Pomacanthidae in the context of Perciform

The butterflyfish are a group of conspicuous tropical marine fish of the family Chaetodontidae; the bannerfish and coralfish are also included in this group. The approximately 129 species in 12 genera are found mostly on the reefs of the Atlantic, Indian, and Pacific Oceans. A number of species pairs occur in the Indian and Pacific Oceans, members of the huge genus Chaetodon.

Butterflyfish look like smaller versions of angelfish (Pomacanthidae), but unlike these, lack preopercle spines at the gill covers. Some members of the genus Heniochus resemble the Moorish idol (Zanclus cornutus) of the monotypic Zanclidae. All three families belong to the order Acanthuriformes and share a similar habitat.

Acanthuriformes is a large, diverse order of mostly marine ray-finned fishes, part of the Percomorpha clade. In the past, members of this clade were placed in the suborders Acanthuroidea and Percoidea of the order Perciformes, but this treatment is now considered paraphyletic.

This order contains many of the iconic tropical reef fish groups, such as surgeonfish, marine angelfish, butterflyfish, rabbitfish, grunts, and snappers. It also contains widespread, economically important food and sport fishes, such as drums, temperate basses, and porgies. The only pelagic member of the group is the louvar.