The common name references the brightly coloured and strikingly patterned bodies of many species, bearing shades of black, white, blue, red, orange, and yellow.

Butterflyfish are a boundless, different group of marine percoids with delegates on practically all coral reef frameworks and in every single tropical ocean.

Balancing the relative populations of prey and predator is complex, leading hobby aquarists to focus on the few generalists and specialist zooplankton feeders.

Butterflyfish are pelagic spawners; that is, they release many buoyant eggs into the water, which become part of the plankton, floating with the currents until hatching.

The fry go through a tholichthys stage, wherein the body of the postlarval fish is covered in large, bony plates extending from the head.

[5] Chaetodontidae is classified within the suborder Percoidei by the 5th edition of Fishes of the World, but they are placed in an unnamed clade which sits outside the superfamily Percoidea.

However, Pygaeus, a very basal fossil from the mid- to late Eocene of Europe, dates from around the Bartonian 40–37 million years ago (Mya).

A crude molecular clock in combination with the evidence given by Pygaeus allows placement of the initial split between the two main lineages to the middle to late Eocene, and together with the few other fossils, it allows the deduction that most living genera were probably distinct by the end of the Paleogene 23 Mya.