Habitat: Marine. Coral reefs, 2-30 m. Juvenils also seen in grassy areas. Natural History Notes: Omnivorous, adults feed on sponges, tunicates, zoantharian and algae. Juveniles feed mainly on algae and detritus, occasionaly remove ectoparasites from other fishes. Characteristics: Adults : body showing different shades of grey. Caudal fin truncate to concave with a pale margin. Upper surfaces of pectoral fins yellow. Juveniles : black with two yellow bars on body and three on head and one on foretail. Caudal fin yellow with with white to transparent margin and a vertically elongate, nearly rectanglar or hemispherical black spot in middle. Forehead yellow band extends accross lips to chin.