A New Genus and Species of Hypoptopomatine Catfish (Siluriformes: Loricariidae) from the Upper Rio São Francisco Basin, Brazil
Plesioptopoma curvidens is a new genus and species of hypoptopomatine loricariid from the upper Rio Paraopeba, a tributary to the Rio São Francisco in southeastern Brazil. Plesioptopoma is attributed to the hypoptopomatines based on five shared synapomorphies, and differs from all remaining members of the subfamily by having the premaxilla and dentary tooth series strongly curved mesially, in such a way that the mesial portion of the tooth series in both sides are turned and run parallel to each other, the caudal peduncle distinctly quadrangular in cross-section, and the anterior margin of the snout devoid of dermal plates.
Plesioptopoma curvidens, MCP 46286, holotype, 82.8 mm SL, male, Brazil, Minas Gerais, Cristiano Otoni, Rio Paraopeba, upper Rio São Francisco drainage, at old bridge ca. 100 m W of highway BR-040, 20°49′11″S, 043°48′47″W. White arrow points to exposed area of coracoid.
Pelvic fin of Plesioptopoma curvidens, MCP 46268, 82.8 mm SL, ventral view. Unbranched pelvic-fin ray with odontodes bent and turned mesially. Scale = 5 mm.
Premaxillary tooth series of Plesioptopoma curvidens, MCP 36861. Scale = 1 mm.
Anterior head of Plesioptopoma curvidens, MCP 36861, 38.0 mm SL, lateral view. Scale = 5 mm.
Type locality of Plesioptopoma curvidens in the upper Rio Paraopeba, Rio São Francisco basin, central Brazil.
Pelvic girdle of Plesioptopoma curvidens, MNRJ 21426, dorsal view. B, basipterygium; DP, dorsal process. Scale = 2 mm.
Contributor Notes
Associate Editor: S. A. Schaefer.