{{Short description|Genus of fishes}} {{Use dmy dates|date=September 2020}} {{Automatic taxobox | fossil_range = {{fossilrange|Middle Miocene|present|Middle Miocene to present}} | image = Acanthurus leucosternon 01.JPG | image_caption = ''Acanthurus leucosternon'' | image2 = Acanthurus achilles (cropped).jpg | image2_caption = ''Acanthurus achilles'' | taxon = Acanthurus | authority = Forsskål, 1775 | type_species = Acanthurus triostegus | type_species_authority = (Linnaeus, 1758) | subdivision_ranks = Species | subdivision = See text | synonyms = {{collapsible list|bullets = true|title=<small>List</small> | ''Acronurus''<br>{{small|Gronow in Gray 1854}} | ''Aspisurus'' <br>{{small|Lacépède, 1802}} | ''Ctenodon'' <br>{{small|Swainson, 1839}} | ''Harpurina'' <br>{{small|Fowler & Bean, 1929}} | ''Harpurus'' <br>{{small|Johann Reinhold Forster, 1788}} | ''Rhomboteuthis'' <br>{{small|Fowler, 1944}} | ''Rhombotides'' <br>{{small|Bleeker, 1863}} | ''Theutis'' <br>{{small|Bonnaterre, 1788}} | ''Theutys'' <br>{{small|Goüan, 1770}} }} | synonyms_ref = <ref name = CofF/> }}
'''''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.
==Taxonomy== ''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.<ref name = CofF>{{Cof family|family=Acanthuridae|access-date=28 August 2023}}</ref><ref name = CofF2>{{Cof genus|genus=Acanthurus|access-date=28 August 2023}}</ref> ''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''.<ref name = Fricke>{{cite journal |author=Ronald Fricke |year=2008 |title=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) |journal=Stuttgarter Beiträge zur Naturkunde A, Neue Serie. |volume=1 |pages=1–76 |url=https://www.researchgate.net/publication/235686196}}</ref> 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.<ref name = Demirjian>{{cite journal| author=Vahe D. Demirjian | year=2014 |title=''Acanthurus'' Forsskål, 1775 (Osteichthyes, ACANTHURIDAE): proposed conservation by designation of ''Chaetodon sohal'' Forsskål, 1775 as the type species |journal=Bulletin of Zoological Nomenclature |volume=71 |issue=2 |pages=81–83 | doi=10.21805/bzn.v71i2.a7 |url=https://www.biotaxa.org/bzn/article/view/38106/32702}}</ref>
It has been proposed that the genus ''Ctenochaetus'' should be merged with ''Acanthurus'', as ''Acanthurus'' is currently paraphyletic.<ref name="Sorenson">{{cite journal |author1=Laurie Sorenson |author2=Francesco Santini |author3=Giorgio Carnevale |author4=Michael E. Alfaro |year=2013 |title=A multi-locus timetree of surgeonfishes (Acanthuridae, Percomorpha), with revised family taxonomy |journal=Molecular Phylogenetics and Evolution |volume=68 |issue=1 |pages=150–160 |doi=10.1016/j.ympev.2013.03.014 |issn=1055-7903 |pmid=23542000 |bibcode=2013MolPE..68..150S }}</ref><ref name=":0">{{Cite journal |last=F. Cowman |first=Peter |date=2019-02-12 |title=Supplementary material from "The evolution of traits and functions in herbivorous coral reef fishes through space and time" |url=https://rs.figshare.com/collections/Supplementary_material_from_The_evolution_of_traits_and_functions_in_herbivorous_coral_reef_fishes_through_space_and_time_/4397657/1 |journal=Proceedings of the Royal Society |language=en |doi=10.6084/m9.figshare.c.4397657.v1}}</ref> All ''Ctenochaetus'' species are nested within ''Acanthurus'', while ''A. nubilis'' and ''A. pyroferus'' are furthermore nested within ''Ctenochaetus''.<ref name=":0" /> 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.<ref name="Nelson5">{{cite book |title=Fishes of the World |edition=5th |author1=J. S. Nelson |author2=T. C. Grande |author3=M. V. H. Wilson |year=2016 |pages=497–502 |publisher=Wiley |isbn=978-1-118-34233-6}}</ref>
