Acanthurus is a genus of marine ray-finned fish belonging to the family Acanthuridae, which includes the surgeonfishes, unicornfishes and tangs, found in the Atlantic, Indian and Pacific Ocean. They are found in tropical oceans, especially near coral reefs, with most species in the Indo-Pacific but a few are found in the Atlantic Ocean. As other members of the family, they have a pair of spines, one on either side of the base of the tail which are dangerously sharp.

Acanthurus
Temporal range: 55–0 Ma
Early Eocene to Present[1]
Acanthurus leucosternon
Acanthurus achilles
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Acanthuriformes
Family: Acanthuridae
Tribe: Acanthurini
Genus: Acanthurus
Forsskål, 1775
Type species
Teuthis hepatus or Chaetodon sohal
Linnaeus, 1758[2] or Forsskål, 1775[3]
Species

See text

Synonyms[2]
List

Taxonomy

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Acanthurus was first proposed as a subgenus of Chaetodon in 1775 by the Swedish-speaking Finnish explorer, orientalist and naturalist Peter Forsskål, although he recognised that it was probably different from Chaetodon even at the family level. In 1856 Desmarest designated Teuthis hepatus, which had been described from a type now known to have been collected at Ambon Island in the Moluccas (other erroneous type localities were named) in 1758 by Linnaeus, as the type species of the genus.[2][4] T. hepatus is a synonym of Paracanthurus hepatus and this would make Paracanthurus synonymous with Acanthurus. An alternative would be to use the name Harpurus proposed as a monospecific genus in 1788 by Johann Reinhold Forster when he described Harpurus fasciatus, a synonym of Acanthurus triostegus. It has been proposed that the International Commission on Zoological Nomenclature should be petitioned to stabilise the genera Acanthurus and Paracanthurus.[5] In 2014 it was proposed that the type species of Acanthurus should be Chaetodon sohal, which had also been described by Forsskål in 1775 as a member of the subgenus alongside C. bifasciatus, C. nigrofuscus and C. unicornis, and had been designated as the type species by Jordan and Evermann in 1917.[3]

It has been proposed that the genus Ctenochaetus should be merged with Acanthurus as otherwise Acanthurus is paraphyletic.[6] The 5th edition of Fishes of the World recognises these two genera as valid and classifies them as the two genera in the tribe Acanthurini of the subfamily Acanthurinae within the family Acanthuridae.[7]

Etymology

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Acanthurus is a combination of acanthus meaning "spine" and urus meaning "tail", a reference to the scalpel like bony plates on the caudal peduncle, these also give rise to the vernacular English names surgeonfish and doctorfish.[8]

Species

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There are currently 41 recognized species in this genus:[9]

 
A. japonicus
 
A. polyzona
 
A. lineatus

Characteristics

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A. xanthopterus tail spine

Acanthurus surgeonfishes have disc shaped, highly laterally compressed bodies with a steep dorsal profile to the head. They have a small mouth positioned low on the head and the fish can protrude the jaws. The 8 to 28 teeth in the jaws are fixed and have flattened, serrated tips. There are typically 11 spines in the dorsal fin. There is a single spine on each side of the caudal peduncle and these can be pressed down into a groove.[13]

The Indo-Pacific yellowfin surgeonfish (A. xanthopterus) is the largest species with a maximum published total length of 70 cm (28 in) while the smallest is the black-barred surgeonfish (A. polyzona) with a maximum published total length of 11 cm (4.3 in).[9]

Distribution

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Acanthrus surgeonfishes are distributed around the world in tropical waters.[13]

References

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  1. ^ Sepkoski, J.J.Jr (2002): A Compendium of Fossil Marine Animal Genera. Archived 23 July 2011 at the Wayback Machine Bulletins of American Paleontology, 363: 1–560.
  2. ^ a b c Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Genera in the family Acanthuridae". Catalog of Fishes. California Academy of Sciences. Retrieved 28 August 2023.
  3. ^ a b Vahe D. Demirjian (2014). "Acanthurus Forsskål, 1775 (Osteichthyes, ACANTHURIDAE): proposed conservation by designation of Chaetodon sohal Forsskål, 1775 as the type species". Bulletin of Zoological Nomenclature. 71 (2): 81–83.
  4. ^ Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Species in the genus Acanthurus". Catalog of Fishes. California Academy of Sciences. Retrieved 28 August 2023.
  5. ^ Ronald Fricke (2008). "Authorship, availability and validity of fish names described by Peter (Pehr) Simon Forsskål and Johann Christian Fabricius in the 'Descriptiones animalium' by Carsten Niebuhr in 1775 (Pisces)". Stuttgarter Beiträge zur Naturkunde A, Neue Serie. 1: 1–76.
  6. ^ Laurie Sorenson; Francesco Santini; Giorgio Carnevale; Michael E. Alfaro (2013). "A multi-locus timetree of surgeonfishes (Acanthuridae, Percomorpha), with revised family taxonomy". Molecular Phylogenetics and Evolution. 68 (1): 150–160. doi:10.1016/j.ympev.2013.03.014. ISSN 1055-7903.
  7. ^ J. S. Nelson; T. C. Grande; M. V. H. Wilson (2016). Fishes of the World (5th ed.). Wiley. pp. 497–502. ISBN 978-1-118-34233-6.
  8. ^ Christopher Scharpf & Kenneth J. Lazara, eds. (12 January 2021). "Order ACANTHURIFORMES (part 2): Families EPHIPPIDAE, LEIOGNATHIDAE, SCATOPHAGIDAE, ANTIGONIIDAE, SIGANIDAE, CAPROIDAE, LUVARIDAE, ZANCLIDAE and ACANTHURIDAE". The ETYFish Project Fish Name Etymology Database. Christopher Scharpf and Kenneth J. Lazara. Retrieved 10 July 2023.
  9. ^ a b Froese, Rainer; Pauly, Daniel (eds.). "Species in genus Acanthurus". FishBase. June 2023 version.
  10. ^ Carpenter, K.E., Williams, J.T. & Santos, M.D. (2017): Acanthurus albimento, a new species of surgeonfish (Acanthuriformes: Acanthuridae) from northeastern Luzon, Philippines, with comments on zoogeography. Journal of the Ocean Science Foundation, 25: 33–46.
  11. ^ Randall, J.E., DiBattista, J.D. & Wilcox, C. (2011): Acanthurus nigros Günther, a Valid Species of Surgeonfish, Distinct from the Hawaiian A. nigroris Valenciennes. Pacific Science, 65 (2): 265–275.
  12. ^ Bernal, M.A. & Rocha, L.A. (2011): Acanthurus tractus Poey, 1860, a valid western Atlantic species of surgeonfish (Teleostei, Acanthuridae), distinct from Acanthurus bahianus Castelnau, 1855. Zootaxa, 2905: 63–68.
  13. ^ a b "Genus: Acanthurus, Common Surgeonfish, Surgeonfishes, Tangs". Shorefishes of the Greater Caribbean online information system. Smithsonian Tropical Research Institute. Retrieved 29 August 2023.