A single, cone-shaped terminal bulb 0.9-1.5% SL except in the smallest specimen. Barbel relatively short 25-52% SL except in specimens smaller than 7 cm. A single, simple or bifurcate, short terminal filament 5.1-1.6% SL, decreasing relatively with growth. Proximal end of bulb almost flat, with a solid black cap. Axis of stem moderately to lightly pigmented. No spot usually at the base of both. External chevron-shaped or roundish striated areas unpigmented. Middorsal paired spots between occiput and dorsal-fin origin 8 (rarely 9) (Ref. 11333).