This snake can be found in the United States. This involves ranges across southern New Mexico, then to the far west Texas and in Sonora and Chihuahua Mexico.
They live in rocky habitats usually hillsides and mountain slopes. They are primarily a nocturnal specie. They also have venom which is used to immobilize their prey. Not much is known on their reproduction, but the females give birth to their eggs in the early summer. Lastly, their diet comprises of little mice, bats and lizards.
This snake grows up to 460 – 760 mm in total length. Although the longest recorded length is 1,040 mm. They have about 23 rows of dorsal scales. These are smooth and present at its mid-body. Also, these snakes are the only ones in Texas with a lorilabial scale in the middle of the loreal and upper labial scales. This specie has elliptical pupils. As regards their colouration, their dorsum is grey with about 21 brown crossbands on their trunks. These are also saddle-shaped and light coloured in the centre. The interspace distance is usually double the width of its crossbands. 1 – 3 brown spots are present on their heads or occasionally an incomplete V-shaped lyre. Also present is a row of dark spots at the dorsal or ventral scale contact.
Learn more with Schechter Natural History's Guide to Reptiles and Amphibians