[3] The lower surfaces of the feet have thick pads with leathery tubercles, which help the animal gain traction on bare rock.

[1] The region is a rocky desert, dominated by shrubs and cacti, and the animal has been found between elevations of 1,100 and 2,900 m (3,600 and 9,500 ft).

The Sierra del Tontal chinchilla rat is thought to be primarily diurnal, being most active in the early morning, and live in groups of three to four individuals.

They shelter in rocky crevices on east-facing slopes, and deposit their faeces in large latrines.

[3] Like the related Punta de Vacas chinchilla rat,[6] the Sierra del Tontal species has a pair of "false teeth" in the mid-line of its palate, which apparently help with food manipulation and are aided by a horny pad on the tongue.