Latin name

Acanthurus xanthopterus

Other name

Ringtail surgeonfis, cuvier's surgeonfish.

Identification

Anterior gill lobes 16-24, posterior 17-22. Caudal process small.

Features of fish fins

These fish have eight or 9 dorsal spines, 25-27 dorsal soft rays, three anal spines, 23-25 anal soft rays, and 16-24 anterior rays.

Fish colouring

The body is purplish gray. Dull yellow area in front of eyes. Outer third of pectoral fin yellow, distal part hyaline. The dorsal and anal fins are yellowish gray at the base and pale yellow in the distal part. The caudal fin is purplish. 

Distribution

Widespread from East Africa to Hawaii and French Polynesia, north to southern Japan, south to the Great Barrier Reef and New Caledonia, and in the eastern Pacific from the lower Gulf of California and Clipperton Island to Panama and the Galapagos Islands.

Habitat

A marine tropical species. They live near coral reefs at depths of 5 to 90 m (16-295 ft). Their preferred temperature is 24-28°C (75-82°F) at latitudes from 30°N to 30°S. 

Size

Acanthurus xanthopterus reaches a length of 70 cm (28 inches). Normal length is 50 cm. Maximum reported age: 29 years.

Behavior

Juveniles inhabit shallow, sheltered, turbid coastal waters, while adults prefer deeper areas of sheltered bays and lagoons.

Food and feeding habits

They feed on diatoms, detritus, filamentous algae, hydroids and bits of fish. 

Reproduction

The male chases the female until she pays attention to him, after which the act of fertilization takes place. Once the female lays the eggs and they are fertilized, the cubs are born in about three days, depending on the temperature.

Fishing

Probably the only surgeonfish that willingly takes bait. Of negligible commercial importance.

Relationship with a person

A poisonous species.