Description:

Dorsal spines: 8-9; Dorsal rays: 25-27; Anal spines: 3; Anal rays: 23-25.
Purplish-grey body often with alternating, irregular, lengthwise stripes of dark yellowish grey and light blue-grey. Dull yellow band in front of eye with narrower 
extension running behind eye (sometimes continuing faintly posterior of operculum to pectoral fin base). Pectoral fin yellow contrasting against grey body. Dorsal 
and anal fins dull yellow with pale blue band at base and dark longitudinal bands. Base of lunate caudal fin whitish with fin itself purplish. Small caudal spine 
with light blue socket. 

Maturity: Lm unknown. Range unknown. Max Length: 70cm TL largest species in the genus. Common length 50cm TL.

Lives in various reef habitats, sandy substrates and lagoons (depth 1-90m)  and usually in depths greater than 10m. Juveniles recruit to shallow, protected, turbid 
inshore waters, while adults are found in deeper areas of protected bays, lagoons and outer reefs. This species feeds on sediment, algae and detritus. May occur 
as individually or in schools. 

This species is not protected or subject to fishery regulations. It is caught in the fish trap fishery. May also be taken by hook on occasion.

Venomous spine. Large catches were recorded off Mahe on September 12th 2018 (week of the new moon) suggesting aggregation behaviour.
 

Abesamis, R. et al. (2012). Acanthurus xanthopterus. The IUCN Red List 2012: e.T177989A1512937. http://dx.doi.org/10.2305/IUCN.UK.2012.RLTS.T177989A1512937.en. (15/10/18).
Froese, R. & D. Pauly. Eds. (2018). FishBase. https://www.fishbase.de/summary/Acanthurus-xanthopterus (15/10/18)
Randall, J.E. (2001). Surgeonfishes of Hawaii and the World. ISBN: 1-56647-561-9
Nevill, J.E.G. (2013). A Species Identification Guide for Commonly Caught Fish in the Seychelles Near-Shore Artisanal Fishery. GOS/UNDP/GEF.

Nevill, J.E.G. (2019). Acanthurus xanthopterus, Yellowfin surgeonfish. Seychelles Seatizens. www.seatizens.sc. https://seatizens.sc/species/acanthurus-xanthopterus-valenciennes-1835/ (edited 15/06/22).