. Subsequent years with much rain: The same may happen as in item 2, only that when the cycle is re-established there will be fishes originating

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41

from eggs that stayed in Diapause over a long period. 5. Subsequent years with drought: Eggs remain in Diapause within a humid layer of the substratum. Even in years of prolonged drought, there is a little rain, which together with the vegetation of underground water, keeps the soil moist. Eggs in this situation are more common in Cynolebias species, which dive deeply into the pool substratum to spawn. 6. Year of irregular rainfall: Once again, some eggs remaining in Diapause to afterwards hatch in succeeding years, is essential for the survival of annual fishes. 7. Indian Summer: In this case we can observe rapid development of the embryo. The pool might not dry up totally during the Indian Summer. This being so, eggs undergo direct development without Diapause. On the other hand, the pool may dry up and so eggs proceed to Diapause III, awaiting the quick return of rain.

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Simpsonichthys and Nematolebias

Reproduction in Aquarium This is one of the most exciting chapters for the ornamental fish breeder. Herein, we will take a look at the various techniques used by aquarists to breed the diverse species of Simpsonichthys in captivity. Each aquarist develops his own methodology for breeding Simpsonichthys; hence the techniques described on the book do not eliminate others. Some of them work very well for one breeder whilst they may not be ideal for others. The first step is when choosing matrixes. The ideal is to have two or more females for each male, as the energetic expenditure of the former is higher than that of the latter, and so there is a greater tendency to fatigue. In the event of the breeder possessing a couple, after two days of spawning, it would be advisable to separate them for two days, in order to the female may recuperate herself, to then pass to a shift system: two days breeding followed by two days resting. When separating, it is not convenient to leave them where they can see one another, as this could stimulate the female to spawn without the male. It is also propitious to observe the sizes of the fishes. It is best to choose fishes of about the same size. Place the substratum on the bottom of a small aquarium, which can be of approximately 20 liters, together with plants such as Elodeae, Cabomba or Microsorium , as well as a well-fed couple, preferably which have previously been separated for a week. On becoming accustomed to the new environment, the fishes will begin to breed, as described in the part “Breeding Behavior”. Aeration and filtering are optional, although in better aerated water, eggs are healthier and a higher birth rate is achieved. It is probable that better oxygenation of the eggs improves their general conditions. After 20 or 30 days, the substratum with the eggs should be removed, leaving it to dry in a shady spot, so as to slowly lose humidity. The substratum is then placed into a plastic bag, which is identified by a label with information on the name of the species and date of drying. Some aquarists prefer to leave the substratum on an open tray, so as to moisten it daily. This procedure is good, but it is more arduous. Water: The Simpsonichthys are not very demanding fishes concerning conditions of the water, they even support high temperatures and a low concentration of oxygen. They inhabit biotypes with much plant-life which naturally eliminates

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the excess of nitrogen compounds in the water. As pools fill with rain water, this aids in keeping hardness at zero and electric conductibility low. On the other hand, the pH is altered by the composition of the substratum, whereby it is important to know the origin of the species and, consequently, into which bioma it is inserted. In the case of fishes from the Atlantic coastal basin, specifically those inhabiting pools in the Atlantic Rain Forest, the substratum of pools from this region is formed by the decomposition of leaves which thus causes the water to be very acid. In some cases the pH is as low as 4,5, although the most frequent is around 5,5 to 6,0. As to fishes which inhabit the São Francisco river basin, to the north of the town with the same name, here the substratum is composed of very fine clay which keeps the pH of the water neutral or slightly alkaline at 7,2. Regarding fishes residing in the basin of the Araguaia and Tocantins rivers, these dwell in pools wherein the substratum is composed of decomposing leaves and sand, whereby the pH in these biotypes is around 6,6. As to fishes of the sub genus Simpsonichthys (from the S.boitonei group), and which inhabit the source of several water basins, all arising in the Central Brazilian Plateau, the pools thereabouts denote a high concentration of iron and aluminium, this giving rise to orange-colored water with a high concentration of these minerals. The substratum is constituted of fine earth and decomposing vegetation, generally grass, this causing the pH to be slightly acid at around 6,8.

Biotype of S.punctulatus.

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44

Therefore, the ideal is to repeat the above cited parameters and maintain an average temperature of 22ºC. The Substratum: There are various types of substratum available for aquarists. The ideal is very fine ones, as they better enwrap the egg and consequently advantageously maintain its humidity during the incubation period under dry conditions, thus protecting it during this spell. The ideal point to reach in substratum humidity varies for each species. For those that live in drier environments it is convenient to leave the substratum drier in accordance, whereas for those species that dwell in humid surroundings, it is better to leave it moister. Moisture of the substratum and temperature are important factors at the time of incubating eggs. The amount of substratum is also important. The more the better, as it furnishes the means for the fish to completely execute all the steps in spawning, as well as providing better conservation of the egg at the time of drying, by keeping physical and chemical conditions more stable. The substratum can be loosely placed on the bottom of the aquarium (Photo 1), within a pot (Photo 2) or with the aquarium on a slope (Photo 3). Each breeder will choose the method that pleases him most.





Photo 1

Photo 3

Photo 2

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The most common substrata are: TURF: Compressed turf in biscuit form and protected by a mesh is made in Canada and sold in gardening shops as part of seeders. The use is simple. On placing the biscuits in water, this is absorbed whereupon they swell. The mesh is removed and the swollen turf placed in the aquarium. As it is denser than water, it deposits on the bottom. Turf emits much “ink” into the water, leaving it dark and quickly turning it acid. The aquarist needs to change the turf once every 30 days, on matter of not to affect the pH and color of the water. SPHAGNUM: This is a moss, common in the Brazilian Atlantic Rain Forest, which is to be found in gardening shops, already dry for decorating gardens and vases. The problem with Sphagnum is the acidity it provokes, wherefore it is necessary for the aquarist to always be on the alert as to this detail. It is convenient to grind it, as in this way it forms a very fine layer which helps to enwrap the egg, thus improving drying conditions for the latter. POWDERED TREE-FERN: This is also encountered in gardening shops, but should only be used if ground and sieved. It leaves the eggs in an adequate condition as regards humidity during the period of drying. Nevertheless, it substantially alters the pH of water, leaving this more acid, thus it is recommended to partially change the water once a week. COCONUT FIBER: Only recently being used by Brazilian aquarists, it is also acquired in gardening shops. It is recommended to be ground and sieved before use. The effect on water pH is less, but in itself it is more rigid, so that it is necessary to remove the accompanying excess earth. The ideal is a mixture of all of these, thereby elaborating a substratum with several densities, the lighter layers remaining on top and the heavier ones underneath, in such a way as to reproduce natural conditions in the best manner possible. After the drying period, the turf with eggs should be placed in water to propitiate conditions for the hatching and birth of fry. Turf is placed in an aquarium, whereupon water is slowly added until reaching a height of 10cm. Fry will be born within a period ranging from 30 minutes to 48 hours.

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It is easy to check whether eggs are apt for being placed in water, by simply looking and observing the formation of the embryo. Some of these are agitated inside the egg, turning around as if seeking to burst through the chorion. Some aquarists add microworms to aid in hatching. Theoretically, microworms increase the concentration of CO2 which would be of help in bursting the chorion, besides being good nourishment for the fry. New-born fry are approximately 2mm long, and dispose of a small vitellin sac. After 24 hours, they are already seeking food. In nature the abundance of food favors quick growth, so that in less than 30 days they are already beginning to sexualize. In the aquarium, it is difficult to offer all the food options that are available in nature. Nevertheless, the more one varies nourishment, the healthier and quicker will fry grow. When sexualization begins, it is convenient to separate those already sexualized, mainly the males, as the first ones to arrive at this stage are the dominant “alpha males”, and this may hinder both the growth and appearance of sexual characteristics, especially coloring, of the other males. Physical space is also important. The more available space per individual, the faster will be its growth. Sexual disparity In many species, the birth of a large number of individuals of only one of the sex occurs, for example, mainly males in the S.magnificus group, or females in the S.antenori group. There are indications that this fact could be related to the pH of the water, although, until the present moment, there is no proof. A remarkable experiment on this subject was undertaken by Jim Robinson from Canada. He separated the fry of S.flavicaudatus into pairs and so obtained a larger number of couples. A controlled experiment on sexual disparity in Simpsonichthys Jim Robinson’s problem was with S.flavicaudatus. He only managed to obtain one male for each group of twenty-five females. Thus, he was able to maintain the species, but was unable to distribute them to other breeders. Jim Robinson noted that males did not live so long as females, as has already

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been reported in Chapter 9 Ecology, where it was stated that we encountered more females than males in many pools already in the process of drying up. This may be related to the premature death of males, due to energetic expenditure arising from breeding with various females. During a meeting when this topic was discussed, it was stated that a similar problem occurs with Nothobranchius. It was reported that, on separating fry twoby-two in pots, more couples were obtained. Jim Robinson undertook an experiment with five breeding groups, each group consisting of one male and twenty-five females. The outstanding results from this technique could be related to inhibition by hormones or through the visualization of alpha males, which would thus hinder sexual development in the other males. Other experiments related to sexual parity in fishes have already been done. B. E. Kynard noted that sexual definition in Menida menida (Atherinidae) occurred as a result of genetic determination, together with the temperature of the water in which fry were kept during a certain period in their development. Uwe Romer noted that, in experiments with Apistogramma spp. more elevated temperatures normally resulted in a higher percentage of males, whereas higher values of pH gave rise to a greater percentage of females. Both experiments dealt with variation in temperature. Uwe Romer’s experiment also treated of pH. In the following experiment, both these factors were controlled, as well as any other which could interfere in the results, in such a way that the only variable factor was the number of fry per container. Experimental details The experiment itself was undertaken from March 15th to May 1st, 1999. Eggs from the five breeding groups were collected at the same time, incubated at the same temperature and hatched at the same time and in the same water. Fry from each group were placed in 750ml, 1500ml and 20L containers. Half of the fry from each one of the five groups was placed in 20L aquariums, the other half being distributed into smaller aquariums in such a way that, groups of 5 fry were placed in the 750ml aquariums and of 10 fry in those of 1500ml. All fry born in clutches not included in the experiment were all placed in a

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single 20L aquarium, to be used as an external control group.

Group   Group 1     Group 2     Group 3     Group 4     Group 5   Control

Aquariums

Volume

Fry

4 2 1 2 1 1 2 1 1 6 3 1 4 2 1 1

750 ml 1500 ml 20 L 750 ml 1500 ml 20 L 750 ml 1500 ml 20 L 750 ml 1500 ml 20 L 750 ml 1500 ml 20 L 20 L

5 each 10 each 40 5 each 10 each 20 5 each 10 each 20 5 each 10 each 60 5 each 10 each 40 52

On May 2nd, all the fry in 750ml aquariums were transferred to a single 20L aquarium to complete their development. Likewise, fry from the 1500ml aquariums were also transferred to 20L aquariums. So as to maintain exactly the same conditions, all the 20L aquariums were hitched onto a central filtering system, with automatic water change and a constant temperature of 25ºC.

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Results #1 The results were fascinating! With all the care received, not a single fry died.

Experiment #1

Group 1     Group 2     Group 3     Group 4     Group 5     Control

Numbers

Fry

Males

Females

Ratio

a) b) c)

20 20 40

7 5 5

13 15 35

~ 1:2 1:03 1:07

a) b) c)

10 10 20

4 3 1

6 7 19

2:03 ~ 1:2 1:19

a) b) c)

20 20 40

6 5 3

14 15 37

~ 1:2 1:03 ~ 1:12

a) b) c)

30 30 60

12 8 4

18 22 56

2:03 ~ 1:3 ~ 1:14

a) b) c)

20 20 40

8 6 6

12 12 34

2:03 1:02 ~ 1:6

52

4

48

1:12

The average for containers with 5 fry (a): 37 males, 62 females Ratio: 1:2 The average for containers with 10 fry (b): 27 males, 73 females Ratio: 3:8 The average for containers with half of the fry in only one aquarium (c): 19 males, 181 females Ratio: 1:9 External control group 4 males, 48 females Ratio: 1:12 Conclusions: Based on the results shown above, it appears to be completely obvious that high sexual disparity can be significantly improved, by limiting the number of fry kept together in the initial stages of development, at least when dealing with S.flavicaudatus.

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The process is very arduous, and there is the need for a large number of aquariums. Nevertheless, for certain species that consistently present problems as regards sexual disparity, this method may represent the only way for their preservation. Based on this experiment, it appears that the less fry kept per aquarium, the greater will be sexual parity. Even though the results presented here are obvious, to generalize the conclusion that the procedure works for other species could be dangerous. This experiment has only proved that sexual parity can be controlled in one species alone. We can expect similar results for other species of the genus Simpsonichthys, or even for other South American annual genera, but with reservation. However, based on the results, it would not be risky to affirm that the procedure only affects the sex rate, and that it therefore can be considered as a starting point for other species. It is important to remember that the more fishes we breed in captivity, the less will be removed from nature! At the present speed with which “civilization” is destroying nature, it is up to each one of us to try to breed and distribute these fishes, in an attempt to protect these species. A graduate student from the University of Toronto managed to duplicate the experiment, with almost identical results. The only difference occurred in the groups with a larger number of fry, where the proportion reached 43 females for each male. Curt, another annual fish fancier did experiments with other species and obtained the following results, as summarized in the table below:

Species

Result

Simpsonichthys picturatus

1:2

Simpsonichthys similis

Couples

Simpsonichthys notatus

Couples

Austrolebias bellottii

Couples

Aphyosemion australe

Couples

Aphyosemion elberti

Couples

For those species that present the same problem for the aquarist, I believe this will be a good method to solve it.

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Sicknesses The Simpsonichthys are hardy fishes, and when well-fed and kept in aquariums with water in a good condition, they rarely get sick. Sicknesses only appear when the fishes are stressed, whereupon they diminish the production of protective mucus which woks as a barrier between the fish and its environment, thus protecting it against the attack of fungi, bacteria and other parasites present in the water. A fish in an adequate environment is protected from these assaults. Stress can occur after a long period of transporting fish in plastic bags, as a result of the chemical and physical conditions of the water different from the normal standard for the species, or due to overcrowded conditions in the aquarium, where territorial disputes could intensify, thus leaving weaker fish hard-pressed and without adequate food. The most common sicknesses among the Simpsonichthys are: Ichthyo (Ichthyophthyrius multifilis): Ichthyo is a parasite that attacks weak fishes, appearing as small white spots of approximately 1mm of diameter, all over the fish’s body. It is a sickness mainly common in tropical fish. It is very rare among Simpsonichthys, and I have only noted the presence of this sickness in specimens recently collected from the São Fransisco region, where the water is slightly alkaline. With the trip and consequent adaptation to the aquarium in slightly more acid water, some fishes developed the sickness. Treatment: This can be done by using specific parasiticides found on the market, or by bathing the fish using salt water. This consists of submerging the fish for a few seconds in water with a salt-density equal to that of sea-water. When the fish begins to float, it should be taken out and replaced into fresh water. However, care must be taken, as this is a form of shock-treatment and if the fish is very weak, it can die. It is convenient, under the circumstances, to remove the substratum, for the life-cycle of the parasite develops both in the fish and in the aquarium- substratum. Raising the temperature also helps, as this accelerates the

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parasite’s life-cycle, thus forcing it to return more quickly to the substratum. Oodinium sp. The most common sickness among Simpsonichthys, this appears when there is a sudden drop in temperature. Oodinium of Simpsonichthys, and of killifish as a whole, is a different species from that which attacks other tropical fish. The most indicated treatment is that with a copper sulphate base, although care must be taken, as copper sulphate is extremely toxic, therefore an error in dosage can cause the fish to die. Anchor Worm (Lernia sp.) This worm is an external parasite of fish, possessing a hook at the extremity with which it adheres to the fish, and on being withdrawn causes wounds which are almost always fatal. In some pools on the edge of the São Francisco river, we found fishes with this worm as a parasite. Generally the worm does not trouble the fish when eating or reproducing, but only shortens its life. There is no treatment for removing the worm without causing more harm than leaving it on the fish. In some cases, on cutting away the extremity it finally releases the fish, although this does not always work out. Nematode Parasites: In both N.whitei e N.papilliferus and in their natural environment, we encountered a species of Nematode which lodges either in the abdominal cavity or in the ectodermis. These parasites are large, of a whitish or reddish color, and easily seen by the naked eye. When they are lodged in the abdominal cavity, they feed upon the fish’s gut until it dies. When lodged in the ectodermis they do not cause many problems, only a deterioration in appearance. It is probable that the life-cycle of this nematode is related to some bird. We also found this worm in Lept. aureoguttatus on the south coast of the state of São Paulo and in some Kriptolebias.

Worm parasitizing Krip. caudomarginatus, the same commonly found parasitizing Nematolebias e Simpsonichthys constanciae. Photo: Danilo Paiva

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Systematics The aim of systematics is to order biological diversity, describe this diversity, establish rules, present a general reference system on biological diversity and understand those processes responsible for the generation of this diversity (Amorim, 2002). The first classification systems originated in Ancient Greece. Plato and Aristotle are outstanding, among others, in the initiation of studies on the organization of living beings. A great historical significance is the fact that Darwin himself stated that, the possibility of arranging organisms in a hierarchical system is only explicable on presuming there to be a Phylogenetic Relationship amongst them. In other words, and leading from the presumption that all living being descend from a common ancestor, arrangement of these beings should follow the relationship of its degree of kinship, the so-called phylogeny. Many aquarists are really horrified by systematics and panic at the publication of works with new names (taxa) or the alteration of a former one. Actually, these alterations reflect headway in the study of a certain group of living beings. With the advance in new analytical techniques, including genetical analysis, we can arrive at greater precision both in the composition or alteration of scientific names and in their evolutive relationships. The species concept itself has also evolved. In the past, two species were considered distinct when, on reproducing, this resulted in unfertile descendents. Nowadays the species concept refers to the geographic isolation in which two populations are able to be found. If two populations are geographically isolated one from the other, thus making the exchange of genetic material impossible, they are considered distinct species. Phylogenetic systematists use the synapomorphism concept, in other words,

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the exclusive characteristic of a group or species, the result of one or more mutations altering the former or pre-existing form of a determined characteristic of the living being, to distinguish two species. This concept guarantees the differentiation between two distinct species. The following are the main principles of systematics, with a view to establishing a correct nomenclature for living beings and elaborating phylogenetic relationships, that is, of evolutive kinship between their species, genera, families and orders. As in all science, systematics possesses its own rules. The elaboration of scientific names also follows its own rules: 1-The name must be written in Latin. Latin through being an unused language is not subject to regional influences, thus not undergoing alterations, the names being understandable world-wide. Wherefore, if we say Simpsonichthys magnificus in Brazil, in Europe or in Japan, everybody understands to what fish we are referring. 2- Scientific names are composed of two elements, the first initiated with a capital letter defines the genus and the second, beginning with a normal letter, determines the species. 3- The scientific name is always outstanding in the text, this by using italics or negrito, or by being underlined. 4- The Law of Priority. When one and the same species is described two or more times, the name of the first description is always valid. 5- Names can be in reference to: 5.1 A place Eg: S.santanae in reference to the Santana river which is near to where the species was originally found. 5.2 - A characteristic of the fish Eg. S.multiradiatus a reference to the very numerous rays present on the dorsal fin. 5.3 - To pay tribute to a person Eg. S.carlettoi in honror of André Carletto, one of the discoverers of this species. 6. There are also rules for writing the names of the order, sub-order, family and sub-family.

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For the order, we use the ending iformes. Eg. Cyprinodontiformes For the sub-order, we use the ending oidei. Eg. Apllcheiloidei For the family we use the ending idae Eg: Rivulidae For the sub-family we use the ending inae. Eg: Cynolebiatinae When working on the classification of a species, several Morphological and Morphometrical analyses of the fish are undertaken. These analyses require scientific and specialized knowledge in systematics, for it is necessary to diaphanize the fish, a process in which all the fish’s tissues become transparent except for bony tissue which becomes a pink color. With this method it is possible to elaborate a detailed analysis of the fish’s skeleton and so, compare it with those of other species in order to define the differences. The following drawing relates morphometric measurements.

D M

C

I

F

E

A B

L K

H

G

J

A- Standard length B- Length of the head C- Height of the head D- Height of the body E- Height of the tail peduculum F- Pre-dorsal length G- Pre-anal length H- Pre-pelvic length I- Length of the dorsal base J- Length of the anal base K- Length of the pectoral fin L- Length of the tail M- Diameter of the eye.

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Nowadays, more than 100 characteristics, besides those already presented herein, are considered in the description of a species of Rivulidae, this including sizes and types of scales, pattern of Neuromasts, and color pattern and distribution. At present, 51 species of Simpsonichthys and 2 of Nematolebias, distributed among 9 hydrographic basins, are considered valid (Costa, 2006): - Central Basins of South America: Amazonas, Paraná and Paraguay rivers. - Northeastern Basin: São Francisco, Jaguaribe, Mossoró, Cachoeira, Parda and Jequitinhonha rivers. - Small basins on the east coast of South America. The species Simpsonichthys and Nematolebias belong to the order Cyprinodontiformes, family Rivulidae, and sub-family Cynolebiatinae. The family Rivulidae is endemic to the Americas, whereas the sub-family Cynolebiatinae is so to South America, with the exception of the genus Millerichthys Costa, 1995, encountered in Mexico. Chronology: 1959 The name Simpsonichthys was first proposed by Carvalho in 1959, with a description of Simpsonichthys boitoinei. 1981 Parenti published a paper on the phylogenetic revision of the order Ciprinodontiformes. In this, Parenti considered Simpsonichthys, together with Cynopoecilus Regan 1912, Terranatos Taphorn and Thomerson 1978 and Campellolebias Vaz Ferreira and Sierra 1974, as synonyms of Cynolebias Steindachner, and characterized the group by possessing neither scales on the tail fin nor a pre-opercular canal (Costa, 1989). 1989 Costa raised Terranatos, Cynopoecilus, Leptolebias and Campellolebias to the category of genus, keeping Simpsonichthys as a synonym of Cynolebias. 1996 Costa published the work “Phylogenetic and Biogeographic Analysis of the Neotropcal Annual Fish genus Simpsonichthys (Cyprinodontiformes: Rivulidae). J camp. Biol 1 (3/4)”, wherein he considered the genus Simpsonichthys as valid, through the analysis of 56 osteological characters. Costa proposed a phylogenetic relationship among the species known at the time. 1997 Costa and Nielsen described a new genus and species Spectrolebias

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57

semiocellatus, based on fishes collected in the Araguaia river basin, a tributary of the Amazonas river. The genus Spectrolebias was always very close to the genus Simpsonichthys, in all phylogenetic hypotheses. 1998 Costa, in the work, “Phylogeny and Classification of Rivulidae revisited: Origin and evolution of annualism and miniaturization in Rivulid fishes (Cyprinodontiformes: Aplocheiloidei)”, created the sub-tribe Simpsonichthyna, wherein there are 2 genera: Simpsonichthys and a new genus Nematolebias, with N.whitei e N.myersi being fitted into the latter. 2003 Nematolebias was considered a sub-genus of Simpsonichthys, whereupon, with the description of N.papilliferus, only N.whitei e N.papilliferus were fitted into this sub-genus (Costa, 2003). 2006 More recently Costa, reviewed the phylogenetic relations of the genus Simpsonichthys. After analyzing 116 characteristics among 50 specimens, the genus Simpsonichthys was divided into 5 sub-genera, 3 being new (Costa, 2006): 1- Sub-genus: Spectrolebias: S.semiocellatus, S.filamentosus, S.chacoensis, S.costai and S.reticulatus. 2- Sub-genus: Xenurolebias: S.myersi and S.izecksohni

Simpsonichthys

3- Sub-genus: Ophthalmolebias: S.constanciae, S.bokermanni, S.perpendicularis, S.rosaceus and S.suzarti.

