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

Abstract

Tetragonopoterus aeneus Hensel (1870) is removed from synonymy with Astyanax fasciatus (Cuvier, 1819), revalidated and redescribed as A. henseli to avoid homonymy. Astyanax henseli differs from A. fasciatus stricto sensu and other Astyanax species by the presence of two to four maxillary teeth, two vertically-elongated humeral spots, dentary tooth cusps positioned close to one another, and the slender form of the dentary teeth.Tetragonopterus aeneus Hensel (1870) é retirada da sinonimia de Astyanax fasciatus (Cuvier, 1819), revalidada e redescrita como A. henseli para evitar homonímia. Astyanax henseli diferencia-se de A. fasciatus stricto sensu e das demais espécies de Astyanax pela presença de dois a quatro dentes no maxilar, duas manchas humerais verticalmente alongadas, cúspides dos dentes do dentário situadas próximas entre si, e dentes do dentário relativamente estreitos.

Cytogenetic and morphological diversity in populations of Astyanax fasciatus (Teleostei, Characidae) from Brazilian northeastern river basins

“…The level of divergence between them suggests the occurrence of a species complex, widespread throughout distinct river basins. A similar situation has been described in several neotropical fishes, particularly within Astyanax (Moreira-Filho and Bertollo, 1991;Melo and Buckup, 2006), showing that more detailed taxonomical reviews should be carried out in order to provide a reliable scenario about the diversity of the Brazilian ichthyofauna.…”

“…The predominant diploid numbers of this species are 2n = 46 and 2n = 48, but they can range from 45 to 48 and present quite differentiated chromosome formulae (Morelli et al, 1983;Centofante et al, 2003;Pazza et al, 2006, among others). These results, supported by morphological studies (Melo and Buckup, 2006), suggest that the species currently referred as Astyanax fasciatus should be divided into other nominal evolutionary units.…”

“…So far, the genus comprises 92 valid species and recent descriptions are about to increase this number (e.g. Bertaco and Lucena, 2006;Melo and Buckup, 2006).…”

A new species of Astyanax (Ostariophysi: Characiformes: Characidae) from the upper rio Iguaçu basin, southern Brazil

“…Members of this clade were characterized by the presence of hooks on fin rays, absence of supraorbital, presence of two unbranched plus eight branched dorsal fin rays, and presence of four teeth in the inner premaxillary row. This clade was latter supported by molecular and morphological phylogenetic studies (Calcagnoto et al, according to Melo & Buckup (2006); A. burgerai (according to the original description in Zanata & Camelier, 2009); A. turmalinensis (according to Triques & Queiroz, 2010); and A.bifasciatus Garavello & Sampaio, 2010 (according to the original description). Among Bryconamericus species this variation was reported for B. pyahu Azpelicueta, Casciotta & Almirón (according to original description in Azpelicueta et al, 2003); B. orinocensis and B. singularis Román-Valencia (according to Román-Valencia et al, 2008), B. cf.…”

A new species of Astyanax Baird & Girard (Ostariophysi: Characidae) from the rio Taquari-Antas basin, southern Brazil

“…Furthermore, A.bagual can be distinguished from A. laticeps by the presence of two vertically elongate humeral spots (vs. one horizontally elongate spot), and by the number of branched anal-fin rays (24-28 vs. 15-23), and from A. henseli by the shape of the first humeral spot (see diagnosis), by the caudal peduncle spot (spot wide and expanded dorsally and ventrally vs. spot restricted to center of caudal peduncle; see Melo & Buckup, 2006), and an absence of space between the dentary teeth, which are slender vs. presence of space between dentary teeth. In the remaining species, the maxillary is either toothless or usually with a single tooth, rarely two teeth.…”