Acentrophorus

Acentrophorus
Temporal range: Roadian to Wuchiapingian[1] Possible Anisian occurrence
Acentrophorus varians
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Clade: Ginglymodi (?)
Family: Acentrophoridae
Berg, 1936
Genus: Acentrophorus
Traquair, 1877
Type species
Palaeoniscus glaphyrus
Agassiz, 1835
Species

See text

Acentrophorus is an extinct genus of prehistoric freshwater and marine ray-finned fish from the Roadian (Guadalupian/Middle Permian) to the Wuchiapingian (Lopingian/late Permian) of England (Marl Slate), Germany (Kupferschiefer), Italy (Val Gardena) and Russia (Baitugan Formation).[2] There may also be a Triassic occurrence in Australia.[1]

Classification

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The type species, Acentrophorus glaphyrus, was first described under the genus name "Palaeoniscus" (=Palaeoniscum) by Louis Agassiz.[3] Ramsay H. Traquair later erected a new genus for this species, Acentrophorus, to which he also referred the species "Palaeoniscus" abbsii, "P." altus and "P." varians.[4] Some studies suggest that Archaeolepidotus, another very early holostean, may be a junior synonym of this genus.[5]

Acentrophorus is considered to be the oldest known neopterygian,[6] the group of ray-finned fish that encompasses the vast majority of extant species. It is often classified into its own family, Acentrophoridae.[7][8] It is generally referred to the ginglymodian order Semionotiformes.[9] However, the genus has been described as "enigmatic"[10] and "pending restudy".[11]

Species

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The following species are known:[1][7]

  • A. abbsii (Kirkby, 1862) (Late Permian of the United Kingdom)
  • A. altus (Kirkby, 1864) (Late Permian of the United Kingdom)
  • A. glaphyrus (Agassiz, 1833) (syn: A. varians (Kirkby, 1862))[7] (Middle to Late Permian of the United Kingdom, Germany and Russia)[1]
  • A. robustus Brandt, 2021 (Late Permian of Italy)

The former species A. dispersus from the Late Carboniferous of the Czech Republic has been reclassified into Spinarichthys in the Aeduellidae. The former species "A. chicopensis" Newberry, 1888 from the Late Triassic/Early Jurassic Portland Formation of Massachusetts is both significantly younger than other members of the genus and has differing morphology, and it is thus no longer considered to belong to the genus.[7]

See also

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References

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  1. ^ a b c d "PBDB". paleobiodb.org. Retrieved 2024-02-26.
  2. ^ Romano, Carlo; Koot, Martha B.; Kogan, Ilja; Brayard, Arnaud; Minikh, Alla V.; Brinkmann, Winand; Bucher, Hugo; Kriwet, Jürgen (2016). "Permian-Triassic Osteichthyes (bony fishes): diversity dynamics and body size evolution". Biological Reviews. 91 (1): 106–147. doi:10.1111/brv.12161. PMID 25431138. S2CID 5332637.
  3. ^ Agassiz, Louis (1833–1843). Recherches sur les poissons fossiles. Petitpierre, Neuchâtel.
  4. ^ Traquair, Ramsay H. (1877). "On the Agassizian Genera Amblypterus, Palæoniscus, Gyrolepis, and Pygopterus". Quarterly Journal of the Geological Society. 33 (1–4): 548–578. doi:10.1144/GSL.JGS.1877.033.01-04.33. S2CID 128716999.
  5. ^ Tintori, Andrea; Lombardo, Cristina (2007-11-30). "A New Early Semionotidae (Semionotiformes, Actinopterygii) from the Upper Ladinian of Monte San Giorgio Area Southern Switzerland and Northern Italy)". Rivista Italiana di Paleontologia e Stratigrafia. 113 (3). doi:10.13130/2039-4942/5881. ISSN 2039-4942.
  6. ^ "Neopterygii: Semionotiformes". Palaeos. Retrieved 9 March 2017.
  7. ^ a b c d Wachtler, Michael; Wachtler, Nicholas (May 2021). Permian Fossil Floras and Faunas from the Dolomites - Permo-Triassic climate catastrophes as basis for the birth of new life forms. Dolomythos Museum. pp. 137–164.{{cite book}}: CS1 maint: date and year (link)
  8. ^ Tintori, Andrea (2008). "A new semionotid fish (Actinopterygii) from the Upper Triassic of northern Italy". Mesozoic Fishes 4 - Homology and Phylogeny.
  9. ^ Sepkoski, Jack (2002). "A compendium of fossil marine animal genera". Bulletins of American Paleontology. 364: 560. Archived from the original on 2011-07-23. Retrieved 2009-02-23.
  10. ^ Friedman, Matt (2022). "The Macroevolutionary History of Bony Fishes: A Paleontological View". Annual Review of Ecology, Evolution, and Systematics. 53 (1): 353–377. doi:10.1146/annurev-ecolsys-111720-010447. ISSN 1543-592X. S2CID 251888176.
  11. ^ Romano, Carlo (2021). "A Hiatus Obscures the Early Evolution of Modern Lineages of Bony Fishes". Frontiers in Earth Science. 8: 618853. doi:10.3389/feart.2020.618853.