Indo-Pacific: East Africa to the Hawaiian, Marquesan, and Pitcairn islands, north to the Ryukyu and Bonin islands, south to Lord Howe Island and Rapa. Unknown from the Red Sea, Persian Gulf and Gulf of Oman.
Adults are found clear water, inner to outer reef crests in rich coral habitat.
Common in passages, frequently associated with Acropora, Stylophora, or Pocillopora coral heads or a single head of Pocillopora eydouxi. Usually seen solitary.
Feed on benthic algae and probably coral polyps. Oviparous, distinct pairing during breeding.
Eggs are demersal and adhere to the substrate. Males guard and aerate the eggs.