Ophthalmolebias

4-Sub-genus: Hypsolebias: Group flavicaudatus, Group magnificus and Group notatus. 5-Sub-genus: Simpsonichthys: S.boitonei, S.parallelus, S.cholopteryx, S.marginatus, S.zonatus and S.santanae.

Spectrolebias Xenurolebias

Hypsolebias

Nematolebias

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58

In this work Costa revalidated the genus Nematolebias, for he discovered that Simpsonichthys is phylogenetically closer to Cynolebias and Austrolebias than to Nematolebias. The most recent hypothesis regarding the phylogenetic relationship between Simpsonichthys and Nematolebias (Costa, 2006):

Nematolebias Cynolebias Austrolebias Xenurolebias

Simpsonichthys

Ophthalmolebias Spectrolebias Simpsonichthys

Hypsolebias

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During the period from 1981 to 1996, and before 1959, several species of the genus Simpsonichthys were classified as Cynolebias, according to the list below (Costa, 1996). Nominal Species Sub-genus Spectrolebias Spectrolebias semiocellatus Costa and Nielsen, 1997. Cynolebias chacoensis Amato, 1986. Cynolebias costai Lazara, 1991. Sub-genus Hypsolebias Cynolebias alternatus Costa and Brasil, 1994. Cynolebias hellneri Berkenkamp, 1994. Cynolebias fulminantis Costa and Brasil, 1993. Cynolebias antenori Tulipano, 1973. Cynolebias magnificus Costa and Brasil, 1991. Cynolebias stellatus Costa and Brasil, 1994. Cynolebias notatus Costa, Lacerda and Brasil, 1990. Cynolebias trilineatus Costa and Brasil, 1994. Cynolebias antenori Tulipano, 1973. Cynolebias heloplites Huber,1981. Cynolebias flavicaudatus Costa and Brasil, 1990. Cynolebias flammeus Costa 1990 Cynolebias multiradiatus Costa and Brasil, 1994. Sub-genus Simpsonichthys Cynolebias santanae Shibata and Garavello, 1992. Cynolebias zonatus Costa and Brasil, 1990. Sub-genus Xenurolebias Cynolebias myersi Carvalho, 1971. Cynolebias izecksohni Cruz, 1983. Sub-genus Ophthalmolebias Cynolebias constanciae Myers, 1942. Cynolebias bokermanni Carvalho and Cruz, 1987. Nematolebias Cynolebias whitei Myers, 1942. Pterolebias elegans Ladiges, 1957. Nematolebias papilliferus Costa, 2002.

Senior Synonym S.semiocellatus S.chacoensis S.costai S.alternatus S.hellneri S.fulminantis S.antenori S.magnificus S.stellatus S.notatus S.trilineatus S.antenori S.heloplites S.flavicaudatus S.flammeus S.multiradiatus S.santanae S.zonatus S.myersi S.myersi S.constanciae S.bokermanni N.whitei N.whitei N.papilliferus

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The morphological differences between Cynolebias and Simpsonichthys are visually perceptible. Simpsonichthys are of a smaller standard size than Cynolebias. The largest Simpsonichthys reach, on an average, 50mm, and the largest that I have encountered was a specimen of S.alternatus 68mm long. Nevertheless, Cynolebias are much bigger, easily reaching more than 100mm. The largest specimen of C.perforatus that I came across in Itacarambí, was 140mm long. ETYMOLOGY: Simpsonichthys In honror of Mr. Charles J. Simpson, from San Francisco, California - U.S.A. Spectrolebias From the Latin Spectro/ghost, referring to the transparent pattern of the fish. Ophthalmolebias From the Greek ophtalmus/eyes plus lebias/a small fish, the common name used for denomination in the order Cyprinodontiformes, referring to the large eyes. Xenurolebias From the Greek xenos/strange oura/tail lebias/small fish, the name commonly used in the order Cyprinodontiformes, referring to the morphology of the tail fin. Hypsolebias From the Greek hypsi/high lebias/small fish, the name commonly used in the order Cyprinodontiformes, in reference to body-height. Nematolebias From the Greek nema/line, as reference to the cylindrical and slim shape of the male.

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Geographic Distribution Of the 51 known species of Simpsonichthys, 49 are found to be distributed in Brazilian territory, and only two are outside, one in Paraguay, S.chacoensi, and the other in Bolivia, S.filamentosus. Species of Simpsonichthys follow a certain pattern in their distribution, this being related to the course of the river, and to pools being placed in a flat region near to its margins. When there is intense flooding, whereupon it is possible, in some cases, for river levels to rise more than 10 meters above the normal level, the opportunity is ripe for Simpsonichthys to disperse by settling in new pools. Thus, species distribution is related to the course of the river.

LEVEL IN BIG INUNDATIONS

POOL

NORMAL LEVEL POOL

This distribution of groups could also be related to the course of rivers in past eras. This fact justifies using these fishes as biographic indicators. In other words, we could, through an analysis of their distribution, avow former geological formations. An example: In the past, the complete course of the São Francisco river was from south to north, arising in Minas Gerais and flowing out into what is today, the estuary of the Jaguaribe river in Ceará State. In a certain epoch, a mountain

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Simpsonichthys and Nematolebias

range arose, thus forcing the São Francisco river to form a curve to the east, thereby flowing out at a point on the present-day border of the states of Sergipe and Alagoas. On comparing the species of annual fishes found throughout the Jaguaribe and São Francisco rivers basins, we will find the same groups of fishes represented by their respective species. In the Jaguaribe basin, we find S.antenori and Cyn. microphthalmus, which are respectively related to S.flavicaudatus, S.igneus, S.ghisolfi and S.flagelatus, and Cyn.albipunctatus, Cyn.perforatus, Cyn. leptocelphus, Cyn.alttus, Cyn.alternatus and Cyn.gilbertoi, thus corroborating geological data to the effect that the São Francisco river follows this course. It is difficult to imagine a Simpsonichthys moving in a river, so as to

Old course of São Francisco river S.antenori

Current course of São Francisco river S.flavicaudatus, S.flagellatus, S.igneus, S.ghisofii, S.macaubensis, S.mediopapillatus, S.jaubensis.

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make use of its course for distribution, as they do not possess the morphological characteristics necessary to face water currents and deep water, besides presenting easy prey due to their small size and lack of speed. Nevertheless, there is strong evidence that this distribution mechanism occurs, as we always encounter temporary pools at the side of rivers. This form of distribution can possibly occur both downstream as well as upstream, a fact which is easily verified in the Paracatu river basin, regarding the distribution of S.trilineatus, S.auratus and S.virgulatus, as well as that of S.parallelus.

POOL

POOL

List of hydrographic basins, with their respective species:

RIVER

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POOL

1. Jaguaribe river basin Ceará State S.antenori 2. São Francisco river Basin States of Minas Gerais, Bahia and Pernambuco S.flavicaudatus, S.igneus, S.ghisolfi, S.fulminantis, S.flagellatus, S.adornatus, S.magnificus, S.carletoi, S.hellneri, S.stellatus, S.nielseni, S.rufus and S.picturatus. 3. Jequitinhonha river Basin Minas Gerais State S.ocellatus and S.perpendicularis. 4. Urucuia river Basin a tributary of the São Francisco, Minas Gerais State S.similis, S.delucai, S.stellatus and S.zonatus. 5. Paracatu river Basin a tributary of the São Francisco River, Minas Gerais State S. trilineatus and S. alternatus. 6. Taboca river Basin a tributary of Rio da Prata, which in turn is a tributary of the Paracatu river, Minas Gerais State S.auratus. 7. Rio Preto Basin a tributary of the Paracatu river, Minas Gerais State S.virgulatus, S.fasciatus and S.gibberatus. 8. Paraná river Basin a tributary of the Tocantins river S.notatus and S.flammeus.

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9. Crixás river Basin a tributary of the Paraná river Goiás State S.radiosus. 10. Ribeirão Canabrava basin a tributary of the Urucuia river S.brunoi and S.notatus. 11. Central coast of the state of Rio de Janeiro N.whitei, N.papilliferus and S.constanciae. 12. Cachoeira river Basin Bahia State S.bokermanni. 13. Rio Doce Basin State of Espírito Santo S.izecksohni. 14. Itaunas river Basin and the south coast of the state of Bahia S.myersi. 15. Pardo river Basin State of Bahia S.rosaceus. 16. São Bartolomeu river Basin The Federal District S.boitonei. 17. Ribeirão Santana The Federal District S.santanae. 18. Araguaia and Tocantins Rivers Basins States of Tocantins and Goiás - S.costae, S.multiradiatus. 19. Xingu river Basin The state of Pará S.reticulatus. 20. Patos river A basin of the Tocantins State of Tocantins S.marginatus. 21. Formoso river A basin of the Paraná river State of Goiás S.parallelus. 22. Ribeirão do Sapo A basin of the Bacia Araguaia river State of Mato Grosso S.cholopteryx.

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Amazon basin Araguaia-Tocantins rivers basin Jaguaribe river basin

Coastline basin São Francisco river basin Paraná river basin

Main Water Basins of South America.

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67

Ecology This is one of the most interesting chapters, as it concerns the ecology of biotypes and other forms from the fauna and flora that have become adapted to temporary pools. The ecology and diversity of the fauna and flora in these seasonal environments are impressive. Temporary pools offer an ecological niche very rich both in nutrients and breeding environment, not only for the annual fish, but also for other groups of animals and plants. Each biome gives rise to pools with unique characteristics, and so we can divide them in accordance to the biome as, Semi-arid, Cerrado, Amazonia, Central Plateau, Coastal Plain, and Pantanal. The pools of the Central Plateau are the most common, and are inhabited exclusively by Simpsonichthys of the sub-genus Simpsonichthys. In the majority, the depth varies from 50cm to 100cm. There is a standard length per region. In the Cerrado and Semi-arid regions, pools are relatively small with a maximum length of 200m and a width of 10m. In the Amazon and Pantanal regions there are pools that are more than 5km long (Aruanã). In some places in the Amazon region pools merge, thus giving rise to an enormous aquatic ecosystem with seasonal and permanent areas, thereby rendering possible the presence of other groups of fishes in the same pool.

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Where there is abundant vegetation, this maintains a mild water temperature of between 20°C and 24°C, with only slight variation. In pools with little vegetation, or even without, there is a surface layer of water of approximately 15cm, where the temperature is higher, around 30°C, whereas below this layer temperatures remain near to 24°C, wherein fishes are protected.

Pool in the process of drying near to the Urucuia river - MG.

When the pool enters the drying process, the temperature rises and reaches near to 40ºC, this rise occurring even in the case of those provided with plantlife. On the occasion of the discovery of the biotype of S. sp Urucuia, the pool was only 10cm deep and the temperature at 38ºC. Even so, all the fishes were in excellent condition. In the more arid regions, several pools are used as a drinking place for cattle, these being excavated so as to retain a larger volume of water, thus eventually destroying the biotype of annual fishes.

Pool in Januária-MG. Excavated for forming a cattle - drinker and with S.flagellatus.

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The color of the water is highly influenced by the sub-stratum and can vary during the season. At the beginning of the rains, the water becomes muddier, the color varying from a brownish or orange tone to a whitish one, depending on the amount of clay in the sub-stratum. In the Amazon and Pantanal regions, the water is clearer, as there is only a small amount of clay. At the time of heavy rainfall, the water becomes muddier. Below, detail of the substratum of a dry pool in Guanambi-BA. Note the number of snail-shells.

Photo: Rogério Suzart

A grave problem for Simpsonichthys is road drainage areas. Roads are preferentially built in flat regions, places where most pools are to be found. On one side this facilitates access to the pools, but in some cases the deepening or draining of water accumulated on the edges of highways destroys them. An interesting case occurred during the drainage of the road that crosses a pool of S.notatus, S.flammeus e Cyn.griseus (a type locality in the county of Nova Roma in the state of Goiás). On the occasion of its discovery in march, 1989, it was necessary to cross the Paraná river by ferryboat. In 1996 a bridge was built and the road was asphalted. During the building of the bridge and asphalting of the road, the pools were deepened so as to better drain the water that accumulated on the road. In the two following years, 1997 and 1998, with the subsequent deterioration of the biotype, it was no longer possible to collect these fishes at this site. Moreover, it was even believed that they had been totally destroyed. Only in 2002, with the natural recuperation of the biotype and the return of plant-life, the

Simpsonichthys and Nematolebias

70 fishes began to again settle in the pools.

Biotype on the margins of the Paraná river - GO on the occasion of the discovery of S.notatus and Cyn.griseus. At this site, S.flammeus is also abundant.

Maybe its rapid adaptation to new environments is a positive factor in the evolutive success of this group of fishes. In the state of Rio de Janeiro, more specifically in the county of Cabo Frio, there is an artificial pool on the top of a hill, excavated to serve as a drinking source for cattle, and where we found N.whitei in abundance. According to local people, the fishes were brought to the pool in 1992 in order to combat the excess of mosquito larvae. Besides N.whitei, some Poecilideos were introduced, probably Phalocerus caudomaculatus, common in the region. Nevertheless, only N.whitei survived, as the pool-cycle is annual, annual Rivulidae thus being the most adaptable species. This fact shows that the re-introduction of species raised in the aquarium could be plausible, but that we should follow detailed criteria, so as not to commit any serious mistakes in the introduction of species into inappropriate sites and cause additional environmental damage. History shows us that this is a very delicate activity and could generate high ecological unbalance.

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Biotype of N.whitei in Cabo Frio-RJ

In the São Francisco river basin, a sympatric relationship is common, with species of Simpsonichthys pertaining to the notatus or magnificus groups, living in the same pool together with Simpsonichthys of the S.flavicaudatus group, as well as with a species of Cynolebias. Each of these occupies a determined ecological niche in the pool. The groups of S.notatus and S.magnificus are more often found on the margins near to vegetation, where as the group of S.flavicaudatus is encountered in greater abundance in the deeper regions together with Cynolebias. Currently, the major problem for annual fish is the green-house effect, which alone could very quickly extinguish all species of these fishes. Alterations in the rainfall regime, caused by this phenomenon, are faster than the speed of adaptation of species to novel environmental conditions, and owing to the direct impact on the climate world-wide, both South American as well as African annual fishes could possibly be exterminated in a short space of time. Moreover, if the rise of sea-levels is confirmed, the habitats of many populations that live by the sea, such as S.constanciae, N.whitei and N.papilliferus, will be covered by the oceans. A good example is an increase in the consequences brought about by Ël Nino and La Nina, both as regards intensity as well as quantity. These effects substantially alter the period and volume of rainfall in the diverse regions, as well as the occurrence of annual fishes, for droughts are more prolonged and intense, and the years of heavy rainfall are more constant.

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There are three other factors which constitute a risk for several species of annual fishes: hydro-electric plants, real-estate expansion and agriculture. 1- Hydro-electric plants are a serious problem for annual fishes, as pools are near river margins. Thus, with the formation of a hydro-electric lake, this invades these margins, whereby many pools are permanently submerged, their annual cycle being effaced. Also flood control by dams makes the distribution of fishes throughout their hydro-graphic basin difficult. In the specific case of the Sobradinho dam on the São Francisco river, in the state of Bahia, the hydro-electric lake flooded an area, not previously studied, of approximately 100km2 on its margins. As the region is one of the richest in Rivulidae species which were encountered before and after construction of the dam, it is very probable that innumerous pools were destroyed without the resident species having been known. 2- Real-estate speculation is the gravest problem on the coast of Rio de Janeiro State, as several pools are being filled up for the building of summer houses. At present, S.constanciae is the fish that most suffers with the diminution of its habitat. Only two known sites are still preserved, one of them in extremely danger. 3- Extensive agriculture poses another problem for annual fishes. Besides the destruction of original plant-life, there is in many cases the building of drainage canals to run off water, thus impeding the formation of pools and destroying their cycles. Two clear examples of this problem occurred with S.marginatus and S.zonatus. With S.marginatus, the locality where they were found was transformed into a corn plantation. Luckily, a pair was handed over to the breeder Álvaro L. F. Cyrino, who managed to breed and distribute them to other breeders. Therefore, all the fishes of the species S.marginatus existing in aquariums originated from just one couple, collected in 1996. In the case of S.zonatus, a canal was dug to the pool, thereby interrupting its periodic formation in the known locality.

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Drainage canal dug in the pool of S.zonatus. Photo: Dalton Nielsen.

In pools that are drying up, it is common to encounter a larger number of females, this being the case with most biotypes of Simpsonichthys. Three suggestions are raised as to the reason for this. 1º - As the males are the most colorful, probably they are preyed upon first, there remaining a larger number of females. The problem with this hypothesis is in relation to the coloring presented by the males of the genus. Theoretically, if the most colorful attract predators, the less colorful would remain for breeding, whereby throughout generations the species would become less colorful. 2º - During fish courtship, the first males become dominant. These males define a food-supply and reproduction territory. With a drop in water level, there is an intersection of these territories which causes dispute. Losers end up with the need to hide and have less access to food, thus becoming more prone to sickness and premature death. 3º- On the case in question, males simply undergo greater energetic fatigue

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Simpsonichthys and Nematolebias

than do females, through continued crossing with several consorts, thus accelerating their metabolism, this leading to death before that of females.

Pool of S.carlettoi in the drying phase in Guanambi-BA. Fishes remain concentrated and are thus easy to collect.

On the case of most biotypes, Simpsonichthys remain alive for approximately 5 months throughout the year. In some cases there are two rainy periods a year. In the São Francisco river basin, when there is no direct influence from El Nino or La Nina, a phenomenon called Indian Summer occurs, which consists of a dry period with high temperatures between rainy seasons. The occurrence of an Indian Summer implies, in the case of many pools, the formation of two seasons in the same year. Rains begin in the month of september/ october and end in January. During these months we encounter an abundance of both Cynolebias and Simpsonichthys of the S.antenori group, besides a few specimens of Simpsonichthys of the S.magnificus group. In january, with dry weather and high temperatures, the pool completely or partially dries up. The rains return in march, when a large number of Simpsonichthys of the S.antenori and S.magnificus groups are to be found. Nevertheless, the number of Cynolebias is much reduced, or in some cases even non-existent. This leads us to believe that Cynolebias, besides feeding on Simpsonichthys of the S.magnificus group, as has already been observed, has a differentiated cycle of embryonic

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development. In the aquarium, it is easy to perceive those species which undergo greater hardship during a stretch of “Indian Summer”. The time for drying of their eggs is much shorter than is the case of species which are affected with less intensity. An example is that which occurs when comparing S.picturatus , which suffers direct influence from the phenomenon, whereby the drying time is shorter, and S.magnificus, which is only affected sporadically. On the coast of the state of Rio de Janeiro, where N.whitei, N.papilliferus and S.constanciae are to be found, there are two, not always well-defined, seasons a year. There are records of the collection of these species during all the months of the year. Nevertheless, greater occurrence is in the months may/june and november/ december. Below there is a table of the rain periods, according to river basin.

River Basin

Rainy Season

São Francisco

december to april

Tocantins - Araguaia

january to may

Central Plateau

january to may

Jaguaribe

march to june

Jequitinhonha

march to june

South coast Bahia

july to october

Coast of Rio de Janeiro

may/june and november/december

Coast of the state of Espirito Santo

july to october

Xingu

february

Paraguay Pantanal

december to may

Simpsonichthys and Nematolebias

76 Extreme North Rainfall period between june and october

Atlantic Coast Rainfall period between april and august

South region Rainfall period between july and november

Central region Rainfall period between november and march

Brazilian map of rainfall distribution.

Dry pool of S.fulminantis in Guanambi-BA.

Simpsonichthys and Nematolebias

Snail often found in pools where Simpsonichthys species occur. This is the intermediate host of the Platyhelminth Schistosoma mansoni, which transmits schistosomiasis.

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78

WATER Pools inhabited by Simpsonichthys, maintain a pattern in accordance with the biome where they are located. These can be split into 6 biomes: 1. Semi-arid 2. Cerrado 3. Amazonian 4. Central Plateau 5. Pantanal 6. Atlantic Coastal Plains

Map showing the distribution of the main Brazilian biomes.

The soil of each biome defines the chemical conditions of the water. Soil

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composition can vary from clayey, sandy or a compound of decaying organic plant-matter. In general, electric conductibility is very low, less than 15µS/cm, due to the low presence of ions dissolved in the soil of these regions. In more clayey soils, common in the region of the Caatinga and in some places of the Cerrado, a slightly alkaline pH, of around 7,0 to 7,4, is to be found.

Biotype of S.carlettoi with a predominance of clayey soil.

In soils consisting of decomposing organic plant-matter, the pH varies from slightly acid to extremely acid, these conditions being the most common in pools of the Amazonian, Pantanal and Atlantic Rain Forest regions. In the Pantanal and Amazonian regions, the pH encountered in pools varies from 6,4 to 6,8, whereas in the Atlantic Rain Forest this can drop to 4,6. Some of these substrata allow fish to dive for spawning at great depths of up to 40cm from the surface, whereas others do not possess the same permeability, thus permitting only shallower dives.

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Photo of the substratum to be found in the Atlantic Rain Forest consisting of decomposing leaves. Photo: D. Nielsen.

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PLANT-LIFE In most of the pools, plant-life is abundant. In some places it is even extremely difficult to collect fishes, due to the large amount of aquatic plants, which make it toilsome to drag a net through the water. Plants play an important role, as, besides keeping water temperature low, they eliminate all excess nitrogen compounds from the pool. In many pools there is such an abundance of plant-life that the water of the pool disappears. The most commonly found plants are: - Echinodorus sp. - Ultricularias sp. - Nynpheas sp. - Marcileia sp.

