Genus of fishes
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 .[ 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]
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] Extant beardfish can thus be considered "living fossils ".[ 7]
Classification
Order Polymixiiformes Rosen & Patterson, 1969 [ 6] [ 8] [ 9]
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][ 10]
†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
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][ 11]
†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][ 12]
†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 ]
Genus †Polyspinatus Schrøder, Rasmussen, Møller & Carnevale, 2022 [ 4]
†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)
Timeline of genera
References
^ Froese, Rainer ; Pauly, Daniel (eds.). "Order Polymixiiformes" . FishBase . February 2006 version.
^ Joseph S. Nelson (29 April 1994). Fishes of the World . John Wiley & Sons. ISBN 0-471-54713-1 .
^ a b Paxton, John R. (1998). Paxton, J.R.; Eschmeyer, W.N. (eds.). Encyclopedia of Fishes . San Diego: Academic Press. p. 161. ISBN 0-12-547665-5 .
^ a b Schrøder, Ane Elise; Rasmussen, Jan Audun; Møller, Peter Rask; Carnevale, Giorgio (2022-08-31). "A new beardfish (Teleostei, Polymixiiformes) from the Eocene Fur Formation, Denmark" . Journal of Vertebrate Paleontology . 42 (2). doi :10.1080/02724634.2022.2142914 . hdl :10037/28645 . ISSN 0272-4634 .
^ a b c Schwarzhans, Werner; Stringer, Gary L.; Welton, Bruce (2022-12-01). "Oldest Teleostean Otolith Assemblage from North America (Pawpaw Formation, Lower Cretaceous, upper Albian, northeast Texas, USA)" . Cretaceous Research . 140 : 105307. doi :10.1016/j.cretres.2022.105307 . ISSN 0195-6671 .
^ a b Murray, Alison M. (2014). "Mid-Cretaceous acanthomorph fishes with the description of a new species from the Turonian of Lac des Bois, Northwest Territories, Canada" . Vertebrate Anatomy Morphology Palaeontology . 1 : 101–115. doi :10.18435/B5CC78 . ISSN 2292-1389 .
^ a b De Cia Caixeta, Heloísa; Oliveira, Claudio; Melo, Marcelo Roberto Souto de (2024-03-01). "Another piece of the living fossil puzzle: A new species of Polymixia Lowe, 1836 (Polymixiiformes: Polymixiidae) from the western South Atlantic" . Deep Sea Research Part I: Oceanographic Research Papers . 205 : 104249. doi :10.1016/j.dsr.2024.104249 . ISSN 0967-0637 .
^ Haaramo, Mikko (2007). "Polymixiomorpha – beardfishes and relatives " . Mikko's Phylogeny Archive . Retrieved 30 December 2016 .
^ "Part 7- Vertebrates" . Collection of genus-group names in a systematic arrangement . Archived from the original on 2016-10-05. Retrieved 30 June 2016 .
^ Stringer, Gary; Schwarzhans, Werner (2021). "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" . Cretaceous Research . 125 : 104867. doi :10.1016/j.cretres.2021.104867 . ISSN 0195-6671 .
^ SCHWARZHANS, WERNER W.; HUDDLESTON, RICHARD W.; TAKEUCHI, GARY T. (2018-01-22). "A LATE SANTONIAN FISH-FAUNA FROM THE EUTAW FORMATION OF ALABAMA RECONSTRUCTED FROM OTOLITHS" . Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy) . V. 124: N. 1 (2018). doi :10.13130/2039-4942/9624 .
^ Schwarzhans, Werner; Ohe, Fumio; Ando, Yusuke (2017). "An Early Oligocene fish-fauna from Japan reconstructed from otoliths" . Zitteliana : 3–26. doi :10.5282/ubm/epub.40475 . ISSN 0373-9627 .
^ "Bulletin Volume 65 – 2017" . Dansk Geologisk Forening (in Danish). 2017-02-15. doi :10.37570/bgsd-2017-65-05 . Retrieved 2024-07-28 .
Polymixiidae Polymixiiformes