Whitecheek Surgeonfish

Acanthurus nigricans, is a reef-associated tang found from the central Indo-Pacific area to the eastern Pacific coast, Hawaii included.

Other names: Goldenrim Surgeonfish, Yellow-spotted Surgeonfish, Goldrim Surgeonfish, Velvet Surgeonfish, Yellow-banded Surgeonfish or Yellowrimmed Surgeonfish.

Description

It has a black to purplish-blue body with a small white mark on the cheek between the mouth and eyes. The pectoral, anal, and dorsal fins are dark blue with blue highlights at the tip. The tail is blue with a yellow vertical bar. A yellow striping runs along the body, against the anal and dorsal fins, forming a distinctive wishbone-shaped marking.

It grows to 21.3 cm in length.

Distribution

Eastern Indian Ocean: known only from Cocos-Keeling Islands and Christmas Island. Pacific Ocean: Ryukyu Islands and Great Barrier Reef to the Hawaiian Islands and French Polynesia (excluding Rapa). This species has crossed the Eastern Pacific Barrier to the Revillagigedo Islands, Cocos Island, Galapagos Islands, and the coast of Mexico.

Habitat

Adults inhabit hard substrate areas of clear lagoon and seaward reefs from the lower surge zone to at least 67 m and feeds on filamentous algae. Solitary or in groups. Monogamous. Benthopelagic. Small juveniles shy among large corals. Territorial species. Common throughout Micronesia and hybridizes with the rare A. achilles. Size of metamorphosis from the postlarva stage to juvenile is 5.5 to 6 cm.