Black-Barred Surgeonfish

Acanthurus polyzona

The black-barred surgeonfish, also known as the zebra tang, is a tropical reef fish found in the western Indian Ocean. It has a distinctive appearance with a laterally flattened, almond-shaped body that can grow up to 20 cm in length. The fish is characterized by its pale yellow to olive-grey dorsal coloration, transitioning to a silvery-white ventrally. Nine broad black bands run vertically across its body, with the first band passing through the eye and the last two located on the caudal peduncle. These bands help differentiate it from the similar convict tang, which has fewer and more slender bands. This species inhabits shallow reef environments, including lagoons and outer reef slopes, at depths of up to 15 meters. Its distribution is limited to the tropical western Indian Ocean, specifically around Madagascar, Mauritius, Réunion, and the Comoro Islands. The black-barred surgeonfish is diurnal and primarily feeds on filamentous algae. It often forms associations with shoals of convict tangs, benefiting from the safety in numbers. While the reproduction of the black-barred surgeonfish has not been extensively studied, juveniles are known to grow rapidly, potentially doubling a population within 15 months. The IUCN Red List categorizes this species as Data Deficient.