Beardfish
Genus of fishes
From Wikipedia, the free encyclopedia
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 /pɒliˈmɪksi.ɪfɔːrmiːz/.[1] But as Nelson says, "few groups have been shifted back and forth as frequently as this one, and they were recently added to Paracanthoptergii".[2] 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.[3]
| Beardfishes Temporal range: Possible Albian occurrence | |
|---|---|
| |
| Polymixia nobilis | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Clade: | Acanthomorpha |
| Order: | Polymixiiformes Rosen & Patterson, 1969 |
| Type species | |
| Polymixia nobilis R. T. Lowe, 1838 | |
| Families | |
| |
| Synonyms | |
| |
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 800 m (2,600 ft) depth. Most are relatively small fish, although one species, Polymixia berndti, is over 40 cm (16 in) in length.[3]
The earliest body fossils are from the Late Cenomanian of Lebanon, of the genus Pycnosteroides.[4] However, tentative earlier records are known from distinctive fossil otoliths from the Early Cretaceous (Albian) of Texas, USA.[5] 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.[6] Maastrichtian-aged fossils of the genus Elnorichthys indicate that some Cretaceous beardifsh even inhabited freshwater habitats.[7] Extant beardfish can thus be considered "living fossils".[8]
Classification
- Order Polymixiiformes Rosen & Patterson, 1969[6][9][10]
- Genus ?†Allocyclostoma Schwarzhans, Stringer & Welton, 2022 [otolith][5]
- †A. alienus Schwarzhans, Stringer & Welton, 2022
- Genus †Cumbaaichthys Murray 2016
- †Cumbaaichthys oxyrhynchus Murray 2016
- Genus †Severnichthys Stringer & Schwarzhans, 2021 [otolith][11]
- †S. beauryi (Schwarzhans, 2010)
- †S. bourdoni Stringer & Schwarzhans, 2021
- Genus ?†Texoma Schwarzhans, Stringer & Welton, 2022 [otolith][5]
- †T. cyclogaster Schwarzhans, Stringer & Welton, 2022
- Family †Boreiohydriidae Murray & Cumbaa 2013
- Genus †Boreiohydrias Murray & Cumbaa 2013
- †Boreiohydrias dayi Murray & Cumbaa 2013
- Genus †Elnorichthys Murray et al, 2026 (tentatively placed in this family)[7]
- †Elnorichthys pennockae Murray et al, 2026
- Genus †Boreiohydrias Murray & Cumbaa 2013
- Family †Dalmatichthyidae Radovčić 1975
- Genus †Dalmatichthys Radovčić 1975
- †Dalmatichthys malezi Radovčić 1975
- Genus †Dalmatichthys Radovčić 1975
- Family †Digoriidae Bannikov 1985
- Genus †Digoria Daniltshenko, 1980
- †Digoria ambigua Daniltshenko, 1980
- Genus †Digoria Daniltshenko, 1980
- Family †Dinopterygidae Jordan, 1923
- Genus †Dinopteryx Woodward, 1901
- †Dinopteryx spinosus (Davis, 1887)
- Genus †Dinopteryx Woodward, 1901
- 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][12]
- †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][13]
- †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)[8]
- P. fusca Kotthaus 1970
- †?P. harderi (Schwarzhans 2003) [otolith][14]
- 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
Fossil of Polyspinatus
- Genus †Polyspinatus Schrøder, Rasmussen, Møller & Carnevale, 2022[4]
- †Polyspinatus fluere Schrøder, Rasmussen, Møller & Carnevale, 2022
- Genus †Apricenaichthys Taverne 2011
- Family †Pycnosteroididae Patterson, 1964
- Genus †Magrebichthys Murray & Wilson 2014
- †Magrebichthys nelsoni Murray & Wilson 2014
- Genus †Pycnosteroides Woodward, 1942
- †Pycnosteroides levispinosus (Hay, 1903)
- Genus †Magrebichthys Murray & Wilson 2014
- Genus ?†Allocyclostoma Schwarzhans, Stringer & Welton, 2022 [otolith][5]
