The Big-headed Rice Rat has yellowish to orange-brown fur across its back. It occurs in forests on the eastern Andean slopes of central and southern Bolivia and northwestern Argentina.
The back is yellowish brown to orange brown, with an orange line along the flanks and cheeks. A thin dark ring surrounds the eyes, and the tail is darker above than below.
It is recorded in premontane and montane forest on the eastern slopes of the Andes, from about 500 to 2,100 m. The cited redescription does not detail its diet or daily activity.
An extinction-risk assessment has not been added yet.