The Amiiformes order of

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of ...

has only one extant

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

, the bowfin (''Amia calva''). These Amiiformes are found in the freshwater systems of North America, in the United States and parts of southern Canada. They live in freshwater streams, rivers, and swamps. Bowfins are not on the endangered list. They have the ability to go to the surface to breathe air if the water level is too low. Characteristics of Amiiformes are a cylindrical body with a long

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

, single gular plate, heterocercal caudal fin, 10 to 13 flattened branchiostegal rays, maxilla included in gape, and prominent

ocellus A simple eye (sometimes called a pigment pit) refers to a form of eye or an optical arrangement composed of a single lens and without an elaborate retina such as occurs in most vertebrates. In this sense "simple eye" is distinct from a multi-l ...

near upper base of

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

Evolution and diversity

The extinct species of the Amiiformes can be found as

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s in

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

and

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

, but the bowfin is the last living species in the order. Amiiformes is therefore the last surviving order of

Halecomorphi Halecomorphi is a taxon of ray-finned bony fish in the clade Neopterygii. The sole living Halecomorph is the bowfin (''Amia calva''), but the group contains many extinct species in several families (including Amiidae, Caturidae, Liodesmidae ...

, the clade to which the bowfin and its fossil relatives belong. Other orders, such as the

Parasemionotiformes Parasemionotiformes is an extinct order of neopterygian ray-finned fish that existed globally during the Triassic period. It comprises the families Parasemionotidae and Promecosominidae. Many of the included genera are monotypic and most specie ...

, are all extinct. Halecomorphs, and its sister group

Ginglymodi Ginglymodi is a clade of ray-finned fish containing modern-day gars (Lepisosteidae) and their extinct relatives, including the family Lepidotidae and the orders Semionotiformes and Kyphosichthyiformes, and various other extinct taxa. Ginglymod ...

, belong to

Holostei Holostei is a group of ray-finned bony fish. It is divided into two major clades, the Halecomorphi, represented by a single living species, the bowfin ('' Amia calva''), as well as the Ginglymodi, the sole living representatives being the gars ...

. Holosteans are the sister group of

teleosteans Teleostei (; Ancient Greek, Greek ''teleios'' "complete" + ''osteon'' "bone"), members of which are known as teleosts ), is, by far, the largest class (biology), infraclass in the class Actinopterygii, the ray-finned fishes, containing 96% of a ...

, the group to which nearly all (i.e., 96%) living

fishes Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

belong to. Holosteans and Teleosts form a clade called

Neopterygii 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 ...

. The following

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...

summarizes the

evolutionary relationships Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation t ...

of living and fossil Halecomorphs, and other neopterygians. Amiiformes likely originated in the western

Tethys Ocean The Tethys Ocean ( el, Τηθύς ''Tēthús''), also called the Tethys Sea or the Neo-Tethys, was a prehistoric ocean that covered most of the Earth during much of the Mesozoic Era and early Cenozoic Era, located between the ancient continents ...

, in what is now Europe. The oldest member of the Amiiformes is ''

Caturus heterurus ''Caturus'' (from el, κατω , 'down' and el, οὐρά 'tail') is an extinct genus of fishes in the Family (biology), family Caturidae in the order Amiiformes, related to modern bowfin. Fossils of this genus range from 200 to 109 mya. It ha ...

'' from the lower

Lias Lias may refer to: Geology * Lias Formation, a geologic formation in France *Lias Group, a lithostratigraphic unit in western Europe * Early Jurassic, an epoch People * Godfrey Lias, British author * Mohd Shamsudin Lias (born 1953), Malaysian ...

(

Sinemurian In the geologic timescale, the Sinemurian is an age and stage in the Early or Lower Jurassic Epoch or Series. It spans the time between 199.3 ± 2 Ma and 190.8 ± 1.5 Ma (million years ago). The Sinemurian is preceded by the Hettangian and ...

) of England. Amiiformes had spread to North America and Africa by the end of the Middle Jurassic, reaching an apex of diversity during the Early Cretaceous, during the Late Cretaceous and Cenozoic, the group declined until only a single species, the bowfin remained.

