The Moorish idol (Zanclus cornutus), is a marine fish species, the sole extant representative of the family Zanclidae (from the Greek ζαγκίος, zagkios, "oblique") in order Perciformes. A common inhabitant of tropical to subtropical reefs and lagoons, the Moorish idol is notable for its wide distribution throughout the Indo-Pacific. A number of butterflyfishes (genus Heniochus) closely resemble the Moorish idol. It is closely related to, if not a direct descendant of, the extinct Eozanclus brevirostris, from the Middle Eocene of Monte Bolca.