Beardfish

{{Short description|Genus of fishes}} {{for|the Swedish band|Beardfish (band)}} {{Automatic taxobox | name = Beardfishes | fossil_range = {{fossil range|95|0|earliest=105|Late Cenomanian to present}} Possible Albian occurrence | image = Polymixia nobilis.jpg | image_caption = ''Polymixia nobilis'' | taxon = Polymixiiformes | authority = Rosen & Patterson, 1969 | subdivision_ranks = Families | subdivision = * †Boreiohydriidae Murray & Cumbaa 2013 * †Dalmatichthyidae Radovčić 1975 * †Digoriidae Bannikov 1985 * †Dinopterygidae Jordan, 1923 * '''Polymixiidae''' Bleeker, 1859 * †Pycnosteroididae Patterson, 1964 | synonyms = * Polymixioidei Bleeker 1859 | type_species = ''Polymixia nobilis'' | type_species_authority = R. T. Lowe, 1838 }}

The '''beardfishes''' consist of a single extant genus, ''Polymixia'', of deep-sea marine ray-finned fish named for their pair of long hyoid barbels. They are classified in their own order '''Polymixiiformes''' {{IPAc-en|p|ɒ|l|i|ˈ|m|ɪ|k|s|i|.||ᵻ|f|ɔːr|m|iː|z}}.<ref name="FB">{{FishBase order | order = Polymixiiformes | month = February | year = 2006}}</ref> But as Nelson says, "few groups have been shifted back and forth as frequently as this one, and they were recently added to Paracanthoptergii".<ref>{{cite book | author = Joseph S. Nelson | title = Fishes of the World | date = 29 April 1994 | publisher = John Wiley & Sons | isbn = 0-471-54713-1}}</ref> For instance, they have previously been classified as belonging to the Beryciformes, and are presently considered either paracanthopterygians or the sister group to acanthopterygians. They are of little economic importance.<ref name=EoF>{{cite book |editor1=Paxton, J.R. |editor2=Eschmeyer, W.N. |author= Paxton, John R.|year=1998|title=Encyclopedia of Fishes|publisher= Academic Press|location=San Diego|page=161|isbn= 0-12-547665-5}}</ref>

They are found in tropical and subtropical waters of the Atlantic, Indian and western Pacific Ocean. They are bottom-dwelling fish, found down to about {{convert|800|m|ft|abbr=on}} depth. Most are relatively small fish, although one species, ''Polymixia berndti'', is over {{convert|40|cm|in|abbr=on}} in length.<ref name=EoF/>

The earliest body fossils are from the Late Cenomanian of Lebanon, of the genus ''Pycnosteroides''.<ref name=":0">{{Cite journal |last=Schrøder |first=Ane Elise |last2=Rasmussen |first2=Jan Audun |last3=Møller |first3=Peter Rask |last4=Carnevale |first4=Giorgio |date=2022-08-31 |title=A new beardfish (Teleostei, Polymixiiformes) from the Eocene Fur Formation, Denmark |url=https://www.tandfonline.com/doi/full/10.1080/02724634.2022.2142914 |journal=Journal of Vertebrate Paleontology |language=en |volume=42 |issue=2 |doi=10.1080/02724634.2022.2142914 |issn=0272-4634|hdl=10037/28645 |hdl-access=free }}</ref> However, tentative earlier records are known from distinctive fossil otoliths from the Early Cretaceous (Albian) of Texas, USA.<ref name=":2">{{Cite journal |last=Schwarzhans |first=Werner |last2=Stringer |first2=Gary L. |last3=Welton |first3=Bruce |date=2022-12-01 |title=Oldest Teleostean Otolith Assemblage from North America (Pawpaw Formation, Lower Cretaceous, upper Albian, northeast Texas, USA) |url=https://www.sciencedirect.com/science/article/pii/S0195667122001719 |journal=Cretaceous Research |volume=140 |article-number=105307 |doi=10.1016/j.cretres.2022.105307 |issn=0195-6671|doi-access=free }}</ref> Many different fossil families and genera are known from the Late Cretaceous and early Cenozoic, in contrast to the relatively few surviving species in a single genus.<ref name=":1">{{Cite journal |last=Murray |first=Alison M. |date=2014 |title=Mid-Cretaceous acanthomorph fishes with the description of a new species from the Turonian of Lac des Bois, Northwest Territories, Canada |url=https://journals.library.ualberta.ca/vamp/index.php/VAMP/article/view/25439 |journal=Vertebrate Anatomy Morphology Palaeontology |language=en |volume=1 |pages=101–115 |doi=10.18435/B5CC78 |issn=2292-1389|doi-access=free }}</ref> Extant beardfish can thus be considered "living fossils".<ref name="auto">{{Cite journal |last=De Cia Caixeta |first=Heloísa |last2=Oliveira |first2=Claudio |last3=Melo |first3=Marcelo Roberto Souto de |date=2024-03-01 |title=Another piece of the living fossil puzzle: A new species of Polymixia Lowe, 1836 (Polymixiiformes: Polymixiidae) from the western South Atlantic |url=https://www.sciencedirect.com/science/article/pii/S0967063724000190 |journal=Deep Sea Research Part I: Oceanographic Research Papers |volume=205 |article-number=104249 |doi=10.1016/j.dsr.2024.104249 |issn=0967-0637}}</ref>

