Phalangerids are relatively large, compared with other
possums. The smallest species, the
Sulawesi dwarf cuscus, is cat-sized, averaging in length, while the largest, the
black-spotted cuscus, is around long, and weighs . Besides the large size, other key features distinguishing phalangerids from other possums include the presence of bare skin on at least part of the tail, and low-crowned
molar teeth. They have claws on the fore feet, but none on the hind feet, although these do have an opposable first toe to help grip onto branches. Additionally, in all but one species, both the first and second digits of the fore feet are opposable. Their fur is typically dense or woolly, and may be grey, black, or reddish-brown, often with spots or stripes. Most phalangerids are
folivores, feeding primarily on leaves. Like some similar species, they have a large
cecum to ferment this highly fibrous food and extract as much nutrition as possible. Their teeth, though, are not as highly adapted to this diet as other possums, and they also eat fruit, and even some invertebrates. The only exception to these general rules is the
ground cuscus, which is
carnivorous, and is also less arboreal than other phalangerid species. ==Classification==