Bowfin

Bowfin
Bowfin in aquarium
Conservation status
Least Concern  (IUCN 3.1)[1]
Unranked (NatureServe)[2]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Clade:	Halecomorphi
Order:	Amiiformes
Family:	Amiidae
Genus:	Amia
Species:	A. calva
Binomial name
Amia calva Linnaeus, 1766
Synonyms[3][4]
Species Amia occidentalis DeKay 1842 Amia marmorata Valenciennes 1847 Amia ornata Valenciennes 1847 Amia viridis Valenciennes 1847 Amia cinerea Valenciennes 1847 Amia reticulata Valenciennes 1847 Amia canina Valenciennes 1847 Amia lintiginosa Valenciennes 1847 Amia subcoerulea Valenciennes 1847 Amia thompsonii Duméril 1870 Amia piquotii Duméril 1870 Amiatus calvus (Linnaeus 1766)

The bowfin (Amia calva) is a bony 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 of the Halecomorphi, a group of fish that first appeared during the Early Triassic, around 250 million years ago. The bowfin is often considered a "primitive fish" because they have retained some morphological characteristics of their early ancestors. It is one of two species in the genus Amia, along with Amia ocellicauda,^[5] the eyespot bowfin. The closest living relatives of bowfins are gars, with the two groups being united in the clade Holostei.

Bowfins are demersal freshwater piscivores, commonly found throughout much of the eastern United States,^[2] and in southern Ontario and Quebec. Fossil deposits indicate Amiiformes were once widespread in both freshwater and marine environments across North and South America, Europe, Asia, and Africa. Now, their range is limited to much of the eastern United States and adjacent southern Canada, including the drainage basins of the Mississippi River, Great Lakes, and various rivers exiting in the Eastern Seaboard or Gulf of Mexico. Their preferred habitat includes vegetated sloughs, lowland rivers and lakes, swamps, and backwater areas; they are also occasionally found in brackish water. They are stalking, ambush predators known to move into the shallows at night to prey on fish and aquatic invertebrates such as crawfish, mollusks, and aquatic insects.

Like gars, bowfin are bimodal breathers—they have the capacity to breathe both water and air. Their gills exchange gases in the water allowing them to breathe, but they also have a gas bladder that serves to maintain buoyancy, and also allows them to breathe air by means of a small pneumatic duct connected from the foregut to the gas bladder. They can break the surface to gulp air, which allows them to survive conditions of aquatic hypoxia that would be lethal to most other species. The bowfin is long-lived, with age up to 33 years reported.^[6]