Taxonomy

* Order Amiiformes Hay 1929 **Genus †'' Guizhouamia'' Liu, Yin & Wang 2002 ** Genus †'' Stromerichthys'' Weiler 1935 ** Superfamily † Caturoidea *** Family † Liodesmidae Jordan 1905 **** Genus †'' Paraliodesmus'' Dunkle 1969 **** Genus †'' Liodesmus'' Wagner 1859 'Lophiurus''_Vetter_1881.html" ;"title="Lophiurus.html" ;"title="' 'Lophiurus''_Vetter_1881">Lophiurus.html"_;"title="'Lophiurus">'Lophiurus''_Vetter_1881***_Family_†Caturidae.html" ;"title="Lophiurus">'Lophiurus'' Vetter 1881">Lophiurus.html" ;"title="'Lophiurus">'Lophiurus'' Vetter 1881*** Family †Caturidae">Lophiurus">'Lophiurus'' Vetter 1881">Lophiurus.html" ;"title="'Lophiurus">'Lophiurus'' Vetter 1881*** Family †Caturidae Owen 1860 corrig. **** Genus ?†''Allolepidotus'' (Deecke 1889) [''Heterolepidotus'' (''Allolepidotus'') Deecke 1889; ''Plesiolepidotus'' Schlosser 1923] **** Genus ?†''Catutoichthys'' Gouiric-Cavalli 2016 **** Genus ?†'' Ditaxiodus'' Owen 1866 **** Genus ?†'' Eoeugnathus'' Brough 1939 **** Genus ?†'' Guizhoueugnathus'' Liu 2004 **** Genus ?†'' Harpactira'' Egerton 1876 'Harpactes''_Egerton_1876_non_Swainson_1833_non_Templeton_1834_non_Menetries_1848.html" ;"title="Harpactes.html" ;"title="'Harpactes">'Harpactes'' Egerton 1876 non Swainson 1833 non Templeton 1834 non Menetries 1848">Harpactes.html" ;"title="'Harpactes">'Harpactes'' Egerton 1876 non Swainson 1833 non Templeton 1834 non Menetries 1848**** Genus ?†''Plesiofuro'' Su 1993 **** Genus ?†''Sinoeugnathus'' Su 1959 **** Genus ?†''Thlattodus'' Owen 1866 **** Genus ?†''Xingyia'' Liu et al. 2003 **** Genus †'' Amblysemius'' Agassiz 1844 **** Genus †''

Caturus ''Caturus'' (from el, κατω , 'down' and el, οὐρά 'tail') is an extinct genus of fishes in the family Caturidae in the order Amiiformes, related to modern bowfin. Fossils of this genus range from 200 to 109 mya. It has been suggested ...

'' Agassiz 1834 'Uraeus''_Agassiz_1832_non_Wagler_1830;_''Strobilodus.html" ;"title="Uraeus.html" ;"title="'Uraeus">'Uraeus'' Agassiz 1832 non Wagler 1830; ''Strobilodus">Uraeus.html" ;"title="'Uraeus">'Uraeus'' Agassiz 1832 non Wagler 1830; ''Strobilodus'' Wagner 1851; ''Endactis'' Egerton 1858 non Rafinesque 1820; ''Conodus'' Woodward 1895 non Gervais 1869; ''Conodus'' Agassiz 1841 nomen nudum] **** Genus †''Furo (fish), Furo'' Gistl 1848 'Eugnathus''_Agassiz_1844_non_Schönherr_1833;_''Eugnathus''_Agassiz_1836_nomen_nudum;_''Isopholis.html" ;"title="Eugnathus.html" ;"title="'Eugnathus">'Eugnathus'' Agassiz 1844 non Schönherr 1833; ''Eugnathus'' Agassiz 1836 nomen nudum; ''Isopholis">Eugnathus.html" ;"title="'Eugnathus">'Eugnathus'' Agassiz 1844 non Schönherr 1833; ''Eugnathus'' Agassiz 1836 nomen nudum; ''Isopholis'' Zittel 1887] **** Genus †''Heterolepidotus'' Egerton 1872 [''Eulepidotus'' Egerton 1868 non Herrich-Schaeffer 1850-1856; ''Brachyichthys'' Winkler 1862] **** Genus †'' Neorhombolepis'' Woodward 1888 **** Genus †'' Osteorachis'' Egerton 1868 **** Genus †'' Otomitla'' Felix 1891 ** Superfamily Amioidea Bonaparte 1838 *** Genus ?†'' Amiidarum'' Lange 1968 tolith*** Genus ?†'' Ferganamia'' Kaznyshkin 1990 *** Genus ?†'' Lehmanamia'' Casier 1966 ***Family

Sinamiidae Sinamiidae is an extinct family of ray-finned fish. They are halecomorph fishes endemic to Early Cretaceous freshwater environments in eastern Asia. Along with Amiidae, it is one of two families that makes up the superfamily Amioidea The Ami ...

Berg, 1940 ****Genus †''

Siamamia ''Siamamia'' is an extinct genus of ray-finned fish from Northeasthern Thailand. They belong to family Sinamiidae and are halecomorph fishes endemic to Early Cretaceous freshwater environments in eastern Asia. ''Siamamia'' fossils have been f ...

'' Cavin, Suteethorn, Buffetaut, Claude, Cuny, Le Loeuff and

Tong Tong may refer to: Chinese *Tang Dynasty, a dynasty in Chinese history when transliterated from Cantonese *Tong (organization), a type of social organization found in Chinese immigrant communities *''tong'', pronunciation of several Chinese char ...

2007 ****Genus †''

Sinamia ''Sinamia'' is an extinct genus of amiiform fish which existed in China, Japan, and possibly South Korea during the Early Cretaceous period. Like the related bowfin, it has an elongated low-running dorsal fin, though this was likely convergentl ...

