Ituglanis cahyensis, a new catfish from Bahia, Brazil (Siluriformes: Trichomycteridae)

Abstract

A new trichomycterid catfish of the genus Ituglanis is described from the rio Palmares, a tributary of the rio Cahy in southeast Bahia State, Brazil. Ituglanis cahyensis is distinguished from all other congeners through a combination of characters, as the supraorbital laterosensory canal branch with pores s3 and s6 present, the low count of branched pectoral fin rays, and low number of paired ribs. It is further distinguished in proportional measurements, such as elongate nasal, maxillary, and rictal barbels, and small eye diameter.É descrito um novo trichomycterídeo do gênero Ituglanis, capturado no rio Palmares, um tributário do rio Cahy, na costa sudeste do estado da Bahia, Brasil. Ituglanis cahyensis distingue-se das demais espécies congêneres por uma combinação de caracteres, como o canal laterosensorial supraorbital com os poros s3 e s6 presentes, um pequeno número de raios ramificados nas nadadeiras peitorais, e um pequeno número de costelas. Distingue-se ainda quanto a proporções morfométricas, como os barbilhões nasal, maxilar e rictal alongados, e o pequeno diâmetro ocular.

Description of a new species of Ituglanis (Siluriformes: Trichomycteridae) from Serra dos Carajás, rio Tocantins basin

“…Costa & Bockmann (1993) proposed the genus Ituglanis as a natural group and showed evidence that it is related to the more derived trichomycterids than to species allocated in the genus Trichomycterus. Recent contributions (Fernández & Bichuette, 2002;Wosiacki, 2002;de Pinna & Keith, 2003;Bichuette & Trajano, 2004, 2008Datovo & Landim, 2005;Sarmento-Soares et al, 2006;Campos-Paiva & Costa, 2007) significantly increased the taxonomic and systematic knowledge of the group, corroborating the initial hypothesis that the genus is monophyletic.…”

“…More recent studies (Bichuette & Trajano, 2008;Datovo & Landim, 2005;Sarmento-Soares et al, 2006;de CamposPaiva & Costa, 2007) indicate that the fontanel reduced to a small circular orifice on the supraoccipital is a derived character, exclusive to the group, and not shared by any other species or group of Trichomycteridae. A vaguely similar condition is observed in species of Aspidoras (Callichthyidae), where the foramen of the supraoccipital is reduced.…”

Ituglanis agreste, a new catfish from the rio de Contas basin, northeastern Brazil (Siluriformes: Trichomycteridae)

“…The color pattern of Ituglanis agreste also differs clearly from I. cahyensis that presents longitudinal rows of coalescing blotches (Sarmento-Soares et al, 2006). They also differs by several features, as the higher number of pectoral fin-rays (i,6 vs. i,4), higher number of opercular (17 vs. 9-12) and interopercle (26-30 vs. 16) odontodes, fewer vertebrae (36 vs. 38 or more), higher number of branchiostegal rays (7 vs. 4-6), higher number of ribs (5-6 vs. 4), 13 caudal-fin rays (vs. 10-11), 10-11 anal-fin rays (vs. 7-8) et al, 2006).…”

“…Currently comprised of twenty nominal valid species (Sarmento-Soares et al, 2006;Campos-Paiva & Costa, 2007;Bichuette & Trajano, 2008;Wosiacki et al, 2012), and therefore the second most speciose trichomycterid genus, Ituglanis has a wide distribution in the cisandine Neotropical region, from the Guianas to Uruguay (de Pinna & Keith, 2003), including five troglobitic species found in Central Brazil (Bichuette & Trajano, 2008) and miniaturized forms as I. macunaima from Araguaia Basin (Datovo & Landim, 2005). However, only recently two species of coastal basins of northeastern Brazil were described: I. cahyensis SarmentoSoares, Martins-Pinheiro, Aranda & Chamon and I. paraguassuensis Campos-Paiva & Costa, respectively, from the rio Cahy and rio Paraguaçu coastal basins, in Bahia state (Sarmento-Soares et al, 2006, Campos-Paiva & Costa, 2007.…”

“…However, only recently two species of coastal basins of northeastern Brazil were described: I. cahyensis SarmentoSoares, Martins-Pinheiro, Aranda & Chamon and I. paraguassuensis Campos-Paiva & Costa, respectively, from the rio Cahy and rio Paraguaçu coastal basins, in Bahia state (Sarmento-Soares et al, 2006, Campos-Paiva & Costa, 2007.…”