aqua, International Journal of Ichthyology

Cynolebias akroa, a new of annual (: ) from the rio Preto, São Francisco basin, northeastern Brazil

Dalton Tavares Bressane Nielsen1, Mayler Martins2, Luciano Medeiros de Araujo3, Fabio Origuela de Lira4 and Amer Faour5

1) Laboratório de Zoologia, departamento de Biologia, Universidade de Taubaté, Av. Tiradentes180, CEP: 12030-180, Taubaté, SP, Brazil. E-mail: [email protected] 2)Instituto Federal Minas Gerais- Campus Bambuí- Fazenda Varginha-Estrada Bambuí-Medeiros Km 5, CEP: 38900-000, MG, Brazil. E-mail: [email protected] 3) Fundação Zoobotânica de Belo Horizonte – Aquário da Bacia do São Francisco Avenida Otacílio Negrão de Lima, 8000; Belo Horizonte, MG Brasil. E-mail: [email protected] 4) Meandros Consultoria Ambiental Ltda., Rua Maria Cândida Cerqueira, 75, Santa Amélia, Belo Horizonte/MG, Brasil. Email: [email protected] 5) C/ Las Fuentes 4 bajo C - 37439 - San Cristóbal de la Cuesta - Salamanca. E-mail: [email protected]

Received: 20 October 2017 – Accepted: 25 November 2017

Keywords als mit den anderen Cynolebias-Arten vom mittleren Rio- Caatinga domain, , Cynolebias parnaibensis, São-Francisco-Becken. Cynolebias akroa sp. n. unterschei- introduced species. det sich von den anderen Arten der Gattung durch das Farbmuster der Männchen, die Stellung der Rückenflosse Abstract relativ zu der Afterflosse, die Zahl der Bauchflossenstrah- A new species of Cynolebias is described from temporary len, die Form der Urogenitalpapille und das Muster der pools from the Rio Preto drainage, São Francisco basin, Neuromasten im Kopfbereich. Bahia, Brazil, within the Caatinga domain. The type-local- ity is an altered aquatic environment, with the presence of Resumo exotic fish species and in contact with a permanent water- Uma nova espécie de Cynolebias é descrita a de uma poça course. Cynolebias akroa sp. n., along with Hypsolebias temporária da drenagem do Rio Preto, bacia do São Fran- faouri, that inhabits the same annual pool, are in great dan- cisco, Bahia Brasil, no bioma da Caatinga, em um ambien- ger of extinction. Cynolebias akroa sp. n., appears to be te aquático alterado, com introdução de espécies exóticas e more closely related to Cynolebias parnaibensis, with which em contato com um curso de água permanente. Cynolebias it shares several features, than to the remaining species of akroa sp. n., juntamente com Hypsolebias faouri, que habita Cynolebias from the middle Rio São Francisco basin. a mesma poça anual, estão em grande perigo de extinção. Cynolebias akroa sp. n. differs from other species of Cynolebias akroa sp. n., parece estar mais relacionada com Cynolebias by the male color pattern, relative position of Cynolebias parnaibensis, por uma série de características co- dorsal fin to the anal fin, pelvic-fin rays counts, shape of muns, do que com as demais espécies de Cynolebias do mé- the urogenital papilla, and cephalic neuro mast pattern. dio rio São Francisco. Cynolebias akroa sp. n. difere de ou- tras espécies do gênero Cynolebias pelo padrão de colorido Zusammenfassung dos machos, posição relativa da nadadeira dorsal em rela- Beschrieben wird eine neue Cynolebias-Art aus temporä- ção a nadadeira anal, número de raios na nadadeira pélvica, ren Tümpeln im Einzugsgebiet des Rio Preto, São-Francis- forma da papila urogenital e padrão dos neuromastos cefá- co-Becken, Bahia, Brasilien, im Bereich der Caatinga. Die licos. Typus-Lokalität ist eine veränderte aquatische Umwelt, wo exotische Fischarten vorkommen und Kontakt zu einem Résumé dauerhaften Wasserlauf besteht. Cynolebias akroa sp. n., Une nouvelle espèce de Cynolebias est décrit à partir de ebenso Hypsolebias faouri, der denselben zeitweiligen Tüm- mares temporaires du Rio Preto, drainage du bassin du São pel bewohnt, sind stark von Ausrottung bedroht. Cynole- Francisco, Bahia, Brésil, dans le domaine de caatinga. La bias akroa sp. n. ist offenbar näher mit Cynolebias parnai- localité type est une altération de l'environnement aquati- bensis verwandt – mehrere Merkmale stimmen überein – que, avec la présence d'espèces de poissons exotiques et en

