Acanthurus xanthopterus Valenciennes, 1835
Yellowfin surgeonfish
黃鰭刺尾鯛,  倒吊,  粗皮仔
Acanthurus xanthopterus
photo by Alban Choinier/Magazine des Voyages de Pêche

Family:  Acanthuridae (Surgeonfishes, tangs, unicornfishes), subfamily: Acanthurinae
Max. size:  70 cm TL (male/unsexed); max. reported age: 29 years
Environment:  reef-associated; marine; depth range 1 - 100 m
Distribution:  Indo-Pacific: coast of East Africa to the Hawaiian Islands and French Polynesia, north to southern Japan, south to the Great Barrier Reef and New Caledonia. Eastern Pacific: lower Gulf of California and Clipperton Island to Panama and the Galapagos Islands.
Diagnosis:  Dorsal spines (total): 8-9; Dorsal soft rays (total): 25-27; Anal spines: 3-3; Anal soft rays: 23-25. Body purplish gray when alive; grayish brown when preserved; a region of dull yellow in front of eye, a lesser extension posterior to lower part of eye; outer 1/3 of pectoral fin yellow, extreme distal part hyaline; dorsal and anal fins yellowish grey basally, dull yellow distally; caudal fin base whitish; caudal fin purplish. Anterior gill rakers 16-24, posterior 17-22. Caudal spine small. Description: Characterized further by having length of caudal spine 4.4-5.7 in head length; greatest depth of body 1.9-2.3 in SL (Ref. 90102).
Biology:  Live in various reef habitats, sand slopes and lagoons (Ref. 48637). Juveniles inhabit shallow, protected, turbid inshore waters while adults prefer deeper areas of protected bays and lagoons. Also in outer reef areas (Ref. 1602). Benthopelagic (Ref. 58302). Schooling species, feed on diatoms, detritus film of sand, filamentous algae, hydroids, and pieces of fish (Ref. 1602, 48637). Probably the only surgeonfish that readily takes bait (Ref. 12484).
IUCN Red List Status: Least Concern (LC); Date assessed: 04 May 2010 Ref. (130435)
Threat to humans:  venomous
Country info:  Reported from northern (occasionally found in Yehliu (Ref. 43538)), southern (rarely found in Nanwan (Ref. 43538)), and western Taiwan (including Yun-gan (Ref. 43515) and Hsiao-liu-chiu) and from Penghu, Lanyu and Green islands (Ref. 48445, 48451). Also Ref. 37792, 43515, 47843, 55073.


Source and more info: www.fishbase.org. For personal, classroom, and other internal use only. Not for publication.