The Powder Brown Tang (Acanthurus nigricans), also known as the goldrim surgeonfish, velvet surgeon, whitecheek surgeonfish, yellow-banded surgeonfish, or yellowrimmed surgeonfish, is a species of marine ray-finned fish belonging to the family Acanthuridae. It was first formally described by Linnaeus in 1758. The specific name nigricans means ‘swarthy’ or ‘blackish’, a reference to the bluish-black colour of this fish’s body. This species forms a species complex with A. achilles, A. japonicus, and A. leucosternon, and frequently hybridises with them.

Physical Description

The Powder Brown Tang has a body shaped like an elongated oval with a steep dorsal profile to the head and an eye positioned high on the head. The dorsal fin is supported by 9 spines and between 28 and 31 soft rays while the anal fin contains 3 spines and 26 to 28 soft rays. The overall colour is bluish-black or black broken by a large patch of white below the eye. There is a yellow band at the base of both the dorsal and anal fins and this widens as it approaches the caudal fin. The caudal peduncle has a patch of yellow around the spine and its sheath. The caudal fin is white with a slender yellow submarginal band. This species has a maximum published fork length of 36 cm (14 in).

Distribution and Habitat

The Powder Brown Tang is found from the central Indo-Pacific to the eastern Pacific coast, Hawaii included. It is found as far east as the Chagos Islands in the central Indian Ocean, Christmas Island and the Cocos Islands. In the Pacific it is found from the Ryukyu Islands of southern Japan south to the Great Barrier Reef and east across the Pacific to the eastern coasts of Central and South America. It is a benthopelagic fish with adults found at depths from the surface down to 67 m over hard substrates in clear waters in lagoons and over seaward reefs.

Diet and Feeding

The Powder Brown Tang is herbivorous, grazing on benthic algae.

Aquarium Care

The Powder Brown Tang requires a well-established aquarium of at least 100 gallons with excellent water quality. It is semi-aggressive and may display territorial behavior toward other tangs. Generally considered reef-safe.

Conservation Status

Classified as Least Concern by the IUCN Red List.