Distinctive Characters: Dorsal fin with 9 spines and 30 rays. Anal fin with 3 spines and 28 rays. Pectoral fin with 2 spines and 14 rays. Pelvic fin with 1 spine and 5 rays. Strongly compressed oval shaped body. First dorsal fin and anal spine very short. Mouth small. Caudal fin emarginate.
Colour: Body blue with a black head and a white chin. Dorsal fin yellow with a black sub-marginal line. Caudal fin with two dark cross bands. Upper and lower edges of caudal fin white. Pectoral translucent yellow.
Habitat and Biology: A shallow-water outer reef species found to a depth of 10 m. Occasionally found in large feeding aggregations. These schools overwhelm territorial damselfishes guarding their private pastures of algae.
Distribution: Indian Ocean.
Remarks: Acanthurus leucosternon is a typical surgeonfish for the Indian Ocean. It is a very popular species among the aquarists, mainly due to its pleasing colour patterns.