Distinguished from all congeners by the combination of the following characters: caudal fin- base with a large, elongated blotch (formed by the fusion of the large caudal spot at the fleshy end of the caudal base and the last vertical bar on the flank) that extends about 1/3 of the distance from the caudal-fin origin beyond the last scale on the caudal base to the margin of the caudal fork; anal-fin origin opposing the 2nd-4th branched dorsal-fin rays; eight scale rows above the lateral line; 36 or more precaudal lateral-line scales; dorsal fin with dark pigment concentrated mainly along the margins of the rays; small dentary tubercles; and, if present, a short, small pair of rostral barbels (Ref. 93076).