==Classification== * '''Order Polymixiiformes''' Rosen & Patterson, 1969<ref name=":1" /><ref name="mikko">{{cite web|website=Mikko's Phylogeny Archive|last=Haaramo|first=Mikko|year=2007|title=''Polymixiomorpha – beardfishes and relatives'' |url=http://www.helsinki.fi/~mhaaramo/metazoa/deuterostoma/chordata/actinopterygii/polymixiomorpha.html#Ctenothrissiformes |access-date= 30 December 2016}}</ref><ref>{{cite journal| website=Collection of genus-group names in a systematic arrangement| title=Part 7- Vertebrates| url=http://mave.tweakdsl.nl/tn/genera7.html| display-authors=etal| access-date=30 June 2016| archive-url=https://web.archive.org/web/20161005114629/http://mave.tweakdsl.nl/tn/genera7.html| archive-date=2016-10-05}}</ref> ** Genus ?†''Allocyclostoma'' Schwarzhans, Stringer & Welton, 2022 <nowiki/>[<nowiki/>otolith]<ref name=":2" /> ***†''A. alienus'' Schwarzhans, Stringer & Welton, 2022 ** Genus †''Cumbaaichthys'' Murray 2016 *** †''Cumbaaichthys oxyrhynchus'' Murray 2016 **Genus †''Severnichthys'' Stringer & Schwarzhans, 2021 [<nowiki/>otolith]<ref>{{Cite journal |last=Stringer |first=Gary |last2=Schwarzhans |first2=Werner |date=2021 |title=Upper Cretaceous teleostean otoliths from the Severn Formation (Maastrichtian) of Maryland, USA, with an unusual occurrence of Siluriformes and Beryciformes and the oldest Atlantic coast Gadiformes |journal=Cretaceous Research |volume=125 |article-number=104867 |doi=10.1016/j.cretres.2021.104867 |issn=0195-6671|doi-access=free }}</ref> ***†''S. beauryi'' (Schwarzhans, 2010) ***†''S. bourdoni'' Stringer & Schwarzhans, 2021 **Genus ?†''Texoma'' Schwarzhans, Stringer & Welton, 2022 [otolith]<ref name=":2" /> ***†''T. cyclogaster'' Schwarzhans, Stringer & Welton, 2022 ** '''Family''' †'''Boreiohydriidae''' Murray & Cumbaa 2013 *** Genus †''Boreiohydrias'' Murray & Cumbaa 2013 **** †''Boreiohydrias dayi'' Murray & Cumbaa 2013 ** '''Family''' †'''Dalmatichthyidae''' Radovčić 1975 *** Genus †''Dalmatichthys'' Radovčić 1975 **** †''Dalmatichthys malezi'' Radovčić 1975 ** '''Family''' †'''Digoriidae''' Bannikov 1985 *** Genus †''Digoria'' Daniltshenko, 1980 **** †''Digoria ambigua'' Daniltshenko, 1980 ** Family †'''Dinopterygidae''' Jordan, 1923 *** Genus †''Dinopteryx'' Woodward, 1901 **** †''Dinopteryx spinosus'' (Davis, 1887) ** '''Family Polymixiidae''' Gill 1862 [Berycopsidae Regan 1911; Dalmatichthyidae Radovčić 1975; Omosomopsidae Gaudant 1978; Homonotichthyidae Whitley 1933] *** Genus †''Apricenaichthys'' Taverne 2011 **** †''Apricenaichthys italicus'' *** Genus †''Berycopsia'' Radovčić 1975 **** †''Berycopsia inopinnata'' Radovčić 1975 *** Genus †''Berycopsis'' Dixon 1850 [''Platycormus'' von der Marck 1900] **** †''B. elegans'' Dixon 1850 [''Platycormus elegans'' (Dixon 1850)] **** †''B. germana'' (Agassiz 1839) [''Beryx germanus'' Agassiz 1839; ''Platycormus germanus'' (Agassiz 1839)] **** †''B. pulcher'' Bannikov & Bacchia 2004 ***Genus †''Cowetaichthys'' Schwarzhans, Huddleston & Takeuchi, 2018 [otolith]<ref>{{Cite journal |last=SCHWARZHANS |first=WERNER W. |last2=HUDDLESTON |first2=RICHARD W. |last3=TAKEUCHI |first3=GARY T. |date=2018-01-22 |title=A LATE SANTONIAN FISH-FAUNA FROM THE EUTAW FORMATION OF ALABAMA RECONSTRUCTED FROM OTOLITHS |url=https://riviste.unimi.it/index.php/RIPS/article/view/9624 |journal=Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy) |language=en |volume=V. 124 |pages=N. 1 (2018) |doi=10.13130/2039-4942/9624}}</ref> ****†''C. alabamae'' Schwarzhans, Huddleston & Takeuchi, 2018 ****†''C. beauryi'' (Schwarzhans, 2010) ****†''C. carnevalei'' Schwarzhans & Stringer, 2020 ****†''C. groenlandicus'' (Schwarzhans, 2004) ****†''C. harderi'' (Schwarzhans, 