Body oval, compressed; 1 pair of nostrils; margin of preopercle serrated; margin of bone under eye serrated, without notch it and the bone before it; mouth small, protrusible; teeth in single row, long and close-set; lower gill rakers 12-14; a single continuous dorsal fin, XII, 15 (rarely 16); anal rays II, 13 (rarely 12); pectoral rays 20 (rarely 19); no projecting short spines at upper and lower base of tail fin; caudal fin bluntly forked; scales are moderately large and rough; body scaled, head largely scaled (snout scaled to nostrils), as are the basal parts of the median fins; lateral-line scales 20 (rarely 19); lateral line incomplete, ends under end of dorsal fin base.
Dark brown, head and breast lighter, often with violet color on gill cover; pale yellowish lips; tail fin bright yellow; juveniles similar, but yellow of tail extends forward onto posterior part of body and rear of dorsal and anal fins; a large ocellated black spot near the base of the front of the soft dorsal.
Size: to 16 cm.
Habitat: abundant along rocky shores.
Depth: 1-30 m.
Galapagos Islands, Malpelo Island, and Isla del Coco, Isla Gorgona (Colombia) and Isla de la Plata (Ecuador).