Crotalus mitchellii, a venomous snake species commonly known as the speckled rattlesnake or Mitchell's rattlesnake, belongs to the Viperidae family. This species of snake predominantly inhabits the arid regions of Southwest United States and northern Mexico. Some of the synonyms which are used to refer to this species of snake include the following: Crotalus concinnus var. mitchellii, Crotalus confluentus var. mitchellii, Crotalus exsul mitchellii, Crotalus mitchellii lepturus, Crotalus lucasensis, Crotalus hoppii, and Crotalus mitchellii pyrrhus. These synonyms have been used to describe different variations and sub-species of the Crotalus mitchellii species which have been observed over time.