Acipenseriformes

Acipenseriformes; Temporal range:
	Atlantic sturgeon; (Acipenser oxyrhynchus)
	American paddlefish; (Polyodon spathula)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Subclass:	Chondrostei
Order:	Acipenseriformes; L. S. Berg, 1940
Subgroups
	Genus †Eochondrosteus?; Family †Chondrosteidae (sometimes placed in its own order); Family †Peipiaosteidae; Suborder Acipenseroidei Family Acipenseridae (sturgeon); Family Polyodontidae (paddlefish); ;

Acipenseriformes /æsɪˈpɛnsərɪfɔːrmiːz/ is an order of basal^[1] ray-finned fishes that includes living and fossil sturgeons and paddlefishes (Acipenseroidei), as well as the extinct families Chondrosteidae and Peipiaosteidae.^[2]^[3]^[4] They are the second earliest diverging group of living ray-finned fish after the bichirs. Despite being early diverging, they are highly derived, having only weakly ossified skeletons that are mostly made of cartilage, and in modern representatives highly modified skulls.^[5]

^ Venkatesh, B. (December 2003). "Evolution and diversity of fish genomes". Current Opinion in Genetics & Development. 13 (6): 588–592. doi:10.1016/j.gde.2003.09.001. PMID 14638319.
^ Froese, Rainer, and Daniel Pauly, eds. (2006). "Acipenseriformes" in FishBase. 05 2006 version.
^ Bemis, William E.; Findeis, Eric K.; Grande, Lance (1997). "An overview of Acipenseriformes". Environmental Biology of Fishes. 48 (1–4): 25–71. doi:10.1023/A:1007370213924. S2CID 24961905.
^ Lu, Liwu; Tan, Kai; Wang, Xi (2020). "Redescription of Eochondrosteus sinensis (Acipenseriformes, Actinopterygii) and its geological age". Earth Science Frontiers. 27 (6): 371–381.
^ Bemis, William E.; Findeis, Eric K.; Grande, Lance (2002), Birstein, Vadim J.; Waldman, John R.; Bemis, William E. (eds.), "An overview of Acipenseriformes", Sturgeon Biodiversity and Conservation, vol. 17, Dordrecht: Kluwer Academic Publishers, pp. 25–71, doi:10.1007/0-306-46854-9_4, ISBN 978-0-7923-4517-6, retrieved 2022-07-27

Acipenseriformes Temporal range:

Atlantic sturgeon (Acipenser oxyrhynchus)

American paddlefish (Polyodon spathula)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Subclass:	Chondrostei
Order:	Acipenseriformes L. S. Berg, 1940
Subgroups
Genus †Eochondrosteus? Family †Chondrosteidae (sometimes placed in its own order) Family †Peipiaosteidae Suborder Acipenseroidei Family Acipenseridae (sturgeon) Family Polyodontidae (paddlefish)