A pool in Bom Jesus da Lapa with Equinodorus subalatus in flower.

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Enormous leaves of Nynphea sp and Echinodorus sp found in a pool containing Simpsonichthys Photo: Dalton Nielsen

Marcileia sp.

Photo: Dalton Nielsen

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FAUNA Aquatic insects, chelonians, amphibians, mollusks, crustaceans and annelids, besides other groups of fishes, are often to be found in temporary pools. Not only the annual fishes make use of these temporary biotypes, but also a large range of the fauna. Some use the pools to breed, or to pass one phase of their lives, while others, such as the annual fishes, are totally dependent on these pools for their entire life-cycle. Throughout the São Francisco river basin, a crustacean, the popular “Branchonetas” with the scientific name Dendrocephalus brasiliensis, is to be found in several of the annual pools. This crustacean is very much like the saltwater artemia and probably constitutes part of the diet of Simpsonichthys. They are filterers and feed on plankton.

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There is a large variety of aquatic insects, the most common being the coleopterons (Beetles), besides the larvae of dragonflies. Chelonians are sporadically encountered in pools.

Chelonian of the genus Phynops found in a pool near to the town of Bom Jesus da Lapa-Bahia.

Fishes of other groups often to be found in pools, together with Simpsonichthys:

Cichlid from the São Francisco river basin. Dianema sp.

Hoplias sp e Gymnotus sp encountered in a pool together with S.delucai

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Characids met with in a flooded annual pool. Photo: André Carletto

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Simpsonichthys and Nematolebias

PREDATORS

The Simpsonichthys are not subject to many predators, these being certain aquatic coleopterons and a few birds, since they are small-sized fishes and therefore difficult to catch, besides representing little energetic gain for both birds and other groups of fishes. The pacific behavior of Simpsonichthys, in relation to other groups of fishes, is commonly perceived in the aquarium. They do not possess the voracity of the Characids and Cichlids in relation to food and are easy prey for larger-sized fishes. The only predator sharing the same conditions are Cynolebias. A Cynolebias has already been observed attacking and feeding on a Simpsonichthys of the group S.magnificus.

Photo: Marcos Almeida. An aquatic insect.

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Subgenus

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Subgenus: Simpsonichthys The Simpsonichthys group inhabits the central Brazilian plateau, which is a region with an average altitude of 1.000m (Costa, 1995). In the central Brazilian plateau and in areas where the Cerrado biome predominates, there are to be found the sources of various important Brazilian river basins, namely those of the Tocantins, Araguaia and Paraná rivers, besides various important tributaries of the São Francisco river. Only seven species of this group are known, although there are probably others distributed throughout the region, but as their habitat is not common to the genus, their localization becomes more difficult, even more so, due to the advance of farming and animal husbandry in the area, which could account for the destruction of several sites with species as yet unknown. The known species are: 1- S.boitonei 2- S.zonatus 3- S.santanae 4- S.parallelus 5- S.cholopteryx 6- S.punctulatus 7- S.nigromaculatus An outstanding characteristic of this group is the absence of pelvic fins in four of the species: S.boitonei, S.nigromaculatus S.parallelus and S.cholopteryx. Cladogramme of the phylogenetic relationships of species from the subgenus Simpsonichthys (Costa, 2006): S.cholopteryx S.parallelus

S.boitonei

S.santanae S.zonatus

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S.boitonei, Carvalho 1959.

Photo: M. Chauche.

CLASSIFICATION: A new genus and new species of annual fish from Brasília, with a note on annual fishes from the Baixada Fluminense, Rio de Janeiro, Brazil (Pisces, Cyprinonodontidae, Fundulinae) Bulletin from the National Museum, Rio de Janeiro, Brazil, 201:1-10, figure. ETYMOLOGY: In honor of the Director of the Brasília Zoo, José Boitone. TYPE LOCALITY: County of Brasília, in the Federal District. SIZE: Males 45mm, females 35mm. BACKGROUND: In 1958, when catching fishes for feeding the birds of the zoo in Brasília, the city which was then being built to become the new Brazilian capital, a certain fish called the attention of a zoo employee, due to its beautiful reddish coloring.

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He took it to the Head of the Zoo, at that time Mr. José Boitone, who in turn sent it to the ichthyologist Antenor Leitão de Carvalho, who published a description in the following year. A certain characteristic which intrigued Mr. Antenor was the absence of pelvic fins. For this reason, he allocated the species to a new genus Simpsonichthys, this being the first fish to be identified therein. It became popularly known as Pirá-brasília (pirá = fish), thus, ‘the fish from Brasília’. In 1995, the fish lost to the Mained Wolf in an election for the animal-symbol of the city of Brasília. This was due to the error of attributing to the species the characteristic of being hermaphroditic. CAPTIVE BREEDING: A somewhat difficult fish to breed, it is recommended to the aquarist with a certain experience, as there is variation in the rate of development of embryos in eggs of the same clutch. In the 80’s, it became common in European aquariums through the exportation of a certain number of batches to Germany. In 2005, in the scientific paper Oscar A. Shibata: Reprodução do pirábrasília, Simpsonichthys boitonei Carvalho (Cyprinodontiformes, Rivulidae), e caracterização de seu habitat na Reserva Ecológica do Instituto Brasileiro de Geografia e Estatística, Brasília, Distrito Federal, Brasil, in a very precise analysis on both habitat and breeding, the author states: “Drying of the pool’s substratum does not seem to constitute an essential factor in embryo development of certain eggs, for even without this drying, the existence of distinct generations in the habitat was observed. This had already been previously noted by Wourms in 1972”. On supposing that the determinant factor for the embryo to enter or not into the Diapause, is the concentration of oxygen, we can presume that when the swamp dries up, and due to its subsequent compacting, there is a reduction in the supply of oxygen to the egg. With the return of rain, the soil loosens up and there is an increase in aquatic flora, all of which aid in increasing the supply of oxygen to the egg.

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HABITAT AND DISTRIBUTION: Five localities are known, all situated around the city of Brasília. Four are on the margins of the Riacho Fundo, and there is one population on the bank of the Ribeirão Gama (Shibata and Garavello, 1992). It used to be found in wet fields in the flood-plain of the São Bartolomeu river, a basin of the Paraná river in the Federal District. Unfortunately, according to a study undertaken by the United Nations Education, Science and Culture Organization (UNESCO), divulged in 2002, 80% of the marshland where a large part of the rivers of the Brazilian cerrado region arise in the Federal District, have since disappeared. Two populations, with around a hundred fishes including males and females, were encountered on the Ecological Reserve of the Instituto Brasileiro de Geographia e Estatística (IBGE), bordering the DF-001 highway. The area consists of 1.350 hectars, 58% of which is composed of swamps. Through a Federal Resolution in 1986, the reserve was included in the Area of Relevant Ecological Interest Capetinga-Taquara. The “Ludwing Swamps” (Eiten, 1978) predominate in the Federal District. These are transition areas located between flood-plains and gallery forest, of variable extent, where vegetation from both environments occur. S.boitonei are generally to be found in grassy fields, little different from the above cited. We often encountered Rivulus pictus and Astyanax sp in the same habitat as S.boitonei, a fact which had also been commented on by Antenor de Carvalho in 1964, and was also noted by Shibatta in 1992. The presence of these species together is justified by the linking of temporary swamps to nearby streams. The three species living together is possible due to the difference in spatial occupation of the water column. While we encounter S.boitonei close to the substratum, Astyanax sp. is to be found at mid-depth whereas Rivulus pictus stays nearer to the surface (Shibatta & Bennemann, 2003). The environmental conditions encountered by Shibatta in a pool with S.boitonei, in the Ecological Reserve of the Instituto Brasileiro de Geografia e Estatística (IBGE), are so described. “According to the IBDF (1979), the Brasília region is placed on PreCambrian rocks, vested with acid intrusion, thus justifying the low pH found in most of the aquatic environments of the region”. “The low electric conductibility indicates that pools are formed by rain-water

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and underground reserves in a soil poor in ions” (CODEPLAN/GDF 1984). “The concentration of oxygen indicates values lower than those of other aquatic environments of the region, the variation between daytime and night probably occurring through interruption in the plant photosynthesis process, as was also observed by Nico & Taphorn (1984)”. According to SCHÄFER (1985), “the low concentrations of dissolved oxygen and low pH make it difficult for bacteria to proliferate”. Probably this fact contributes to the slow decomposition of plant matter, which is typical of turfs, thus providing greater protection for eggs buried in the substratum. As cited in the chapter on ecology, Shibatta noted the greater presence of females than males in marshes, and suggested that this fact is related to territorial behavior in males. In species with aggressive and polygamous males, these conditions are often encountered (Magurran & Garcia, 2000). With this we can suppose that the eggs of S.boitonei hatch without the need for their substratum to completely dry, whereby 2 or more generations may occur in the same rainy season.

S.boitonei

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S.cholopteryx, Costa, Moreira and Lima 2003.

Draw: Stefano Valdesalici

CLASSIFICATION: Simpsonichthys Cholopteryxn.sp. (Cyprinodontiformes: Rivulidae: Cynolebiatinae): a new dwarf annual fish from the upper Araguaia river basin, central Brazil. ETYMOLOGY: From the Greek cholos (multilated, crippled) and pteryx (wing or fin), insinuating the lack of pelvic fins, a characteristic shared by S.boitonei and S.parallellus, whereby the name is dealt with as a combined-noun. TYPE LOCALITY: It was discovered in seasonal pools on the margins of “Ribeirão do Sapo”, in Mato Grosso State, the Araguaia river basin. SIZE: Males 23,5mm, females 19,5mm. BACKGROUND: Discovered by Flavio T.C. Lima, an ichthyologist from USP (University of São Paulo) in May, 2001, it was never existent among aquarists. During the following year, a new scientific excursion located two new sites in the neighborhood with S.cholopteryx. Classification work was published in 2003. The species S.cholopteryx, together with S.parallelus and S.boitonei, belong to the subgenus Simpsonichthys, all identified by not possessing pelvic fins.

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CAPTIVE BREEDING: To date there is no register of this species in captivity. Nevertheless, due to geographic and phylogenetic proximity, the same patterns as those applied to S.parallelus are possibly relevant. HABITAT AND DISTRIBUTION: Found in the Araguaia river basin in its upper reaches, in flooded areas near to the stream “Ribeirão do Sapo”. The pools consist of a very shallow hollow, with a maximum depth of 40cm, containing dark-colored water and with the presence of aquatic plants. Other species of fish are encountered in the same spot, such as Riv. litteratus, Hyphessobrycon sp. and Rhamdia sp

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S.nigromaculatus, Costa 2007.

CLASSIFICATION: Simpsonichthys nigromaculatus, a new miniature seasonal killifish from the upper Paraná river basin, central Brazil. (Teleostei: Cyprinodontiformes: Rivulidae). Ichthyol. Explor. Freshwaters, Vol. 18, No. 3, pp. 199-203, 2 figs., 1 tab., september 2007. ETYMOLOGY: In reference to the black spots on the dorsal fin of males. TYPE LOCALITY: A flood-plain on the margins of the Prata river, a tributary of the Aporé river, on the upper Paraná river basin, in the state of Goiás. SIZE: Males 25mm. BACKGROUND: This is another of recently described species that does not possess pelvic fins. Even though its description was only published when the book was already in the final stages, there was still time for a quick trip to the site in the beginning of 2008, where the species was encountered on the typical locality itself. A very outstanding fact that occurred during the collection was coming

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across certain adult males without the black spots on the dorsal fin. They were in the minority, but even so, they represented around 8% of all the males in the population. CAPTIVE BREEDING: Through being phylogenetically very close to S.parallelus, they probably follow the same breeding pattern. HABITAT AND DISTRIBUTION: This consists of pools close to the Prata river, in the state of Goiás, and following the same characteristics as pools of S.parallelus and S.cholopteryx. Specimens of Riv.scalaris were also found in the same pool, but where the Rivulus was present, S.nigromaculatus was absent. The water of the pool was located among grass, the presence of several deep holes, more than 70cm deep amid the grass being common, thus making fish collection very difficult. The substratum was composed of organic matter originating from decomposing leaves, while water pH was low, only 4,5, and electric conductibility close to zero. DISCUSSION: In 2006, I sent an aquarist friend, Gustavo Grandjean, a couple of S.parallelus collected on the margins of the Formoso river. Among the fishes from the first generation, a male was born with characteristics described for S.nigromaculatus (Photo below).

Photo of S.parallelus This specimen, from the Formoso river population, displays a black spot on the dorsal fin. Photo: Gustavo Grandjean.

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As already reported, in the collection undertaken at the S.nigromaculatus type locality in february, 2008, some males were found without the black spot on the dorsal fin (Photo below).

Photo S.nigromaculatus without the black spot on the dorsal fin

The doubt is clearly, how are the species to be correctly identified, if in populations of S.parallelus we also encounter fishes with the characteristics of the species S.nigromaculatus, whereas in the population of S.nigromaculatus we only find fishes without the characteristic black spot? Maybe in this case it is necessary to perform a genetical analysis, apart from the morphological one already done.

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S.parallelus, Costa 2000.

Photo 1: female of S.parallelus Dalton Nielsen Photo 2: male of S.parallelus Gustavo Grandjean

CLASSIFICATION: Description of four new annual species of the genus Simpsonichthys (Cyprinodontiformes: Rivulidae) from the basins of the São Francisco and Paraná rivers, northeastern and central Brazil. Aquarium 25: 8-15. ETYMOLOGY: From the Latin parallelus (parallel) in reference to the pattern of stripes in the male. TYPE LOCALITY: The Emas National Park, in the state of Goiás. SIZE: Male 22,6mm, female 20,3mm. BACKGROUND: In the year 2000, Wilson Costa published the description of a new species of Simpsonichthys from the S.boitonei group. Many species of Simpsonichthys had already been discovered over the last few years, but few were related to this group. The discovery of this species and later, of S.cholopteryx, opened up an enormous possibility of the existence of innumerous species of Simpsonichthys all over the central Brazilian plateau, especially in the state of Goiás, for the

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geographic localization of S.parallellus and S.cholopteryx is approximately 500km from that of S.boitonei, and there is no knowledge of the presence, in this gap, of any species of Simpsonichthys, nor that of any other species of annual fish, except for the recent discovery of Pituna brevirostrata, near to the town of Goiania. One great problem is the predominant economical activity in this region agriculture which has probably accounted for the extermination of several species that we have not even come to know. The great restriction for us to be able to introduce this species to aquarists, refers to the place where it was discovered, as it was encountered within a National Park for Environmental Preservation, the Emas National Park, to the southeast of the state of Goiás, near to the frontier with the state of Mato Grosso. On analyzing a satellite photo of the region, I noticed that a large part of the course of the Formoso river is outside the park. So probably there could be other pools with this species thereabouts. Later, I received the news that a population had been discovered around 40km down-river. With the satellite photos on hand, plus additional information on the finding of a new population, I scheduled a trip with the aim of encountering both S.parallelus and S.cholopteryx. As I possessed the coordinates in GPS of the site of the latter, I thought this would be easier to find, but in fact it proved to be otherwise. I invited some friends to accompany me on this adventure. It was to be a long trip, with little time to look for the fishes, but nobody managed to find the opportunity to accompany me, so in the end I took the trip alone. I left Taubaté very early on the april 27th, 2006, heading for Chapadão do Céu, a small town on the edge of the Emas National Park, in Goiás State. After driving 1.l4lkm, I arrived there near to 8p.m.. The first step was to arrange a place to sleep and take a long bath. On the following day, I woke up early and left, with the idea of trying to find an access to the Formoso river. As the normal roads did not reach close by, the only alternative was to enter a farm and try to arrive there by passing through, as pools with Simpsonichthys are normally in the neighborhood. In the first farm I entered, I found a flood-plain with good characteristics for annual fishes, but full of Rivulus aff. scalaris. There were so many of these that it was possible to catch them by hand. After three frustrated attempts to reach a point close to the Formoso river, I came upon an earth-road leading towards the seat of a farm. On arriving there,

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I received indications on a trail to the river. The trail was around five kilometers long and passed through pasture and wooded areas. Attaining the vicinity of the Formoso river, I observed a flood-plain in which there was a pool with various tufts of grass, in appearance very much like the S.zonatus biotype. On casting the net in a more open area, several specimens of S.parallellus were caught, all already sexually differentiated adults. Sympatric with these there was the same species of Rivulus, the Rivulus aff. scalaris, though in smaller number. In 2007, I returned to the region where I encountered two more populations of S.parallelus, one on the banks of the Formoso river itself, only more up-river, and the other on the margin of the Jacuba river. Incidentally, these two rivers meet to form the Corrente river. DESCRIPTION: It is the smallest species of Simpsonichthys discovered so far; the largest specimen collected was only 3,2cm long. One outstanding characteristic of the species is the absence of pelvic fins, the same as occurs with S.boitonei. The males possess a unique color pattern, with vertical blue stripes all over the body, their single fins being orange with a black edge and their caudal fin elliptic. It possesses blue eyes with a dark vertical stripe, also unique in the genus. The coloring of the females is a light yellowish brown, with a black patch in the central part of the body and darker vertical stripes. On the fins there are small and irregular dark spots. CAPTIVE BREEDING: (by Francisco Falcon) Notwithstanding its very small size, as soon as the fishes were placed into the aquarium, there was dispute for territory. The dominant males killed the smaller ones, and sometimes even attacked the females. After these first moments, which lasted two days, the fishes began to spawn and this with reasonable frequency. I separated two aquariums for this species, the first with one couple (a small aquarium measuring 25cm), and the other larger (60cm) with three males and two females, the latter also containing a small round aquarium serving as a vessel for the substratum (coconut husk in powder form), where the fishes spawned. Curiously, I encountered more eggs in the aquarium with only one couple than in the other,

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maybe because there were more males which passed the time harassing one another instead of courting females. After one month of spawning, I removed the substratum and examined it looking for eggs. The eggs are disproportional to the size of the fish, being big and easy to see in the substratum, as also occurs with S.zonatus and S.boitonei. Incubation follows that of the other species of the genus, in such a way that after 60 days in a hot environment most of the eggs are ready to hatch. From a turf collected on july 1st and kept at environment temperature (26ºC), on August 25th there were around 20 eggs still clear, about 5 with embryos but not yet ready to hatch, and several eggs ready to hatch. I removed the eggs not yet ready by hand from the turf, passing them to a smaller bag to be hydrated later, and then moistened the substratum with the eggs that were ready. In about one hour the first fry appeared, around 15, proportionally large and hungry. As initial nourishment, they were given microworms and artemia naupilii. They grew quickly, being completely sexed in four weeks in the first batch I raised, with slightly more females than males (around 7 males and 10 females). HABITAT AND DISTRIBUTION: 2 The pool is round-shaped, with an area of approximately 400m . The depth was 50cm and the water clear with a pH of 6.8 and a carbonated and total hardness equal to 0. With the discoveries of 2007, it is possible that there are more populations of this species distributed throughout the rivers Formoso, Jacuba and Corrente. The Jacuba river population is the most beautiful, as it possesses a larger blue stripe around the edges of the dorsal and anal fins.

S.parallelus, Jacuba population. Photo: Gustavo Grandjean.

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S.punctulatus, Costa and Brasil 2007.

CLASSIFICATION: Simpsonichthys punctulatus n. sp. a new seasonal killifish (Teleostei: Cyprinodontiformes: Rivulidae) from the upper São Francisco River basin, central Brazil. Vetebrate Zoology 57 (1) 2007. Museum für Tierkunde Dresden, ISSN 1864-5755, 09.08.2007. ETYMOLOGY: From the Latin punctulatus with spots, a reference to the blue spots on the males flanks. TYPE LOCALITY: Formosa county in the state of Goiás. SIZE: Males 32mm, females 25mm. BACKGROUND: This species was discovered in the 70’s by Rosário La Corte and Roberto Takase. It was initially identified as S.boitonei with pelvic fins.

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In the beginning, the collectors did not establish the fact that the specimens from this population possessed pelvic fins. In a lecture where Sr. Rosário La Corte presented a photo of the species as being S.boitonei, a member of the audience pointed out this discrepancy. Over the last thirty years, the species had no longer been encountered. It was even believed that the S.boitonei with pelivic fins had become extinct. In march, 2007, while looking for new species of Rivulidae, by chance Didier Pillet and I discovered a pool with the species, near to the town of Formosa. The site is easy to reach and we had already passed by it several times, but that year I noted that the whole area was flooded, maybe so due to the recent heavy rainfall. CAPTIVE BREEDING: Apparently breeding conditions are the same as those for S.santanae and S.boitonei. After distributing several couples among aquarist friends, I prepared three aquariums, the first with one male and three females, the second with one male and two females and the third with a couple. The fishes adapted quickly, but did not manifested breeding behavior. At around this time, I took another trip to try to find S.cholopteryx. On the occasion, I observed that water of the pools that sustaining the subgenus Simpsonichthys contained a large amount of iron, the color of the water including has an orange hue. I placed a few rusty nails into the aquarium, and on the following day, I observed the males executing breeding display. Courtship display is a little different in the subgenus Simpsonichthys. Instead of expanding the single fins, there is a folding of these, followed by a quivering of the body as a whole. An outstanding characteristic in this species is the prolonging of the rays in the male dorsal fin, these becoming long in old males. HABITAT AND DISTRIBUTION: Only the type locality is known, and according to information furnished by Sr. Rosario La Corte, it is the same as that encountered in the 70’s. The pool is around 800 meters long and 100 meters wide, with an average

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depth of 80cm. Plant-life was composed of grass, the pool itself being located at the side of the Bezerra stream, in the Paracatu river basin. The water was of an orange color with an abundance of Quironomos sp. therein. The substratum of the pool was composed of an orange-colored clay, with S.punctulatus as the sole inhabitant. Due to the large amount of water in the pool, there was a heavy flow of water from this to the “Córrego Bezerra”, an indication that annual fishes use the rivers as a means of distribution. Pool pH was 5,45, electric conductibility 18µs and water temperature 22,5ºC.

Photo: Rosário La Corte taken in 1983.

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S.santanae, Shibata and Garavello 1993.

Photo: Didier Pillet.