=== Etymology === The genus name ''Acanthurus'' comes from Ancient Greek ἄκανθα (''ákantha''), meaning "spine", and οὐρά (''ourá''), 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.<ref name="ETYFish">{{cite web |name-list-style=amp |date=12 January 2021 |editor2=Kenneth J. Lazara |title=Order ACANTHURIFORMES (part 2): Families EPHIPPIDAE, LEIOGNATHIDAE, SCATOPHAGIDAE, ANTIGONIIDAE, SIGANIDAE, CAPROIDAE, LUVARIDAE, ZANCLIDAE and ACANTHURIDAE |url=https://etyfish.org/acanthuriformes2/ |access-date=10 July 2023 |work=The ETYFish Project Fish Name Etymology Database |publisher=Christopher Scharpf and Kenneth J. Lazara |editor1=Christopher Scharpf}}</ref>
== Evolution == Fossil remains of ''Acanthurus'' are known from the Middle Miocene of the former Paratethys region, including Austria, Croatia, Hungary, and Ukraine. The specimens from Austria and Ukraine are assigned to the extinct species †''Acanthurus haueri.'' Their presence coincides with the Middle Miocene Climatic Optimum, and they likely inhabited coralgal and bryozoan-dominated reefs.<ref name=":1">{{Cite journal |last=Dubikovska |first=Anastasiia |last2=Górka |first2=Marcin |last3=Skyrpan |first3=Mykola |last4=Bienkowska-Wasiluk |first4=Malgorzata |last5=Barkaszi |first5=Zoltán |last6=Kovalchuk |first6=Oleksandr |date=2025-01-02 |title=New data on the early Badenian (Middle Miocene) bony fishes of the Forecarpathian Basin |url=https://www.tandfonline.com/doi/full/10.1080/02724634.2025.2516023 |journal=Journal of Vertebrate Paleontology |language=en |volume=45 |issue=1 |doi=10.1080/02724634.2025.2516023 |issn=0272-4634}}</ref><ref>{{Cite journal |last=Tripalo |first=Kristina |last2=Japundžić |first2=Sanja |last3=Sremac |first3=Jasenka |last4=Bošnjak |first4=Marija |date=2016-04-17 |title=First record of Acanthuridae (surgeonfish) from the Miocene deposits of the Medvednica Mt. |url=https://www.geologia-croatica.hr/index.php/GC/article/view/GC.2016.15 |journal=Geologia Croatica |language=en |volume=69 |issue=2 |pages=201–204 |doi=10.4154/GC.2016.15 |issn=1333-4875}}</ref> Previously, specimens from Monte Bolca in Italy were also assigned to the modern ''Acanthurus'',<ref name="Sepkoski2002">Sepkoski, J.J.Jr (2002): [http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class A Compendium of Fossil Marine Animal Genera.] {{webarchive|url=https://web.archive.org/web/20110723131237/http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class|date=23 July 2011}} ''Bulletins of American Paleontology, 363: 1–560.''</ref> but they have since been split into their own genera.<ref name=":02">{{Cite journal |last1=Carnevale |first1=G. |last2=Bannikov |first2=Alexandre F. |last3=Marramà |first3=G. |last4=Tyler |first4=James C. |last5=Zorzin. |first5=R. |date=2014 |title=The Bolca Fossil-Lagerstätte: A window into the Eocene World. 5. The Pesciara- Monte Postale Fossil-Lagerstätte: 2. Fishes and other vertebrates. Excursion guide |url=https://iris.unito.it/bitstream/2318/149338/1/Carnevale%20et%20al%202014%20The%20Pesciara%20F-L.%20Fishes%20and%20other%20vertebrates2.pdf |journal=Rendiconti della Società Paleontologica Italiana |volume=4 |issue=1 |pages=i–xxvii |hdl=10088/25678}}</ref>
