Order Squamata, Suborder Serpentes


All of North America's venomous snakes, except coral snakes, are pit vipers (family Crotalidae).  North American pit vipers have a deep, heat-sensitive loreal "pit" located between the eyes and nostrils of the snake (seen clearly on the copperhead), and front hinged fangs with a mostly hemotoxic venom which affects the muscle tissue and circulatory system.  Coral snakes belong to the family Elapidae, front fixed fangs with a mostly neurotoxic venom which affects the central nervous system.  Other elapids include the cobras and mambas.

Agkistrodon contortrix
Juvenile Cottonmouth
Agkistrodon piscivorus
Agkistrodon piscivorus
Pigmy Rattlesnake
Sistrurus miliarius
Sistrurus catenatus
Western Diamondback
Crotalus atrox
Prairie Rattlesnake
Crotalus viridis
Timber Rattlesnake
Crotalus horridus


Family Colubridae - harmless, egg-laying snakes (oviparous)
Pituophis catenifer
Great Plains
Rat Snake

Pantherophis emoryi
Western Black
Rat Snake

Scotophis obsoletus
Speckled Kingsnake
Lampropeltis getula
Prairie Kingsnake
Lampropeltis calligaster
Coluber constrictor
Plains Blackhead

Tantilla nigriceps
Ground Snake
Sonora semiannulata
Rough Green Snake
Opheodrys aestivus
Milk Snake
Lampropeltis triangulum
Coluber flagellum

Family Natricidae - harmless, live-bearing snakes (ovoviviparous)
Lined Snake
Tropidiclonion lineatum
Western Ribbon Snake
Thamnophis proximus
Plains Garter Snake
Thamnophis radix

Blotched Water Snake
Nerodia erythrogaster
Diamondback Water Snake
Nerodia rhombifer
Banded Water Snake
Nerodia sipedon
Broadbanded Water Snake
Nerodia fasciata

Family Xenodontidae - robust, rear-fanged snakes
Western Hognose Snake
Heterodon nasicus
Eastern Hognose Snake
Heterodon platirhinos

Family Dipsadidae - slender, rear-fanged snakes
Western Worm Snake
Carphophis vermis
Ringneck Snake
Diadophis punctatus