This extremely rare species of rattlesnake is only known from just a handful of locations in Jailisco and Colima states. However, there is suspicion the original Jalisco specimen may have been found in Colima but erroneously labeled across the border in Autlán municipality.

It is restricted to the ecotones (ecosystem edges) between tropical deciduous forests and montane oak forests. It is currently threatened by mining activity and road mortality.

They are one of three "Long-tailed Rattlesnakes", notable for their proportionately long tails.