Common names: western diamondback rattlesnake, Texas diamond-back, more.

Crotalus atrox, the western diamondback rattlesnake, is a venomous rattlesnake species found in the United States and Mexico. It is likely responsible for the majority of snakebite fatalities in northern Mexico and the second-greatest number in the U.S., after C. adamanteus. No subspecies is currently recognized.