Body laterally flattened, oval in profile, dark olive-brown to almost black, with a pale olive area behind the head. Faint dark bands on the body. Normally with a blackish area at the upper edge of the pectoral fin base. Dorsal and anal fins rounded and rarely extend beyond the base of the tail. May have a light blue outline on the rear dorsal and anal fins.
Juveniles bluish silver-gray, with a brilliant orange wash from the snout across the nape to about halfway the dorsal fin. Blue dot markings on the head and back. A dark spot on the dorsal fin and one on the base of the tail, both ringed in white to pale blue.
Size up to 12.5 cm.
Inhabit shallow reefs or rocky bottom, down to 12 m. Sometimes near the shore in areas with little visibility. A diurnal species, feeding on benthic algae, polychaetes and harpacticoid copepods. Adults also consume hydroids, sponges and eggs of other fish. Territorial, pugnaciously chase away intruders.
Occasional Florida, Bahamas and Caribbean.