The upper parts are gray to black, with a white spot above each eye, and the underparts vary from yellowish to buffy white. The tail, which is furred for about 50-60 mm from the rump and naked toward the tip, is black or grayish black on its basal half and white toward the end, with a pink tip. The body is slim and usually lean, and the head is large, with an elongate, conical muzzle. The ears are naked. The tail is slender, tapering, and prehensile.
Females have a distinct pouch.
The number of mammae varies from five to nine. These opossums inhabit forested areas and are often found near swamps and rivers. They are smaller and more agile than Didelphis and quick in their actions. Although good climbers and swimmers, they are mainly terrestrial. They build globular nests, about 30 cm in diameter, in the lower branches of trees or in bushes, and they may also inhabit ground nests and burrows.