Crotalus is a genus of venomous pit vipers in the family Viperidae, known as rattlesnakes or rattlers. The genus is found only in the Americas from southern Canada to northern Argentina, and member species are colloquially known as rattlesnakes. The generic name Crotalus is derived from the Greek word κρόταλονkrótalοn, which means "rattle" or "castanet", and refers to the rattle on the end of the tail, which makes this group so distinctive. Currently, 32 to 62 species are recognized as being valid.
Sistrurus is a genus of venomous pit vipers in the subfamily Crotalinae of the family Viperidae. The genus is endemic to Canada, the United States, and Mexico. Its generic name is a Latinized form of the Greek word for "tail rattler" and shares its root with the ancient Egyptian musical instrument, the sistrum, a type of rattle. Three species are currently recognized.
The eastern massasauga is a rattlesnake species found in central and eastern North America from southern Ontario in Canada and throughout the Midwestern and Eastern United States. Like all rattlesnakes, it is a pit viper and is venomous.
Crotalus scutulatus is a highly venomous pit viper species found in the deserts of the southwestern United States and central Mexico. It is perhaps best known for its potent neurotoxic-hemotoxic venom, which is considered the world's most potent rattlesnake venom.
The black-tailed rattlesnake is a venomous pit viper species found in the southwestern United States and Mexico. Four subspecies are currently recognized, including the nominate subspecies described here.
Pantherophis vulpinus, commonly known as the eastern foxsnake or eastern fox snake, is a species of rat snake in the family Colubridae. The species is nonvenomous and is endemic to the eastern Great Lakes region of the United States, as well as adjacent western Ontario in Canada. Pantherophis gloydi is sometimes considered a distinct species and sometimes considered a junior synonym of the species Pantherophis vulpinus.
Crotalus basiliscus, known as the Mexican west coast rattlesnake, Mexican green rattler, and also by other names, is a species of pit viper in the family Viperidae. The species is endemic to western Mexico. Like all other pit vipers, it is venomous. The specific name, basiliscus, is derived from the Greek word for king, βασιλισκος, and alludes to this snake's large size and potent venom. No subspecies are currently recognized.
Crotalus helleri, known as the Southern Pacific rattlesnake, black diamond rattlesnake, and by other names, is a pit viper subspecies found in southwestern California and south into Baja California, Mexico, that is known for its regional variety of dangerous venom types.
Crotalus viridis is a venomous pit viper species native to the western United States, southwestern Canada, and northern Mexico. Currently, two subspecies are recognized, including the prairie rattlesnake, the nominate subspecies, and the Hopi rattlesnake.
Sistrurus miliarius, commonly called the pygmy rattlesnake, is a species of venomous snake in the subfamily Crotalinae of the family Viperidae. The species is endemic to the Southeastern United States. Three subspecies are currently recognized.
Crotalus viridis nuntius is a venomous pit viper subspecies native primarily to the desert plateau of the northeastern portion of the American state of Arizona, but also ranges into northwestern New Mexico. Named for the Native American Hopi tribe, which inhabits the region, its range overlaps that of the nominate subspecies and some interbreeding is believed to occur. The taxonomy of the C. viridis group is a matter of debate, many considering the various subspecies to be nothing more than locality variations.
Sistrurus tergeminus, also known as the western massasauga, is a rattlesnake found in the southwestern plains of the United States and northern Mexico. Like all rattlesnakes, it is a pit viper and is venomous.
Sistrurus miliarius barbouri is a venomous pit viper subspecies endemic to the southeastern United States.
Crotalus simus is a venomous pit viper species found in Mexico and Central America. The specific epithet is Latin for "flat-nosed", likely because its head is blunt compared with lanceheads (Bothrops). Three subspecies are recognized, including the nominate subspecies described here.
Crotalus oreganus, commonly known as the (northern) Pacific rattlesnake, is a venomous pit viper species found in western North America from the Baja California Peninsula to the southern interior of British Columbia.
Sistrurus miliarius streckeri is a venomous pit viper subspecies found in the southcentral United States.
The Great Basin rattlesnake is a venomous pit viper species found in the Great Basin region of the United States.
Crotalus pricei is a species of venomous snake, a pit viper in the family Viperidae. The species is endemic to the southwestern United States and northern Mexico. Two subspecies are recognized.
Lampropeltis getula, commonly known as the eastern kingsnake, common kingsnake, or chain kingsnake, is a harmless colubrid species endemic to the United States and Mexico. It has long been a favorite among collectors. Nine subspecies are currently recognized, including the nominate subspecies described here.