113 aqua vol. 23 no. 4 - 15 March 2018 Cynolebias akroa, a new species of annual fish (Cyprinodontiformes: Rivulidae) from the rio Preto, São Francisco basin, northeastern Brazil contact avec un cours d'eau permanent. Cynolebias akroa Fifteen Cynolebias species occurs at the middle São n. sp., avec Hypsolebias faouri, qui habite le même taux an- Francisco basin, while Cynolebias microphthalmus nuel d'extérieure, sont en grand danger d'extinction. Cyno- Costa & Brasil (2001) occurs in the Rio Jaguaribe lebias akroa n. sp., semble être plus étroitement liée à Cy- basin, Cynolebias parnaibensis Costa et al. (2010) nolebias parnaibensis, avec laquelle elle partage plusieurs ca- ractéristiques, que pour les autres espèces de Cynolebias du occurs in the Rio Parnaíba basin, Cynolebias itapi- milieu du bassin du Rio São Francisco. Cynolebias akroa n. curuensis Costa (2001) occurs in the Rio Itapicuru sp. diffère des autres espèces de Cynolebias par l'homme, basin, Cynolebias paraguassuensis Costa et al. position relative de nageoire dorsale à la nageoire anale, (2007), occurs in the Rio Paraguaçu basin, rayons pelviens-chefs, la forme de la papille urogénitale, Cynolebias vazabarriensis Costa (2001) occurs in neuro-mast céphalique et motif. the Rio Vaza-Barris basin, and Cynolebias griseus Costa et al. (1990) occurs in the Rio Tocantins Sommario basin. Una nuova specie di Cynolebias è descritta da pozze tem- All species of Cynolebias have an annual re- poranee del sotto bacino del Rio Preto, bacino idrografico del Rio São Francisco, Bahia, Brasile, all'interno del domi- production cycle, with an elaborated reproductive nio Caatinga. La località tipo è un ambiente acquatico al- behavior (Belote & Costa 2003), including the terato, con la presenza di specie ittiche esotiche e in con- production of sounds by males (Costa 2010). In tatto con un corso d'acqua permanente. Cynolebias akroa contrast to most other Rivulidae, the genus sp. n., insieme a Hypsolebias faouri, che abita nella stessa Cynolebias contains medium to large sized species, pozza annuale, sono in grande pericolo di estinzione. Cy- which can surpass 80 mm SL; the largest known nolebias akroa sp. n., sembra essere più strettamente impa- species, C. altus, presents 133.3 mm SL (Costa rentato con Cynolebias parnaibensis, con cui condivide di- 2001). Despite their size, they are not used for hu- verse caratteristiche, rispetto alle restanti specie di Cynole- bias dal bacino centrale del Rio São Francisco. Cynolebias man comsuption because they are said to have a akroa sp. n. differisce dalle altre specie di Cynolebias per la very bad taste. In some areas species of the genus colorazione del maschio, per la posizione della pinna dor- are called “peixe-sabão” (“soap fish”), but more of- sale rispetto alla pinna anale, per il numero dei raggi della ten they are popularly known as “peixe-das-nu- pinna pelvica, per la forma della papilla urogenitale e per il vens” (“cloud s fish”). pattern neurommastico cefalico. In most of the known localities of species of Cynolebias, they are sympatric with species of the INTRODUCTION annual fish genus Hypsolebias. It has been suggested The first annual fish species described from in that species of Cynolebias prey on species of the South America was Cynolebias porosus Steindachner, genus Hypsolebias (Wildekamp 1995). 1876. The stated type-locality was “Pernambuco” The new species described herein was found in a (now Recife, the capital city of the state of Pernam- tributary of the left bank of the rio São Francisco, buco in northeastern Brazil), but as discussed by situated farther away from its main channel than Costa (2001), it is difficult to ascertain the precise any other species of the genus. The aim of the pre- origin of this species, which was never collected sent contribution is to describe formally this unde- again in nature. scribed species. For a long time, the genus Cynolebias was a catch- all taxon, harboring species which are currently as- MATERIALS AND METHODS signed to several other genera of Rivulidae. In fact, a Measurements were taken point-to-point under a great proportion of the South American annual fish stereomicroscope with a digital caliper to the near- species that were described before the 1980 s were est 0.01 mm, on the left side of the specimens, then assigned to the genus Cynolebias. With the in- whenever possible, following Costa (1995, 2007). crease of studies on the family, along with fieldwork Measurements are expressed as percentages of stan- and discovery of new species, new genera were cre- dard length (SL), except subunits of the head, ated for species previously assigned to Cynolebias, which are recorded as percentages of head length such as Austrolebias, Nematolebias, , (HL). Hypsolebias, , , Plesi- In the description, counts of vertebrae and pleural olebias, Cynopoecilus, , Terranatos, and ribs were taken from one male and one female Maratecoara. cleared and stained (c&s) paratypes, which were The majority (15 out of 21) of the species of prepared according to Taylor & Van Dyke (1985). Cynolebias were described during the last 15 years. Terminology for frontal squamation follows aqua vol. 23 no. 4 - 15 marzo 2018 114 Dalton Tavares Bressane Nielsen, Mayler Martins, Luciano Medeiros de Araujo, Fabio Origuela and Amer Faour Hoedeman (1958) and Costa (2006). For vertebral Cynolebias akroa, n. sp. counts, the caudal compound centrum was count- (Figs 1-2; Table I) ed as a single element. Osteological features includ- ed in the description are those considered phyloge- Holotype: ZUEC 14768, male, 75.0 mm SL: Bra- netically informative by recent studies on zil, Bahia, Prazeres, temporary pool at road BA- Cynolebias (Costa 2001, 2014, 2017; Costa et al. 225, rio Preto basin (Rio São Francisco basin), 2010). Institutional abbreviations follow Sabaj 11°23’24.8”S 44°54’11.2”W, altitude 522 m, 25 (2016), with addition of UNITAU (Universidade January 2014; Mayler Martins, Fabio Origuela de de Taubaté). Lira & Luciano Medeiros de Araujo. Paratypes: ZUEC 14769, 5 males 35.1-62.5 mm

