This medium to large rattlesnake occurs in temperate pine-oak forests to grasslands and lava beds within the Central Mexican Plateau. Their diet includes small mammals.

They can be distinguished from C. s. scutulatus by range, occupying areas of Mexico south of where their sister subspecies is found and pattern. Huamantlan rattlesnakes are usually darker, lacking the pale borders around their dorsal blotches, less contrast in the tail bands and sometimes a more "reddish" coloration in the face.

The venom of the Huamantlan rattlesnake seems to entirely consist of "Type A" venom, making it entirely neurotoxic, unlike the other subspecies, the Mojave rattlesnake, which has Type A, Type B, and Type A+B venom. These differences may correlate with different species of prey, feeding behaviors, and ecological niches!

This subspecies is categorized as Subject to Special Protection in Mexico, the lowest level of protection, due to factors that could negatively affect their population viability.