Rattlesnakes are venomous snakes that form the genera Crotalus and Sistrurus of the subfamily Crotalinae. All rattlesnakes are vipers. Rattlesnakes are predators that live in a wide array of habitats, hunting small animals such as birds and rodents.
Rattlesnake
Western diamondback rattlesnake (Crotalus atrox), responsible for the majority of venomous snakebites in North America, coiled in defensive posture with rattle erect
1. Trigeminal nerve extending into the heat-sensing pit 2. Trigeminal nerve originating in the brain 3. Heat-sensing pit
Rattlesnake skull
Crotalus is a genus of venomous pit vipers, commonly known as rattlesnakes or rattlers, in the family Viperidae. The genus is found only in the Americas from southern Canada to northern Argentina. The generic name Crotalus is derived from the Greek word κρόταλον krótalοn, which means "rattle" or "castanet", and refers to the rattle on the end of the tail, which makes this group so distinctive. As of July 2023, 44 to 53 species are recognized as valid.
Crotalus
Image: Crotalus adamanteus 25
Image: Crotalus aquilus
Image: Crotalus atrox USFWS