Rock flagtail

Dorsal spines (total): 10; Dorsal soft rays (total): 10-12; Anal spines: 3; Anal soft rays: 9-11. Diagnosis: Preorbital serrae 10-15 (obsolete in large specimens); body depth 2.6-3.0 in SL; mouth large for genus, maxilla reaching to below posterior half of eye; caudal fin emarginate, lobes somewhat rounded, caudal concavity 5.3-8.7 in head length (Ref. 41640). Reduced number of lateral line scales; 17-18(19) gillrakers on lower part of first bracnhial arch; body with spots (Ref. 79840). Coloration: Silvery, the scales dorsally on body with black edges, those on side with a black bar or spot; juveniles with a broad black zone, edged above and below in white, in soft portion of dorsal fin, and each lobe of caudal fin with a large, white-edged black spot; black areas in these fins enlarge with growth until in adults most of these fins black (caudal with upper and lower edges and corners whitish) (Ref. 41640).