2003) ****†''C. lamberi'' Schwarzhans, Huddleston & Takeuchi, 2018 *** Genus †''Homonotichthys'' Whitley 1933 **** †''H. dorsalis'' (Dixon 1850) [''Homonotus dorsalis'' Dixon 1850] **** †''H. elegans'' (Dixon 1850) [''Homonotus elegans'' Dixon 1850] **** †''H. rotundus'' (Woodward 1902) [''Homonotus rotundus'' Woodward 1902] ***Genus †''Namicauda'' Schwarzhans, Ohe & Ando, 2017 [otolith]<ref>{{Cite journal |last=Schwarzhans |first=Werner |last2=Ohe |first2=Fumio |last3=Ando |first3=Yusuke |date=2017 |title=An Early Oligocene fish-fauna from Japan reconstructed from otoliths |url=https://epub.ub.uni-muenchen.de/40475/ |journal=Zitteliana |pages=3–26 |doi=10.5282/ubm/epub.40475 |issn=0373-9627}}</ref> ****†''Namicauda pulvinata'' Schwarzhans, Ohe & Ando, 2017 *** Genus †''Omosoma'' Costa 1857 **** †''O. garretti'' Bardack 1976 **** †''O. pulchellum'' Davis 1887 **** †''O. sahelalmae'' Costa 1857 **** †''O. tselfatense'' Gaudant 1978 *** Genus †''Omosomopsis'' Gaudant 1978 **** †''Omosomopsis sima'' (Arambourg 1954) Gaudant 1978 *** Genus †''Parapolymixia'' David 1946 **** †''Parapolymixia californica'' David 1946 *** Genus †''Pycnosterinx'' Heckel 1849 [''Imogaster'' Costa 1857] **** †''P. discoides'' Heckel 1849 **** †''P. dorsalis'' Pictet 1850 **** †''P. heckelii'' Pictet 1850 **** †''P. latus'' Davis 1887 **** †''P. russeggeri'' Heckel 1849 [''Homonotus pulcher'' Davis 1886] *** Genus ''Polymixia'' Lowe 1836 [''Dinemus'' Poey 1860; ''Nemobrama'' Valenciennes 1860 non Jordan, Evermann & Clark 1930] **** ''P. berndti'' Gilbert 1905 (Pacific beardfish) **** ''P. busakhini'' Kotlyar 1993 (Busakhin's beardfish) **** ''P. carmenae'' Caixeta, Oliveira & de Melo, 2024 (Brazilian beardfish)<ref name="auto"/> **** ''P. fusca'' Kotthaus 1970 **** †?''P. harderi'' (Schwarzhans 2003) [otolith]<ref>{{Cite web |date=2017-02-15 |title=Bulletin Volume 65 – 2017 |url=https://2dgf.dk/publikationer/bulletin/bulletin-volume-65-2017/ |access-date=2024-07-28 |website=Dansk Geologisk Forening |language=da-DK |doi=10.37570/bgsd-2017-65-05}}</ref> **** ''P. hollisterae'' Grande & Wilson, 2021 (Bermuda beardfish) **** ''P. japonica'' Günther 1877 (Silver eye) **** ''P. longispina'' Deng, Xiong & Zhan 1983 [''Polymixia kawadae'' Okamura & Ema 1985] **** ''P. lowei'' Günther 1859 (Beardfish) **** ''P. nobilis'' Lowe 1838 [''Nemobrama webbii'' Valenciennes 1837; ''Dinemus venustus'' Poey 1860; ''Polymixia nobilis virginica'' Nichols & Firth 1936] (Stout beardfish) **** †''P. polita'' Schwarzhans 2012 [otolith] **** ''P. salagomeziensis'' Kotlyar 1991 **** ''P. sazonovi'' Kotlyar 1992 **** ''P. yuri'' Kotlyar 1982[[File:Eocene fish from the Fur Formation.jpg|thumb|Fossil of ''Polyspinatus'']] ***Genus †''Polyspinatus'' Schrøder, Rasmussen, Møller & Carnevale, 2022<ref name=":0" /> ****†''Polyspinatus fluere'' Schrøder, Rasmussen, Møller & Carnevale, 2022 **Family †'''Pycnosteroididae''' Patterson, 1964 ***Genus †''Magrebichthys'' Murray & Wilson 2014 **** †''Magrebichthys nelsoni'' Murray & Wilson 2014 ***Genus †''Pycnosteroides'' Woodward, 1942 ****†''Pycnosteroides levispinosus'' (Hay, 1903)

==References== {{Reflist}} * {{cite journal|last=Sepkoski |first=Jack |title=A compendium of fossil marine animal genera |journal=Bulletins of American Paleontology |volume=364 |page=560 |year=2002 |url=http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class |access-date=2011-05-17 |archive-url=https://web.archive.org/web/20110723131237/http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=611&rank=class |archive-date=2011-07-23 }}

Category:Polymixiiformes Category:Fish of Hawaii Category:Extant Cenomanian first appearances