A new species of the catfish genus Centromochlus (Siluriformes: Auchenipteridae: Centromochlinae) from the upper rio Paraná basin, Brazil

Abstract

Centromochlus comprises twelve species, distributed in the main inland watersheds of South America, including the Orinoco, Essequibo, coastal rivers of Suriname, Amazon, upper Paraná and São Francisco basins. The new species is described from the upper rio Paraná based on material collected in 1965 during the construction of the UHE Ilha Solteira, São Paulo, Brazil. The new species is easily distinguished from all congeners due to absence of adipose fin, a condition otherwise restricted to Gelanoglanis nanonocticolus, among centromochlin catfishes. The new species comprises small catfishes (adults ranging from 35 to 39 mm SL), in which modified anal fin of males is devoid of denticulations or spines, and most posterior rays reduced in length. In addition, Tatia simplex Mees is transferred to Centromochlus and its generic reassignment discussed.