Latin name

Acanthurus bahianus

Other names

Ocean surgeonfish, Acanthurus bahianus

Identification

Known for their oval bodies of uniform colouration (usually blue-grey to dark brown), pale to dark markings around the eyes, and now a light yellow colouration found on their bodies. Most have blue or white markings on their dorsal, anal and caudal fins, and sometimes pale stripes can be seen at the base of the tail. They have a total of 9 spines on their dorsal fins and 23 to 26 soft rays. The anal fins have a total of 3 spines and 21 to 23 rays. The caudal fins are roughly pointed and the body and head are deep and compressed.

Distribution

In the southern and central Atlantic, the surgeonfish can be found along the Brazilian coast from the state of Maranhão south to Santa Catarina.

Habitat

The habitat of this fish is coral reefs and rocky coastal areas, usually where there are sandy areas. They often swim in schools with other species such as the Atlantic Blue Tang Surgeonfish. They can be found at depths from 2 to 40 metres offshore, usually down to 25 metres.

Size

They have been recorded to reach 38 centimetres in length. 

Life history and Behavior

This species forms breeding aggregations of up to 20,000 individuals. They live up to 31 years.

Food and feeding habits

They live on coral reefs where they feed on algae.

Reproduction

They do not form stable pairs like almost all other Acanthurus. Males defend a small territory against intruders. The pelagic larval stage lasts from 42 to 68 days and the larva adopts a benthic lifestyle at a length of 26.9 mm. Sexual maturity is reached at the age of one year and at a length of 11 to 16 cm.