Fig.1. Cynolebias akroa, ZUEC 14768, male, holotype, 75.0 mm SL: Brazil, Bahia, Santa Rita de Cássia. Photo by D. Nielsen.

Fig. 2. Cynolebias akroa, ZUEC 14769, female, paratype, 59.2 mm SL: Brazil, Bahia, Santa Rita de Cássia. Photo by D. Nielsen.

115 aqua vol. 23 no. 4 - 15 March 2018 Cynolebias akroa, a new species of annual fish (Cyprinodontiformes: Rivulidae) from the rio Preto, São Francisco basin, northeastern Brazil

Table I. Morphometric and meristic data for the holotype cephalus, C. microphthalmus, C. oticus, C. parietalis, (H) and paratypes of Cynolebias akroa. C. parnaibensis, C. paraguassuensis, C. rectiventer, C. vazabarriensis, C. gorutuba, and 5th-7th in C. ob- H Paratypes scurus, and C. roseus), number of anterior rostral Male Males n=5 Females n=6 cephalic neuromasts 6 (vs. 2-3 in C. obscurus, C. Standard length (mm) 75.0 35.1-62.5 44.5-61.3 ochraceus, C. oticus, C. paraguassuensis, C. parietalis, Percents of standard length C. parnaibensis, C. elegans, and C. gorutuba, and 3- Body depth 28.8 26.4-29.8 29.0-30.9 4 in C. rectiventer), and urogenital papilla in males Caudal peduncle depth 15.1 11.1-14.4 13.6-15.6 cylindrical and elongated (vs. cylindrical and Pre-dorsal length 62.5 61.3-68.4 64.0-70.0 short). Pre-pelvic length 52.0 47.5-52.9 50.3-56.6 Females of Cynolebias akroa differs from females Length of dorsal-fin base 24.0 22.1-25.6 19.7-23.8 of the remaining species of Cynolebias by overall color pattern light gray, with 10-12 pale, large Length of anal-fin base 27.2 27.4-30.6 17.4-28.2 brown bars, and black spot in the center of body Caudal-fin length 26.5 27.3-30.7 20.0-28.2 sometimes absent (vs. overall color pattern light Pectoral-fin length 25.0 21.4-27.0 19.3-23.6 gray without bars and black spot always present in Pelvic-fin length 7.5 4.2-7.3 5.7-7.4 C. microphthalmus, C. porosus, C. vazabarriensis, C. Head length 35.5 32.5-33.8 31.9-34.6 perforatus, C. altus, C. leptocephalus, C. attenuatus, Percents of head length C. gibbus, and C. rectiventer, light gray body with Head depth 82.6 76.8-80.5 70.0-82.4 faint gray vertical bars, and one or two dark gray to Head width 64.5 60.3-63.4 27.5-33.6 black spots in C. itapicuruensis, C. paraguassuensis, Snout length 13,9 13.8-14.4 11.1-11.6 and C. parnaibensis, pale brownish grey, lacking Lower jaw length 25.2 24.2-27.3 22.1-24.9 spot on anteriormedial portion of flank, and 1-3 Eye diameter 24.8 24.1-28.3 20.1-23.3 dark brown blotches on humeral region in C. ob- scurus, light gray body with faint gray vertical bars, SL, 6 females 44.5-61.3 mm SL, 2 c&s, 54.7-77.9 one or two dark gray to black blotches in C. roseus), mm SL, same date as holotype. lower caudal fin length 20.0-28.2 % SL (vs. 34.1- Diagnosis: Cynolebias akroa differs from the re- 38.0 % SL in C. ochraceus or 28.7-32.4 % SL in C. maining species of Cynolebias by presenting overall parietalis). color pattern metallic golden-green, with 11-13 Additionally, Cynolebias akro can be distinguished large, light black bars (vs. 16-18 narrow, dark from the remaining species of the Cynolebias, ex- brown bars in C. obscurus, 17-19 yellow brown cept C. gorutuba, by a higher number of post-otic bars separated by narrow dark golden interspace in cephalic neuromasts (11, vs. 5-8 in C. obscurus, C. C. oticus, faint gray vertical bars (sometimes ab- ochraceus, C. oticus, C. paraguassuensis, C. parietalis, sent) in C. microphthalmus, C. vazabarriensis, C. C. parnaibensis, and C. rectiventer). itapicuruensis, C. perforatus, C. porosus, C. altus, C. Description: Morphometric data are presented in leptocephalus, C. attenuatus, C. gibbus, narrow pale Table I. Largest male specimen examined 75.0 mm golden bar in C. parnaibensis), color pattern of cau- SL, largest female 77.9 mm SL. Dorsal and ventral dal fin hyaline, without dots (vs. light gray in C. profiles convex between snout and anterior part of gorutuba, dark brown in C. paraguassuensis, dark caudal peduncle, nearly straight on caudal peduncle. grey with white dots in C. microphthalmus, C. poro- Body moderately deep, slightly compressed, greatest sus, and C. vazabarriensis, grey with bluish white body depth at level of vertical just anterior to pelvic- dots in C. itapicuruensis, C. rectiventer, C. gilbertoi, fin base. Snout very short, blunt. Dorsal and anal C. obscurus, and C. parietalis, yellowish gray with fins slightly pointed in males, without filaments, white dots in C. perforatus, C. altus, C. lepto- rounded in females. Pectoral-fin long, rounded, cephalus, C. attenuatus, C. gibbus, and C. par- reaching vertical between base of 2nd and 3rd anal- naibensis, dark ochre-yellow with bluish white dots fin rays in males, and between pelvic-fin base and in C. roseus, greenish yellow in C. oticus), seven anus in females. Tip of pelvic fin reaching between pelvic fin rays (vs. 5 in C. griseus and 6 in the re- base of 1st and 3rd anal-fin rays in males, 1st anal-fin maining species), dorsal-fin origin through base of rays in females. Pelvic-fin bases medially separated 8th or 9th anal-fin ray (vs. 3rd-6th in C. altus, C. at- by interspace. tenuatus, C. gibbus, C. itapicuruensis, C. lepto- Dorsal-fin origin through base of 8th or 9th anal- aqua vol. 23 no. 4 - 15 marzo 2018 116 Dalton Tavares Bressane Nielsen, Mayler Martins, Luciano Medeiros de Araujo, Fabio Origuela and Amer Faour fin ray in males, and above base of 4th or 5th anal- Second pharyngobranchial teeth absent. Gill-rak- fin ray in females; dorsal-fin origin between neural ers on first branchial arch 10, 8 in the second arch. spines of vertebrae 15-17 in both sexes. Anal-fin ori- Vomerine teeth absent. Urogenital papilla cylindri- gin between pleural ribs of vertebrae 13 in males, cal, large and elongated. Total vertebrae 32-33. and pleural ribs of vertebrae 12 in females. Dorsal- Coloration: Males. Side of body metallic fin rays 17 in males, 15-16 in females; anal-fin rays golden-green, with 11-13 large light black bars, 19 in males, 18-20 in females; caudal-fin rays 28-30; fading ventrally before reaching the belly and the pectoral-fin rays 13-14; pelvic-fin rays 7. anal-fin base. Opercular region metallic golden- Frontal scales irregularly arranged; 28 small green. Venter whitish. Head metallic golden, with supraorbital scales. Longitudinal series of scales 37- black lines along laterosensory series of neuromasts 39; transverse series of scales 16-18; scale rows around orbit and on postorbital region. Iris white around caudal peduncle 22. No contact organ on with black vertical bar through eye. Dorsal-fin hya- flank. Minute papillate contact organs on inner line with gray pigmentation on interradial mem- surface pectoral fin-rays in males. No contact or- branes of fin basis, and thin brown lines on inter- gans on pelvic and unpaired fins. radial membranes at distal portion of fin. Caudal- Cephalic neuromasts: supraorbital 29-39, parietal fin hyaline. Anal-fin hyaline with brown pigmenta- 4, anterior rostral 6, posterior rostral 5, infraorbital tion in the last rays. Dorsal and pelvis fins hyaline. 4+29-30, preorbital 3, otic 9, post-otic 11, Females. Sides of body light gray, with 10-12 supratemporal 5, median opercular 3, ventral oper- pale, large brown bars; single rounded black spot in cular 3-5, preopercular + mandibular 47-57, lateral the center of body, sometimes absent. Venter mandibular 8-9, paramandibular 1. whitish. Head sides yellowish gray, pale golden on One neuromast on each scale of lateral line. Two opercular region; small dark reddish brown spots neuromasts on caudal-fin base. along laterosensory series of neuromasts around or-