CLASSIFICATION: Description of a new species of the genus Cynolebias Steindachner from central Brazil (Pisces: Cyprinodontiformes). Communication from the “Museu da Pontífica Universidade Católica do Rio Grande do Sul” 5 (11):179-195,figures, map. ETYMOLOGY: Referring to the nearness with the “Ribeirão Santana” (a stream named Santana). TYPE LOCALITY: The right margin of the “Ribeirão Santana”, in the Federal District. SIZE: Males 32mm, females 25mm. BACKGROUND: Discovered in 1985 by João Paulo Viana, the species was only described by Oscar Shibata and Julio Garavello in 1992. For a long time attempts to capture it were unsuccessful. It was only in

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2006, when on a trip with Fabrício de Oliveira Pereira, were we able to once again encounter the species in the same typical locality. Many questions have been raised as to whether S.santanae was synonymous with S.boitonei, but recent phylogenetic studies have shown that S.santanae is more closely related to S.zonatus than to S.boitonei. CAPTIVE BREEDING: It has proved to be an easy species to breed in captivity, with an average egg-drying time of around 70 days at an average temperature of 22ºC. Fry were big at birth and accepted artemia naupilii at once. Apparently it will be easy to keep as a hobby fish, as it is very beautiful and easy to breed. HABITAT AND DISTRIBUTION: Only the typical locality is known, in a flooded area on the banks of the Ribeirão Santana, in the Federal District. The pool is extensive, with a maximum depth of 80cm and containing orange-colored water. Throughout its length, plantlife consists of grass. Only this species was found at the site, besides a few small characins. Water temperature was 20, 20ºC, whereas the air temperature was 24, 80ºC. Altitude was 860m and the pH of the water 6,20. The site presents a broken relief, which can, theoretically, restrict distribution.

S.santanae biotype

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S.zonatus, Costa and Brasil 1990.

Photo 1: Male - Photo 2: Female

CLASSIFICATION: Description of two new fishes of the genus Cynolebias (Cyprinodontiformes: Rivulidae) from the São Francisco river basin, Brazil. Ichthyol. Explor. freshwaters 1: 15-22. ETYMOLOGY: With zones or stripes, in reference to the color-pattern of the males. TYPE LOCALITY: The county of Guarapuava, in the state of Minas Gerais. SIZE: Males 30mm and females 25mm. BACKGROUND: This species was discovered in 1989, in a pool in the Urucuia river basin, and described in 1990. In 1991, I was at the typical locality where we found S.zonatus. Already at that time there was pressure on the part of farmers to transform the area into farm land. Until 1996, we received reports on collections where the species was still to be found. I returned to the spot in 1999, 2002, 2005 and 2006, and on none of these

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occasions could we find the species again. In 2006, a canal was dug to drain the water to avoid forming pools, so as not to prejudice soya-bean plantation. CAPTIVE BREEDING: This is a very beautifully colored fish and easy to breed in captivity, which recommends it to beginners. However, care must be taken with water conditions, by maintaining a neutral pH and zero hardness. On following these recommendations and keeping the eggs in moist turf for 60 to 80 days, at a temperature between 20ºC and 25ºC, newborn fry will be of a good size and take to feeding on artemia naupilii from the first. HABITAT AND DISTRIBUTION: The original typical locality is known. Besides this, another population has been discovered close to the town of Arinos, where only one collection has been undertaken so far, giving rise to specimens without the black dots on the dorsal fin. The original typical locality has already been destroyed to give place to soya-bean plantation. Nevertheless, there are signs of the existence of other populations.

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Hypsolebias, Costa 2006. Only recently created, the subgenus Hypsolebias is composed of 31 species, distributed among the basins of the mid-São Francisco, mid-Jequitinhonha, upper and mid-Tocantins and Jaguaribe rivers. The subgenus is distinguished from the others by possessing a second longer than wide pharyngobranchial arch, the presence of a lateral-ventral and a shortened hiomandible, although this also occurs in certain species of Spectrolebias. It is the most numerous and diversified subgenus of Simpsonichthys. Phylogenetic relationships among the groups of Hypsolebias (Costa, 2006):

Grupo da S.antenori Grupo da S.flammeus Hypsolebias Grupo da S.notatus Grupo da S.magnificus

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Group S.antenori This group is composed of 8 species distributed in the Jaguaribe and midSão Francisco. They are easily identified by the pattern of colored stripes present in the males, as well as filaments on the dorsal and anal fins. There are four large areas where they are endemic, and are generally to be found together with Cynolebias or other Hypsolebias of the groups S.magnificus or S.notatus. Cladogram with the phylogenetic relationships of the group S.antenori (Costa, 2006).

S.antenori S.ghisolfii S.igneus

S.flavicaudatus S.flagellatus

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S.antenori, Tulipano 1973.

Photo: Dr. Roger Brousseau.

CLASSIFICATION: Cynolebias antenori. J.American Killifish Assoc. 6:23-25. ETYMOLOGY: In honror of the discoverer Antenor de Carvalho. TYPE LOCALITY: County Russas, in the state of Ceará. SIZE: Males 55mm, females 45mm. BACKGROUND: This species was first discovered in 1945 by Antenor de Carvalho in a place called Russas, in the state of Ceará and in the Jaguaribe river basin.

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In 1952, Myers cited this species for the first time as Cynolebias antenori, in a magazine for aquarium fans, thus paying homage to its discoverer, although this citation was not accompanied by a description, thereby rendering it a nomem nudum. In 1972, the species was found once again and subsequently distributed to a few American aquarists. In the following year, John Tulipano published an article on captive-breeding of the species, whereby he minutely described its coloring, referring to the species as Cynolebias antenori. Since Tulipano used this denomination for the fish, besides presenting characters and a diagnosis on its color pattern, this became a valid scientific name, with Tulipano as the author of its description. In 1981, J. Huber described Cynolebias heloplites, based on specimens born in aquariums and fishes collected by Huber herself. Later on it was shown that one is dealing with one and the same species, and so C.heloplites became a synonym of S.antenori (Costa, 2002). CAPTIVE BREEDING: This follows the same pattern as that of the other annual fishes of the group. This is a very prolific fish, producing an extremely delicate egg, thus making it very important to periodically check the eggs as well as the humidity level of the turf, in order to maintain the integrity of the former. Males begin courtshipdisplay of females by altering the body-color, thereby becoming a more intense blue. Subsequently, both plunge into the substratum, where spawning occurs. On emerging, males begin to search for other females so as to repeat the process. There has been a pronounced improvement in success at maintaining eggs, by adding a small amount of calcium to the water, thus probably aiding in the constitution of the egg chorion. In its natural habitat, the substratum of the pool is composed of clay containing this chemical element. HABITAT AND DISTRIBUTION: Seasonal pools situated in the Jaguaribe river flood-plain and in coastal basins between the states of Ceará and Rio Grande do Norte (Costa, 2002). It is able to be found together with Cyn.microphthalmus in pools with a clayey substratum.

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S.flagellatus, Costa 2003.

CLASSIFICATION: The Simpsonichthys flavicaudatus species group (Cyprinodontiformes: Rivulidae: Cynolebiatinae): phylogenetic relationship, taxonomic revision and biogeography. Ichthyol. Explor. freshwaters vol 14, nº1, pp.31-60, 17 figs. march 2003. ETYMOLOGY: From the Latin flagellatus, whipped, in reference to the long filaments on the male’s fins. TYPE LOCALITY: The county of Bom Jesus da Lapa, in the state of Bahia. SIZE: Males 72mm, females 65mm. BACKGROUND: Discovered in the beginning of the 90’s, until 2003 it was considered as S.flavicaudatus. In 2003 there was a separation of the species. Up till then, many captive S.flagellatus in aquariums were going under the name of S.flavicaudatus.

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Therefore, it is important that we should always know the originating population of our fishes, for when there is a systematic revision, it could happen that a determined species be considered a new one. CAPTIVE BREEDING: Even though this fish is abundant in nature, in captivity it has proved to be difficult to breed in aquariums. The problem consists of keeping eggs during the drying stage and until hatching. The birth rate is very low, and the loss of eggs during drying of the substratum high, even though spawning gives rise to a large number of eggs. It could be that this species needs a different degree of substratum humidity, something which we do not as know yet. HABITAT AND DISTRIBUTION: Distribution is spread over an area of approximately 330km2, in seasonal pools in the flood-plain of the São Francisco river and tributaries. It is found either sympatric with Cynolebias and other Hypsolebias of the group of the S.magnificus, or with that of the S.notatus, although it can also appear alone. As the distribution of this fish is both wide-spread and abundant, the physical and chemical characteristics of the water of its biotypes varies, thereby it appears to be capable of easily adapting to new environmental conditions. We have already found this species in pools with water which is clear or muddy, or of a whitish, reddish or greenish color, in forests, in transition regions, in pools totally exposed to light and in artificial pools. It is probably the most abundant species of Simpsonichthys in nature.

S. flagellatus recently collected. Photo: R. Suzart

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S.flavicaudatus, Costa and Brasil 1990.

Photo: M. Chauche

CLASSIFICATION: Description of two new fishes of the genus Cynolebias (Cyprinodontiformes: Rivulidae) from the São Francisco river basin, Brazil. Ichthyol. Explor. freshwaters 1: 15-22 ETYMOLOGY: From the Latin flavus = yellow and caudatus = with filaments on the tail fin. TYPE LOCALITY: The county of Lagoa Grande, state of Pernambuco, in the São Francisco river basin. SIZE: Males 55mm, females 48mm.

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BACKGROUND: Discovered in 1989, it was described in the following year. Several attempts have been made to introduce it into the hobby, but all in vain. CAPTIVE BREEDING: This fish is difficult to breed in captivity, and is only recommended to skilled fanciers. Even though a large amount of eggs are spawned at the same time, drying time is irregular, with eggs forming embryos and entering the diapause at different periods. Thus it is not difficult to encounter eggs from the same batch and substratum drying-date in different stages of embryonic development. HABITAT AND DISTRIBUTION: Besides the locality where it was discovered, there is a second known population in the county of Irece, around 150km further to the south, which in itself manifests very wide distribution. In the Irece site, it is encountered alone, whereas in Lagoa Grande it lives sympatric with C.albipunctatus in pools of whitish-colored water and with a clayey bottom.

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S.ghisolfii, Costa, Cyrino and Nielsen 1996.

Photo: J. Ghisolfi

Classification: Description d´une nouvelle espèce de Poisson annuel du genre Simpsonichthys (Cyprinodontiformes: Rivulidae) du basin du rio São Francisco, Brésil. Rev. Franç. Aquariol. 23:17/-20. Etymology: In honor of the fish-fancier, Julio Ghisolfi. Type locality: Guanambi county, in the state of Bahia, São Francisco river basin Size: The average size of the males reaches up to 50mm and of the females 38mm. Background: In january, 1996, we mustered a group of four people, André de Lucca, Álvaro Cyrino, José Carlos and myself, and set off towards the mid São Francisco

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river basin. The aim was to collect the recently described S.stellatus. We left São Paulo at nightfall and traveled all night until, on the next day and near to mid-day, we arrived at the town of São Francisco, already in the state of Minas Gerais, and the typical locality of our quest. After one whole day of collecting we encountered S.hellneri in a pool already known since 1991, besides C.perforatus, the most southerly known population of Cynolebias. Incidentally, there is every likelihood of this pool disappearing, because of its very nearness to the town. On the following day, we set out for Itacarambi, where we found more C.perforatus, S.hellneri, S.flagellatus and S.magnificus. On the beginning of the return trip, we decided to travel all night, in order to collect S.fulminantis and C.leptocephalus in Guanambi, Bahia. In the first pool, near to the town of Guanambi, we came across a large number of S.fulminantis, C.leptocephalus and a new species of Corydoras. Suddenly, a female fish of the S.antenori group, was netted, and immediately afterwards, some males. According to the color-pattern and due to the absence of any report on the presence of fishes of this group thereabouts, we perceived that we were dealing with a new species of Rivulidae. We began the long trip back without interruption. Guanambi is 1.500km from São Paulo. During the whole trip, a total of 3.400km, we had eight punctures, all of which caused considerable delay. Captive Breeding: S.ghisolfii is not a very easy fish to breed. On first being introduced into aquariums, attempts at breeding were unsuccessful. Fishes spawn well, but egg maintenance requires much care in relation to substratum humidity. It is not recommended for beginners. Habitat and Distribution: The distribution of S.ghisolfii is restricted to seasonal pools around the town of Guanambi, Bahia State. The pools follow the same pattern as those of the Brazilian semi-arid region, with a very clayey substratum, which makes collecting difficult, due to the ease in getting stuck. Plants such as Echinodorus sp. and Nimphea sp. are abundant. The water almost always presents a muddy whitish color, with a slightly alkaline pH between 7,1 and 7,2.

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S.igneus, Costa 2000.

Photo: M. Chauche.

CLASSIFICATION: Description of four new annual species of the genus Simpsonichthys (Cyprinodontiformes: Rivulidae) from the São Francisco and Paraná rivers basins, northeast and central Brazil. Aquarium 25: 8-15. ETYMOLOGY: In reference to the anal fin coloring in the males. TYPE LOCALITY: Igarité county, in the state of Bahia. SIZE: Males 45mm, females 41mm. BACKGROUND: Discovered in 1999, it was introduced as a hobby fish two years later, from a collection undertaken by André de Lucca. CAPTIVE BREEDING: This follows the same patterns as for the other species of the group. HABITAT AND DISTRIBUTION: It is able to be found in two pools close to the town of Igarité, in the state of Bahia, in the São Francisco river flood-plain. The water is dark-colored, with a depth of 60cm and abundant plant-life (Costa, 2000).

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S.janaubensis, Costa and Suzart 2006.

Draw: D. Nielsen

CLASSIFICATION: Three new species of seasonal killifishes of the Simpsonichthys antenori species group (Teleostei: Cyprinodontiformes: Rivulidae) from the São Francisco river basin, Brazil WILSON J. E. M. COSTA Zootaxa 1306: 2539 (2006) ETYMOLOGY: An allusion to the occurrence of the species in the region of the town of Janaúba. TYPE LOCALITY: Janaúba county, in the state of Minas Gerais. SIZE: Males 40mm, females 30mm. BACKGROUND: Discovered in 2002, it was only described in 2006. Up to now it has not been introduced as a hobby fish.

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CAPTIVE BREEDING: No information on its breeding is forthcoming, due to its not being a hobbyfish. HABITAT AND DISTRIBUTION: Two localities are known in seasonal pools in the Gorutuba and Verde Grande rivers flood-plains, Janaúba country, in the state of Minas Gerais. The pools were located in an area of the Caatinga, with an abundance of aquatic plant-life. In 2005, when on a second visit to the site, it was noted that the pool had been partially destroyed by urban outspreading of the town (Costa, 2006).

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S.macaubensis, Costa and Suzart 2006.

Photo: R. Suzart

CLASSIFICATION: Three new species of seasonal killifishes of the Simpsonichthys antenori species group (Teleostei: Cyprinodontiformes: Rivulidae) from the São Francisco river basin, Brazil WILSON J. E. M. COSTA. Zootaxa 1306: 2539 (2006) ETYMOLOGY: Name referring to the region of Macaúbas where fish is able to be found. TYPE LOCALITY: County of Macaúbas, state of Bahia. SIZE: Males 38,6mm and females 28,4mm. BACKGROUND: Discovered in 2003 by Rogério Suzart, it was introduced into the hobby as a new population of S.ghisolfii.

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CAPTIVE BREEDING: The first significant and perceivable difference to show that with this fish one is dealing with a species distinct from S.ghisolfii, was on observing its breeding, for it was found to be much easier to raise in captivity. Thus, initial distribution among aquarists was very rapid. HABITAT AND DISTRIBUTION: Known only in the typical locality, a road-side, seasonal pool, close to the town of Macaúbas, in the state of Bahia. Below, a photo of the totally dry habitat.

Photo: D. Nielsen

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S.mediopapillatus, Costa and Suzart 2006.

Draw: D. Nielsen

CLASSIFICATION: Three new species of seasonal killifishes of the Simpsonichthys antenori species group (Teleostei: Cyprinodontiformes: Rivulidae) from the São Francisco river basin, Brazil Wilson J. E. M. Costa. Zootaxa 1306: 2539 (2006). ETYMOLOGY: From the Latin medio (mid) and papillatus (with papillae), referring to the position of the neuromast in the central region of the head. TYPE LOCALITY: Pindaí county, in the state of Bahia. SIZE: Males 40mm, females 38mm. BACKGROUND: Discovered in 2002, it was only described in 2006 by Wilson Costa. Up to now it has not been introduced to fanciers. CAPTIVE BREEDING: No information on breeding is available, as the fish is not breed by aquarists. HABITAT AND DISTRIBUTION: This species is present in a flood-plain in the Rio Verde Grande basin, in the county of Pindaí, state of Bahia.

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S.flammeus Group Group formed by 07 species allocated in high and medium Tocantins and basin of Paracatu and Urucuia rivers, tributaries of São Francisco river. Color pattern similar to the group of the S.antenori but with bus in the males with coloration chestnut tree reddened. The females always present dark stain in the center of the body. Just S.delucai is found isolated the other species separately are found always with other species of Simpsonichthys. Cladograma with the phylogenetic relationship of the group S.flammeus (Costa, 2006).

S.delucai S.alternatus

S.multiradiatus

S.flammeus S.brunoi

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S.alternatus, Costa and Brasil 1994.

Photo: M. Chauche

CLASSIFICATION: Trois nouveaux poissons annuels du genre Cynolebias (Cyprinodontiformes, Rivulidae) du basin du rio São Francisco, Brésil. Revue Française d´Aquariologie 21 (1-2): 7-8, figure. ETYMOLOGY: This is in reference to the color-pattern of the males. TYPE LOCALITY: The county of Brasilândia de Minas, state of Minas Gerais. SIZE: Males 70mm, females 60mm. BACKGROUND: Discovered and classified in 1994, this fish specie was immediately introduced among aquarists and quickly became dispersed world-wide. At the time, it was assumed to be small-sized, but when on a trip in 1996, we came upon specimens up to 70mm long, very different from those at the time of discovery

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and which had previously served as a basis for classification, and were, on an average, only 25mm long. CAPTIVE-BREEDING: This fish is easy to breed in captivity. The eggs are incubated between 60 to 90 days when the substratum is very humid. From the first, newborn fry feed on salt-water Artemia naupilii or micro-worms. HABITAT AND DISTRIBUTION: Only the type locality is known, this consisting of a flooded area on the margin of the Paracatu River, close to the town of Brasilândia de Minas, in the state of Minas Gerais. On other trips to this specific area, various species of fishes from other groups, mainly Characins, were encountered. In years with heavy floods, only those fishes with permanent habits are able to be found, whereas annual fishes are absent. Water-color varied from crystal clear to whitish, depending on the year. Together with S.alternatus, we came across S.trilineatus, and, in a nearby foot-path, Riv.paracatuensis.

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S.brunoi, Costa 2003.

Draw: D. Nielsen

CLASSIFICATION: The Simpsonichthys flavicaudatus species group (Cyprinodontiformes: Rivulidae: Cynolebiatinae): phylogenetic relationship, taxonomic revision and biogeography. Ichthyol. Explor. freshwaters vol 14, nº1, pp.31-60, 17 figs. march, 2003. ETYMOLOGY: In honror of Bruno Bove da Costa. TYPE LOCALITY: Vila Boa county in the state of Goiás, flooded areas in the Ribeirão Canabrava basin. SIZE: Males 30mm, females 26mm. BACKGROUND: For three consecutive years, 2006, 2007 and 2008, trips to the locality were taken, in an attempt to find the species, but it was only discovered in february, 2008, in the type locality, sympatric with S.aff.notatus. This delay was brought about by the heavy rainfall in both 2006 and 2007, which in turn caused the level of the

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Cana Bravos river to rise, this propitiating the invasion by non-annual predatory fish, such as Hoplias malabaricus and other species of Characins, into the pool. The species was at once distributed among aquarists in Rio de Janeiro and São Paulo. Apparently, phylogenetically it is very closely related to S.flammeus, with slight osteological differences. CAPTIVE BREEDING: As described above, this fish has only recently been distributed among aquarists, and so far no information is available. Nevertheless, breeding habits probably follow the same course as those of S.flammeus. The water in the pool presented very low electric conductibility, near to zero, and an acid pH of 5.5. HABITAT AND DISTRIBUTION: Only the typical locality is known, where the fish is sympatric with S.aff. notatus. At the same spot, and besides these two species, brachoneta, crabs and a large number of aquatic insects were also present. In 2008, at the time of collecting, besides the two already mentioned fish, no other species was encountered in the pool, contrary to the two previous years, 2006 and 2007, when annual fishes were absent and fishes of permanent habitat were present.

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S.delucai, Costa 2003.

CLASSIFICATION: The Simpsonichthys flavicaudatus species group (Cyprinodontiformes: Rivulidae: Cynolebiatinae): phylogenetic relationship, taxonomic revision and biogeography. Ichthyol. Explor.freshwaters vol 14, nº1, pp.31-60, 17 figs. march, 2003. ETYMOLOGY: In honror of the Biologist and discoverer of the species, André de Lucca. TYPE LOCALITY: The county of Urucuia, in the state of Minas Gerais. SIZE: Males 20mm, females 16mm. BACKGROUND: After the discovery of S.trilineatus and S.alternatus in the Paracatu river basin, it was thought highly probable that we would also find species related to these in the Urucuia river basin. Stefen Hellner had already encountered S.similis in the mid Urucuia river, but there was a gap, the absence of a species of Simpsonichthys from the S.alternatus

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group in the Urucuia river basin itself. Several unsuccessfully trips were taken to the region, in the attempt to find a species related to the group S.alternatus. In 2001, when traveling around the region, André de Lucca came across a species related to S.alternatus, in the vicinity of the town of Urucuia, on the left margin of the Urucuia river. In 2003, we encountered one more population of S.delucai in an immense lake on the right margin of the Urucuia river. CAPTIVE BREEDING: This fish adapts easily to captivity and is easy to breed. Eggs hatch after around 70 days. Offspring are small at birth, and it is convenient to initially feed them on Paramecium and infusoria during the first few days. HABITAT AND DISTRIBUTION: The known typical localities are a pool on the left margin of the Urucuia river, and a large lake called Lagoa do “Cinqüenta” on the right margin of the same river. This lake was so-named after a legend in the region, telling of a woman farmer, a cattle raiser, who gave the order that whosoever contradicted her when taking cattle for her to buy, the person and all accompanying herders would be killed. In the legend it is stated that before being killed herself, she had already ordered 50 people to be murdered and thrown into the lake, thus giving origin to the name.

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S.fasciatus, Costa and Brasil 2006.

CLASSIFICATION: Three new species of the seasonal killifish genus Simpsonichthys, subgenus Hypsolebias (Teleostei: Cyprinodontiformes: Rivulidae) from the Paracatu river drainage and the São Francisco river basin, Brazil. Zootaxa 1244: 4155 (2006). ETYMOLOGY: From the Latin fasciatus - with vertical stripes, in reference to a male feature. TYPE LOCALITY: A seasonal pool in the Rio Preto basin, Unaí county, in state of Minas Gerais. SIZE: Male 19mm, female 16mm.

