Chaetodon Temporal range: 28–0 Ma PreꞒ Ꞓ O S D C P T J K Pg N Late Oligocene? – Recent
Foureye butterflyfish, C. capistratus the type species of Chaetodon
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Acanthuriformes
Family:	Chaetodontidae
Genus:	Chaetodon Linnaeus, 1758
Type species
Chaetodon capistratus Linnaeus, 1758
Subgenera
Chaetodon Linnaeus, 1758 "Citharoedus" Kaup, 1860 (non Herrmannsen, 1847: preoccupied) Corallochaetodon Burgess, 1978 Discochaetodon Nalbant, 1971 Exornator Nalbant, 1971 Gonochaetodon Bleeker, 1876 Lepidochaetodon Bleeker, 1876 Megaprotodon Guichenot, 1848 Rabdophorus Swainson, 1839 Rhombochaetodon Burgess, 1978 (disputed) Tetrachaetodon Weber & Beaufort, 1936 and see text
Synonyms
Aspilurochaetodon Mauge & Bauchot, 1984 Burgessius Mauge & Bauchot, 1984 Chaetodontops Bleeker, 1876 Heterochaetodon Mauge & Bauchot, 1984 Roaops Mauge & Bauchot, 1984 Tifia Jordan in Jordan & Jordan, 1922

Chaetodon is a tropical fish genus in the family Chaetodontidae. Like their relatives, they are known as "butterflyfish". This genus is by far the largest among the Chaetodontidae, with about 90 living species included here,^[1] though most might warrant recognition as distinct genera.

There are currently 87 recognized species in this genus:^[2]

• Chaetodon capistratus Linnaeus, 1758 (Foureye butterflyfish)
• Chaetodon ocellatus Bloch, 1787 (Spotfin butterflyfish)
• Chaetodon striatus Linnaeus, 1758 (Banded butterflyfish)

• Chaetodon hoefleri Steindachner, 1881 (Four-banded butterflyfish)
• Chaetodon robustus Günther, 1860 (Three-banded butterflyfish)

• 
  Spotband butterflyfish
  Chaetodon (Exornator) punctatofasciatus
• 
  Peppered butterflyfish
  Chaetodon (Exornator) guttatissimus
• 
  Fourspot butterflyfish
  Chaetodon (Exornator) quadrimaculatus
• 
  Teardrop butterflyfish
  Chaetodon (Lepidochaetodon) unimaculatus
• 
  Seychelles butterflyfish
  Chaetodon (Rhombochaetodon) madagaskariensis
• 
  Brownburnie
  Chaetodon (Rhombochaetodon) blackburnii
• 
  A group of Yellow teardrop butterflyfish
  Chaetodon (Lepidochaetodon) interruptus

Subgenus Exornator (including Burgessius, Heterochaetodon and possibly Rhombochaetodon; tentatively placed here)

• Chaetodon citrinellus G. Cuvier, 1831 (Speckled butterflyfish, Citron butterflyfish)
• Chaetodon dolosus C. G. E. Ahl, 1923 (African butterflyfish)
• Chaetodon guentheri C. G. E. Ahl, 1923 (Crochet butterflyfish)
• Chaetodon guttatissimus E. T. Bennett, 1833 (Peppered butterflyfish)
• Chaetodon miliaris Quoy & Gaimard, 1825 (Millet butterflyfish)
• Chaetodon multicinctus A. Garrett, 1863 (Pebbled butterflyfish)
• Chaetodon pelewensis Kner, 1868 (Sunset butterflyfish)
• Chaetodon punctatofasciatus G. Cuvier, 1831 (Spotband butterflyfish)
• Chaetodon quadrimaculatus J. E. Gray, 1831 (Fourspot butterflyfish)
• Chaetodon sedentarius Poey, 1860 (Reef butterflyfish)

Subgenus Lepidochaetodon (including Tifia)

• Chaetodon daedalma D. S. Jordan & Fowler, 1902 (Wrought-iron butterflyfish) (tentatively placed here)
• Chaetodon interruptus C. G. E. Ahl, 1923 (Yellow teardrop butterflyfish)
• Chaetodon kleinii Bloch, 1790 (Sunburst butterflyfish, black-lipped butterflyfish, Klein's butterflyfish)
• Chaetodon litus J. E. Randall & D. K. Caldwell, 1973 (Easter Island butterflyfish) (tentatively placed here)
• Chaetodon nippon Steindachner & Döderlein (de), 1883 (Japanese butterflyfish) (tentatively placed here)
• Chaetodon smithi J. E. Randall, 1975 (Smith's butterflyfish) (tentatively placed here)
• Chaetodon trichrous Günther, 1874 (Tahiti butterflyfish)
• Chaetodon unimaculatus Bloch, 1787 (Teardrop butterflyfish)

Subgenus Rhombochaetodon (including Roaops, might belong in Exornator; tentatively placed here)

