Distinctive Characters: Dorsal fin with 12 spines and 24-26 rays. Anal fin with 3 spines and 20-21 rays. Pectoral fin with 17 rays. Body depth 1.5 in standard length.
Colour: Dark brown with broad white area in middle of the body. Dorsal spines over white area are yellow. Caudal fin mostly white.
Habitat and Biology: Commonly found at depths 1-35 m. Usually seen in large schools. Feeds on zooplankton well above the corals, to which it retreats at the approach of danger.
Distribution: Western Indian Ocean.
Remarks: Hemitaurichthys zoster is very common in the Maldives. It is unusual for a butterflyfish in that it feeds mainly on plankton, and presumably for this reason has adopted a schooling mode of life unlike most of the butterflyfishes.