White-bellied woolly mouse opossum

The white-bellied woolly mouse opossum is a small pouchless marsupial of the family Didelphidae. It was formerly assigned to the genus Micoureus, which was made a subgenus of Marmosa in 2009. The specific epithet was given in honour of Constance Sladen, wife of the naturalist Percy Sladen. She funded the 1902 expedition which collected the type specimen.

Description

This is one of the larger mouse opossums, with a head=body length of, a tail in length, and weighing from. The fur is thick and woolly, and is grey over most of the body, fading to buffy-yellow on the head and underparts. There are clear, but narrow, rings of black fur around the eyes. The tail is furred only at the base, and is near black for most of its length, but changes suddenly to pale pink along the last third or so.
The feet are broad, with stout claws and ridges on the underside of the toes that aid in climbing trees. Females do not have a pouch, but have fifteen teats arranged in a circle - more than in any of this species' closest relatives.

Distribution and habitat

The opossum is found across northern Bolivia, in the Brazilian states of Mato Grosso and Mato Grosso do Sul, and in northern Argentina as far south as Tucumán Province. It has also recently been reported from Paraguay. Across this region, it inhabits moist tropical forests, often near the boundary with drier habitats, and has been found from near sea level to montane forests as high as elevation.

Biology and behaviour

The opossum is arboreal, solitary, and nocturnal, spending most of its time in the forest understory. It is omnivorous, feeding on insects and vegetable matter. Little is known of their reproductive biology, but they appear to breed throughout the year, and mothers have been captured with up to seven young attached to their teats.