Stegastes adustus, commonly called the dusky damselfish or scarlet-backed demoiselle, is a damselfish of the family Pomacentridae. It is found at one- to three-meter depths on surging and wavy coral reefs in the Caribbean Sea, the tropical waters of the western Atlantic Ocean, and the Gulf of Mexico.
Adults feed on plants and detritus.
Froese, Rainer, and Daniel Pauly, eds. (2008). "Stegastes adustus" in FishBase. December 2008 version.