Neopterygii (from Greek νέος neos 'new' and πτέρυξ pteryx 'fin') is a subclass of ray-finned fish (Actinopterygii). Neopterygii includes the Holostei and the Teleostei, of which the latter comprise the vast majority of extant fishes, and over half of all living vertebrate species.[2] While living holosteans include only freshwater taxa, teleosts are diverse in both freshwater and marine environments. Many new species of teleosts are scientifically described each year.[2]

Neopterygii
Temporal range: Early Triassic–Present
Siganus corallinus (a teleost)
Lepisosteus oculatus (a holostean)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
(unranked): Actinopteri
Subclass: Neopterygii
Regan, 1923[1]
Infraclasses

For others, see text

The potentially oldest known neopterygian is the putative "semionotiform" Acentrophorus varians from the Middle Permian of Russia;[3][4] however, one study incorporating morphological data from fossils and molecular data from nuclear and mitochondrial DNA, places this divergence date at least 284 mya (million years ago), during the Artinskian stage of the Early Permian.[5] Another study suggests an even earlier split (360 myr ago, near the Devonian-Carboniferous boundary).[6]

Vertebrates

Jawless fishes (118 living species: hagfish, lampreys)

Jawed vertebrates

Cartilaginous fishes (>1,100 living species: sharks, rays, chimaeras)

Bony fishes
Lobe-fins

Actinistia (2 living species: coelacanths)

Rhipidistia

Dipnoi (6 living species: lungfish)

Tetrapoda (>30,000 living species: amphibians, mammals, reptiles, birds)

Ray-fins

Cladistia (14 living species: bichirs, reedfish)

Actinopteri

Chondrostei (27 living species: sturgeons, paddlefish)

Neopterygii (>32,000 living species)

Evolution and diversity

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Living neopterygians are subdivided into two main groups (infraclasses): teleosts and holosteans.[7] Holosteans comprise two clades, the Ginglymodi and the Halecomorphi.[8][2][9][10] All of these groups have a long and extensive fossil record.[11] The evolutionary relationships between the different groups of Neopterygii is summarized in the cladogram below (divergence time for each clade in mya are based on[12]).

Neopterygii 360 mya
Holostei 275 mya

Ginglymodi   (7 living species: gars and alligator gars)

Halecomorphi   (2 living species: bowfin and eyespot bowfin)

310 mya

Teleostei   (>32,000 living species)

Neopterygians are a very speciose group. They make up over 50% of the total vertebrate diversity today, and their diversity grew since the Mesozoic era.[11][13] However, the diversity of the various groups of neopterygians (or of fishes in general) is unevenly distributed, with teleosts making up the vast majority (96%) of living species.[2]

 
Early Triassic parasemionotiform Watsonulus is an early neopterygian.

Early in their evolution, neopterygians were a very successful group of fish, because they could move more rapidly than their ancestors. Their scales and skeletons began to lighten during their evolution, and their jaws became more powerful and efficient.[2] While electroreception and the ampullae of Lorenzini are present in all other extant groups of fish (except for hagfish), neopterygians have lost this sense, even if it has later re-evolved within Gymnotiformes and catfishes, which possess non-homologous teleost ampullae.[14]

Only a few changes occurred during the evolution of neopterygians from the earlier actinopterygians. However, a very important step in the evolution of neopterygians is the acquisition of a better control of the movements of both dorsal and anal fins, resulting in an improvement in their swimming capabilities. They additionally acquired several modifications in the skull, which allowed the evolution of different feeding mechanisms and consequently the colonization of new ecological niches. All of these characters represented major improvements, resulting in Neopterygii becoming the dominant group of fishes (and, thus, taxonomically of vertebrates in general) today.[11]

The great diversity of extant teleosts has been linked to a whole genome duplication event during their evolution.[15]

