Diagnosis: last simple ray partly ossified at base (no strong spine) and distinctly longer than head; lower reduced, substituted by horny sheath; 9-12 (usually 10) dorsal fin branched rays; scale formula 3.5-4.5/23-29/3.5-4.5; 2 scales between lateral line and pelvic-fin base; 12 scales around caudal peduncle (Ref. 2940, 81282).
Description: mouth inferior and broad; barbels very short, especially the anterior part; posterior barbels only 7-15% of head length; scales with striae converging posteriorly; dorsal fin long, with last simple ray ossified at base and as long as head in juveniles, but distinctly longer in adults; D:IV,9-12; A:III,5; P:I,14-16; V:I,8 (Ref. 2940, 81282).
Coloration: uniformly greyish black to greenish, lighter on belly; fins usually dark grey; young individuals with marbling on sides (Ref. 2940, 81282).