This small rodent is known from southwestern Cerralvo Island, Mexico. Island specimens have black upper and side fur mixed with brown and pink underparts. It occurs on deep sandy soils, sandy stream beds, and in sarcocaule scrub.
Cerralvo Island specimens have black upper and side fur mixed with brown, a dark brown upper surface of the tail, and pink underparts. Their rump bristles are very weak and rarely present.
It is found on deep sandy soils and sandy stream beds, in sarcocaule scrub where plants of the spurge, cactus, and legume families are prominent.
An extinction-risk assessment has not been added yet.