Blue tang
Acanthurus coeruleus
Bloch & Schneider, 1801

Description:
Body thin, oval in shape, with relatively long dorsal and anal fins and a crescent tail. Body blue overall, but can change from powder blue to deep purple, and pale or darken (A. coeruleus adult). Dorsal and anal fins edged in bright blue.
Base of tail with a sharp spine (like a surgeon's scalpel), white or yellow in color.
Juveniles bright yellow overall (A. coeruleus juvenile), intermediate with a blue head and body, but with a yellow tail. Changes from juvenile to intermediate and adult color phase are independent of the size, and sometimes a yellow phase juvenile may be larger than a blue-phased adult.
Size up to 39 cm.

Habitat:
Inhabits coral reefs, inshore grassy or rocky areas, down to 40 m. Can be solitary, but more often in large aggregations grazing on algae. Mainly diurnal. The sharp spines on both sides of the base tail are used as defensive weapons by slashing their tails from side to side. When not in use, they are folded backwards against the body.

Distribution:
Abundant to common Florida, Bahamas and Caribbean.

Remarks:
Body more circular than in the Ocean surgeonfish (Acanthurus bahianus) and Doctorfish (Acanthurus chirurgus).

Kingdom Animalia
Phylum Chordata
Superclass Pisces
Class Osteichthyes
Family Acanthuridae
Genus Acanthurus
Species Acanthurus coeruleus

Status in World Register of Marine Species

Accepted name: Acanthurus coeruleus Bloch & Schneider, 1801

Scientific synonyms and common names

Blue tang [English]
Chirurgien bayolle [French]
Blauer Doktorfisch [German]
Kleinfeshi blou [Papiamentu]

Humann, P., 1989. Reef Fish Identification - Florida Caribbean Bahamas, (ed. N. Deloach). New World Publications, Inc., Paramount Miller Graphics, Inc., Jacksonville, Florida.

Nagelkerken, W., 1980. Coral Reef Fishes of Aruba, Bonaire and Curaçao. Published by the Island Territory of Curacao.

You can continue searching for Acanthurus coeruleus on one of these Web sites:

Fauna Europaea (animals) | IOPI (plants) | NCBI (genetic)

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