Crotalus cerastes, known as the sidewinder, horned rattlesnake or sidewinder rattlesnake, is a pit viper species belonging to the genus Crotalus, and is found in the desert regions of the Southwestern United States and northwestern Mexico. Like all other pit vipers, it is venomous. Three subspecies are currently recognized.
The Crotalinae, commonly known as pit vipers, or pit adders, are a subfamily of vipers found in Asia and the Americas. Like all other vipers, they are venomous. They are distinguished by the presence of a heat-sensing pit organ located between the eye and the nostril on both sides of the head. Currently, 23 genera and 155 species are recognized: These are also the only viperids found in the Americas. The groups of snakes represented here include rattlesnakes, lanceheads, and Asian pit vipers. The type genus for this subfamily is Crotalus, of which the type species is the timber rattlesnake, C. horridus.
Crotalus stephensi is a venomous pitviper species found in central and southern Nevada and adjacent California. Common names include panamint rattlesnake, panamint rattler, Owens Valley rattler, and tiger rattlesnake.
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.
Crotalus helleri or Crotalus oreganus helleri, also known commonly as the Southern Pacific rattlesnake, the black diamond rattlesnake, and by several other common names, is a pit viper species or subspecies found in southwestern California and south into Baja California, Mexico, that is known for its regional variety of dangerous venom types. It is sometimes considered a subspecies of Crotalus oreganus.
Crotalus ruber is a venomous pit viper species found in southwestern California in the United States and Baja California in Mexico. Three subspecies are currently recognized, including the nominate subspecies described here.
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.
Crotalus oreganus abyssus is a venomous pit viper subspecies found only in the U.S. states of Arizona and Utah.
Crotalus oreganus, commonly known as the Western rattlesnake or 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.
The Great Basin rattlesnake is a venomous pit viper species found in the Great Basin region of the United States.
Crotalus intermedius omiltemanus is a venomous pitviper subspecies found in Mexico in the state of Guerrero.
Crotalus intermedius gloydi is a subspecies of venomous pitviper in the family Viperidae. The subspecies is endemic to Mexico in the states of Oaxaca and Puebla.
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.
Crotalus cerastes cercobombus, commonly known as the Sonoran Desert sidewinder or Sonoran sidewinder, is a pitviper subspecies found in the eastern part of the Sonoran Desert in the southwestern United States and northwestern Mexico. Like all pitvipers, it is venomous. The subspecific epithet means buzzertail.
Crotalus cerberus is a venomous pit viper species found in the southwestern United States. It is known as the Arizona black rattlesnake, black rattlesnake, and several other common names.
Crotalus willardi obscurus is a venomous pitviper subspecies found in northwestern Mexico and the Southwestern United States.
Porthidium nasutum is a venomous pitviper species found in southern Mexico, Central America and northern South America. No subspecies are currently recognized.
Crotalus pyrrhus is a venomous pitviper species found in the southwestern United States and northwestern Mexico. A medium-sized snake, it is found mostly in rocky country, active at night and feeding on small mammals. The coloration is variable and depends on the color of the rocks and soil of the habitat.
Crotalus ruber lucasensis, the San Lucan diamond rattlesnake, is a venomous pitviper subspecies found in Mexico in the Cape region of lower Baja California.