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BACKGROUND: Only recently discovered and classified, this species is closely related to S.alternatus. In a recent trip to the typical locality, we encountered a small pool near to the Rio Negro, with very dense vegetation and fishes of this species in abundance. Together, there were specimens of S.gibberatus, although in smaller number. CONDITIONS OF THE POOL: The maximum depth was 90cm, pH 4,9 and water temperature 23,90ºC. CAPTIVE BREEDING: It demonstrated the same breeding characteristics as S.alternatus, as well as being of a pacific and prolific behavior.

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S.flammeus, Costa 1989.

Photo: M. Chauche

CLASSIFICATION: Re-description of the genus Cynolebias (Cyprinodontiformes, Rivulidae), with the description of a species from the Tocantins river basin. Communication from the Science Museum of the “Pontífica Universidade Católica”, Rio Grande do Sul 2 (9): 185-189. ETYMOLOGY: From the Latin flammeus = shining, in reference to the color-pattern in the males. TYPE LOCALITY: Arraias county, in the state of Tocantins. SIZE: Males 33mm, females 28mm. BACKGROUND: Discovered and classified in 1989, it represents the first occurrence of Hypsolebias outside the São Francisco river basin.

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In the same year we encountered an additional population, when on a trip to another location more to the south of the type locality, this one on the margins of the Paraná river. This latter population is that from which specimens have been distributed to aquarists. Immediately on being distributed, it was a great success, due to its coloring and shape, and is being kept by fanciers world-wide. CAPTIVE BREEDING: This fish is relatively easy to breed in captivity only succumbing to Ichthyosis if the pH of the water becomes too acid. Eggs are incubated between 70 and 90 days. At birth, offspring can already receive naupilii, and at around 2 months they already begin to present sexual dimorphism. HABITAT AND DISTRIBUTION: Apart from the type locality, it is to be found more to the south, in the county of Nova Roma, in the state of Goiás, on the margins of the Paraná river, where it is encountered together with C.griseus and S.notatus. This pool was partially destroyed for the building of a bridge over the Paraná river and for 4 years fish were no longer encountered there. Nevertheless, this locality has since apparently recuperated its characteristics, and once again harbors plants and annual fishes.

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S.marginatus, Costa and Brasil 1996.

Photo: M. Chauche

CLASSIFICATION: Description d´une nouvelle espèce de poisson annuel du genre Simpsonichthys (Cyprinodontiformes: Rivulidae) du basin rio Tocantins, Brésil. Rev. Franç. Aquariol. 23: 93-96 ETYMOLOGY: From the Latin marginatus, in reference to the black line on the dorsal and anal fins of the males. TYPE LOCALITY: Barro Alto county, on the banks of the Rio dos Patos, a tributary of the Maranhão river, in the Tocantins river basin. SIZE: Males 28mm, females 22mm. BACKGROUND: Discovered in 1996 and classified in the same year, this species is living proof of the contribution of aquarists to the maintenance of threatened species. After the collection which originated its discovery, the fish-fancier Álvaro Cyrino

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received a couple. From this couple he managed to obtain some eggs and distribute them to other Brazilian aquarists, who, in turn, aided in spreading the species throughout the whole world. Thus, all the specimens in aquariums originated from this one single couple. CAPTIVE BREEDING: This fish is only recommended for skilled fish-fanciers, due to the small amount of eggs deposited by the couple, besides fry being born small and needing infusoria during the first days of life. Incubation of the eggs follows the same pattern as the other species of the group, around 50 to 75 days, at an environmental temperature of about 22ºC. HABITAT AND DISTRIBUTION: Only the typical locality is known, notably pools in gallery forest on the banks of the Rio dos Patos, a tributary of the Tocantins river, near to the locality of Barro Alto, in the state of Goiás. In a subsequent trip, it was noted that the locality had become an area for cultivating soya bean. As this is an area made up of uneven land, it is probable that the distribution of this fish is small, which leads to concluding that it is in grave risk of extinction.

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S.multiradiatus, Costa and Brasil 1994.

Draw: Ruud Wildekamp

CLASSIFICATION: Um Nouveau Poisson annual du genre Cynolebias (Cyprinodontiformes: Rivulidae) du basin du rio Tocantins, Brésil. Revue Française d´Aquariologie 21 (1-2):1-4, figures,map. ETYMOLOGY: Referring to the large number of rays on the dorsal fin, thus making it long. TYPE LOCALITY: The county of Brejinho do Nazaré, in the state of Tocantins. SIZE: Males 60mm, females 52mm. BACKGROUND: When on a trip in 1996, we came across the typical locality of S.multiradiatus in a pool inside a small-holding near to the Tocantins river. The pool, which was in a corn plantation, was very much altered and with a depth of up to 2 meters. It was only possible to collect on the edges. Only one male and three females were caught, all four appearing to be very old fishes.

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CAPTIVE BREEDING: As very few specimens have been collected, we have been unable to maintain the species in captivity, and without new collections, it did not endure among aquarists. HABITAT AND DISTRIBUTION: Only the typical locality is known, in the county of Brejinho do Nazaré in the state of Tocantins, in an altered and very much despoiled pool, due to this being in a corn plantation. Specimens of Trigonectes strigabundus, Maratecoara formosa and Plesiolebias xavantei were encountered together with S.multiradiatus.

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S.magnificus Group The males of this group of fishes present a gorgeous coloring. There are six recognized species in the Group: S.magnificus, S.fulminantis, S.hellneri, S.adornatus, S.picturatus and S.carlettoi. They were only encountered from 1990 on, their geographic distribution being intimately related with the São Francisco river basin. In almost all the localities, they are to be found sympatric with a species of Cynolebias, as well as another of Hypsolebias from the group S.antenori. Its known distribution accompanies the course of the São Francisco river, its southernmost limit being in a town of the same name, São Francisco, in the state of Minas Gerais, and its northernmost in the vicinity of a town called Xique Xique, in the state of Bahia. Phylogenetic relationship of the group (Costa, 2006):

S.hellneri S.adornatus S.fulminantis S.carlettoi S.magnificus

S.picturatus

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S.adornatus, Costa 2000.

Photo: M. Chauche

CLASSIFICATION: Description of four new annual species of the genus (Cyprinodontiformes: Rivulidae) from the São Francisco and Paraná river basins, northeast and central Brazil. Aquarium 25: 8-15. ETYMOLOGY: From the Latin adornatus - that which adorns, in reference to the long base of the male dorsal fin. TYPE LOCALITY: County of Sítio do Mato, in state of Bahia. SIZE: Males 46mm, females 36mm. BACKGROUND: Discovered in 1999, in the middle São Francisco river basin. Due to its beauty and shape, it at once became popular among aquarists.

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CAPTIVE BREEDING: This fish is rather difficult to breed in captivity, but due to its beauty and unique shape, it is a fish-fancier’s favorite. The eggs incubate between 75 and 90 days, although this could reach 100, depending on environmental temperature. Good-sized fry are born, which immediately begin to feed on artemia naupilii. HABITAT AND DISTRIBUTION: Known only from the typical locality, they inhabit seasonal pools in the São Francisco river flood-plains, near to the town of Sítio do Mato, in the state of Bahia. It is to be found together with C.gibbus, in pools with abundant plant-life, mainly Nynpheas sp.

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S.carlettoi, Costa and Nielsen 2004.

Classification: Simpsonichthys carlettoi (Cyprinodontiformes: Rivulidae) a new annual fish from the São Francisco river basin, north-eastern Brazil. Wilson J. E. M. Costa and Dalton T. B. Nielsen. Aqua, Journal of Ichthyology and Aquatic Biology, vol 8 nº3-2004 Etymology: In honror of the aquarist André Carletto. Type locality: Guanambi county in the state of Bahia. Size: A small-sized fish, males reaching a maximum size of 50mm. Background: When on a field-trip in january, 2002, André Carletto and I decided to pass through the region of the mid São Francisco river basin, in the state of Bahia. Collecting conditions were very much prejudiced that year, due to the lack of

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rain. In addition, the very bad state of the roads made the task an adventure with little to report. On beginning of our return trip to São Paulo, we headed east to the town of Guanambi, leaving the São Francisco river behind us. Near to the town, we came across a small pool about 50m wide, the depth not going beyond 50cm. The pool was being used as a watering-place for cattle, and there was a barbed wire fence in the middle. At the first attempts, we caught a fish with a different coloration from all those known to that date. In the beginning we thought we were dealing with S.fulminantis, then S.magnificus. Finally we came to the conclusion that this was a new species, although there were few specimens at hand. Together in the pool, we encountered specimens of another species of Simpsonichthys from the S.antenori group. In january, 2006, we were once again at the locality which was then dryer. Even so, S.carlettoi, a species from the group of S.antenori, were very much in abundance, together with a species of Cynolebias, probably Cyn. Leptocephalus. Once in the aquarium, differences became more precisely noted, mainly as regards coloring, and the fact that males anal and dorsal fins were pointed, contrary to those of S.magnificus, which are rounded. Captive Breeding: S.carlettoi proved to be a much more prolific species than others of its group. However, in the first hundred fry born, disparity in sex was very great, as only three of the offspring were females. Unfortunately, although several hundreds of fry were obtained in the second generation, nobody managed to acquire even a sole female! Over the following years, further specimens were collected from the same site and distributed to additional aquarists who were successful in keeping the species in captivity. Habitat and Distribution: Only the typical locality is known, a small seasonal pool near to the town of Guanambi, Bahia State, in a flood-plain of the Rio das Rãs. The water of the pool is of a whitish color, there is a clayey substratum and plant-life is not very abundant, with a predominance of Echinodorus sp. The pH is perceptibly over 7,0. Below, Didier Pillet gives a description of experience in captive-breeding

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with this species and of attempts at crossbreeding with S.magnificus and S.fulminantis. Breeding: After courtship, the male leads the female into the substratum, where they hide so as to liberate and fertilize numerous small eggs. For spawning I used a 10x10x12cm plastic box, with a 4 to 5cm layer of substratum on the bottom. There is a lid to the box, drilled with a 2 to 3cm hole. Incubation: For a batch of around 40 eggs (F1), a first hydration after 35 days of incubation, at a temperature of around 26°C, resulted in 17 fry. A second hydration after 66 days of incubation produced 10 more new fry, and a third after 165 days, 10 more. The raising of a second generation confirmed these results. On scanning F3 offspring, I noted that, contrary to what had been observed in other species whose mature embryos can withstand 3 or 4 months in the turf without any problem, it appears to me that mature eggs of S.carlettoi cannot resist a long dry-wait. In order to obtain good-quality fry, it is important to moisten the eggs every fortnight after the first month of incubation. Feeding: Immediately after birth, I usually give infusoria. On the second day, fry eat naupilii. As is the case for all Simpsonichthys, it is better to give live food, although it is possible to accustom them to dry meal or frozen food. Maturity: With correctly nourished fry, males begin to develop colors after one month. After two months they begin to breed. Attempts to crossbreed: Their similarity to S.fulminantis and the geographic proximity of the two fishes made me curious. Why not try to breed hybrids? Simultaneously, I also tried crossing with S.picturatus and S.magnificus. The same procedure was used in the three attempts: the couple is separated

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for 7 days in a five liter aquarium, with a bottom- covering of coconut fiber. Cross-breeding of male S.picturatus with female S.carlettoi The behavior is the same of inter-specific breeding. On january 3rd, 2006, after one week together, the couple was separated. Approximately 50 eggs were collected and accounted for. The eggs were placed into an incubator, with the temperature varying between 25 and 27°C. On february 10th, eggs that appeared to be fertilized were checked. Generally, unfertilized eggs either turn white after 2 or 3 days or simply disappear. On april 2th, around 50% of the fertilized eggs had disappeared, only 25 remaining. Two checks on may 11th and june 2th, done without counting, indicated no embryo development. In time, these residual eggs gradually disappeared. On july 18th, only 13 stage ¼ eggs remained Further observations did not permit noting embryonic eggs, and finally all had disappeared. Cross-breeding of male S.magnificus with female S.carlettoi The behavior is the same of inter-specific breeding. On february 10th of 2006, after a week together, the couple was separated. A batch of 12 eggs was selected and separated into a plastic bag, and the remainder placed into a plastic box. The eggs were put into an incubator, with the temperature varying between 25 and 27°C Observations: . 02/04/06, count of 11 eggs in the ¼ stage. . 11/05/06, count of 9 eggs in the ¼ stage. . 03/06/06, count of 4 eggs in the ¼ stage . 18/07/06, count of 2 eggs in the ¼ stage Further observations did not reveal embryonic eggs, and finally all had disappeared. Cross-breeding of male S.fulminantis 

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150 with female S.carlettoi

The behavior is similar to that of inter-specific breeding. On january 22th of 2006, after being one week together, the couple was separated. A batch of 14 eggs was selected and separated into a plastic bag. The rest was put into a plastic box. The eggs were placed in an incubator, the temperature varying between 25 and 27°C. Notes: . 10/02/06, count of 11 eggs in the ¼ stage, in the plastic bag. . 13/03/06, count of 9 eggs in the 4/4 stage in the plastic bag. . 02/04/06, hydration of the whole collection (plastic bag and box). A count of 19 fry after 24 hours. Unfortunately there were only male offspring, and so it was impossible to continue this test with F2. Conclusion: Crossbreeding S.picturatus with S.carlettoi and crossing S.magnificus with S.carlettoi did not produce feasible embryos. Only the S.fulminantis x S.carlettoi cross was fertile. The absence of females did not permit continuing the experience into other generations. We point out that the S.fulminantis male used in this experiment came from a generation that had only produced males.

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Hybrid from S.fulminantis and S.carlettoi Photo: Didier Pillet

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S.fulminantis, Costa and Brasil 1993.

Photo: M. Chauche

CLASSIFICATION: Two new species of Cynolebias (Cyprinodontiformes: Rivulidae) from the São Francisco river basin, Brazil, with notes on the phylogeny and biogeography of annual fishes. Ichthyological Exploration of Freshwaters 4 (3): 194-196, figures 1-2, maps. ETYMOLOGY: In reference to the color-pattern of male fins. TYPE LOCALITY: Guanambi county, in the state of Bahia. SIZE: Males 42mm, females 36mm. BACKGROUND: Discovered in 1992, together with C.leptocephalus, it is one of the most beautiful of the Simpsonichthys species. Nowadays it is distributed among all groups of killifish fanciers.

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CAPTIVE BREEDING: This fish is relatively easy to breed in captivity. It is only necessary to take care with birth disparity between males and females. Certain devices are advisable, such as leaving the water slightly alkaline and separating the fry into small aquariums, two to each. Eggs hatch between 70 and 90 days, and fry already accept naupilii from the first. HABITAT AND DISTRIBUTION: It is can be found in several seasonal pools near to the town of Guanambi, in Bahia, as well as in a locality in the São Francisco river flood-valley to the south of another town, Bom Jesus da Lapa. In 2006, a new population with different characteristics was discovered at a spot to the east of Bom Jesus da Lapa. This population present a different colorpattern and is being analized to verify whether it is a distinct species.

Photo: R. Suzart

It is generally sympatric with C.leptocephalus and S.ghisolfii in Guanambi, and C.gilbertoi, S.flagellatus, and C.attenuatus, in the São Francisco floodplain. The pools are, at the maximum, 60cm deep, with a very clayey substratum, which gives the water a whitish color. In Guanambi, besides encountering other species of Rivulidae, we found one species of Corydora sp. and two species of Characins in one of the sites.

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S.hellneri, Berkenkamp 1993.

Photos: M. Chauche

CLASSIFICATION: Ein neuer Fa cherfisch aus dem Bundesstaat Minas gerais, Brasilien, Cynolebias hellneri sp. n. das Aquarium 27 (290):8-15, figures, map. ETYMOLOGY: In honror of the collector of the species Steffen Hellner. TYPE LOCALITY: A roadside pool between the towns of Itacarambí and Manga, in the state of Minas Gerais, São Francisco river basin. SIZE: Males 50mm, females 32mm.

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BACKGROUND: The species was discovered in april, ’92 by the aquarist Steffen Hellner and classified in the following year. In the same year I came across it, near to the town of São Francisco. CAPTIVE BREEDING: It is recommended to those possessing a little more skill in breeding annual South-American killifishes. HABITAT AND DISTRIBUTION: The most northerly known population is located close to the town of Malhada, situated in the state of Bahia already, whereas the most southerly one is to be found near to the town of São Francisco. All these populations are located along the Sao Francisco river, in a strip approximately 200km long. Near to the town of Itacarambí, the populations have a more exuberant coloring, whereas at the extremities of geographic distribution the colors of the fishes are less intense. Only the São Francisco population is encountered alone, without the presence of any other species of Rivulidae. Otherwise it is always to be found together with S.flagellatus and C.perforatus, and in Itacarambí with S.magnificus.

A recently collected S.hellneri at the limit of its southerly distribution, near to the town of São Francisco, state of Minas Gerais.

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S.magnificus, Costa and Brasil 1991.

Photo: Dalton Nielsen. From the Itacarambí population.

Classification: Three new species of Cynolebias (Cyprinodontiformes: Rivulidae) from the São Francisco river basin, Brazil, Ichthyological Exploration of freshwater 2 (1): 59-60. Etymology: From the Latin magnificus, alluding to the exuberant colors of the males. Type Locality: The county of Manga, north Minas Gerais State, around 1km from the São Francisco river. Size: There is a population near to the small town of Gado Bravo, where males measuring up to 65mm and females 58mm long, were encountered. Background: I was one of the first to have the privilege of seeing one of the most beautiful species of Simpsonichthys. The news of its discovery spread rapidly among Brazilian aquarists, and at once everybody wanted to see and possess this

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resplendent fish. I took a collecting trip to the São Francisco region, together with André Carletto, Ruud Wildekamp and Dale Weber, only three years later, in 1993. On this trip we came across the species a little further south, in the county of Itacarambí, Minas Gerais State. Together, in the same spot, we also found S.flagelatus, S.hellneri and Cyn.perforatus. On returning to São Paulo, we distributed the species among Brazilian and foreign aquarists, it soon becoming common everywhere. Captive Breeding: This fish is slightly more difficult to breed in captivity due to the different stages in embryo development. After a period of around 60 days, during which the substratum is drying, the aquarist should place this in water and await the appearance of the fry. After 4 days, the substratum should be allowed to dry once again for a further fortnight. Following this, it should once again be placed in water to await the birth of a second generation. This procedure could possibly repeat for up to 4 times with the same batch of eggs. Males try to establish small territories and defend them by threatening displays to others attempting to invade. Real confrontation are rare. Females pass freely through territories, and between one display and another, the males induce those females in their territory to spawn, as a clear demonstration towards other males of territorial dominion. After spawning, the males once again return to checking the frontiers of their territories. Another likelihood is the larger the territorial area the greater the probability of mating. Habitat and Distribution: Over the following years, I took several further trips to the São Francisco river basin, whereby it was possible to more precisely define the geographic distribution of this species. We encountered it in several pools in the Rio Verde basin, as well as in the state of Bahia, close to the town of Malhada. The Itacarambí locality, situated on the road-side, was destroyed when the BR-135 highway was asphalted, but the populations located near to Gado Bravo and that of Malhada are well-conserved.

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Pools have cerrado characteristics, with a water temperature that varies between 21°C a 25ºC, remaining even hotter as the pool dries up. The pH is neutral, tending to acid with total hardness and carbonated always at zero. The aquatic plant-life of the pool is abundant, and on the margins there are middle-sized bushes and small trees. These trees give shade to a large part of the pool. We also encountered several species of aquatic insects, besides Branchonetas and tadpoles, very common in annual fish pools. Description of the species by Rogério Suzart in 2005 The species really received a name that suits the colors of the males. The body is almost entirely composed of a vivid pink color, tending to a wine-red or dark-red in some spots such as on the back and fins. The whole body is covered by scales which form well-defined rows from the head to tail fin, presenting an intense sky-blue reflex, varying to a scintillating green and, at times, a golden tone. Their dorsal, anal and tail fins present the same color pattern as the body, although with stronger colors, their extremities being marked by a black edge, more present in some males than in others, mainly when the males are displaying in courtship or to other males. The iridescent spots that occur in scales all over the animal’s body, become transformed into horizontal stripes on the fins, this in a much more organized way than in the body configuration, normally forming 3 distinct and well-defined horizontal lines and stripes on the dorsal fin and 4 lines on the anal fin. The pectoral fins are pink and the pelvic ones red with a yellow base. The eyes are crossed by a reddish vertical band and the opercular region is yellow with a greenish reflex. On writing on the morphology of this species and checking the photos taken of the different populations of Gado Bravo-MG and Malhada-BA, I observed certain subtle differences in the color and shape patterns of the fins among the populations. In the following table there is a discrete analysis of these differencis, but nevertheless visually identifiable, variations:

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POPULATION A: Gado Bravo - POPULATION B: Malhada

Photos: R. Suzart.

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160 Aspect Observed

Population “A”

Population “B”

Format of the Dorsal and Anal

Tapering posterior extremities,the last rays prolonging and forming a 90°angle

Reunded extremities

Coloring of fin Dorsal and Anal

Blue,green and/or yellow reflexes on extremites

Extremity edge dark

Dorsal and Anal fin iridescent stripes

First half horizontal and second half transversal up to the posterior extremity

Horizontalfrom the anterior to posterior extremity

General Body Coloring

Coloring tending to milky (as with Simpsonichthys carlettoi)

Vivid and more accentuated colors

Females: The females are a little smaller than the males, being from 2 to 4cm, and as with all representatives of the genus Simpsonichthy, they do not present outstanding colors. They are simply a standard yellowish-brown with a weak bluish reflex, visible only when the animal is exposed to strong light. Furthermore, they show one or more irregular patches in the form of black ocelli on the abdominal parts. The fins are completely transparent, whereas the eyes present the same reddish vertical stripe that occurs in the males, although the coloring is faded.

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S.picturatus, Costa 2000.

Photos: M. Chauche.

CLASSIFICATION: Description of four new annual species of the genus Simpsonichthys (Cyprinodontiformes: Rivulidae) from the basins of the São Francisco and Paraná rivers, northeastern and central Brazil. Aquarium 25: 8-15. ETYMOLOGY: From the Latin picturatus - adorned with dots, a reference to the male color pattern. TYPE LOCALITY: Volta das Pedras county in the state of Bahia.

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162 SIZE: Males 45mm, females 36mm.

