Trichomycterus zonatus

materials_examined

FMNH 58572 (1 ex. R-ray) Paratype; FMNH 58573 (X-ray) Holotype; FMNH 58574 (2 ex. 1 X-ray) Paratypes; MZUSP 67913 (6 ex. C & S);

New species of the catfish genus Trichomycterus (Siluriformes, Trichomycteridae) from the headwaters of the rio São Francisco basin, Brazil.

materials_examined

Description of type specimens. Paratype FMNH 58572 not conspecific with remainder of type series, see Discussion, and its discrepant characters indicated in relevant parts of description that follows. Morphometric data for holotype and paratypes in Table 2. See figures 5 and 6 for general external aspect. Body cross-section oval, increasingly compressed posteriorly mainly along caudal peduncle. Body elongate with dorsal and ventral profiles slightly convex on trunk and then nearly straight to caudal peduncle. Body depth approximately even along length of body, slightly decreasing posterior to dorsal-fin origin. Head depressed, as long as wide, trapezoidal in dorsal view. Width of head increasing slightly from snout to end of opercle. Levator mandibulae well-developed, more markedly so in holotype than in paratypes. Mouth subterminal. Upper lip convex, covered with numerous small and short papillae internally and externally. Premaxillary teeth arranged in three well-defined but irregular rows. Dentary teeth arranged in three irregular rows with inner one extending posteriorly to coronoid process. Lower lip well developed, convex and covered with small and short papillae internal and

The type specimens of Trichomycterus alternatus (Eigenmann, 1917) and Trichomycterus zonatus (Eigenmann, 1918), with elements for future revisionary work (Teleostei: Siluriformes: Trichomycteridae)