A semiaquatic rodent of wetlands and farmland in southern South America. It has a reddish-brown back, a pale belly, and feeds on waterside plants and crops.
The back is deep orange to reddish brown, mixed with long blackish-brown hairs. The underside is white in northern populations; other accounts report grey or orange hairs, or a golden-yellow underside with white patches on the throat and chest.
It eats aquatic, riparian and cultivated plants. Spherical nests of leaves, sticks and grasses are recorded in vines, tree branches and wetland vegetation; galleries may also be dug near water level.
An extinction-risk assessment has not been added yet.