Orangeband Surgeonfish

Max length : 35.0 cm TL male/unsexed

Family	Acanthuridae
Description	Surgeonfishes, tangs, unicornfishes
Environment	Marine
Etymology	Greek, akantha = thorn + oura = tail
Genus	6
No. of Species	82
Order	Perciformes
Class	Actinopterygii
Reproductive Guild	Nonguarders
Distribution	Circumtropical, especially around coral reefs; five species in the Atlantic, the remaining in the Pacific and Indian oceans. All have a deep compressed body with the eye high on the head and a long preorbital bone. Single unnotched dorsal fin with 4-9 spines and 19-31 rays; anal fin with 2 (only Naso) or 3 spines and 19-36 rays; pelvic fins with 1 spine and 3 (Naso and Paracanthurus) or 5 rays. Very small ctenoid scales. A small terminal mouth with a single row of close-set teeth. Most surgeon fishes graze on benthic algae and have a long intestine; some feed mainly on zooplankton or detritus. Surgeon fishes are able to slash other fishes with their sharp caudal spines by a rapid side sweep of the tail. Pelagic spawners. Many species have bright colors and are popular aquarium fishes.

Inhabit seaward reefs, in areas of bare rock or mixed rubble and sand, from 9 to at least 46 m depth; juveniles inhabit protected bays and lagoons, singly or in small groups in as little as 3 m. Benthopelagic. Adults occur singly or in schools and feed on surface film of detritus, diatoms, and fine filamentous algae covering sand and bare rock. Rarely poisonous

Dorsal spines (total): 9; Dorsal soft rays (total): 23-25; Anal spines: 3; Anal soft rays: 22 - 24. Body of adult dark grayish brown; juveniles yellow; posterior to upper end of gill opening is a bright orange horizontal band, with purplish black border. Head and anterior half of body usually abruptly paler than the posterior half. Anterior gill rakers 24-28; posterior 23-27. Large adult males (about 17 cm) with more definite convexity of snout profile.

Summary of Distribution: Pacific Ocean: Christmas Island and Cocos-Keeling Islands in the eastern Indian Ocean to the Hawaiian and Tuamoto islands, north to Japan, south to Lord Howe Island. Replaced by Acanthurus tennenti in the Indian Ocean
Note: Distribution range colors indicate degree of suitability of habitat which can be interpreted as probabilities of occurrence (fishbase.org)