'' Stensiö, 1935 *** Family

Amiidae The Amiidae are a family of basal ray-finned fishes. The bowfin is the only species to survive today, although additional species in all four subfamilies of Amiidae are known from Jurassic, Cretaceous, and Eocene fossils. Bowfins are now found ...

Bonaparte 1837 **** Subfamily

Amiinae The Amiidae are a family of basal ray-finned fishes. The bowfin is the only species to survive today, although additional species in all four subfamilies of Amiidae are known from Jurassic, Cretaceous, and Eocene fossils. Bowfins are now found ...

Bonaparte 1837 sensu Grande & Bemis 1998 ***** Genus ''

Amia Amia, AMIA, or AMiA may refer to: * ''Amia'' (fish), a genus of fish *American Medical Informatics Association * Anglican Mission in the Americas *Asociación Mutual Israelita Argentina, a Jewish community center in Buenos Aires, Argentina **AMIA ...

'' Linnaeus 1766 non Browne 1756 ex Browne 1789 non Gronow 1763 ex Gray 1854 non Meuschen 1781; '' Amiatus'' Rafinesque 1815; '' Hypamia'' (Leidy 1873); ''Amia'' (''Hypamia'') Leidy 1873; '' Kindleia'' Jordan 1927; '' Protamia'' (Leidy 1873); ''Amia'' (''Protamia'') Leidy 1873; '' Stylomyleodon'' Russell 1928] ***** Genus †'' Cyclurus'' Agassiz 1839 'Notaeus''_Agassiz_1843.html" ;"title="Notaeus.html" ;"title="' 'Notaeus''_Agassiz_1843">Notaeus.html"_;"title="'Notaeus">'Notaeus''_Agassiz_1843*****_Genus_†''Pseudamiatus.html" ;"title="Notaeus">'Notaeus'' Agassiz 1843">Notaeus.html" ;"title="'Notaeus">'Notaeus'' Agassiz 1843***** Genus †''Pseudamiatus">Notaeus">'Notaeus'' Agassiz 1843">Notaeus.html" ;"title="'Notaeus">'Notaeus'' Agassiz 1843***** Genus †''Pseudamiatus'' Whitley 1954 [''Pseudamia'' Lehman 1951 non Bleeker 1865] **** Subfamily †Amiopsinae Grande and Bemis 1998 ***** Genus †''Amiopsis'' Kner 1863 [''Urocles''] **** Subfamily † Solnhofenamiinae Grande and Bemis 1998 ***** Genus †'' Solnhofenamia'' Grande and Bemis 1998 (type) **** Subfamily †

Vidalamiinae The Amiidae are a family of basal ray-finned fishes. The bowfin is the only species to survive today, although additional species in all four subfamilies of Amiidae are known from Jurassic, Cretaceous, and Eocene fossils. Bowfins are now found ...

Grande and Bemis 1998 ***** Tribe † Calamopleurini Grande and Bemis 1998 ****** Genus †''

Calamopleurus ''Calamopleurus'' is an extinct genus of bowfins, comprising three species: ''C. cylindricus'' and ''C. mawsoni'' from Brazil and ''C. africanus'' from Africa Africa is the world's second-largest and second-most populous continent, af ...

'' Agassiz 1841 'Enneles''_Jordan_&_Branner_1908.html" ;"title="Enneles.html" ;"title="' 'Enneles''_Jordan_&_Branner_1908">Enneles.html"_;"title="'Enneles">'Enneles''_Jordan_&_Branner_1908******_Genus_†''Maliamia.html" ;"title="Enneles">'Enneles'' Jordan & Branner 1908">Enneles.html" ;"title="'Enneles">'Enneles'' Jordan & Branner 1908****** Genus †''Maliamia">Enneles">'Enneles'' Jordan & Branner 1908">Enneles.html" ;"title="'Enneles">'Enneles'' Jordan & Branner 1908****** Genus †''Maliamia'' Patterson and Longbottom 1989 ***** Tribe †Vidalamiini Grande and Bemis 1998 ****** Genus †''Melvius'' Bryant 1987 ****** Genus †''Pachyamia'' Chalifa and Tchernov 1982 ****** Genus †''Vidalamia'' White and J. A. Moy-Thomas, Moy-Thomas 1941 Vidalia''_le_Sauvage1903_non_Robineau-Desvoidy_1830_non_Lamouroux_ex_Agardh_1863.html" ;"title="Vidalia_(fly).html" ;"title="'Vidalia (fly)">Vidalia'' le Sauvage1903 non Robineau-Desvoidy 1830 non Lamouroux ex Agardh 1863">Vidalia_(fly).html" ;"title="'Vidalia (fly)">Vidalia'' le Sauvage1903 non Robineau-Desvoidy 1830 non Lamouroux ex Agardh 1863****** Genus †''Nipponamia'' Yabumoto 1994

References

External links

{{Taxonbar, from=Q3314611 Amiiformes, Articles which contain graphical timelines Ray-finned fish orders