• Chaetodon argentatus H. M. Smith & Radcliffe, 1911 (Asian butterflyfish)
• Chaetodon blackburnii Desjardins, 1836 (Brownburnie) (tentatively placed here)
• Chaetodon burgessi G. R. Allen & Starck, 1973 (Burgess' butterflyfish)
• Chaetodon declivis J. E. Randall, 1975 (Marquesas butterflyfish) (tentatively placed here)
• Chaetodon flavocoronatus R. F. Myers, 1980 (Yellow-crowned butterflyfish) (tentatively placed here)
• Chaetodon fremblii E. T. Bennett, 1828 (Blue-striped butterflyfish)
• Chaetodon madagaskariensis C. G. E. Ahl, 1923 (Seychelles butterflyfish)
• Chaetodon mertensii G. Cuvier, 1831 (Atoll butterflyfish)
• Chaetodon mitratus Günther, 1860 (Indian butterflyfish) (tentatively placed here)
• Chaetodon paucifasciatus C. G. E. Ahl, 1923 (Eritrean butterflyfish, Crown butterflyfish)
• Chaetodon tinkeri L. P. Schultz, 1951 (Hawaiian butterflyfish) (tentatively placed here)
• Chaetodon xanthurus Bleeker, 1857 (Pearlscale butterflyfish, Philippines chevron butterflyfish, yellow-tailed butterflyfish)

• 
  Ornate butterflyfish
  Chaetodon ("Citharoedus") ornatissimus
• 
  Mailed butterflyfish
  Chaetodon ("Citharoedus") reticulatus
• 
  Blacktail butterflyfish
  Chaetodon (Corallochaetodon) austriacus
• 
  Oval butterflyfish
  Chaetodon (Corallochaetodon) lunulatus
• 
  Eightband butterflyfish
  Chaetodon (Discochaetodon) octofasciatus
• 
  Eastern triangular butterflyfish
  Chaetodon (Gonochaetodon) baronessa
• 
  Chevron butterflyfish
  Chaetodon (Megaprotodon) trifascialis
• 
  Mirror butterflyfish
  Chaetodon (Tetrachaetodon) speculum
• 
  Zanzibar butterflyfish
  Chaetodon (Tetrachaetodon) zanzibarensis

Subgenus "Citharoedus" (tentatively placed here)

• Chaetodon meyeri Bloch & J. G. Schneider, 1801 (Scrawled butterflyfish)
• Chaetodon ornatissimus G. Cuvier, 1831 (Ornate butterflyfish)
• Chaetodon reticulatus G. Cuvier, 1831 (Mailed butterflyfish)

Subgenus Corallochaetodon (tentatively placed here)

• Chaetodon austriacus Rüppell, 1836 (Blacktail butterflyfish, exquisite butterflyfish)
• Chaetodon lunulatus Quoy & Gaimard, 1825 (Oval butterflyfish, red-finned butterflyfish)
• Chaetodon melapterus Guichenot, 1863 (Arabian butterflyfish) (tentatively placed here)
• Chaetodon trifasciatus M. Park, 1797 (Melon butterflyfish)

Subgenus Discochaetodon

• Chaetodon aureofasciatus W. J. Macleay, 1878 (Golden butterflyfish)
• Chaetodon octofasciatus Bloch, 1787 (Eightband butterflyfish)
• Chaetodon rainfordi McCulloch, 1923 (Rainford's butterflyfish)
• Chaetodon tricinctus Waite, 1901 (Three-striped butterflyfish) (tentatively placed here)

Subgenus Gonochaetodon (tentatively placed here)

• Chaetodon baronessa G. Cuvier, 1829 (Eastern triangle butterflyfish)
• Chaetodon larvatus G. Cuvier, 1831 (Hooded butterflyfish)
• Chaetodon triangulum G. Cuvier, 1831 (Triangle butterflyfish)

Subgenus Megaprotodon

• Chaetodon trifascialis Quoy & Gaimard, 1825 (Chevron Butterflyfish, Triangulate butterflyfish, V-lined butterflyfish)

Subgenus Tetrachaetodon

• Chaetodon andamanensis Kuiter & Debelius (de), 1999 (Andaman butterflyfish) (tentatively placed here)
• Chaetodon bennetti G. Cuvier, 1831 (Bluelashed butterflyfish)
• Chaetodon plebeius G. Cuvier, 1831 (Blue-blotched butterflyfish)
• Chaetodon speculum G. Cuvier, 1831 (Mirror butterflyfish)
• Chaetodon zanzibarensis Playfair (fr), 1867 (Zanzibar butterflyfish)

Including Aspilurochaetodon, Chaetodontops

• 
  Threadfin butterflyfish
  Chaetodon (Rabdophorus) auriga
• 
  Blackwedged butterflyfish
  Chaetodon (Rabdophorus) falcula
• 
  Blackback butterflyfish
  Chaetodon (Rabdophorus) melannotus
• 
  Lined butterflyfish
  Chaetodon (Rabdophorus) lineolatus
• 
  Redtail butterflyfish
  Chaetodon (Rabdophorus) collare
• 
  Black butterflyfish
  Chaetodon (Rabdophorus) flavirostris
• 
  Bluecheek butterflyfish
  Chaetodon (Rabdophorus) semilarvatus
• 
  Saddle butterflyfish
  Chaetodon (Rabdophorus) ephippium

Most are probably either Chaetodon sensu stricto or C. robustus group.