Classification

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References

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  1. ^ Regan, C. Tate (1923). "The Skeleton of Lepidosteus, with remarks on the origin and evolution of the lower Neopterygian Fishes". Journal of Zoology. 93 (2): 445–461. doi:10.1111/j.1096-3642.1923.tb02191.x.
  2. ^ a b c d e Nelson, Joseph, S. (2016). Fishes of the World. John Wiley & Sons, Inc. ISBN 978-1-118-34233-6.{{cite book}}: CS1 maint: multiple names: authors list (link)
  3. ^ Broughton, Richard E.; Betancur-R., Ricardo; Li, Chenhong; Arratia, Gloria; Ortí, Guillermo (2013-04-16). "Multi-locus phylogenetic analysis reveals the pattern and tempo of bony fish evolution". PLOS Currents. 5: ecurrents.tol.2ca8041495ffafd0c92756e75247483e. doi:10.1371/currents.tol.2ca8041495ffafd0c92756e75247483e (inactive 1 November 2024). ISSN 2157-3999. PMC 3682800. PMID 23788273.{{cite journal}}: CS1 maint: DOI inactive as of November 2024 (link)
  4. ^ "PBDB". paleobiodb.org. Retrieved 2024-02-26.
  5. ^ Hurley, Imogen A.; Mueller, Rachael Lockridge; Dunn, Katherine A. (21 November 2006). "A new time-scale for ray-finned fish evolution". Proceedings of the Royal Society B. 274 (1609): 489–498. doi:10.1098/rspb.2006.3749. PMC 1766393. PMID 17476768.
  6. ^ Thomas J. Near; et al. (2012). "Resolution of ray-finned fish phylogeny and timing of diversification". PNAS. 109 (34): 13698–13703. Bibcode:2012PNAS..10913698N. doi:10.1073/pnas.1206625109. PMC 3427055. PMID 22869754.
  7. ^ López-Arbarello, A (2012). "Phylogenetic Interrelationships of Ginglymodian Fishes (Actinopterygii: Neopterygii)". PLOS ONE. 7 (7): e39370. Bibcode:2012PLoSO...739370L. doi:10.1371/journal.pone.0039370. PMC 3394768. PMID 22808031.
  8. ^ Betancur-R (2016). "Phylogenetic Classification of Bony Fishes Version 4".
  9. ^ "Actinopterygii". Integrated Taxonomic Information System. Retrieved 3 April 2006.
  10. ^ R. Froese and D. Pauly, ed. (February 2006). "FishBase".
  11. ^ a b c Friedman, Matt; Sallan, Lauren Cole (June 2012). "Five hundred million years of extinczion and recovery: A Phanerozoic survey of large-scale diversity patterns in fishes". Palaeontology. 55 (4): 707–742. Bibcode:2012Palgy..55..707F. doi:10.1111/j.1475-4983.2012.01165.x. S2CID 59423401.
  12. ^ Thomas J. Near; et al. (2012). "Resolution of ray-finned fish phylogeny and timing of diversification". PNAS. 109 (34): 13698–13703. Bibcode:2012PNAS..10913698N. doi:10.1073/pnas.1206625109. PMC 3427055. PMID 22869754.
  13. ^ Romano, Carlo; Koot, Martha B.; Kogan, Ilja; Brayard, Arnaud; Minikh, Alla V.; Brinkmann, Winand; Bucher, Hugo; Kriwet, Jürgen (February 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.
  14. ^ Electroreception By Theodore Holmes Bullock
  15. ^ Pasquier, Jeremy; Braasch, Ingo; Batzel, Peter; Cabau, Cedric; Montfort, Jérome; Nguyen, Thaovi; Jouanno, Elodie; Berthelot, Camille; Klopp, Christophe; Journot, Laurent; Postlethwai, John H.; Guigue, Yann; Bob, Julien (2017). "Evolution of gene expression after whole-genome duplication: new insights from the spotted gar genome". J Exp Zool (Mol Dev Evol). 328 (7): 709–721. Bibcode:2017JEZB..328..709P. doi:10.1002/jez.b.22770. PMC 5679426. PMID 28944589.
  16. ^ Xu, Guang-Hui (2021-01-09). "A new stem-neopterygian fish from the Middle Triassic (Anisian) of Yunnan, China, with a reassessment of the relationships of early neopterygian clades". Zoological Journal of the Linnean Society. 191 (2): 375–394. doi:10.1093/zoolinnean/zlaa053. ISSN 0024-4082.
  17. ^ In ITIS, Gobiesociformes is placed as the suborder Gobiesocoidei of the order Perciformes.
  18. ^ In ITIS, Syngnathiformes is placed as the suborder Syngnathoidei of the order Gasterosteiformes.