Fig. 3. Map from northeastern Brazil (inset) showing known localities for Cynolebias from the rio São Francisco basin.

117 aqua vol. 23 no. 4 - 15 March 2018 Cynolebias akroa, a new species of annual fish (Cyprinodontiformes: Rivulidae) from the rio Preto, São Francisco basin, northeastern Brazil bit and on postorbital region. Iris orangish yellow solved calcium (Ca) 60 mg/l, dissolved copper (Cu) with dark reddish brown vertical bar through cen- 0 mg/l. The temperature on the water surface was ter of eye. Dorsal and anal fins hyaline, with small approximately 28°C and, in the deepest portion and blue metallic spots between last rays. Caudal-fin at the margins, approximately 25°C. The region’s hyaline with small metallic blue spots. Paired fins annual average temperature is 28°C, with maxi- hyaline. mum of 34°C and minimum of 20°C. The rainy Distribution (Fig. 3): Known only from the type season ranges from December to March. The period locality, a temporary pool beside the highway BA- of collection coincided with a “Veranico” (Indian 225, at Santa Rita de Cássia, rio Preto, rio São Summer), a phenomenon which consists of a dry Francisco basin, Bahia state, Brazil. period with high temperatures within the rainy sea- Habitat (Fig. 4): The type-locality is a typical an- sons (Nielsen 2008). Together with Cynolebias akroa nual pool of the Caatinga, located about 96 km were also found Hypsolebias faouri, Astronotus ocella- north of Barreiras. The substrate is composed of clay tus and Oreochromis niloticus (Figs 5-6). and sand, with a slightly dark water. There is a dense The pool is close to a road near a small village. A cover of aquatic vegetation, mostly composed by family living in this village introduced Oreochromis Echinodorus sp. and Nymphaea sp. The average niloticus and Astronotus ocellatus on the pool, as a depth of the pool is 100 cm, with deepest portions means of having an alternative source of protein. about 130 cm, pH 6.5 and a low electric conductiv- At one end the pool was dug so the water would re- ity (146µs). Other physico-chemical parameters main throughout the year, so part of the pool does were: total hardness (GH) 2°dGH, carbonate hard- not dry, which explains the survival of the intro- ness (KH) 4°dKH, dissolved iron (Fe) 1.0 mg/l, dis- duced species.

