The colouring varies somewhat between the subspecies but it is generally grey dorsally, the hairs having dark brown or black bases, and white or cream ventrally.

The upper part of the tail is blackish while the underside is dark with white tips to the hairs.

There is a pale ring of skin around the eyes, and an important identifying feature is the dentition, with one fewer upper premolars than other related species.

[3] This squirrel is endemic to Mexico where it is found in the provinces of Guanajuato, Hidalgo, México State, Puebla, Querétaro, San Luis Potosí and Veracruz.

The mating season seems to take place in summer and at this time, up to twenty individuals may accumulate in one tree, but little is known of their breeding behaviour.