==Distribution== ''Acanthrus'' surgeonfishes are distributed around the world in tropical waters.<ref name="STRI" />
==Species== There are currently 41 recognized species in this genus:<ref name="Fishbase">{{FishBase genus|genus=Acanthurus|month=June|year=2023}}</ref> {{Clear}} {| class="wikitable" |+ !Species !Common name !Image |- |''Acanthurus achilles'' <small>G. Shaw, 1803</small> |Achilles surgeonfish |frameless|200x200px |- |''Acanthurus albimento'' <small>K. E. Carpenter, J. T. Williams & M. D. Santos, 2017</small> |White-chin surgeonfish<ref name="Carpenter2017">Carpenter, K.E., Williams, J.T. & Santos, M.D. (2017): [http://oceansciencefoundation.org/josf/josf25d.pdf ''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.''</ref> | |- |''Acanthurus albipectoralis'' <small>G. R. Allen & Ayling, 1987</small> |White-fin surgeonfish |frameless|200x200px |- |''Acanthurus auranticavus'' <small>J. E. Randall, 1956</small> |Orange-socket surgeonfish | |- |''Acanthurus bahianus'' <small>Castelnau, 1855</small> |Barber surgeonfish |frameless|200x200px |- |''Acanthurus bariene'' <small>Lesson, 1831</small> |Black-spot surgeonfish |frameless|200x200px |- |''Acanthurus blochii'' <small>Valenciennes, 1835</small> |Ring-tail surgeonfish |frameless|200x200px |- |''Acanthurus chirurgus'' <small>(Bloch, 1787)</small> |Doctorfish tang |frameless|200x200px |- |''Acanthurus chronixis'' <small>J. E. Randall, 1960</small> |Chronixis surgeonfish | |- |''Acanthurus coeruleus'' <small>Bloch & J. G. Schneider, 1801</small> |Atlantic blue tang |frameless|200x200px |- |''Acanthurus dussumieri'' <small>Valenciennes, 1835</small> |Eye-stripe surgeonfish |frameless|200x200px |- |''Acanthurus fowleri'' <small>de Beaufort, 1951</small> |Fowler's surgeonfish |frameless|200x200px |- |''Acanthurus gahhm'' <small>(Forsskål, 1775)</small> |Black surgeonfish |frameless|200x200px |- |''Acanthurus grammoptilus'' <small>J. Richardson, 1843</small> |Fine-lined surgeonfish |frameless|200x200px |- |''Acanthurus guttatus'' <small>J. R. Forster, 1801</small> |White-spotted surgeonfish |frameless|200x200px |- |''Acanthurus japonicus'' <small>(P. J. Schmidt, 1931)</small> |Japan surgeonfish |frameless|200x200px |- |''Acanthurus leucocheilus'' <small>Herre, 1927</small> |Pale-lipped surgeonfish |frameless|200x200px |- |''Acanthurus leucopareius'' <small>(O. P. Jenkins, 1903)</small> |White-bar surgeonfish |frameless|200x200px |- |''Acanthurus leucosternon'' <small>E. T. Bennett, 1833</small> |Powder-blue surgeonfish |frameless|200x200px |- |''Acanthurus lineatus'' <small>(Linnaeus, 1758)</small> |Lined surgeonfish |frameless|200x200px |- |''Acanthurus maculiceps'' <small>(C. G. E. Ahl, 1923)</small> |White-freckled surgeonfish |frameless|200x200px |- |''Acanthurus mata'' <small>(G. Cuvier, 1829)</small> |Elongate surgeonfish |frameless|200x200px |- |''Acanthurus monroviae'' <small>Steindachner, 1876</small> |Monrovia surgeonfish |frameless|200x200px |- |''Acanthurus nigricans'' <small>(Linnaeus, 1758)</small> |White-cheek surgeonfish |frameless|200x200px |- |''Acanthurus nigricauda'' <small>Duncker & Mohr (de), 1929</small> |Epaulette surgeonfish |frameless|200x200px |- |''Acanthurus nigrofuscus'' <small>(Forsskål, 1775)</small> |Brown surgeonfish |frameless|200x200px |- |''Acanthurus nigroris'' <small>Valenciennes, 1835</small> |Blue-lined surgeonfish |frameless|200x200px |- |''Acanthurus nigros'' <small>Günther, 1861</small> |Grey-head surgeonfish<ref name="Randall2011">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.''