BACKGROUND: Discovered in 1999 and described in 2000, this very beautiful species is closely related to S.magnificus. It was introduced among aquarists in 2002, and spread at once. CAPTIVE BREEDING: It proved to be a much easier species to breed than S.magnificus, with less time for incubating eggs (around 60 days). HABITAT AND DISTRIBUTION: Apart from the typical locality, two more sites are known, one in Vista do Lagamar and the other in Bom Jesus da Lapa. The most southerly site known is around 60km from the type locality. The species was encountered in a pool in the caatinga region, together with S.flagellatus and Cyn.altus. Collection was done at two different times, february and may (Costa, 2000). In february, specimens of both S.flagellatus as well as C.altus were numerous, whereas of S.picturatus were rare, these only being found in spots in the pool with abundant plant-life. After the first collection, there was a dry period followed by a rainy one. These dry periods during the rainy season are known as “Indian Summers”. Three months later and in the same site, S.flagellatus and S.picturatus were abundant, whereas C.altus was completely absent. This suggests that the latter possesses an annual life-cycle distinct from Simpsonichthys species, with eggs hatching in the beginning of the rainy season, but incapable of doing so after the “Indian Summer” (Costa, 2000). On the other hand, a large number of eggs from the Simpsonichthys species hatched after only a short period without rain. This was later proved in the aquarium.

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S.notatus Group A group formed by 11 known species: S.notatus, S.rufus, S.nielseni, S.stellatus, S.similis, S.radiosus, S.ocellatus, S.gibberatus, S.auratus, S.trilineatus and S.virgulatus. Their distribution is concentrated in the middle São Francisco river basin, the Paracatu river basin, the upper Paraná river basin and the Pato river, a tributary of the Tocantins river. Species are found in the states of Minas Gerais and Goiás. The case of many biotypes, species are encountered sympatric with species of Simpsonichthys from the group S.antenori: - S.notatus is found together with S.flammeus and S.brunoi. - S.trilineatus is discovered together with S.alternatus. - Near to the town of São Francisco, in Minas Gerais, S.stellatus is met with in the company of Cyn.perforatus, this population defining the northernmost limit of distribution of S.stellatus besides the southernmost limit of distribution of the genus Cynolebias. Cladogram of the group’s phylogenetic relationship (Costa, 2006):

S.rufus S.similis S.notatus S.radiosus S.stellatus S.nielseni S.trilineatus S.auratus

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S.auratus, Costa and Nielsen 2000.

Photo: M. Chauche.

CLASSIFICATION: Simpsonichthys auratus, a new annual fish from the Paracatu river drainage, São Francisco basin, Brazil (Cyprinodontiformes, Rivulidae). Ichthyol. Explor. Freshwaters 11:7-12. ETYMOLOGY: Referring to the male coloring, from the Latin auratus/golden. TYPE LOCALITY: A seasonal pool on the margin of the Taboca river, in the county of Lagoa Grande, state of Minas Gerais. SIZE: Males 32mm, females 23mm. BACKGROUND: In march, 1996, I entered in contact with André Carletto, for us to go collecting in the Paracatu river basin, in Minas Gerais State. Our main aim was to collect S.trilineatus and S.alternatus, and to maybe find other species of

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Simpsonichthys or Cynolebias. We fixed the trip for the beginning of april. I was worried about the weather, 1996 was a year of little rain. The distance between my home in São Paulo and the region of the Paracatu river is not very far, around 1000km all told, we made use of a friday holiday and left very early. On the same day, at around 3p.m., we were already near to the basin. First we made many attempts to collect near to the Rio da Prata (a tributary of the Paracatu river), but the region was really very dry, and there were not many appropriate environments for Simpsonichthys. We decided to disperse a little and went towards a village called Lagoa Grande. It was already getting dark when we crossed a small bridge over the Taboca river and at once came across a small pool. We stopped the car and, picking up the small conical nets, we began the collection. I was a little doubtful about finding any Rivulidae there, as it was very near to the river, but already on the first attempt we caught a beautiful specimen of a Simpsonichthys of a type we had never seen before, with an indescribable yellow-gold coloring. Until the year 2000, S.auratus had been considered as a population of S.trilineatus, and it was only in this year and with better preserved material, that we were able to distinguish the differences between the species and elaborate the appropriate descriptive work. In 2003 I returned to the spot, only to find it partially destroyed as a result of building a detour for the road, this passing through the pool, splitting it in half. The amount of fill-in used had suffocated the aquatic plants, leaving behind a very bad-quality water. After five hours of trying to find fishes, we collected only five specimens. I was very worried, as this was the only known population of S.auratus. In 2005, on a return trip in the company of Francisco Falcon and Bruno Gaffino, we re-encountered the Biotype completely recovered, with re-composition of the aquatic plant-life and a large number of fishes. CAPTIVE BREEDING: These fishes quickly adapt to aquarium conditions and prove to be very sickness-resistant. As I had in my possession a great number of fishes, I obtained a large amount of eggs. I placed around five couples in a 50 liter aquarium with turf on the bottom. I dried the turf for around 60 days. After incubation, I placed the eggs in

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water, whereupon many offspring, about 3mm long, were born. Everything led to believe that this appeared to be an easy species to breed. Nevertheless, the number of males born in relation to the number of females was disproportional. Of the 86 fry born, only two were females, this occurring with all breeders to whom I had distributed the fish. In the beginning, offspring appeared to be all females, as they presented dark patches on the body, but as they continued growing, they acquired male characteristics. For all those who appreciate South American killifishes, they absolutely cannot fail to have this fish, as it really is one of the most beautiful of all the known species, with a different color pattern from the remaining Simpsonichthys. HABITAT AND DISTRIBUTION: Distribution is limited to the type locality. This is a seasonal pool on the margins of the Taboca River, in the county of Lagoa Grande, Minas Gerais State. The maximum depth of the pool is 1,20mm, with a width of around 6 meters and a length of about 10 meters. The pH of the dark-colored water is neutral, and the plant-life very dense, with a predominance of Ultricularia sp.

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S.gibberatus, Costa and Brasil 2006.

Photo: Didier Pilet.

CLASSIFICATION: Three new species of the seasonal killifish genus Simpsonichthys, subgenus Hypsolebias (Teleostei: Cyprinodontiformes: Rivulidae) from the Paracatu river drainage, São Francisco river basin, Brazil. Zootaxa 1244: 4155 (2006). ETYMOLOGY: From the Latin gibberatus backward curved, an insinuation of the lateral profile of the antero-dorsal dislocation in the female body. TYPE LOCALITY: The county of Unaí, state of Minas Gerais, Rio Preto flood-plain, Paracatu river basin. SIZE: Males 30mm, females 27mm.

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BACKGROUND: This species was recently discovered and described, together with S.fasciatus and S.virgulatus. We ran across it in march, 2007, near to the typical locality and in a small pool crowded with aquatic plants, which made collection quite difficult. One of the problems that we came across with, was in identifying the females, which are very much like females of S.fasciatus. When adapted to the aquarium, they disclosed a beautiful greenish coloring. CAPTIVE BREEDING: The first impressions regarding the breeding of this species revealed that males are very territorial, even in relation to females, these preferring to stay hidden while the males dominate the aquarium. Nevertheless, they appear to be very prolific. In only 25 days, a couple managed to spawn more than 300 eggs (Statement of Didier Pillet). Two aquariums were placed side-by-side, each containing a couple. The males often displayed when one perceived the other, thus demonstrating the desire to defend its territory. HABITAT AND DISTRIBUTION: Only the typical locality is known, where S.fasciatus is also to be found. The pool is small-sized, measuring approximately 20m2 and with a maximum depth of 40cm. The water was clear-colored, with a pH of 5.7, an air temperature of 29°C, a water temperature near to the surface of 23.1°C and a water temperature near the bottom of 20.8°C. Other sympatric fish species were Astyanax sp, Characidium sp. and Synbranchus sp.

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S.nielseni, Costa 2005.

Photo: Didier Pilet.

CLASSIFICATION: Simpsonichthys nielseni sp. n. (Teleostei: Cyprinodontiformes:Rivulidae): a new annual killifish from the São Francisco river basin, Brazil. Zootaxa 1039: 5764 (2005). ETYMOLOGY: In honor of its discoverer Dalton Tavares Bressane Nielsen. TYPE LOCALITY: A temporary pool in the county of Pirapora in the state of Minas Gerais. SIZE: Males 40mm, females 32mm. BACKGROUND: In february, 1998, I left the city of São Paulo and headed for the São Francisco river in the state of Minas Gerais, together with Roberto Zucchini and Carlos Roberto. The plan was to meet up with two friends from Belo Horizonte, Toninho

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and Juliano in the town of Pirapora, on the margins of the São Francisco river. We arrived at Pirapora one day before that combined with the friends from Belo Horizonte. As we had time to spare, we went for a walk in the town. On doing so, we came across an enormous lake approximately 4km wide inside the town itself. The lake was used for discharging rubble and trash. I decided to try to sieve the water, and at once there appeared several specimens which we took to be S.stellatus. The place was very much polluted, so we soon gave up trying to continue collecting for fear of catching some sickness. On the following day, we met up with Juliano and Toninho, and together continued the trip, heading north and following the São Francisco river. We did not give much value to the fishes, for they were very young and with little coloring. In the preceding year, in 1996, I had collected several specimens of Simpsonichthys in a spot near to Ibiaí, which, in 2001, were described as being S.rufus. Since then, the population of Pirapora is now considered to be of this same species. I returned to the place only in 2005, when we encountered the lake in a good state of conservation. Rubble and trash were no longer being thrown into it, and the quality of the water was very good, with a pH of around 6.8, total DH equal to zero and a water temperature of 26ºC. On this occasion, I collected adult fishes, with well-defined coloring and color patterns. I could then check the differences among this typical population of S.rufus. CAPTIVE BREEDING: Captive breeding of this species follows the same patterns as those of other Simpsonichthys , with a relatively short incubation period of around 45 to 60 days, and an average environmental temperature of about 24ºC. At birth fry already feed on Artêmia Salina´s Naupilii. In approximately the third month, fishes already began to present sexual dimorphism. HABITAT AND DISTRIBUTION: Only the typical locality in Pirapora, Minas Gerais is known, this consisting of a large pool which in certain parts reaches two meters deepth. The color of the

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water is clear and there is abundant aquatic plant-life.

The site in Pirapora where S.nielseni occurs.

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S.notatus, Costa, Lacerda and Brasil 1990.

Photo: M. Chauche.

CLASSIFICATION: Description de deux nouvelles espèces du genre Cynolebias du basin du rio Tocantins (Cyprinodontiformes, Rivulidae). Revue Française d´Aquariologie 17 (1): 10-11, figures 1-2. ETYMOLOGY: Referring to the dark spot in the center of the body of the male. TYPE LOCALITY: Indicated as a seasonal pool on the margins of the Paraná river, in the Tocantins river basin, located in the county of Alvorada do Norte, Goiás State. SIZE: Males 32mm, females 23mm. BACKGROUND: In 1989, during a short and very fruitful trip to the Paraná river basin in northeastern Goiás, I came across 3 species as yet unheard of among aquarists, two of them, up to that moment, even unknown by science, namely S.notatus e

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Cyn.griseus. CAPTIVE BREEDING: This fish is relatively difficult to breed in captivity. Eggs complete development in between 60 to 75 days, at an average temperature of 24ºC. HABITAT AND DISTRIBUTION: Besides the typical locality, this species has already been found in two other sites, one on the road between Flores de Goiás and Iaciara, and the other more to the south and close to the town of Vila Boa. In the typical locality, it is encountered together with S.flammeus and Cyn.griseus, on the road between Flores de Goiás and Iaciara it is found alone, and near to the town of Vila Boa, it is sympatric with S.brunoi. In the typical locality, the water is of a whitish color and the substratum composed of white clay. S.flammeus and C.griséus are more present in the center of the pool and S.notatus more abundant in the shaded areas.

Photo: Francisco Falcon.

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S.ocellatus, Costa, Nielsen and de Lucca 2001.

CLASSIFICATION: Four new annual rivulidae of the genus Simpsonichthys (Cyprinodontiformes) from the basins of the São Francisco and Pardo rivers, Brazil. Aquarium 26:2431. ETYMOLOGY: Referring to the eye-like spot on the female’s body. TYPE LOCALITY: Itaobim county, in the Jequitinhonha river plain-valley, both in the state of Minas Gerais SIZE: Males 37mm, females 24mm. BACKGROUND: In the year 2000, during a trip to the state of Bahia, the vet Arsênio Baptista and I, while passing through the Jequitinhonha river basin, caught sight of a flooded region with a large amount of aquatic plant-life. We decided to investigate the area

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although with little hope, seeing that attempts to collect in this specific basin had already been taken, but without success. At the first endeavors, a new species of Simpsonichthys appeared in the net. This was the first occurrence of a species of Rivulidae in this basin. CAPTIVE BREEDING: Due to its modest coloring, few aquarists showed interest in keeping this species in captivity. Consequently, little has been reported on its breeding. Apparently this is a relatively difficult species to raise, and so is recommended to those with a certain skill. HABITAT AND DISTRIBUTION: On further trips to the region, several additional populations of S.ocellatus were discovered along the Jequitinhonha river basin. The pool itself was shallow, being around 30cm deep and 250 meters wide. The water was clear, although slightly brownish, with an abundant aquatic plant-life, which included Echinodorus sp. e ultricularia.

The habitat of S.ocellatus.

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S.radiosus, Costa and Brasil 2004.

.

Draw: Ruud Wildekamp.

CLASSIFICATION: Simpsonichthys radiosus sp. n. (Teleostei: Cyprinodontiformes: Rivulidae): a new annual killifish from the upper Tocantins river basin, central Brazil. Zootaxa 737: 17 (2004) ETYMOLOGY: A reference to the color pattern of the males tail fin. TYPE LOCALITY: Formosa county in the state of Goiás, in flooded areas on the margins of the Crixás river, a tributary of the Paranã river, in the Tocantins river basin. SIZE: Males 25mm, females 23mm. BACKGROUND: As this species has only recently been discovered and described, no information besides the working description was unearthed.

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CAPTIVE BREEDING: No information on breeding has been acquired so far. HABITAT AND DISTRIBUTION: Only the typical locality is known. The pH of the water is alkaline, between 7,2 and 8,0 (Costa e Brasil, 2004).

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S.rufus, Costa, Nielsen, and de Lucca 2001.

Draw: Ruud Wildekamp.

CLASSIFICATION: Four new annual rivulids of the genus Simpsonichthys (Cyprinodontiformes) from the São Francisco river and Pardo river basins, Brazil. Aquarium 26:24-31. ETYMOLOGY: In reference to the color of the male which in Latin is rufus - red. TYPE LOCALITY: The county of Ibiaí, in the state of Minas Gerais. SIZE: Males 33mm, females 26mm. BACKGROUND: On a trip which I took together with my wife Norma A. P. S. Nielsen, in 1997, we took the road which links the BR-365 Highway to the town of Ibiaí, close to the Rio do Barro, where we encountered specimens of S.rufus in two sites one near to another.

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This species is closely related to S.nielseni e S.stellatus, but differs therefrom by its intense reddish pattern. CAPTIVE BREEDING: Slightly difficult for beginners, as fry are rather small-sized at birth, whereby feeding with infusoria and paramecium is recommended during the first week. HABITAT AND DISTRIBUTION: There are three known pools, very near one to another, all three subject to human interference, on the BR-365 Highway to Ibiaí. These are pools with an abundant plant-life, where we only found S.rufus.

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S.similis, Costa and Hellner 1999.

CLASSIFICATION: Simpsonichthys similis (Cyprinodontiformes, Rivulidae), une nouvelle espèce de poisson annuel du basin du rio São Francisco, Brésil. Ver. Franç Aquariol. 25: 89-91. ETYMOLOGY: In reference to the color pattern of the male, similar to that of S.notatus. TYPE LOCALITY: Flood-plain of the Urucuia river, in the county of Urucuia, state of Minas Gerais. SIZE: Males 35mm, females 28mm. BACKGROUND: First collected by the German aquarist Stefen Hellner in 1995, it was only considered a new species in 1999. Phylogenetically, it is very closely related with S.stellatus. After initial collection, the locality was no longer to be found, even after several trips to the region. CAPTIVE BREEDING:

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Widely distributed among European aquarists, it presents the same breeding pattern as S.stellatus. HABITAT AND DISTRIBUTION: Apart from the typical locality in the Urucuia river flood-plain, located in the county of Urucuia, state of Minas Gerais, in 1997 we encountered a new population, also in the same flood-plain, but closer to the town of São Romão. This population was introduced to fanciers as S.sp. Urucuia, although complementary studies are still necessary to check whether this is a distinct species or not.

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S.stellatus, Costa and Brasil 1993.

Draw: Ruud Wildekamp.

CLASSIFICATION: Trois nouveaux poissons annuels du genre Cynolebias (Cyprinodontiformes, Rivulidae) du basin du rio São Francisco, Brésil. Revue Française d´Aquariologie 21 (1-2): 7-8, figure. ETYMOLOGY: From the Latin stellatus starry, a reference to the iridescent dots on the male. TYPE LOCALITY: Near to town of São Francisco, in the state of Minas Gerais. SIZE: Males 39mm, females 28mm. BACKGROUND: Discovered in 1994, it was quickly introduced to aquarists and successfully breed. CAPTIVE BREEDING: This fish is not recommended for beginners, as it is relatively difficult to breed, but only for those with wide experience. Generally there are problems

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when sexing, due to the possible disproportion between males and females from the same clutch. HABITAT AND DISTRIBUTION: The locality where it was found in São Francisco is probably the northern limit of its distribution, and the only one where it is to be found with two other species of Rivulidae, namely S.flagellatus and C.perforatus. This is also the known southern limit of distribution of the two latter species. Distribution extends throughout the São Francisco river flood-plain to the south of the town of São Francisco, until a site in Bonfinópolis de Minas, where there are several pools with this species on both margins of the river. Elsewhere, in the other localities, they are to be found alone, without another species of Rivulidae. There is one species distributed among aquarists, S. sp urucuia and another recently discovered by Didier Pillet and Francisco Falcon, in 2006, near to the town of Pintópolis, with characteristics similar to those of S.stellatus and S.similis. Everything indicates that it will be necessary to undertake much identifying work with all these populations, in order to achieve a more precise taxonomic analysis of this group.

S. aff.stellatus Photo: Didier Pillet.

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S.trilineatus, Costa and Brasil 1994.

Photo: R. Suzart.

CLASSIFICATION: Trois nouveaux poissons annuels du genre Cynolebias (Cyprinodontiformes, Rivulidae) du basin du rio São Francisco, Brésil. Revue Française d´Aquariologie 21 (1-2): 7-8, figure. ETYMOLOGY: From the Latin trilineatus three lines, in reference to the pattern in the males. TYPE LOCALITY: County of Brasilândia de Minas, state of Minas Gerais. SIZE: Males 65mm, females 55mm. BACKGROUND: Simpsonichthys trilineatus was classified in 1994, based on fishes collected in june of the same year. Specimens of S.alternatus were also found together with

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S.trilineatus, in temporary water pools between João Pinheiro and Brasilândia de Minas, Minas Gerais State. Phylogenetically, it is closely related to S.auratus, as they both present the yellowish coloring on the forward portion of the body and a dark ventro-lateral patch in the males. S.auratus have a larger number of rays on the pelvic fin and denotes the presence of transversal stripes on the central part of the body, besides the absence of horizontal lines on the males bodies. CAPTIVE BREEDING: Follow the same characteristics as for S.auratus. HABITAT AND DISTRIBUTION: Besides the typical locality in the Paracatu river flood-plain in the county of Brasilândia de Minas, another population was discovered by André de Lucca, in Paredão de Minas, with specimens that presented a larger amount of bluish reflexes.

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S.virgulatus, Costa and Brasil 2006.

Photo: Francisco Falcon.

CLASSIFICATION: Three new species of the seasonal killifish genus Simpsonichthys, subgenus Hypsolebias (Teleostei: Cyprinodontiformes: Rivulidae) from the Paracatu river drainage, São Francisco river basin, Brazil. Zootaxa 1244: 4155 (2006). ETYMOLOGY: A reference to the coloring in the males, from the Latin virgulatus - with different-colored bands. TYPE LOCALITY: Unaí county, the state of Minas Gerais, in the “Ribeirão entre Rios” floodplain, in the Paracatu river basin. SIZE: Males 50mm, females 33mm. BACKGROUND: Only just discovered and described, this species is closely related to S.trilineatus and S.auratus. Only after a recent collection in 2008, was this fish introduced into the aquarian sphere.

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CAPTIVE BREEDING: Until this date, no information on breeding is available, but the pattern should be similar to that of S.auratus and S.trilineatus. Water conditions of the pool follow the same patterns as those of most South American annual fishes, with a very low electric conductibility and an acid pH of 5,5. A curious fact which inspired attention was the water temperature, for, even though the day was cloudy and with occasional rain, this was high, 29°C. HABITAT AND DISTRIBUTION: Only the typical locality is known, the “Ribeirão entre Rios” flood-plain, in the Paracatu river basin. The pool was extremely large by annual pool standards in the region, measuring about 200m long and 40m wide. The only species encountered was S.virgulatus, together with a small number of aquatic insects. The maximum depth in the center of the pool was 75cm. There was abundant plant-life, with grass and some Echinodorus sp.

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Ophtalmolebias, Costa 2006. A subgenus formed by 5 known species: S.bokermanni, S.constanciae, S.suzarti, S.perpendicularis and S.rosaceus. Distribution is located in river basins of the Brazilian Atlantic coast, although it is probable there are more species of this group, mainly in the state of Bahia. Their original habitat was situated within the Atlantic Rain Forest, where both soil and excess of decomposing organic matter determine a very low pH for dark-colored water. These fishes are pacific in behavior, with little or almost no territorial conduct having been registered. Cladogram, with the phylogenetic relationships of the subgenus Ophtalmolebias (Costa, 2006).

S.constaciae

S.suzarti S.bokermanni

S.perpendicularis S.rosaceus

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S.bokermanni, Carvalho and Cruz 1987.

Photo: M. Chauche.

CLASSIFICATION: A new Cynolebias from southeastern Bahia (Pisces, Cyprinodontidae, Rivulinae). Arq. Univ. Fed. Rural Rio de Janeiro 8:11-15. ETYMOLOGY: In honror of its discoverer, the naturalist Werner Bokermann. TYPE LOCALITY: Ilhéus county, in the state of Bahia. SIZE: Males reach approximately 60mm and females 55mm. BACKGROUND: Discovered in 1971 by the naturalist Werner Bokermann, during regional research on amphibians, in the CEPLAC (Comissão Executiva do Plano da Lavoura Cacaueira) Forest Reserve. Descriptive work was only published in 1987. In 1989, on returning from Sergipe to São Paulo, I stopped over for a day

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in the town of Ilhéus, where I rented a car and went looking for S.bokermanni. Near to the CEPLAC, I encountered several pools containing a large number of the species. There were also fishes in pools at the side of a small earth-road. I took them with me to São Paulo and distributed them among aquarist friends. CAPTIVE BREEDING: This has proven to be an easy fish to keep in captivity, with a relatively short turf-drying period of between 45 to 70 days. At birth fry are big, and from the start feed on salt-water Artemia naupilii. Sexing is also quick, and in approximately two months it is possible to distinguish males from females. It is highly recommended for beginners. HABITAT AND DISTRIBUTION: Besides the areas within and at the side of the CEPLAC Forest Reserve, both of which are very close one to another and probably communicate at the time of heavy floods, another population was discovered by Marcos de Almeida. This new population stands apart by presenting black spots on the dorsal fin. The pool follows the same pattern as localities in the Atlantic Rain Forest, where the forest floor becomes flooded and water acquires a dark color, with the persistent entanglement of branches and plants. Carbonated and total hardness of the water is zero, with a slightly acid pH, 6,38, and a temperature close to 20ºC. S.bokermanni is a passive easy-to-keep fish, and is not very demanding regarding the quality of the water, adapting well to clear water and artificial goodquality food.

