Acanthurus blochii Valenciennes 1835

Color in life bluish grey with numerous yellowish brown spots which tend to form irregular longitudinal lines; head with narrow irregular stripes; behind eye a yellow spot; brown pectoral fins; base of caudal fin with white bar. Caudal spine large, 3 - 4.4 in head. Stomach gizzard-like. Differs from A. dussumieri by having vertical stripes instead of spots on the blue central area of the caudal fin, from A. mata by having a lunate caudal fin, and from A. xanthopterus by having plain brown to blue-grey pectoral fins (Ref. 1602). The white ring around the base of the tail varies in intensity and may occasionally be absent (Ref. 1602).

Dorsal spines (total): 9; Dorsal soft rays (total): 25 - 27; Analspines: 3; Analsoft rays: 24 - 25

Adults occur in outer lagoon and seaward reefs, usually seen in small groups and school in some oceanic locations (Ref. 48637). Benthopelagic (Ref. 58302). They feed primarily on the algal film covering compacted sand, ingesting the usual component of sand which probably aids in the trituration of the algal food in the thick-walled stomach, also feed on diatoms and detritus (Ref. 3921).

fisheries: commercial; aquarium: commercial