Editing Characiformes (section)

==Evolution==
The Characiformes likely first originated and diversified on the supercontinent of [[Gondwana|West Gondwana]] (composed of modern Africa and South America) during the Cretaceous period, though fossils are poorly known.<ref name="nelson" /> During the Cretaceous Period, the rift between South America and Africa would be forming; this may explain the contrast in diversity between the two continents. Their low diversity in Africa may explain why some primitive fish families and the Cypriniformes coexist with them whereas they are absent in South America, where these fish may have been driven extinct.<ref name="briggs" /> The characiforms had not spread into Africa soon enough to also reach the land connection between Africa and Asia.<ref name="briggs" /> The earliest they could have spread into Central America was the late [[Miocene]].<ref name="briggs" />

=== Fossils ===
[[File:Lignobrycon ligniticus (P9012).tif|left|thumb|''[[Lignobrycon ligniticus]]'', a fossil characiform from the [[Oligocene]] of Brazil]]
The earliest characiform fossils date back to the Late Cretaceous, around the [[Santonian]].<ref>{{Cite journal |last1=Szabó |first1=Márton |last2=Ősi |first2=Attila |date=2017-09-01 |title=The continental fish fauna of the Late Cretaceous (Santonian) Iharkút locality (Bakony Mountains, Hungary) |url=https://akjournals.com/view/journals/24/60/2/article-p230.xml |journal=Central European Geology |language=en-US |volume=60 |issue=2 |pages=230–287 |doi=10.1556/24.60.2017.009 |bibcode=2017CEJGl..60..230S |issn=1789-3348|hdl=10831/67493 |hdl-access=free }}</ref> Other fossil teeth date back to the [[Cenomanian]] of [[Morocco]], but it has been suggested that these teeth may be of early [[Ginglymodi|ginglymodians]].<ref name=":0" /> Previously, the oldest characiform was assumed to be ''[[Santanichthys]]'' of the Early [[Cretaceous]] ([[Albian]] Age) of [[Brazil]]. This presumably marine taxon was used as evidence of characiformes potentially having marine origins.<ref name="Filleul2004">{{cite journal |last=Filleul |first=Arnaud |author2=John G. Maisey |date=2004-10-28 |title=Redescription of ''Santanichthys diasii'' (Otophysi, Characiformes) from the Albian of the Santana Formation and comments on its implications for Otophysan relationships |url=https://zenodo.org/record/5382553 |journal=American Museum Novitates |issue=3455 |pages=1–22 |doi=10.1206/0003-0082(2004)455<0001:ROSDOC>2.0.CO;2 |s2cid=85575649 |hdl-access=free |hdl=2246/2765}}</ref> However, more recent studies indicate that ''Santanaichthys'' is likely a basal [[Otophysi|otophysan]] rather than a characiform. Similarly, ''[[Salminops]]'' from Spain and ''[[Sorbinicharax]]'' from Italy, previously also considered potential marine characiforms, are now thought to have no characiform affinities and are considered indeterminate [[Teleost|teleosts]]. Given this, there is no paleontological support for characiforms having marine origins.<ref>{{Cite journal |last1=Capobianco |first1=Alessio |last2=Friedman |first2=Matt |date=2019 |title=Vicariance and dispersal in southern hemisphere freshwater fish clades: a palaeontological perspective |url=https://onlinelibrary.wiley.com/doi/10.1111/brv.12473 |journal=Biological Reviews |language=en |volume=94 |issue=2 |pages=662–699 |doi=10.1111/brv.12473 |pmid=30338909 |hdl=2027.42/148368 |issn=1464-7931|hdl-access=free }}</ref><ref>{{Cite journal |last1=Mayrinck |first1=Diogo |last2=Brito |first2=Paulo M. |last3=Meunier |first3=François J. |last4=Alvarado-Ortega |first4=Jesus |last5=Otero |first5=Olga |date=2017-08-28 |title=†Sorbinicharax verraesi: An unexpected case of a benthic fish outside Acanthomorpha in the Upper Cretaceous of the Tethyan Sea |journal=PLOS ONE |language=en |volume=12 |issue=8 |pages=e0183879 |doi=10.1371/journal.pone.0183879 |doi-access=free |issn=1932-6203 |pmc=5573274 |pmid=28846739|bibcode=2017PLoSO..1283879M }}</ref>

