Yellowfin surgeonfish, Ringtail surgeonfish
  • Acanthurus xanthopterus
  • English Name : Yellowfin surgeonfish, Ringtail surgeonfish
  • Local Name : Vilu kaalhu
  • Size : Max. 65 cm
  • Family : ACANTHURIDAE
  • Order : Perciformes
  • Distinctive Characters: Dorsal fin with 9 spines and 25-27 rays. Anal fin with 3 spines and 23-25 rays. Pectoral rays 16 or 17. Body depth 2.0-2.3 in standard length. Caudal spine 4.5-5.5 in head length. Caudal fin lunate. Gill rakers 16-22.
  • Colour: Pale grey; dull yellow around eye; dorsal and anal fins dull yellow with four longitudinal broad blue bands; outer third of pectoral fin yellow; base of caudal fin often dull white.
  • Habitat and Biology: Usually observed in deeper lagoons dominated by sand, generally at depths greater than 10 m. Feeds on benthic algae.
  • Distribution: Indo-Pacific and Tropical Eastern Pacific.
  • Remarks: Acanthurus xanthopterus is perhaps the largest of the surgeonfishes. Occurs in schools and is very common in deep lagoons (“vilu”). This species has been previously called as A. matoides.