Diagnosis: body compressed and deep (depth comprised from 2.3 to 2.8 times in fork length) (Ref. 57392), its ventral profile distinctly more convex than the dorsal (Ref. 26938, 57392). Snout very short, its tip blunt, upper jaw extending almost to behind level of anterior eye margin; 2 dorsal fins, the first with 8 spines, the second with 1 spine and 25-28 soft rays; anal fin with 2 detached spines, followed by 1 spine and 25-28 soft rays; upper lobe of caudal fin longer than the lower; small, cycloid scales covering most of body, including chest; 5-15 weak scutes on posterior part of lateral line, at level of caudal peduncle, the latter without bilateral keels (Ref. 57392). Metallic blue above, silvery below; caudal peduncle with black saddle spot (Ref. 3197).
Coloration: back greenish or bluish, sides silvery-white; a dark, saddle-shaped blotch on caudal peduncle just before caudal fin, and another at upper angle of gill cover (Ref. 57392).