Hemitaurichthys zoster is one of the 4 members belonging to the genus Hemitaurichthys, which together with 11 additional genera make up the butterflyfishes family (Chaetodontidae) in which a total of 129 species are currently described. This species is widely distributed in tropical and subtropical waters of both the Indian and Pacific Oceans, occurring from the east coast of Africa to Indonesia in the Indian Ocean and from India to the Mauritius Islands in the Pacific. Generally, this species is usually found in waters between 2 and 40 meters deep in lagoons, reefs and rocky slopes.
The body of Hemitaurichthys zoster is flattened, more or less oval in shape and laterally compressed, that is to say it has the typical physiognomy of a butterflyfish. It has a relatively small rostrum that gives it a somewhat stubby appearance. The mouth is narrow and pointed. They can grow up to 18 cm in total length. They have 12 spines on the dorsal fin and 24-26 soft rays, while the anal fin has 3 spines and 21 soft rays.
The base coloration of the body of Hemitaurichthys zoster is dark brown, sometimes blackish, with a wide pearl white vertical stripe that runs all the way across the body and is slightly wider at the base than at the top. The dorsal and anal fins are dark brown, except for the spines of the dorsal fin that coincide with the wide white spot, which are yellow. The pectoral and caudal fins are white.
Hemitaurichthys zoster is an omnivorous species that feeds on both algae and zooplankton. They usually form large aggregations of hundreds of individuals, as the schooling effect gives them some security to be able to move away from the corals where they live and feed on plankton.
During the reproductive season, pairs are formed that will release eggs and sperm into the water column, so that fertilization can occur and the dominant currents spread their small eggs over a vast territory.
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