This rodent occurs in southern Chile and western Argentina. Coat color varies geographically, but grayish fur and a brown band along the back are reported. It has been recorded in forests as well as steppe.
Coat color varies geographically, but the revised diagnosis describes it as usually grayish, with a more or less distinct band of brown hairs along the mid-back. The belly is whitish or gray, with a clear boundary from the back.
A 2021 study of A. hirta sampled the species in sclerophyllous shrubland, Valdivian and Magellanic forests, and Patagonian steppe.
An extinction-risk assessment has not been added yet.