The Gray-bellied Grass Mouse occurs in northwestern Argentina and southern Bolivia. Its gray-brown back, pale throat, and two-toned tail are identifying features.
The back is grayish brown and may have yellowish or reddish tones, especially toward the rump. The flanks and belly are grayish white, white hairs occur on the chin and throat, and the tail is darker above than below.
In northwestern Argentina it is recorded in Yungas forest, highland grasslands, and the transition toward the Chaco. The identification key describes habitats but does not detail diet or daily behavior.
An extinction-risk assessment has not been added yet.