ACANTHURIDAE Acanthurus leucosternon, 8.0 cm SL (photo by Ukkrit Satapoomin) Acanthurus leucosternon Bennett, 1833 Powder Blue Surgeonfish D IX, 28-30; A III, 26-28; P1 15-16; GR 16-20. Body deep, 1.7-1.9 in SL. Teeth fixed, denticulate on all of margin, with expanded incurved tips. Caudal fin emarginate, the caudal concavity 10-16 in SL. Caudal peduncle with 1 folding spine. Color: body blue with a broad white band crossing anterior chest from pectoral-fin base; caudal peduncle and spine yellow; head black; a white line extending from above corner of moth around chin; dorsal fin yellow with a white margin and black submarginal line; anal fin gray with a white margin and narrow white basal band; caudal fin black with a large crescentic central white region and a white posterior margin. Size: attaining to 23 cm. Distribution: Indo-West Pacific, ranging from East Africa to southern Indonesia. Remarks: generally found on coral reefs in less than 15 m.