Astyanaxelachylepis, a new characid fish from the rio Tocantins drainage, Brazil (Teleostei: Characidae)

Abstract

A new characid species, Astyanax elachylepis, is described from the rio Tocantins drainage. The new species is distinguished from its congeners by possessing 48-53 perforated scales along the lateral line, a large caudal-peduncle spot, the presence of bony hooks on dorsal, anal, pelvic, and pectoral fins of males, one or two vertically-elongated humeral spots, one maxillary tooth, and 22-27 branched anal-fin rays.<br>Uma nova espécie de caracídeo, Astyanax elachylepis, é descrita da drenagem do rio Tocantins. A nova espécie distingue-se de suas congêneres pela presença de 48-53 escamas perfuradas na linha lateral, uma grande mancha sobre o pedúnculo caudal, uma ou duas manchas umerais verticalmente alongadas, um dente no maxilar e 22-27 raios ramificados na nadadeira anal

Astyanax bockmanni Vari and Castro, 2007: an ambiguous karyotype in the Astyanax genus

“…Over the past few years, some new species have been identified, most of them inhabiting small rivers and/or streams, such as: A. cremnobates and A. brachypterygium (Bertaco and Malabarba 2001); A. biotae (Castro and Vari 2004); A. dnophos (Lima and Zuanon 2004); A. totae (Haluch and Abilhoa 2005); A. elachylepis (Bertaco and Lucinda 2005); A. microschemos and A. pelecus (Bertaco and Lucena 2006); A. henseli (Melo and Buckup 2006), and A. bockmanni (Vari and Castro 2007).…”

Astyanax henseli, a new name for Tetragonopterus aeneus Hensel, 1870 from southern Brazil (Teleostei: Characiformes)

“…The characid genus Astyanax Baird & Girard, 1854, includes 92 valid and more than one hundred nominal species ranging from Texas to northeastern Argentina (Azpelicueta et al, 2002;Azpelicueta et al, 2003;Casciotta et al, 2003;Lima et al, 2003:106;Lima & Jahnsen, 2004;Bertaco & Lucinda, 2005;Haluch & Abilhoa, 2005). Eigenmann (1921Eigenmann ( , 1927 was the only author who revised the genus Astyanax.…”

Development of secondary sexual characters and their relationship to ontogeny and seasonal reproductive period in Hyphessobrycon igneus (Ostariophysi: Characiformes)

“…Additional male behaviours and morphological characters, such as courtship displays and fin colour and shape, also appear to play a role in mate choice in many fishes (Forsgren et al ., ), with fin variation being commonly observed in various fish groups (Py Daniel & Cox‐Fernandes, ). The differences in male and female anal‐fin shape observed herein is often used as a character in the study of Characidae systematics (Miquelarena & Aquino, ; Canan & Gurgel, ; Miquelarena & Aquino, ; Bertaco & Lucinda, ; Carvalho, ; Carvalho & Bertaco, ; Matheus, ; Bertaco et al, ; Carvalho et al, ; Lucena & Malabarba, ; Carvalho, ; Jerep & Malabarba, ). Nevertheless, there can be intrageneric variation in this pattern; for example, anal‐fin shape is similar in males and females of H. togoi (Oyakawa et al, ) and Hyphessobrycon nicolasi Miquelarena & López, (Miquelarena & López, ).…”