S.bokermanni female Photo: Fabrício Rezende.

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S.constanciae, Myers 1942.

Photo: M. Chauche.

CLASSIFICATION: Studies on South-American Freshwater fishes I. Stanford Ichthyological Bulletin 2 (4): 105-106. ETYMOLOGY: In honor of the wife of Colonel T. White, the collector of the species. TYPE LOCALITY: Cabo Frio county, the state of Rio de Janeiro. SIZE: Males 58mm, females 48mm. BACKGROUND: This fish was discovered in 1941 by Colonel Thomas White, and described by Myers in the following year, to be newly found only in November of 1973 by the herpetologist Carlos Cruz, who described it once again based on specimens collected in Rio das Ostras county, publishing the results in 1976. Nowadays, this species is widely distributed among aquarists. This is really important, because in nature there is wide-spread devastation of biotypes in its native area, due to large-scale real-estate speculation. Consequently, it is seriously

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threatened by extinction. Until 1993, S.constanciae was included in Appendix II of the Washington International Convention on Threatened Fauna and Flora Species (CITES). After the Osaka, Japan Conference (1993), S.constanciae was removed from the list, although its situation in nature is still very vulnerable. It is commonly encountered among Rivulidae breeders all over the world. This fact could be of help in recuperating natural environments through the supply of fish for re-introduction. CAPTIVE BREEDING: It is one of the easiest of the Simpsonichthys to breed in captivity. For this reason it is very highly recommended for beginners. The couple buries completely into the substratum for spawning eggs, which are ready to hatch after 60 days of drying. The ease in raising these fishes derives from their breeding characteristics. They are fishes that deposit a large amount of eggs, and these, prior to hatching, can bide their time until the breeder decides to place them in water. They are pacific fishes and fights seldom occur among males. They adapt easily to the most varied water conditions. Eventually, embryos can form and eggs hatch without the need of drying. This was something that came to my notice in 2002. At birth, fry already start feeding on naupilii, and in approximately 2 months they already begin breeding activities. HABITAT AND DISTRIBUTION: Distribution is restricted to an area between the towns of Cabo Frio and Rio das Ostras, on the north coast of the state of Rio de Janeiro, a region undergoing intense real-estate valorization due to its nearness to several beautiful beaches. In a locality in Rio das Ostras, very near to the beach and around 200 meters from the sea, they were able to be found together with N. whitei and Lept. cruzi. In the year 2000, this locality was a flooded area of approximately 500m2. Nevertheless, nowadays this has been reduced to an area of less than 50m2, within a residential lot. This was the only known place where Lept.cruzi was present, although now it is no longer so. Pools with S.constanciae are, on an average, 50cm deep, containing very dark-colored and acid water, with a pH of approximately 6.0.

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S.perpendicularis, Costa, Nielsen and de Lucca 2001.

Photo: R. Suzart.

CLASSIFICATION: Four new annual rivulids of the genus Simpsonichthys (Cyprinodontiformes) from the basins of the São Francisco and Pardo Brasil rivers. Aquarium 26:2431. ETYMOLOGY: Referring to the color pattern of the male’s body consisting of light brown vertical stripes, found only in this species amongst all those of the subfamily Cynolebiatinae. TYPE LOCALITY: The Jequitinhonha river basin, Jordânia, in the state of Bahia. SIZE: Males up to 45mm and females 36mm. BACKGROUND: Discovered by André de Lucca, Danilo Martins and Vladmir Favalli, in an incredible trip which resulted in encountering two new species in a region where

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it was unthinkable to find new species of Simpsonichthys. This result corroborates the theory that there is one or more of this species for each river basin in the south of Bahia. CAPTIVE BREEDING: This fish is easy to keep in captivity, with a relatively short turf-drying period of between 50 to 70 days. Fry are born big and from the first days on feed on salt-artemia naupilii. Sexing is also quick, for in approximately 2 months, it is already possible to distinguish males from females. It is highly recommended for beginners. HABITAT AND DISTRIBUTION: Only the typical locality where it was discovered is known, all fishes distributed among fanciers having derived from the initial collection. The pool occupied an area that was formerly Atlantic Rain Forest, since deforested, and is now covered by grass for cattle-pasture.

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S.rosaceus, Costa, Nielsen and de Lucca 2001.

Photo: M. Chauche.

CLASSIFICATION: Four new annual rivulids of the genus Simpsonichthys (Cyprinodontiformes) from the São Francisco River and Pardo river basins, Brazil. Aquarium 26:2431. ETYMOLOGY: A reference to the predominating color in the males. TYPE LOCALITY: A temporary pool in the Pardo river basin, in the state of Bahia, Potiguara county. SIZE: Males 30mm and females 24mm. BACKGROUND: This species was discovered by André de Lucca, Danilo Martins and Vladmir Favalli in 2000, on the same trip when S.perpendicularis was also found. It was distributed among aquarists in São Paulo, and rapidly became wide-

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spread. Nevertheless, due to its modest color-pattern when compared to other Simpsonichthys species, it did not raise much interest among aquarists, there being few who breed this species in captivity nowadays. CAPTIVE BREEDING: Its breeding in captivity is not difficult, although not so easy as S.perpendicularis or S.bokermanni. Fry are smaller at birth, and it is recommended that, on the first two days, to feed them on infusoria or paramecium. HABITAT AND DISTRIBUTION: Only the typical lcoality is known, a degraded spot of the Atlantic Rain Forest, in a little surveyed region of the south of Bahia State.

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S.suzarti, Costa 2004.

Photo: R. Suzart.

CLASSIFICATION: Simpsonichthys suzarti sp. n. (Teleostei: Cyprinodontiformes:Rivulidae): a new annual fish from the Rio Pardo flood-plains of northeastern Brazil. Zootaxa 468: 17 (2004) ETYMOLOGY: In honror of Rogério Suzart. TYPE LOCALITY: Rio Pardo flood-plain in the county of Canavieiras, in the state of Bahia. SIZE: Male 60mm, female 50mm. BACKGROUND: (Rogério Suzart) This species has already been encountered abroad as “Simp. south Bahia” since the end of the 90’s, through the commercial exportation of ornamental fish. Even though already known by many killiophyles outside Brazil, mainly in

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Europe and the U.S.A., it was only described for the first time in March, 2004 by Professor Wilson Costa, since there was no prior information as to localization of the animal’s biotype, this information being of extreme importance for undertaking descriptive work. After several work trips to South Bahia between 2001 and 2002, whereupon I always made use of the little free time to look for Rivulus, it was only at the end of 2002, after much talk and research together with people living in the region, that I had the good luck to find, in the Rio Pardo basin and in the town of Canavieiras, to the south of Ilhéus, a fish with a color-pattern and shape similar to that of Simp. bokermanni, although presenting a more colored vertical barring and very much more accentuated reflexes on the fins. CAPTIVE BREEDING: (Rogério Suzart) Just like most annual Rivulus, S.suzarti displays agitated territorial behavior. Nevertheless, fights, which only occur between males of breeding age, generally do not provoke injuries greater than slightly frayed fins. Reproduction occurs with the males constantly courting females, by displaying their colors with open and extended fins, until they manage to attract her attention, whereupon she accompanies him to the substratum in which they bury themselves and deposit one egg at a time. This process is repeated during most of the day, the reason why it is convenient to use a proportion of at least 2 females for each male in the reproduction recipient, which will thus attribute a resting time for females, so that they can take turns in spawning. This besides placing some plants or form of refuge from breeding, for the males, on being rejected by the females can eventually become aggressive. The dispause of this species, under a temperature varying from 23 to 30ºC, is of approximately 60 days. Nevertheless, as is well known, for killis yearly rules normally do not dovetail, whereby, for reference the period of diapause in S.suzarti is very much like that of fishes such as S.bokermanni, S.myersi and S.perpendicularis, which are much more common “hobby” fishes. As to substratum humidity during the “dry” phase of the diapause, data regarding the above mentioned species can also be used as reference.

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HABITAT AND DISTRIBUTION: (Rogério Suzart) Seasonal pools, from 2 to 20m2 each, located in shady areas in the Atlantic Rain Forest, in Canavieiras county in the south-coastal portion of Bahia State. In the natural state, S.suzarti inhabits extremely acid and reddish-colored pools of water, the pH varying between around 4,0 and 6,5 as a result of several factors such as rain, the different seasons of the year, etc. It so happens that at certain times of the year, more leaves and fruit fall into the river, thus provoking alterations in its parameters. Curiosity: (Rogério Suzart) At present there is discussion on the existence of one more species of Simpsonichthys which are known abroad under the name of Simp.south Bahia, thus making it possible that there are other species of Simpsonichthys circulating within the international hobby (killiphile), and which are, as yet, unknown by science, as was the case during many years with S.suzarti. Thus it is convenient that there is no crossbreeding among Simp.south Bahia of different origins, since these might be in fact different species.

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Spectrolebias, Costa and Nielsen 1997. This subgenus is composed of 5 species, all inhabiting water basins to the south of the Amazonas, Tocantins, Araguaia and Madeira rivers, except for S.chacoensis which is to be found in the Chaco Paraguaio, which belongs to the Paraguai river basin. Until 2006, the subgenus Spectrolebias was considered to be a genus composed of the species S.semiocellatus and S.filamentosus. S.filamentosus has never been introduced as a hobby fish. Phylogenetic Relationship of the subgenus Spectrolebias (Costa, 2006):

S.reticulatus S.costai

S.chacoensis

S.filamentosus S.semiocellatus

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S.chacoensis, Amato 1986.

Photo: M. Chauche.

CLASSIFICATION: Six new species of the genus Cynolebias Steindachner, 1876, from Uruguay and Paraguay (Cyprinodontiformes, Rivulidae). Comunicaciones Zoológicas Del Museo de Historia Natural de Montevvideo 11(162): 10-11, plates, figures. ETYMOLOGY: A fish originating from the Chaco, the name of a region in northeastern Paraguay. TYPE LOCALITY: Nueva Asuncion, Paraguay. SIZE: Males 30mm, females 26mm. BACKGROUND: In 1982, this species was discovered by an expedition from the Biological Station, Doñana, Spain, and classified by Luis H. Amato in 1986. At the time of the classification, the genus Simpsonichthys was considered invalid. Consequently, the species was classified as Cynolebias even though Amato

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had already verified that it belonged to the S.antenoi group. CAPTIVE BREEDING: As incubation of the eggs takes a long time, this possibly extending up to 6 months, it is recommended that, after placing the turf in water for the first time, dry it again for a fortnight and then place it once more into water. HABITAT AND DISTRIBUTION: Besides the typical locality, the species is found in 4 other places, all within the Paraguayan Chaco. Furthermore, it is probable that distribution extends up to the Argentinean and Bolivian Chacos, as well. The most northerly location is around 100km from the most southerly, which shows it to be a species with wide distribution.

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S.costai, Lazara 1991.

Photo: M. Chauche.

CLASSIFICATION: Cynolebias lacortei, Cynolebias costai and Cynolebias aruana Three new species of cloud fish from Brazil (Teleostei, Cyprinodontiformes, Rivulidae). J. Amer. Killifish Assoc. 23:139-152 ETYMOLOGY: In honror of the discoverer of the species, Luís Costa. TYPE LOCALITY: Temporary pools near to the town of Aruanã, state of Goiás, in the Araguaia river basin. SIZE: A small fish that reaches a maximum size of 25mm. BACKGROUND: Discovered in 1982, by Luís Costa, a fisherman of ornamental varieties from Aruanã, together with other annual fishes, such as Maratecoara lacortei and Plesiolebias aruana. This species was only classified nine years later by Kenneth Lazzara, in an

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edition of the Journal of the AKA (American Killifish Association). Its discovery, together with that of the other sympatric species, created great enthusiasm among aquarists during the 80’s, due to its being a very beautiful fish, much desired by killifish fanciers. Sometimes during the 80’s, they were to be found in fish-fancier shops in São Paulo, but they always arrived in a very weakened condition and quickly died, this leading many dealers to consider this group of fishes unsuitable for aquariums. CAPTIVE BREEDING: It is not recommended for beginners, due to the small size of both eggs and offspring, which demand very small, preferably infusible, feed during the first days of life. The mating occurs naturally, following the same patterns as other Simpsonichthys, with the male and female diving into the substratum. With humidity near to 90% and surrounding temperature around 25ºC, eggs are capable of hatching after 75 to 120 days. A fish that swims slowly and delicately, different from other fishes of the same genus, this species is one of the most fragile and sensitive to shocks, such as abrupt variations in temperature and pH, although, as is the case of most Simpsonichthys, it is resistant and not very demanding in relation to other water conditions, capable of withstanding high levels of nitrates and ammonia. The ideal pH is between 5,5 and 7,0. Males are little aggressive with fellows of the same sex, especially when compared with other species of the genus, and normally fights occur without injury, only with exhibition on the part of both. Females generally do not present aggressive behavior. When either frightened or stressed, these fishes quickly lose their dark body-color, the metalic-blues of the fins fading, returning to normal as soon as the situation becomes stable.

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Photo: R. Suzart. Couple burrowing prior to spawning.

From a detail in the above photo, an egg which has emerged from the substratum can be seen. This is due to the intense movement made by the couple on burrowing in order to spawn, an occurrence repeated several times during the day. HABITAT AND DISTRIBUTION: On the margins of the Araguaia river basin there is an accompanying plain along almost all its extent, whereby from half of its course up to the estuary of the Tocantins river, the river itself and its tributaries run on a level which allows for the formation of temporary pools close to their margins. On the Araguaia river, there occurs the largest fresh water island in the world, Bananal Island, with extensive flooded areas. The pool itself where S.costai was discovered is more than 10km long. In 1996, when on a trip to the Tocantins river basin, together with André Carletto and André de Lucca, I encountered two populations of S.costai, near to the towns of Brejinho do Nazaré and Alvorada. However, the coloring of the males presented a slightly different pattern to the normal. The blue iridescent spots were concentrated in the head region and not spread throughout the body. When on the same trip, we came across a population of S.costai near to the town of Formoso do Araguaia, already in the Araguaia river basin. The water here was slightly dark with a pH of 5,8 and a temperature at 26ºC. The dense vegetation was formed of aquatic plants and grass. This was a very big pool at the roadside, being more than 2km long and 90cm deep.

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S.filamentosus, Costa, Barrera and Sarmiento 1997.

Draw: Ruud Wildekamp.

CLASSIFICATION: Simpsonichthys filamentosus, une nouvelle espèce des Llanuras Benianas, bassin du Rio Mármore, Bolívia. Revue fr. Aquariol, 24, 3-4, 1997. ETYMOLOGY: From the Latin filamentosus, in reference to the long ray-like filaments on the dorsal and anal fins of the males. TYPE LOCALITY: The department of Santa Cruz, Bolívia. SIZE: Males 34mm, females 28mm. BACKGROUND: If there is a fish that can be identified by its own name, this fish is S.filamentosus. No other species have such long filaments on the anal and dorsal fins as this one does. Discovered in 1997 and classified in the same year this species, thus opening

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the possibility of existing there many species of Simpsonichthys in the water basins of rivers to the south of the Amazon basin, a region as yet little explored and surveyed for members of the group Rivulidae. Since publication of the work on classification, any aquarist who has had the opportunity to see the photos must dream of the day when owning one. Until this date there is no news of this species in captivity. CAPTIVE BREEDING: Nothing is known on breeding, for, as mentioned above, it has never been kept in an aquarium. HABITAT AND DISTRIBUTION: Only the typical locality is known, a flooded region in the San Pablo river basin, a tributary of the Mamoré river, in the department of Santa Cruz. The pool is 40cm deep, with clear water and much grass.

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S.reticulatus, Costa and Nielsen 2003.

Photo: M. Chauche.

CLASSIFICATION: Simpsonichthys reticulatus n. sp. (Cyprinodontiformes: Rivulidae): a new annual fish from The Rio Xingu floodplains, Brazilian Amazon. ETYMOLOGY: A reference to the male’s color pattern. TYPE LOCALITY: Flooded areas on the banks of the Xingu River, Altamira county, in the state of Pará. SIZE: Male 21mm, female 18mm. BACKGROUND: There is a community of fishermen in the Altamira region, in the state of Pará, dedicated to commercializing and exporting ornamental fish. The discovery of this species is due to this community, who, from the first, set

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about sending it to Europe together with other species of Pituna and Plesiolebias. Thus, the first to become acquainted with the species were European aquarists. In Europe it was named Simpsonichthys sp. Xingu. In 2003, after spending 4 months looking for information, I managed to make contact with a fisherman from this community, a certain Jackson Diniz, who knew of a place where these annual fishes were to be found. At the right time, when the water began to lower, he sent me some specimens of this species, which served for undertaking classification work. CAPTIVE BREEDING: (Rogério Suzart) The male pursues the female throughout the day, courting her with completely opened fins and displaying his exuberant colors. (figs 1, 2 and 3). With swift movements in front of the female, the male tries to lead her to the substratum, swimming towards this to after return again to a position facing her, as though trying to indicate the spot chosen by him for her to lay her egg. Seduced by the colors and frenetic movements of the male, the female finally accompanies him. The male buries the front portion of his body, vertically pointing with the mouth turned downwards, simultaneously vibrating both body and fins (fig. 3), until the female places herself beside him and in the same position (fig. 5). At this moment, the couple bury themselves totally, with a synchronized movement of the bodies, whereupon the female lays a single egg which is immediately fertilized by the male in the bottom of the substratum. (fig. 5). The burial of the male in the substratum lasts around 10 seconds, after which he emerges (fig. 6). The couple repeats this process several times during the day and while there is still light, only resting when the light fails. DATA ON THE DIAPAUSE AND EGG HANDLING: As this fish was only recently introduced among aquarists, very little information is available related to specific breeding data. Nevertheless, according

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Photos: R. Suzart.

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to the area where it occurs, we can have a vague notion of the time that the eggs should remain ‘dry’ and the moisture necessary for the substratum with eggs during the diapause period. Thus, ‘probably’ the time of diapause of the animal should vary between 2 to 4 months at a temperature between 24 a 29ºC. The moisture of the substratum ‘should’ be high, as is the case for fishes of the genera Pterolebias and Plesiolebias, which occur in those areas nearest to that of S.reticulatus, which is why they were taken as reference. This makes it evident why it is so important, on acquiring any animal, to search for all possible information, such as, behavioral and feeding habits, where it occurs and particular characteristics and necessities, all of which will indicate the best way to keep and/or breed them. HABITAT AND DISTRIBUTION: Only the typical locality is known which is the town of Altamira, in the state of Pará and on the margins of the Xingu river. It lives sympatric with Pituna xinguensis and Plesiolebias altamira, in pools with much aquatic plant-life.

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S.semiocellatus, Costa and Nielsen 1997.

Photos: M. Chauche.

Classification: A new genus and species of annual fish (Cyprinodontiformes, Rivulidae). Ichthyol. Explor. Freshwaters, vol 7, nº 3, pp. 257-265, 17 figs, 1 tab, mach 1997. Etymology: From the Latin semi - half, and ocelatus - with ocellum, referring to the black patch on the anal fin of males.

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Type Locality: Near to Formoso do Araguaia, in the state of Tocantins, the Araguai river basin. Size: Males 35mm, females 28mm. Coloring: The color pattern is unique among species of Rivulidae. The male is transparent, which gave origin to the Latin name “spectrum”, thus allowing one to perceive the swim-bladder and spine. Background: In the holidays of Easter week, in the beginning of april, ‘96, I invited André Carletto and André de Lucca to go collecting in Tocantins. We left São Paulo by plane on Saturday, March 31st, and flew to Brasília. We arrived there at nightfall and rented a small car, heading for the north of the state. On the same day had been there a rebellion in a prison in the state of Goiás, and a number of convicts had managed to escape. Right at the beginning of the road, we ran into a police barrier, where some of the fugitives had been arrested only a few minutes before our passing. We continued on our trip and slept in Anápolis. On the following morning we went ahead until the next town, Alvorada, the first after the border between the states of Goiás and Tocantins. Here we changed direction and headed east, on a precarious earth-road going towards the Tocantins river. Immediately in the first pool we came across, close to the Morro Alegre river, we encountered 3 species of Rivulidae: Maratecoara formosa, Plesiolebias aruana and Simpsonichthys costai. The Simpsonichthys costai called our attention by the distribution pattern of iridescent blue spots, as all were concentrated in the region of the head and not along the body, as is commonly the case in the populations near to the Araguaia river. By the side of the pool there was a Buriti with a couple of very noisy nesting parrots. A little further ahead, we came across a very shallow pool with clear water and a large number of Pituna compacta. As it was getting dark, we decided to return to Alvorada where we stayed the night.