Fig. 4. Type locality of Cynolebias akroa, Brazil, Bahia, temporary pool at road BA-225. Photo by M. Martins. aqua vol. 23 no. 4 - 15 marzo 2018 118 Dalton Tavares Bressane Nielsen, Mayler Martins, Luciano Medeiros de Araujo, Fabio Origuela and Amer Faour

Etymology: In honor Akroá ethnic, an ethnic The area of occurrence of the new species is locat- group belonging to Macro-Jê linguistic trunk, that ed approximately 175 km in a straight line from lived in the region until the century XIX, when the Rio São Francisco, but the real distance from they were decimated. its main channel, considering the actual rivers courses is approximately 570 km. The middle Rio DISCUSSION São Francisco basin lies within the Caatinga do- Cynolebias akroa is easily distinguished from its main, an area with a relatively high rate of biodi- congeners by the presence of light dark vertical bars versity, with high level of speciation for rivulids, in the flank. This color pattern is unique within but with a consequently limited distribution of the genus Cynolebias, other species of the genus each species. The accelerated pace of environmen- may present vertical bars, but never as wide and tal degradation, due to the disorderly occupation conspicuous as the ones present in the new species. of the area by human activities, poses a great risk of extinction for rivulid species occurring at the Caatinga domain (Costa 2017). Cynolebias species are commonly found in annual pools sintopically with two other annual fish species of the genus Hypsolebias, typically one species be- longing to the Hypsolebias magnificus species group and other species belonging to the Hypsolebias flav- icaudatus species group. Rarely, Cynolebias species are found alone in an annual pool. Cynolebias akroa was found syntopically with Hypsolebias faouri. Hypsolebias faouri is closely related to H. igneus (Britzke et al. 2016), a species that occurs in annual pools at the banks of the Rio São Francisco, near the Rio Preto mouth with the Rio São Francisco. Cynolebias akroa could be putatively closely related to Cynolebias roseus, considering the geographic Fig. 5. Astronotus ocellatus, a specimen of an exotic invasive proximity between the two species and a similar dis- species, collected at the type-locality of Cynolebia akroa. Photo by M. Martins. tribution of H. faouri and H. igneus. However, Cynolebias akroa appears to be more closely related to C. parnaibensis, since both species share the fol- lowing characteristics: color pattern with vertical bars, absence of contact organs in the body sides of males vomerine teeth absent, second pharyngob- ranchial teeth absent, a similar count of dorsal-fin rays (17 in males vs. 16-18 in other species), a com- mon count of dorsal-fin rays in females (15-16), a common count of anal-fin rays (19 in males and 18-20 in females), a common count of caudal-fin rays (28-30), a common count of pectoral-fin rays (13-14), frontal scales irregularly arranged, dorsal fin origin vertebrae 15-17, and the presence of minute papillate contact organs on inner surface pectoral fin-rays in males. Interestingly, the clade formed by H. faouri and H. igneus is closely related to the clade formed by H. coamazonicus and H. martinsi (Britzke et al. 2016), which is similar to the putative biogeographic relation between C. akroa Fig. 6. Oreochromis niloticus, a specimen of an exotic inva- from the middle Rio São Francisco basin with C. sive species, collected at the type-locality of Cynolebia parnaibensis from the Rio Parnaíba basin. akroa. Photo by M. Martins. In spite of the modification of its habitat, with

