Pempheris adusta, the dusky sweeper, is a species of marine ray-finned fish in the family Pempheridae, the sweepers. It is common species on coral reefs in the Indo-Pacific region.

Description Pempheris adusta has 6 spines in its dorsal fin which also has 8-10 soft rays, the anal fin has 3 spines and 36-45 soft rays, this species also has 25 vertebrae. It is distinguished from related species by having a blackish spot at the base of the pectoral fin, a lateral-line with 56-64 pored scales, 4.5-6.5 scale rows above the lateral line, there is a distinct blackish band on the margin of the anal fin, and they have blackish band on margin of the caudal fin. The largest recorded total length is 17 cm (6.7 in).

Distribution Pempheris adusta has an Indo-Pacific distribution which extends from the Red Sea and the eastern coast of Africa through the Indian Ocean to the western central Pacific Ocean.

Habitat and biology Pempheris adusta has a depth range of 0–20 m (0–66 ft) and it is a common species of coral reefs where it forms aggregations during the day in caves or crevices or below overhangs. A few can sometimes be seen out in the open in the day, near the shelter provided by reefs. It has been recorded in small groups with Myripristis murdjan less than 1 m (3 ft) below the surface. It emerges from its shelters at night to feed on zooplankton.