• Chaetodon assarius Waite, 1905 (West Australian butterflyfish)
• Chaetodon dialeucos Salm & Mee, 1989 (Oman butterflyfish)
• Chaetodon humeralis Günther, 1860
• Chaetodon marleyi Regan, 1921 (Doublesash butterflyfish)
• Chaetodon sanctaehelenae Günther, 1868 (Saint Helena butterflyfish)

Several subgenera have been proposed for splitting out of this group. It is becoming clear how the genus might be split up, with a range^[3][4] of DNA sequence data in large parts agreeing with S.D. Blum's landmark 1988 phylogenetic assessment of osteology.^[5]

Basically, a core group around the type species Chaetodon capistratus would remain in Chaetodon, while maybe four clades would be split off. These could use the names Lepidochaetodon, Megaprotodon and Rabdophorus, and there is one unnamed group containing the three-banded butterflyfish (C. robustus) and its relatives. But the monophyly of the Lepidochaetodon group is not fully established; it is both unclear whether Rhombochaetodon is a lineage distinct from Exornator, and whether Lepidochaetodon is indeed closer to these than to any other Chaetodon, particularly to some lineages otherwise placed in Megaprotodon.^[3]

Prognathodes, for some time contained in Chaetodon, is worthy of recognition as full genus, as is Roa.^[6]

Historically, more distantly related fish were placed in Chaetodon too, for resembling them in details – e.g. the common scat Scatophagus argus, which has a similar shape and size, as well as armored larvae like the Chaetodontidae – or simply because they are colorful, smallish, and unusual-looking – e.g. the quite unrelated paradise fish, as C. chinensis.

The classification proposed in Fessler and Westneat is based on the species of Chaetodon they sampled and these sorted into the following clades:^[3]

• Clade 1
  • Chaetodon robustus
  • Chaetodon hoefleri
• Clade 2
  • Chaetodon kleini
  • Chaetodon unimaculatus
  • Chaetodon fremblii
  • Chaetodon burgessi
  • Chaetodon xanthurus
  • Chaetodon paucifasciatus
  • Chaetodon mertensi
  • Chaetodon quadrimaculatus
  • Chaetodon citrinellus
  • Chaetodon multicinctus
  • Chaetodon punctatofasciatus
  • Chaetodon pelewensis
  • Chaetodon sedentarius
  • Chaetodon dolosus
  • Chaetodon miliaris
  • Chaetodon guentheri
• Clade 3
  • Chaetodon austriacus
  • Chaetodon trifasciatus
  • Chaetodon ornatissimus
  • Chaetodon reticularis
  • Chaetodon meyeri
  • Chaetodon larvatus
  • Chaetodon baronessa
  • Chaetodon trifascialis
  • Chaetodon rainfordi
  • Chaetodon octofasciatus
  • Chaetodon bennetti
  • Chaetodon plebius
  • Chaetodon speculum
  • Chaetodon zanzibarensis
• Clade 4
  • Chaetodon ocellatus
  • Chaetodon capistratus
  • Chaetodon striatus
  • Chaetodon semeion
  • Chaetodon ephippium
  • Chaetodon selene
  • Chaetodon melannotus
  • Chaetodon ocellicaudus
  • Chaetodon rafflesi
  • Chaetodon auriga
  • Chaetodon vagabundus
  • Chaetodon collare
  • Chaetodon adiergastos
  • Chaetodon fasciatus
  • Chaetodon lunula
  • Chaetodon semilarvatus
  • Chaetodon lineolatus
  • Chaetodon oxycephalus
  • Chaetodon falcula
  • Chaetodon ulietensis

The oldest fossils that are usually assigned to Chaetodon date from the late Oligocene, about 25 million years ago. But since it is not easy to distinguish this genus from close relatives, it may be that the Oligocene fossils are actually of other Chaetodontidae. The fossil record of this family is scant indeed, only Chelmon (or some similar genus like Chelmonops or Coradion) being known from Miocene remains. As even crude molecular clocks suggest that the ancestors of the Chaetodon and the Chelmops lineage diverged in the Late Eocene already, nothing more can be said without new fossils being discovered.^[7][8]

• Media related to Chaetodon at Wikimedia Commons
• Data related to Chaetodon at Wikispecies