The Amiiformes

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

has only two

extant Extant or Least-concern species, least concern is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Exta ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

, the

bowfin The ruddy bowfin (''Amia calva'') is a ray-finned fish native to North America. Common names include mudfish, mud pike, dogfish, grindle, grinnel, swamp trout, and choupique. It is regarded as a relict, being one of only two surviving species ...

s: ''

Amia calva The ruddy bowfin (''Amia calva'') is a ray-finned fish native to North America. Common names include mudfish, mud pike, dogfish, grindle, grinnel, swamp trout, and choupique. It is regarded as a relict species, relict, being one of only two sur ...

'' and '' Amia ocellicauda'', the latter recognized as a separate species in 2022. These Amiiformes are found in the

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...

systems of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

, in the United States and parts of southern Canada. They live in freshwater streams, rivers, and swamps. The order first appeared in the Triassic, and the extinct members include both marine and freshwater species, many of which are morphologically disparate from bowfins, such as the caturids.

Evolution and diversity

The

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

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 preserve ...

s in

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

and

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

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

of Halecomorphi, the

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

to which the bowfin and its fossil relatives belong. Other orders, such as the Parasemionotiformes, are all extinct. Halecomorphs, and its

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

Ginglymodi, belong to

Holostei Holostei is a group of ray-finned bony fish. It is divided into two major clades, the Halecomorphi, represented by the single living genus, '' Amia'' with two species, the bowfins (''Amia calva'' and '' Amia ocellicauda''), as well as the Gin ...

. Holosteans are the sister group of teleosteans, the group to which nearly all (i.e., 96%) living

fishes A fish (: fish or fishes) is an aquatic, anamniotic, gill-bearing vertebrate animal with swimming fins and a hard skull, but lacking limbs with digits. Fish can be grouped into the more basal jawless fish and the more common jawed ...

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 language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

summarizes the evolutionary relationships of living and fossil Halecomorphs, and other neopterygians. Possible specimens of caturoids are known from the Late Triassic, with the earliest unambiguous members being known from the Early Jurassic. 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 genus, ''Amia'', containing the bowfin remained.

Taxonomy

* Order Amiiformes Hay, 1929 ** Genus †'' Guizhouamia'' Liu, Yin & Wang, 2002 ** Genus †'' Otomitla'' Felix, 1891 ** Genus †'' Paraliodesmus'' Dunkle, 1969 ** Superfamily † Caturoidea *** Genus †'' Eurypoma'' Huxley, 1866 *** Genus †'' Gymnoichthys''? Tintori ''et al.'', 2010 *** Genus †'' Liodesmus'' Wagner, 1859 *** Genus †'' Strobilodus'' Wagner, 1851 *** Family † Caturidae Owen, 1860 **** Genus †'' Catutoichthys'' Gouiric-Cavalli, 2016 **** Genus †'' Amblysemius'' Agassiz, 1844 **** Genus †'' Caturus'' Agassiz, 1834 ** Superfamily Amioidea Bonaparte, 1838 *** Genus †'' Amiidarum''? Lange, 1968 tolith*** Genus †'' Ferganamia''? Kaznyshkin, 1990 *** Genus †'' Lehmanamia''? Casier, 1966 *** Genus †'' Tomognathus'' Dixon, 1850 ***Family † Sinamiidae Berg, 1940 ****Genus †'' Ikechaoamia'' Liu, 1961 ****Genus †'' Siamamia'' Cavin ''et al.'', 2007 ****Genus †'' Sinamia'' Stensiö, 1935 *** Family

Amiidae The Amiidae are a family of basal ray-finned fishes. The bowfin and the eyespot bowfin ('' Amia ocellicauda'') are the only two species to survive today, although additional species in all four subfamilies of Amiidae are known from Jurassic, Cre ...

Bonaparte, 1837 **** Subfamily Amiinae Bonaparte, 1837 (sensu Grande & Bemis, 1998) ***** Genus '' Amia'' Linnaeus, 1766 ***** Genus †'' Cyclurus'' Agassiz, 1839 ***** Genus †'' Pseudamiatus'' Whitley, 1954 **** Subfamily † Amiopsinae Grande & Bemis, 1998 ***** Genus †'' Amiopsis'' Kner, 1863 **** Subfamily † Solnhofenamiinae Grande & Bemis, 1998 ***** Genus †'' Solnhofenamia'' Grande & Bemis, 1998 **** Subfamily † Vidalamiinae Grande & Bemis, 1998 ***** Tribe † Calamopleurini Grande & Bemis, 1998 ****** Genus †'' Calamopleurus'' Agassiz, 1841 ****** Genus †'' Maliamia'' Patterson & Longbottom, 1989 ***** Tribe † Vidalamiini Grande & Bemis, 1998 ****** Genus †'' Melvius'' Bryant, 1987 ****** Genus †'' Pachyamia'' Chalifa & Tchernov 1982 ****** Genus †'' Vidalamia'' White & Moy-Thomas, 1941 ****** Genus †'' Nipponamia'' Yabumoto, 1994

References

External links

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