Eastern copperhead

Eastern copperhead
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Viperidae
Genus:	Agkistrodon
Species:	A. contortrix
Binomial name
Agkistrodon contortrix (Linnaeus, 1766)
Synonyms[2]
Boa contortrix Linnaeus, 1766 Scytale contortrix — Sonnini & Latreille, 1801 Scytale Cupreus Rafinesque, 1818 Scytale cupreus — Say, 1819 Tisiphone cuprea — Fitzinger, 1826 [Cenchris] marmorata F. Boie, 1827 Acontias atrofuscus Troost, 1836 [Toxicophis atrofuscus] — Troost, 1836 T[rigonocephalus] cenchris Schlegel, 1837 Trigonocephalus Contortrix — Holbrook, 1838 Trigonocephalus atro-fuscus — Holbrook, 1842 Cenchris contortrix — Gray, 1842 Cenchris atrofuscus — Gray, 1849 Agkistrodon contortrix — Baird & Girard, 1853 T[rigonocephalus] histrionicus A.M.C. Duméril & Bibron, 1853 Ancistrodon contortrix — Baird, 1854 Agkistrodon contorting Abbott, 1869 (ex errore) Ancistrodon atrofuscus — Cope, 1875 Agkistrodon atrofuscus — Yarrow, 1882 [Ancistrodon contortrix] Var. atrofuscus — Garman, 1884 Ancistrodon contortrix — Boulenger, 1896 Agkistrodon contortirix Keim, 1914 (ex errore) Agkistrodon mokasen cupreus — Gloyd & Conant, 1938 Agkistrodon contortrix contortrix — Klauber, 1967 Ancistrodon contortrix contortrix — Schmidt, 1953

The eastern copperhead (Agkistrodon contortrix),^[3] also known simply as the copperhead, is a species of venomous snake, a pit viper, endemic to eastern North America; it is a member of the subfamily Crotalinae in the family Viperidae.

The eastern copperhead has distinctive, dark brown, hourglass-shaped markings, overlaid on a light reddish brown or brown/gray background. The body type is heavy, rather than slender. Neonates are born with green or yellow tail tips, which progress to a darker brown or black within one year. Adults grow to a typical length (including tail) of 50–95 cm (20–37 in).

In most of North America, the eastern copperhead favors deciduous forest and mixed woodlands. It may occupy rock outcroppings and ledges, but is also found in low-lying, swampy regions. During the winter, it hibernates in dens or limestone crevices, often together with timber rattlesnakes and black rat snakes.^[4] The eastern copperhead is known to feed on a wide variety of prey, including invertebrates (primarily arthropods) and vertebrates. Like most pit vipers, the eastern copperhead is generally an ambush predator; it takes up a promising position and waits for suitable prey to arrive.

As a common species within its range, it may be encountered by humans. Unlike other viperids, it often "freezes" instead of slithering away and fleeing, due to its habit of relying on excellent camouflage.^[5] Bites occur due to people unknowingly stepping on or near them.^[6] Copperhead bites account for half of the treated snake bites in the United States.^[7]

Five subspecies have been recognized in the past,^[8] but recent genetic analysis had yielded new species information.