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On the following morning, we continued the trip by the same earth road, heading east towards the Tocantins river. On arriving, we passed through the town of Peixes. Thereabouts, we did not find any promising pool. We went ahead in a northerly direction, passing through the town of Gurupi, and continued to that of Brejinho do Nazará. One year before and in this same spot, Maratecoara formosa and S.multiradiatus had been discovered. After some hours looking, we located a pool in the middle of a corn plantation, where we found specimens of M.formosa, Pituna compacta and Plesiolebias xavantei. In the deepest part of the pool alone, which reached 1,50 meters deep, we encountered three S.multiradiatus, one male and two females. Near to the plantation there was an enormous pool entering into the forest, thereby making it impossible to calculate its size. It was approximately 50cm deep, but very dangerous, for during the dry period, its clayey substratum was extracted to make tiles in a nearby brickyard. So there were many holes throughout the pool, some reaching three meters deep. Nevertheless, there were many annual fish, enormous specimens of Trigonectes strigabundus and the same S.costai found the day before with the same characteristic distribution of iridescent blue spots, besides Plesiolebias xavantei and Maratecoara formosa. It was an incredible place, with much vegetation, many aquatic plants and some small Characids. We continued the trip and stayed overnight in Gurupi. The following day, we went to the town of Formoso do Araguaia. We passed through the town and proceeded to the “Ilha do Bananal”. A few kilometers ahead, just after a large rice plantation in which there was an enormous number and variety of birds, we encountered a pool along the land road. As soon as I began casting the net, I caught a S.semiocellatus. I became half-paralyzed and overjoyed, as it was a very different fish from the other Rivulidae that we already knew. The pool was not very big, and for many kilometers along this same road there were others pools with annual fishes. On this pool itself, we found 7 species of Rivulidae, this being the one with the largest number of species of Rivulidae that I have ever encountered or even heard of. The species found herein were: S.costai, M.lacortei, Ples.lacerdai, Ples.aruana, Pituna compacta, and T.rubromarginatus, besides the new species S.semiocellatus. In some pools it was possible to observe the behavior of T.rubromarginatus. It rapidly rose to the surface, stopping suddenly to open its pelvic fins and afterwards plunge downwards. It repeated this swimming pattern several times, providing a sensational spectacle. It is very interesting to observe the behavior of a Rivulidae

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in its natural environment. We began the trip back and once again passed the night in the town of Alvorada. During the night we were awakened by the sound of shots between the police and escaped prisoners, this happening right in front of our hotel. On the following morning we decided to return to the first pool we had collected at for a last look. While André Carletto and André de Lucca were in the pool, I remained packing the fishes. At this moment, I saw three men come out of the forest and walk towards us. At once I had the notion they were escaped prisoners, as the night before we had heard that the police had not been able to recapture the group that was in the region. At once opened the hood of the car and disconnected the wires of the battery, so as to make belief there was a defect in the car. The men approached and began to ask the reason for our stopping at that place, and when I told them we were waiting for help for the broken car, they began to walk away along the road. At that exact moment, they saw a police car arriving, whereupon they quickly ran into the forest. So, then I saw that we were in a dangerous region, and that it would be safer to leave at once. We packed our bags and fishes and returned to Brasília, where we caught a plane back to São Paulo. Captive breeding: S.semiocellatus has proved to be a difficult fish to breed in captivity. Its eggs are very small and fragile, disappearing into the turf during the time of drying. Besides this, it is not very prolific, as few eggs are laid per couple. Very few aquarists have been able to raise this species in captivity, maybe through not being capable of achieving the exact conditions of water chemical and physical parameters, in order to be successful in its breeding. The aquarist Edson Lopez, regarding his experience in captive-breeding, states: “In order to breed S.semiocellatus, I used an aquarium containing turf approximately 1 cm thick, with a breeding couple or groups of 3 couples and much plant-life. After a month the turf was removed and dried in the shade. In the winter, when environmental temperature is between 19ºC to 24ºC, incubation lasted from 7 to 8 months, whereas in the summer fry hatched in around 4 to 5 months. When the turf is moistened, it can take up to three days for fry to hatch. Apparently older couples lay eggs of a better quality. I have already had fishes more than 1 year old that bred better and lived longer in captivity”.

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Didier Pillet, the renowned French fancier, tells about his success in breeding S.semiocellatus: Approximately 30 fishes were placed in a fifty liter aquarium containing abundant plant-life (moss and microsorium). Aggressiveness was limited to male territorial borders, and only when an intruder invaded the territory of its neighbor. Lighting was intense, but softened by dense plant-life, fishes remaining half-way up the water column. Male courtship-display is used to attract the females, whereat the coloring of the former undergoes an alteration, with the disappearance of transparency. The invitation to submerge is made, but females only lay eggs on the substratum, without burying. In february, 2001, I received two couples of young adults. They were immediately placed into a 25 liter aquarium, with a French 12°TH, pH 7.8 and temperature at 23°C. Aquarium decoration was composed of Java moss and some ferns. After removing some eggs measuring around 0.8 mm in diameter, that had been incubating for up to 12 weeks at 24°C, I noted with satisfaction the birth of 50 fry. They were initially fed on infusoria and a micro-worm for around three days. After this they accepted well salt-water artemia naupilii. Eighteen days later, I transferred half of the fry to a 25 liter tank. From this first generation, I acquired 20 males and 10 females altogether, that bred abundantly. On spawning for the second time, several eggs disappeared into the substratum. The formation of embryos takes from 2 to 3 months, at an average temperature of 24°C. Going over experience with other breeders, it was put forward that the eggs are very sensitive, their fragile chorion bursting when under high pressure or when in water with high conductibility. This problem is avoided when the eggs are kept in water with conductibility below 50µS. A crucial factor for success is to offer fry Paramecium during the first days of life, and not change the water, keeping the fish in old water. Habitat and Distribution: The pool where S.semiocellatus was discovered follows the temporary

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environmental pattern of the Araguaia river basin, with slightly acid water and the absence of dissolved mineral salts, total hardness and carbonated remaining at zero. The color of the water is slightly dark, due to the decomposing vegetationmatter on the bottom that constitutes the pool substratum. Aquatic plants, such as Echinodorus sp. and Ultricularia sp., are abundant.

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Xenurolebias, Costa 2006. A subgenus composed of two species, S.myersi and S.izecksohni. They are able to be found in the northern coastal region of the state of Espírito Santo and the south of the state of Bahia. They are distinguished from the other Rivulus by possessing, filamentous rays on the borders of the anal fin in the female, and a lanceolate and asymmetric tail fin due to the expansion of the ventral part in the males. The color pattern is also unique, in that it consists of a stripe on the hind-portion of the caudal peduncle that extends above the dorsal and ventral margins of the tail fins in the males. (Costa, 2006). Etymology: From the Greek Xenos/strange, oura/fin, lebias/small fish, the latter also a common name used in the composition of the names of Cyprinodontideos.

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S.izecksohni, Cruz 1983.

Draw: Ruud Wildekamp.

CLASSIFICATION: A new species of Cynolebias from the state of Espírito Santos, Brazil. (Pisces, Cyprinodontidae). Pap. Avulsos Zool. 35:73-77. ETYMOLOGY: In honor of the herpetologist Eugenio Izecksohn. TYPE LOCALITY: Linhares county, state of Espírito Santo. SIZE: Males 55mm, females 45mm. BACKGROUND: This species was first collected in 1975 by the author of the description, Carlos Cruz, in the Forest Reserve of the enterprise Capixaba de Pesquisas Agropecuárias. Later in 1980, other specimens were also collected in the Forest Reserve of the Companhia do Vale do Rio Doce, also in Linhares county. Based on specimens from the two sites, Cruz described the species in 1983.

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For a long time, S.izecksohni was considered a synonym of S.myersi, and only in the year 2000 was it re-validated as an independent species. CAPTIVE BREEDING: There is no mention of this species in captivity, although it probably follows the same breeding behavior as S.myersi. HABITAT AND DISTRIBUTION: The only localities known are in the above mentioned forest reserves. This information on the habitat is from the time of collection by Carlos Alberto Gonçalves da Cruz: The first collection site was formed by an extensive swamp, inside a patch of forest belonging to the enterprise “Empresa Capixaba de Pesquisa Agropecuária”. The bottom of the swamp was constituted of a light layer of decomposed organic matter on a sandy substratum. The water was dark-colored and trees on the banks kept the spot in shade. At the time, the greatest depth was 0,50m. At the second collection site, in the “Companhia Vale do Rio Doce” Forest Reserve, we localized several small pools in an open environment, where plant-cover was mainly composed of grass, with small-sized pteridophytes both on the banks and actually in the pool. The substratum was sandy with a thin layer of organic matter. Here also, the water was of a dark color (Costa, 2002).

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S.myersi, Carvalho 1971.

Photo: M. Chauche.

CLASSIFICATION: A new annual fish from the state of Espírito Santo (Pisces, Cyprinodontidae). Rev. Brasil. Biol. 31: 401-404. ETYMOLOGY: In honor of the American ichthyologist George Myers. TYPE LOCALITY: Itaunas county, in the state of Espírito Santo. SIZE: Males 55mm, females 50mm. BACKGROUND: Discovered in 1969 by Antenor de Carvalho, the species was only classified in 1971. In 1984 it was introduced among aquarium fanciers, through a collection undertaken by Júlio Ghisolfi and Carlos Tatsuda, who collected specimens in Conceicão da Barra, around 20km to the south of Itaunas. Later, populations were

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found near to the towns of Caravela and Prado, in Bahia. CAPTIVE BREEDING: This species is easy to breed and is resistant to aquarium sicknesses, thus being recommended for the beginner. Egg drying time can be abbreviated by exposing them to temperatures approaching 30ºC and high humidity. Males are not very aggressive on defending their breeding territories. HABITAT AND DISTRIBUTION: The species is encountered between the towns of Conceição da Barra in the state of Espírito Santo and Prado in Bahia, in pools which, notwithstanding native forest degradation, maintain the yearly cycle, thus making survival of the species possible. In 1998, I discovered a population in a gabbage dump in the town of Prado.

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Nematolebias, Costa 2006. Even though they do not belong to the genus Simpsonichthys, the species of Nematolebias, have for many years been considered as Simpsonichthys. So, for this reason, I have introduced this genus in the book. Nowadays, through deeper phylogenetic analyses, it has been discovered that the Nematolebias are less related with Simpsonichthys than with Cynolebias and Austrolebias. Two species of N.whitei and N.papilliferus are recognized, both occurring on the north coast of the state of Rio de Janeiro. Very popular as hobby items, these very beautiful species already present albino varieties, they being one of the few species of Rivulidae to offer this mutation.

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Nematolebias papilliferus, Costa 2002.

Photo: M. Chauche.

CLASSIFICATION: A seasonal neotropical fish of the genus nematolebias (Cyprinodontiformes: Rivulidae: Cynolebiatinae): a taxonomic revision with the description of a new species. ETYMOLOGY: From the Latin pappilla and ferus, in reference to the hypertrophied contact organs on the pectoral fins of the males. TYPE LOCALITY: Inoã county, state of Rio de Janeiro. SIZE: Males 65mm, females 40mm. BACKGROUND: For many years the populations of N.papilliferus were considered as N.whitei. It was only in may, 2002, that the two species were separated. Many of the aquarium fishes considered as N.whitei are in fact N.papilliferus.

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For this reason, when acquiring a species, it is always advisable to know the population so that when a systematic alteration occurs, the species can be correctly identified. CAPTIVE BREEDING: Breeding habits are the same as N.whitei. HABITAT AND DISTRIBUTION: Some habitats are known near to Inoã and Sampaio Correia on the north coast of the state of Rio de janeiro. In some localities in Inoã, it is to be found sympatric with Lept. fractfaciatus.

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Nematolebias whitei, Myers 1942.

Photo: M. Chauche.

CLASSIFICATION: Studies on South American freshwater fishes I. Stanford Ichthyological Bulletin 2 (4):106-107. ETYMOLOGY: In honor of the discoverer Thomas White. TYPE LOCALITY: Seasonal pools around 10 to 12km to the north of Cabo Frio. SIZE: Males 75mm, females 60mm. BACKGROUND: Discovered by the American air pilot Colonel Thomas White, near to the town of Cabo Frio on the north coast of the state of Rio de Janeiro, during the early 40’s. At the end of the 50’s, some specimens collected in Cabo Frio were sent to Germany by dealers in ornamental fishes from Rio de Janeiro. The aquarist Werner Ladiges described the fishes sent as being a new species, Pterolebias elegans,

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which is a synonym of N.whitei. In 1955, Antenor de Carvalho found the species near to the locality of São Pedro da Aldeia, and published a paper with information on breeding behavior, habitat and the species’egg. During a trip to the region in 2001, we encountered a pool on the top of a hill near to the town of Cabo Frio. The pool, visibly artificial, was being used as a drinking place for horses. During the same trip we came upon two more localities, one in the town of Rio das Ostras and the other in São Pedro da Aldeia. In nature, this species is seriously threatened with extinction, due to increasing real-estate speculation in the region where it occurs. CAPTIVE BREEDING: This fish reproduces very readily in captivity, and is considered by some fanciers as the easiest to breed of the seasonal species. Its breeding is so facile as to constitute one of the few species of Rivulidae to have an albino variety. We must only take heed with the behavior of the males when placed together, as there is always dispute as to which one will be the alpha male, which in turn could lead to fights with grave outcome. Nevertheless, after establishment of the dominant male, the rest become subjugated to this one. Some subdued males reach the point of languishing, to finally die. Thus, it is not advisable to leave more than one male in the same aquarium. On a certain occasion, shifts were tried out among the females. They were allowed to spawn for one week, to then be left alone for one more. On once again being placed together with males, the females began to provoke these by small nudges on their anal fins, as though wishing to stimulate the male to spawn. The eggs hatch around 50-60 days after the substratum dries. Fry are big at birth and from the beginning readily accept artemia naupilii as food. HABITAT AND DITRIBUTION: The pools where N.whitei occurs spread from the county of São Pedro da Aldeia to that of São João da Barra. These pools are around 50cm deep, with a substratum made up of decomposing vegetation, which thus causes the water to be extremely dark. The predominant plant-life consists of grass. In many places, N.whitei lives together with S.constanciae. Generally there are two rainy seasons in the year, one in may and the other in december, although there are reports of collections being carried out throughout

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all the months of the year, which confers great plasticity to the species in relation to spawning, maybe this being one of the reasons for the facility of breeding this species in captivity.

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Conclusion

The aquatic environment constitutes one of those which have been most degraded over the latter 50 years. All or the most part of these environments are threatened to a greater or lesser degree by the constant search for new resources, necessary for sustaining a human population in constant growth. In spite of this sad account, even nowadays, we are able to discover new species of aquatic animals. Nevertheless, the number of species that have been extinguished has grown to a worrying point. Among the 51 known species of Simpsonichthys and the two of Nematolebias, we encounter two species, S.zonatus and S.marginatus, which are already considered as extinct in Nature, and are only to be found in aquariums throughout the world. Certain species, such as, S.santanae, S.boitonei, S.brunoi, S.multiradiatus, S.alternatus, S.fasciatus, S.carlettoi, S.adornatus, S.gibberatus, S.rufus, S.nielseni, S.aratus, S.virgulatus and S.constanciae, are in deadly danger, whereas, S.magnificus, S.picturatus, S.bokermanni and S.perpendicularis are considered vulnerable. In more developed countries such as the U.S.A., Japan and in Europe, there are associations exclusively dedicated to breeding these fishes, and even though their aim is not to preserve the diverse species, these groups end up by doing important work in the conservation of the Simpsonichthys and Nematolebias. A passion for the h obby has been responsible for a great number of discoveries of new species, especially over the latter 20 years, several aquarists going to all extremes to maintain these beautiful fishes. Even though several members of the scientific community regard aquarists with concern, it is only in aquariums that many species encounter the means for salvation from extinction. The importance of our keeping several species in captivity goes far beyond a mere hobby. It could be one of the only alternatives for several species to be able to survive in the near future. Breeding these fishes constitutes one of the most agreeable hobbies, due to their resistance, beauty and possibility of social reciprocity. The Simpsonichthys and the Nematolebias are really jewels, gifts from

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Nature, which we must preserve for future generations to be able to admire. I hope that this book will be of help to science and amateur ornamental fish breeders, in keeping and breeding their fishes in the best possible conditions. Thank you, Dalton Tavares Bressane Nielsen

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References AMORIM, D. de S. Fundamentos de Sistemática Filogenética. Ribeirão Preto: Holos, 2002. BELOTE, D.F. Estudo da Evolução dos padrões de comportamento e reprodutivo de Cynolebiatini (Ciprinodontiformes, Rivulidae) UFRJ, Museu Nacional, 2000. BELOTE, D.F. e COSTA, W.J.E.M. Reproductive behavior patterns in the Neotropical annual fish genus Simpsonichthys Carvalho, 1959 (Cyprinodontiformes, Rivulidae): Description and Phylogenetic implications.Boletim do Museu Nacional 2002, n° 489. BERKENKAMP, H.O. Ein neuer Fa cherfisch aus dem Bundesstaat Minas gerais, Brasilien, Cynolebias hellneri sp.n.das Aquarium 27 (290):8-15, figures, map, 1993. CARVALHO, A.L., Notas para conhecimento da Biologia dos Peixes Anuais. Revista Brasileira de Biologia, Rio de Janeiro: 17 (4): 459-466, 1957. CARVALHO, A.L. Novo gênero e nova espécie de peixe anual de Brasília, com uma nota sobre os peixes anuais da Baixada Fluminense, Brasil (PiscesCiprinodontidae-Fundulinae). Boletim do Museu Nacional, Rio de Janeiro: 201,1-10, 1959. CARVALHO, A.L. Um novo peixe anual do estado do Espírito Santo (Pisces, Cyprinodontidae). Rev. Brasil. Biol. 31: 401-404, 1971. CODEPLAN/GDF. Atlas do Distrito Federal II. Brasília, Governo do Distrito Federal, 383p. 1984. COSTA, W.J.E.M. Descrição e relações filogenéticas de dois gêneros novos e três espécies novas de peixes anuais neotropicais (Cyprinodontiformes, Rivulidae). Rev. Brasil. Biol. 49 (1): 221-230,1989. COSTA, W.J.E.M. e CASTRO D. O peixe do Céu. Ciência Hoje das Crianças. Rio de janeiro (48): 23-25, 1995. COSTA, W.J.E.M. Phylogenetic and Biogeographic Analysis of the Neotropcal Annual Fish genus Simpsonichthys (Cyprinodontiformes: Rivulidae). Jornal of Camparative Biology. 1:129-140, 1996. COSTA, W.J.E.M. Descrição de quatro novas espécies anuais do gênero Simpsonichthys (Cyprinodontiformes: Rivulidae) das bacias do rio São Francisco e Paraná, Nordeste e centro do Brasil. Revista Aquarium 25:8-15, 2000.

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COSTA, W.J.E.M. Peixes Anuais Brasileiros: diversidade e conservação. Curitiba: Ed. da UFPR, 2002. COSTA, W.J.E.M. The Simpsonichthys flavicaudatus species group (Cyprinodontiformes: Rivulidae: Cynolebiatinae): phylogenetic relationships, taxonomicrevision and biogeography. Ichthyol. Explor. Freshwaters, vol 14, nº 1, pp.31-60, 17 figs, 5 tabs. March, 2003. COSTA, W.J.E.M. Descriptive morphology and phylogenetic relationships among species of the Neotropical annual killifish genera Nematolebias and Simpsonichthys (Cyprinodontiformes: Aplocheiloidei: Rivulidae) - Neotropical Ichthyology, 4(1):1-26, 2006. COSTA, W.J.E.M. e BRASIL, G.C. Simpsonichthys radiosus sp. n. (Teleostei: Cyprinodontiformes: Rivulidae): a new annual killifish from the upper rio Tocantins basin, central Brazil. Zootaxa 737: 17, 2004. COSTA, W.J.E.M. e BRASIL, G.C. Three new species of the seasonal killifish genus Simpsonichthys, subgenus Hypsolebias (Teleostei: Cyprinodontiformes: Rivulidae) from the rio Paracatu drainage, rio São Francisco basin, Brazil. Zootaxa 1244: 4155, 2006. COSTA, W.J.E.M e NIELSEN, D.T.B. Simpsonichthys reticulatus n. sp. (Cyprinodontiformes: Rivulidae): a new annual fish from The rio Xingu floodplains, Brazilian Amazon. Aqua Journal of Ichthyology and Aquatic Biology, 8,125-130, 2003. COSTA, W.J.E.M; CYRINO, A.L.F. e NIELSEN, D.T.B. Description d´une nouvelle espèce de Poisson annuel du genre Simpsonichthys (Cyprinodontiformes: Rivulidae) du basin du rio São Francisco, Brésil. Rev. Franç. Aquariol, 23:17/-20, 1996. COSTA, W.J.E.M., MOREIRA, C.R. e LIMA, F.C.T. Simpsonichthys Cholopteryxn. sp. (Cyprinodontiformes: Rivulidae: Cynolebiatinae): a new dwarf annual fish from the upper rio Araguaia basin, central Brazil, 2003. CRUZ, C.A.G. Uma nova espécie de Cynolebias do estado do Espírito Santos, Brasil. (Pisces, Cyprinodontidae). Pap.Avulsos Zool. 35:73-77, 1983. EITEN, G. Delimitation of cerrado concept. Vegetatio, Bangor, 36 (3): 169-178, 1978. MAGURRAN, A.E. e GARCIA, C.M. Sex differences in behaviour as an indirect consequence of mating system. Journal of Fish Biology. London, 57: 839-857, 2000.

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NICO, L.G. e TAPHORN, D.C. Limnology of Orinoco basin - Annual killifish pools. Journal of American Killifish Association. New York, 19 (2): 59-72, 1984. PARENTI, L.R. A phylogenetic and biogeographic analysis of ciprinodontiform fishes (Teleostei, Atherinomorpha). Bul.Am.Mus.Nat.Hist. 168:335-557, 1981. SCHÄFER, A. Fundamentos de Ecologia e Biogeografia das Águas Continentais. Porto Alegre: Editora da Universidade, 532p, 1985. SHIBATTA, O.A. e BENNEMANN, S.T. Plasticidade alimentar em Rivulus pictus Costa (Osteichthyes, Cyprinodontiformes, Rivulidae) de uma pequena lagoa em Brasília, Distrito Federal, Brasil. Revista Brasileira de Zoologia. Curitiba, 20 (4): 615-618, 2003. SHIBATTA, O.A. e GARAVELLO, J.C. Descrição de uma nova espécie do gênero Cynolebias Steindachner do Brasil Central (Pisces: Cyprinodontiformes). Comunicações do Museu de Ciências da PUCRS, Série Zoologia. Porto Alegre, 5 (11): 179-195, 1992. SHIBATTA, O.A. Reprodução do pirá-brasília, Simpsonichthys boitonei Carvalho (Cyprinodontiformes, Rivulidae) e caracterização de seu habitat na Reserva Ecológica do Instituto Brasileiro de Geografia e Estatística, Brasília, Distrito Federal, Brasil. Revista Brasileira de Zoologia, novembro de 2005. SHIBATTA, O.A. Comportamento social do pira-brasília, Simpsonichthys boitonei Carvalho (Cyprinodontiformes, Rivulidae). Revista brasileira de Zoologia 23 (2): 375-380 junho de 2006. VAZZOLER, A.E.A.M., 1996. Biologia da Reprodução de peixes teleósteos: Teoria e Prática. CNPq e Nupelia (UEM). WOURMS, J.P. The developmental Biology of annual fishes III. Pre-embryonic and embryonic diapause variable duration in the eggs of annual fishes. Journal of Experimental Zoology. Hoboken, 182: 389-414, 1972. WOURMS, J.P. Annual fish oogenesis 1. Differentiation of the mature oocyte and formation of the primary envelope. Develop. Biol. 50:338-354, 1976.