Uniquely, Late Cretaceous characiform fossils are found significantly north of their modern distribution. Indeterminate characiform teeth are known from the Santonian of Hungary and [[Maastrichtian]] of France, which have a large, multi-cusped appearance reminiscent of African [[Alestidae|alestids]].<ref>{{Cite journal |last1=Szabó |first1=Márton |last2=Ősi |first2=Attila |date=2017-09-01 |title=The continental fish fauna of the Late Cretaceous (Santonian) Iharkút locality (Bakony Mountains, Hungary) |url=https://akjournals.com/view/journals/24/60/2/article-p230.xml |journal=Central European Geology |language=en-US |volume=60 |issue=2 |pages=230–287 |doi=10.1556/24.60.2017.009 |bibcode=2017CEJGl..60..230S |issn=1789-3348|hdl=10831/67493 |hdl-access=free }}</ref> Similarly, two [[Campanian]] freshwater characiform genera, ''[[Primuluchara]]'' and ''[[Eotexachara]]'', are known from North America, with ''Primuluchara'' having a very wide distribution across [[Laramidia]], ranging from Texas to as far north as southern Canada ([[Dinosaur Park Formation]]). It is likely that the warmer conditions of the Late Cretaceous allowed early characins to range farther north than the present day, with African characins colonizing Europe and South American characins colonizing North America. Early characins may have had some level of salt tolerance, allowing for such colonizations to take place.<ref>{{Cite journal |last=Wick |first=Steven L. |date=2021-12-01 |title=New early Campanian characiform fishes (Otophysi: Characiformes) from West Texas support a South American origin for known Late Cretaceous characiforms from North America |url=https://www.sciencedirect.com/science/article/pii/S019566712100241X |journal=Cretaceous Research |volume=128 |pages=104993 |doi=10.1016/j.cretres.2021.104993 |bibcode=2021CrRes.12804993W |issn=0195-6671}}</ref>  Within their modern distribution, a number of modern South American characin families have their earliest occurrences in the Maastrichtian of Bolivia, with isolated teeth and skeletal elements identifiable to [[Acestrorhynchus|Acestrorhynchidae]], [[Characidae]], and [[Serrasalmidae]].<ref name=":0" />

Characins appear to have inhabited Europe into the [[Paleogene]], with fossil teeth reminiscent of ''[[Alestes]]'' known from the [[Ypresian|Early Eocene]] of Spain.<ref>{{Cite journal |last=Zarzuelo |first=Antonio de la Peña |date=1996 |title=Characid Teeth from the Lower Eocene of the Ager Basin (Lérida, Spain): Paleobiogeographical Comments |url=https://www.jstor.org/stable/1447544 |journal=Copeia |volume=1996 |issue=3 |pages=746–750 |doi=10.2307/1447544 |issn=0045-8511}}</ref> ''[[Eurocharax]]'' <small>Gaudant, 1980</small> is known from a fully-articulated specimen from the [[Oligocene]] of France, and appears to represent an estuarine taxon, although its phylogenetic position needs revision.<ref>{{Cite journal |last=Gaudant |first=Jean |date=1980-01-01 |title=Eurocharax Tourainei nov. gen., nov. sp. (poisson teleosteen, Ostariophysi): Nouveau Characidae fossile des «Calcaires a Bythinies du Var |url=https://www.sciencedirect.com/science/article/abs/pii/S0016699580800519 |journal=Geobios |volume=13 |issue=5 |pages=683–703 |doi=10.1016/S0016-6995(80)80051-9 |issn=0016-6995}}</ref><ref name=":1">{{Citation |last=Cavender |first=T. M. |title=The fossil record of the Cyprinidae |date=1991 |work=Cyprinid Fishes: Systematics, biology and exploitation |pages=34–54 |editor-last=Winfield |editor-first=Ian J. |url=https://link.springer.com/chapter/10.1007/978-94-011-3092-9_2 |access-date=2025-04-24 |place=Dordrecht |publisher=Springer Netherlands |language=en |doi=10.1007/978-94-011-3092-9_2 |isbn=978-94-011-3092-9 |editor2-last=Nelson |editor2-first=Joseph S.}}</ref> Two other alleged Eocene European characids, ''[[Prohydrocyon]]'' <small>Piton, 1938</small> and ''[[Procharacinus]]'' <small>Piton, 1938</small> from France, lack a [[Weberian apparatus]] and are very likely not characins, and instead may be related to the enigmatic ''[[Thaumaturus]]''.<ref name=":1" /><ref>{{Cite journal |last=Novacek |first=Michael J. |last2=Marshall |first2=Larry G. |date=1976 |title=Early Biogeographic History of Ostariophysan Fishes |url=https://www.jstor.org/stable/1443767 |journal=Copeia |volume=1976 |issue=1 |pages=1–12 |doi=10.2307/1443767 |issn=0045-8511}}</ref>