</ref> |frameless|200x200px |- |''Acanthurus nubilus'' <small>(Fowler & B. A. Bean, 1929)</small> |Pin-striped surgeonfish |frameless|200x200px |- |''Acanthurus olivaceus'' <small>Bloch & J. G. Schneider, 1801</small> |Orange-spot surgeonfish |frameless|200x200px |- |''Acanthurus polyzona'' <small>(Bleeker, 1868)</small> |Black-barred surgeonfish |frameless|200x200px |- |''Acanthurus pyroferus'' <small>Kittlitz, 1834</small> |Chocolate surgeonfish |frameless|200x200px |- |''Acanthurus randalli'' <small>J. C. Briggs & D. K. Caldwell, 195</small><small>7</small> | | |- |''Acanthurus reversus'' <small>J. E. Randall & Earle, 199</small><small>9</small> | |frameless|200x200px |- |''Acanthurus sohal'' <small>(Forsskål, 1775)</small> |Sohal surgeonfish |frameless|200x200px |- |''Acanthurus tennentii'' <small>Günther, 1861</small> |Double-band surgeonfish |frameless|200x200px |- |''Acanthurus thompsoni'' <small>(Fowler, 1923)</small> |Thompson's surgeonfish |frameless|200x200px |- |''Acanthurus tractus'' <small>F. Poey, 1860</small> |Ocean surgeonfish<ref name="Bernal2011">Bernal, M.A. & Rocha, L.A. (2011): [http://www.mapress.com/zootaxa/2011/f/zt02905p068.pdf ''Acanthurus tractus'' Poey, 1860, a valid western Atlantic species of surgeonfish (Teleostei, Acanthuridae), distinct from ''Acanthurus bahianus'' Castelnau, 1855.] ''Zootaxa, 2905: 63–68.''</ref> |frameless|200x200px |- |''Acanthurus triostegus'' <small>(Linnaeus, 1758)</small> |Convict surgeonfish |frameless|200x200px |- |''Acanthurus tristis'' <small>J. E. Randall, 1993</small> |Indian Ocean mimic surgeonfish |frameless|200x200px |- |''Acanthurus xanthopterus'' <small>Valenciennes, 1835</small> |Yellow-fin surgeonfish |frameless|200x200px |}
=== Fossil species ===
* †''Acanthurus haueri'' <small>(von Meyer, 1842)</small> (Middle Miocene of Austria and Ukraine)<ref name=":1" />
==Characteristics== {{Multiple image | total_width = 300 | image1 = Acanthurus spine peduncle.jpg | image2 = Acanthurus xanthopterus boca.jpg | footer = ''A. xanthopterus'' tail spine and teeth }} ''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.<ref name="STRI">{{cite web | url = https://biogeodb.stri.si.edu/caribbean/en/thefishes/taxon/2155 | title = Genus: Acanthurus, Common Surgeonfish, Surgeonfishes, Tangs | access-date = 29 August 2023 | work = Shorefishes of the Greater Caribbean online information system | publisher = Smithsonian Tropical Research Institute}}</ref>
The Indo-Pacific yellowfin surgeonfish (''A. xanthopterus'') is the largest species with a maximum published total length of {{cvt|70|cm}} while the smallest is the black-barred surgeonfish (''A. polyzona'') with a maximum published total length of {{cvt|11|cm}}.<ref name="Fishbase" />
==References== {{Commons category}} {{Reflist}}
{{Taxonbar|from=Q648200}} {{Authority control}}
Category:Acanthurus Category:Acanthurini Category:Marine fish genera Category:Taxa named by Peter Forsskål