This small rodent has been recorded on Wellington Island and nearby mainland in the Patagonian channels of southern Chile. It has long, dense fur, a gray-brown to brown back, and a pale band that reaches the sides of the nose.
Its fur is long, smooth, and dense. The back ranges from gray-brown to brown; a pale brown-to-yellow band along the sides extends to the sides of the nose. The underside is gray, and the tail is dark above, pale brown at the sides, and gray below.
The 2008 paper records this geographic form as syntopic with Oligoryzomys longicaudatus. It describes evergreen Nothofagus, Drimys and Lomatia forest, with a Tepualia and Blechnum understorey, in the two areas where it occurs.
An extinction-risk assessment has not been added yet.