Twinstripe Fusilier

Pterocaesio marri has a fusiform and elongated body which is moderately laterally compressed. There are small conical teeth in the jaws but none on the vomer and palatines. The dorsal fin contains 10-11 spines and 14-16 soft rays while the anal fin has 3 spines and 11-13 soft rays. There are scales on both the dorsal and anal fins. There are 2-24 rays in the pectoral fins. This species attains a maximum total length of 35 cm (14 in). The overall colour is blue with dark tips to the lobes of the caudal fin and two thin yellow to brownish stripes along the flanks, the lowest stripe largely running along the lateral line.

Pterocaesio marri has a wide range in the Indo-West Pacific. It is occurs along the coast of East Africa from Somalia south to South Africa, although it is absent from the Red Sea and the Persian Gulf. It is found east across the Indian Ocean into the Pacific Ocean as far east as the Marquesas Islands. It has also been recorded in New Caledonia, Fiji and Tonga and south to the northern Great Barrier Reef of Queensland and the reefs in the Coral Sea, as well as Christmas Island. This species occurs at depths between 1 and 35 m (3 ft 3 in and 114 ft 10 in) on reefs and around oceanic islands.