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 Many have eyespots on their flanks and dark bands across their eyes, not unlike the patterns seen on butterfly wings. Their deep, laterally narrow bodies are easily noticed through the profusion of reef life. The conspicuous coloration of butterflyfish may be intended for interspecies communication. Butterflyfish have uninterrupted dorsal fins with tail fins that may be rounded or truncated, but are never forked.

Generally diurnal and frequenting waters less than deep (though some species descend to , butterflyfish stick to particular home ranges. These corallivores are especially territorial, forming pairs and staking claim to a specific coral head. Contrastingly, the zooplankton feeders form large conspecific groups. By night, butterflyfish hide in reef crevices and exhibit markedly different coloration.

Their coloration also makes them popular aquarium fish. However, most species feed on coral polyps and sea anemones. 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. They lose their bony plates as they mature.

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. This clade contains 7 families which appear to have some relationship to Acanthuroidei, Monodactylidae, and Priacanthidae. Other authorities have paced the family in the order Chaetodontiformes alongside the family Leiognathidae. Presently, based on the most recent phylogenetic analyses, Eschmeyer's Catalog of Fishes places it in the large, diverse order Acanthuriformes. Molecular analyses suggest that the Chaetodontidae shared a common ancestor with the Scatophagidae and Pomacanthidae that lived during the Early Eocene (54 Ma).

Before DNA sequencing, the taxonomy was confused about whether to treat these as species or subspecies. Also, numerous subgenera have been proposed for splitting out of Chaetodon, and it is becoming clear how to subdivide the genus if that is desired.

Fossil record

The fossil record of this group is disputed and marginal. Their restriction to coral reefs means their carcasses are liable to be dispersed by scavengers, overgrown by corals, and any that do fossilize will not long survive erosion. Many Eocene-aged fish such as Pygaeus have been variously referred to Chaetodontidae in the past; if used for calibration, it can be deduced that most living genera were probably distinct by the end of the Paleogene 23 Mya. However, these Eocene genera cannot be reliably referred to Chaetodontidae.

  • Family Chaetodontidae <small>Rafinesque, 1815</small>
  • Subfamily Heniochinae <small>Kaup</small><small>, 1860</small> (bannerfishes and coralfishes)
  • Amphichaetodon <small>Burgess, 1978</small>
  • Coradion <small>Kaup, 1860</small>
  • Chelmon <small>Cloquet, 1817</small>
  • Chelmonops <small>Bleeker, 1876</small>
  • Forcipiger <small>Jordan & McGregor, 1898</small>
  • Hemitaurichthys <small>Bleeker, 1876</small>
  • Heniochus <small>Cuvier, 1816</small>
  • Johnrandallia <small>Nalbant, 1974</small>
  • Subfamily Chaetodontinae <small>Rafinesque, 1815</small>
  • Chaetodon <small>Linnaeus, 1758</small>
  • Prognathodes <small>Gill, 1862</small>
  • Subfamily incertae sedis
  • Parachaetodon <small>Bleeker, 1874</small>
  • Roa <small>Jordan, 1923</small>

Timeline

<timeline>

ImageSize = width:1000px height:auto barincrement:15px

PlotArea = left:10px bottom:50px top:10px right:10px

Period = from:-66 till:10

TimeAxis = orientation:horizontal

ScaleMajor = unit:year increment:5 start:-66

ScaleMinor = unit:year increment:1 start:-66

TimeAxis = orientation:hor

AlignBars = justify

Colors =

  1. legends

id:CAR value:claret

id:ANK value:rgb(0.4,0.3,0.196)

id:HER value:teal

id:HAD value:green

id:OMN value:blue

id:black value:black

id:white value:white

id:cenozoic value:rgb(0.54,0.54,0.258)

id:paleogene value:rgb(0.99,0.6,0.32)

id:paleocene value:rgb(0.99,0.65,0.37)

id:eocene value:rgb(0.99,0.71,0.42)

id:oligocene value:rgb(0.99,0.75,0.48)

id:neogene value:rgb(0.999999,0.9,0.1)

id:miocene value:rgb(0.999999,0.999999,0)

id:pliocene value:rgb(0.97,0.98,0.68)

id:quaternary value:rgb(0.98,0.98,0.5)

id:pleistocene value:rgb(0.999999,0.95,0.68)

id:holocene value:rgb(0.999,0.95,0.88)

BarData=

bar:eratop

bar:space

bar:periodtop

bar:space

bar:NAM1

bar:NAM2

bar:space

bar:period

bar:space

bar:era

PlotData=

align:center textcolor:black fontsize:M mark:(line,black) width:25

shift:(7,-4)

bar:periodtop

from: -66 till: -55.8 color:paleocene text:Paleocene

from: -55.8 till: -33.9 color:eocene text:Eocene

from: -33.9 till: -23.03 color:oligocene text:Oligocene

from: -23.03 till: -5.332 color:miocene text:Miocene

from: -5.332 till: -2.588 color:pliocene text:Plio.

from: -2.588 till: -0.0117 color:pleistocene text:Pleist.

from: -0.0117 till: 0 color:holocene text:H.

bar:eratop

from: -66 till: -23.03 color:paleogene text:Paleogene

from: -23.03 till: -2.588 color:neogene text:Neogene

from: -2.588 till: 0 color:quaternary text:Q.

PlotData=

align:left fontsize:M mark:(line,white) width:5 anchor:till align:left

color:oligocene bar:NAM1 from: -28.4 till: 0 text: Chaetodon

color:miocene bar:NAM2 from: -23.03 till: 0 text: Chelmon

PlotData=

align:center textcolor:black fontsize:M mark:(line,black) width:25

bar:period

from: -66 till: -55.8 color:paleocene text:Paleocene

from: -55.8 till: -33.9 color:eocene text:Eocene

from: -33.9 till: -23.03 color:oligocene text:Oligocene

from: -23.03 till: -5.332 color:miocene text:Miocene

from: -5.332 till: -2.588 color:pliocene text:Plio.

from: -2.588 till: -0.0117 color:pleistocene text:Pleist.

from: -0.0117 till: 0 color:holocene text:H.

bar:era

from: -66 till: -23.03 color:paleogene text:Paleogene

from: -23.03 till: -2.588 color:neogene text:Neogene

from: -2.588 till: 0 color:quaternary text:Q.

</timeline>

<gallery>

Image:Seattle Aquarium, 1.JPG|Copperband butterflyfish, Chelmon rostratus

Image:Johnrandallia nigrirostris.jpg|The enigmatic Johnrandallia nigrirostris

Image:Chaetodon kleinii.jpg|Sunburst butterflyfish, (sometimes placed in Lepidochaetodon)

Image:Bep chaetodon bennetti.jpg|Bluelashed butterflyfish, Chaetodon bennetti (sometimes placed in Megaprotodon)

</gallery>

Further reading

  • Pratchett, Morgan S. & Berumen, Michael L. & Kapoor, B.G. [Editors] : Biology of Butterflyfishes. CRC Press, 2014.

References

;General

  • (2007): Molecular phylogenetics of the butterflyfishes (Chaetodontidae): Taxonomy and biogeography of a global coral reef fish family. Mol. Phylogenet. Evol. 45(1): 50–68. <small></small> (HTML abstract)
  • [2008]: Family Chaetodontidae – Butterflyfishes. Retrieved 2008-SEP-02.
  • Raffles Bulletin of Zoology Supplement 2007
  • (2002): [Chaetodon]. In: A compendium of fossil marine animal genera. Bulletins of American Paleontology 364: 560. HTML database excerpt

;Specific