Body very deep and compressed. Small head with a pointed snout. Small mouth with close-set of 12-14 denticulate teeth in juveniles and 18-22 in adults. Head profile convex. A continuous dorsal fin the spine increasing in size, 1st-5th rays are the longest and then decrease in size toward the caudal peduncle. Ana fin opposite the dorsal fin and originating slightly behind it. Caudal fin round to truncate. The upper pectoral rays are the longest. Pelvic fin below pectoral fin and slightly pointed. A lancet-like horizontal spine on each side of the caudal peduncle, folding to a shallow groove.
8-16 cm (max 20 cm)
Young Acanthurus coeruleus - blue edge on dorsal, anal and caudal fins and blue ring around the eye. Snout only slightly pointed.
Other Mediterranean spp. - Lack of sharp horizontal lancet-like spine on each side of the caudal peduncle.
BIOLOGY / ECOLOGY
Feeds on algae and seagrass. Eggs and larvae planktonic.
Shallow waters in the vicinity of rocks and corals.