Diagnosis: lateral line complete (Ref. 80290, 81279) or incomplete (Ref. 2880, 81279). 9-30 pored scales on lateral line (Ref. 81279). 4.5 scales above lateral line; 13-17 anal fin branched rays (Ref. 80290, 81279). 24-30 (Ref. 81279) or 24-27 (Ref. 80290) scales in longitudinal series. 13-17 (Ref. 2880, 81279) or 14-17 (Ref. 80290) gill rakers on lower limb of first gill arch.

Description: big eyes (Ref. 2880). Body slender; body depth 24-29% and head length 24-27% of SL; mouth terminal, lower jaw prominent, its depth about 2x that of upper jaw; premaxilla with 2 teeth in outer row each bearing 3-5 cusps, 4 teeth in inner row each bearing 6 cusps; dentary with 4 teeth in outer row each bearing 3-5 cusps, inner dentary teeth absent; lateral line complete, 23-27 tubes, ultimate canal-bearing scale not terminal, separated from caudal fin rays by 1-2 non canal-bearing scales (Ref. 80290). Anal fin with 3 unbranched and 13-17 branched rays (Ref. 80290, 81279). Very pronounced sexual dimorphism affecting anal-fin shape in adult males (Ref. 2880, 81279).

Coloration: silvery body with brilliant, glossy lateral band along sides, which becomes black after preservation in formalin (Ref. 2880, 81279). Band extends from posterior opercular margin through caudal fin base to margin of median rays; posterior flank immediately above anal fin base with horizontal band reaching to vertical through anus and extending caudad to proximal portion of median anal fin rays (Ref. 80290). Melanophores at anal-fin base much more distinct than visible in Micralestes species (Ref. 2880, 81279). Dorsal midline with dark pigment from head through dorsal and adipose fins to procurrent caudal fin rays; dorsal fin dusky, occasionally with pigment at apical tip (Ref. 80290).