119 aqua vol. 23 no. 4 - 15 March 2018 Cynolebias akroa, a new species of annual fish (Cyprinodontiformes: Rivulidae) from the rio Preto, São Francisco basin, northeastern Brazil the establishment of a connection to a permanent COSTA, W. J. E. M. 2009. Morphology of the teleost pha- water body and with the invasion of exotic fish that ryngeal jaw apparatus in the Neotropical annual killifish potentially can act as predators as Astronotus ocella- genus Cynolebias (Cyp rinodontiformes: Aplocheiloidei: tus and Oreochromis niloticus, Cynolebias akroa still Rivulidae). Cybium 33: 145-150. COSTA, W. J. E. M. 2010. Historical biogeography of survives in its habitat. Cynolebias akroa is not the cynolebiasine annual killifishes inferred from dispersal-vic- most abundant species of annual fish at its habitat, ariance analysis. Journal of Biogeography 37: 1995-2004. being outnumbered by Hypsolebias faouri, with a COSTA, W. J. E. M. 2011. Parallel evolution in population ratio of 5: 1 in relation to H. faouri, ichthyophagous annual killifishes of South America and which may indicate that C. akroa preys on H. Africa. Cybium 35: 39-46. faouri, as reported for other syntopic associations COSTA, W. J. E. M. 2014. Six new species of seasonal kil- among annual rivulids (e.g., Wildekamp 1995). lifishes of the genus Cynolebias from the São Francisco The morphological characteristics of the teeth, typ- river basin, Brazilian Caatinga, with notes of C. porosus (Cyprinodontiformes: Rivulidae). Ichthyological Explo- ical of piscivorous , common to all Cynolebias ration of Freshwaters 25: 79-96. species and shared with other annual fishes from COSTA, W. J. E. M. 2017. Description of two endangered both South America and Africa, as Austrolebias new seasonal killifish species of the genus Cynolebias from elongatus and Nothobranchius ocellatus, which are the São Francisco River basin, Brazilian Caatinga reported to prey on smaller sympatric congeners (Cyprinodontiformes, Aplocheilidae). Zoosystematics and (Costa 2006, 2009, 2011, 2017), also points to Evolution 93 (2), 333-341. this possible relation of predator-prey between COSTA, W. J. E. M. & BRASIL, G. C. 2001. The neotropi- Cynolebias akroa and Hypsolebias faouri. cal annual fish genus Cynolebias (Cyprinodontiformes: Rivulidae): phylogenetic relationships, taxonomic revi- sion and biogeography. Ichthyological Exploration of Fresh- ACKNOWLEDGEMENTS waters 12: 333-383. Thanks are due to Itamar Alves Martins from COSTA, W. J. E. M., LACERDA, M.T.C & BRASIL, G. C. Universidade de Taubaté (UNITAU) for laboratory 1990. Description de deux nouvelles espèces du genre support and Flávio C. T. Lima (ZUEC), who read Cynolebias du bassin du Rio Tocantins (Cyprinodontifor- the manuscript and offered useful suggestions. mes, Rivulidae). Revue Française d’Aquariologie et Herpe- tologie 17: 9-14. REFERENCES COSTA, W. J. E. M, SUZART, R. & NIELSEN, D. T. B. 2007. Cynolebias paraguassuensis n. sp. (Teleostei: Cyprinodon- BELOTE, D. F. & COSTA, W. J. E. M. 2003. Reproductive behavior of the Brazilian annual fish Cynolebias albipunc- tiformes: Rivulidae), a new sazonal killifish from Brazi- tatus Costa & Brasil, 1991 (Teleostei, Cyprinodontif- lian Caatinga, Paraguaçu River basin. aqua, International ormes, Rivulidae): a new report of sound pro duction in Journal of Ichthyology 12 (3): 129-133. fishes. Arquivos do Museu Nacional 61: 241-244. COSTA, W. J. E. M., RAMOS, T. P. A., ALEXANDRE, L. C., RAMOS, R. T. C. 2010. Cy nolebias parnaibensis, a new BRITZKE, R., NIELSEN, D. T. B. & OLIVEIRA, C. 2016. Description of two new species of annual fishes of the seasonal killifish from the Caatinga, Parnaíba River basin, Hypsolebias antenori species group (Cyprinodontiformes: northeastern Brazil, with notes on sound pro ducing Rivulidae), from Northeast Brazil. Zootaxa 4114 (2): courtship behavior (Cyprinodontiformes: Rivulidae). 123-138. Neo tropical Ichthyology 8: 283-288. HOEDEMAN, J. J. 1958. The frontal scalation pattern in COSTA, W. J. E. M. 1995. Pearl killifishes: The Cynolebiati- nae. Systematics and Biogeography of a Neotropical annual some groups of tooth carps. Bulletin of Aquatic Biology 1: fish subfamily (Cyprinodontiformes: Rivulidae). TFH Pub- 23-28. lications, Neptune City, 128pp. NIELSEN, D. T. B. 2008. Simpsonichthys e Nematolebias. Cabral Editora e Livraria Universitária, Taubaté, 235pp. COSTA, W. J. E. M. 2001. The neotropical annual fish genus Cynolebias (Cyprinodontiformes: Rivulidae): phylogenetic SABAJ, M. H. 2016. 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A world of killies: atlas of the (Teleostei: Cyprinodontiformes: Aplocheiloidei: Rivuli- oviparous cyprinodontiform fishes of the world, volume 2. dae). Zootaxa 1669: 1-134. American Killifish Association, Mishawaka, 384 pp. aqua vol. 23 no. 4 - 15 marzo 2018 120