This small species of rattlesnake has a total length of under two feet long. The cross-banded mountain rattlesnake only occurs in a very small portion of Central Mexico around the Sierra Ajusco and the Sierra de Monte Alto of the Transverse Volcanic Cordillera near Mexico City, Mexico. This species occurs at elevation above 9,500 ft.

There are only less than 20 specimens for this species in museums. Although their native range is extremely small and limited, their population trend is stable, and the cross-banded mountain rattlesnake is not threatened or endangered at this time.

Fun fact: These rattlesnakes have unusually long tails at up to 10% of their body length!