Belongs within: Actinopteri.
The Acipenseriformes, sturgeons and related forms, are an order of fishes united by hyostylic jaw suspension and losses of endochondral ossification, dermal cheek bones, and trunk scalation (Findeis 1997).
<==Acipenseriformes [Chondrostei] | i. s.: Stychopterus popoviV-RR93 |--Peipiaosteus [Peipiaosteidae]F97 | |--P. fengningensisSD11 | `--P. pani Liu & Zhou 1965F97 |--ChondrosteoideiF97 | |--ErrolichthyidaeB96 | `--ChondrosteidaeF97 | |--Strongylosteus hindenburgi (Pompeckz 1914)G93 | |--GyrosteusG93 | | |--G. mirabilis Egerton 1858G93 | | `--G. subdeltoideus Stinton & Torrens 1968G93 | `--Chondrosteus Egerton 1858F97 | |--C. acipenseroides Agassiz 1844F97 | |--C. hindenburgiF97 | `--C. pachyurus Egerton 1858G93 `--AcipenseroideiF97 |--PolyodontidaeF97 | |--Polyodon spathulaF97 | |--Psephurus gladius (Martens 1862)F97 | |--Crassopholis magnicaudata Cope 1883G93 | |--Protopsephurus liuiNE12 | `--Paleopsephurus wilsoni McAlpin 1947F97, G93 `--AcipenseridaeF97 |--Huso Brandt 1869 [Husinae]F97 | |--H. dauricusF97 | `--H. huso (Linnaeus 1758)F97 `--AcipenserinaeF97 |--Scaphirhynchini [Scaphirhynchinae]F97 | |--Protoscaphirhynchus squamosusF97 | |--Pseudoscaphirhynchus Nikolskii 1900F97 | | |--P. fedtschenkoiF97 | | |--P. hermanniF97 | | `--P. kaufmanniF97 | `--Scaphirhynchus Heckel 1836F97 | |--S. albusF97 | |--S. platorynchusF97 | `--S. suttkusiF97 `--Acipenser Linnaeus 1758 [Acipenserini]F97 |--A. baeriiF97 |--A. brevirostrum LeSueur 1818M02 |--A. fulvescensF97 |--A. gueldenstaedtii Brandt & Ratzeberg 1833SE08 |--A. huso Linnaeus 1758L58 |--A. medirostrisF97 |--A. naccariiB96 |--A. nudiventris Lovetzky 1828SE08 |--A. oxyrinchus Mitchill 1815 [=A. oxyrhynchus (l. c.)]M02 | |--A. o. oxyrinchus [=A. sturio oxyrinchus]M02 | `--A. o. desotoi [=A. sturio desotoi]M02 |--A. plecostomus Linnaeus 1758L58 |--A. ruthenus Linnaeus 1758SE08 |--A. schypaC01 |--A. stellatus Pallas 1771SE08 |--A. sturio Linnaeus 1758L58 `--A. transmontanusF97
*Type species of generic name indicated
References
[B96] Bond, C. E. 1996. Biology of Fishes 2nd ed. Saunders College Publishing: Fort Worth.
[C01] Csiki, E. 1901. Utivázlat [Reiseskizze]. In: Horváth, G. (ed.) Zichy Jenő Gróf Harmadik Ázsiai Utazása [Dritte Asiatische Forschungsreise des Grafen Eugen Zichy] vol. 2. Zichy Jenő Gróf Harmadik Ázsiai Utazásának Állattani Eredményei [Zoologische Ergebnisse der Dritten Asiatischen Forschungsreise des Grafen Eugen Zichy] pp. xii–xli. Victor Hornyánszky: Budapest, and Karl W. Hierseman: Leipzig.
[F97] Findeis, E. K. 1997. Osteology and phylogenetic interrelationships of sturgeons (Acipenseridae). Environmental Biology of Fishes 48: 73–126.
[G93] Gardiner, B. G. 1993. Osteichthyes: basal actinopterygians. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 611–619. Chapman & Hall: London.
[L58] Linnaeus, C. 1758. Systema Naturae per Regna Tria Naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. Laurentii Salvii: Holmiae.
[M02] Musick, J. A. 2002. Sturgeons. Family Acipenseridae. In: Collette, B. B., & G. Klein-MacPhee (eds) Bigelow and Schroeder’s Fishes of the Gulf of Maine 3rd ed. pp. 83–88. Smithsonian Institute Press: Washington.
[NE12] Near, T. J., R. I. Eytan, A. Dornburg, K. L. Kuhn, J. A. Moore, M. P. Davis, P. C. Wainwright, M. Friedman & W. L. Smith. 2012. Resolution of ray-finned fish phylogeny and timing of diversification. Proceedings of the National Academy of Sciences of the USA 109 (34): 13698–13703.
[SE08] Sevcsik, A., & T. Erös. 2008. A revised catalogue of freshwater fishes of Hungary and the neighbouring countries in the Hungarian Natural History Museum (Pisces). Annales Historico-Naturales Musei Nationalis Hungarici 100: 331–383.
[SD11] Sun, G., D. L. Dilcher, H. Wang & Z. Chen. 2011. A eudicot from the Early Cretaceous of China. Nature 471: 625–628.
[V-RR93] Vickers-Rich, P., & T. H. Rich. 1993. The ICI Australia Catalogue of the Great Russian Dinosaurs Exhibition 1993–1995. Monash University.