The white-bellied woolly mouse opossum (''Marmosa constantiae'') is a small pouchless

marsupial Marsupials are a diverse group of mammals belonging to the infraclass Marsupialia. They are natively found in Australasia, Wallacea, and the Americas. One of marsupials' unique features is their reproductive strategy: the young are born in a r ...

of the family Didelphidae. It was formerly assigned to the genus '' Micoureus'', which was made a subgenus of ''

Marmosa The 27 species in the genus ''Marmosa'' are relatively small Neotropical members of the family Didelphidae. This genus is one of three that are known as mouse opossums. The others are '' Thylamys'' (the "fat-tailed mouse opossums") and '' Tlacu ...

'' in 2009. The specific epithet was given in honour of

Constance Sladen Constance Sladen (11 August 184817 January 1906) was an artist, architectural historian and philanthropist who was one of the first female members of the Linnean Society of London and founded the Percy Sladen Memorial Trust in memory of her la ...

(née Anderson), 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 Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...

, in the

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

ian states of

Mato Grosso Mato Grosso ( – ) is one of the states of Brazil, the List of Brazilian states by area, third largest by area, located in the Central-West Region, Brazil, Central-West region. The state has 1.66% of the Brazilian population and is responsible ...

and

Mato Grosso do Sul Mato Grosso do Sul ( ) is one of Federative units of Brazil, Brazil's 27 federal units, located in the southern part of the Central-West Region, Brazil, Central-West Region, bordering five Brazilian states: Mato Grosso (to the north), Goiás and ...

, and in northern

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

as far south as

Tucumán Province Tucumán () is the most densely populated, and the second-smallest by land area, of the provinces of Argentina. Located in the northwest of the country, the province has the capital of San Miguel de Tucumán, often shortened to Tucumán. Neighb ...

. It has also recently been reported from

Paraguay Paraguay, officially the Republic of Paraguay, is a landlocked country in South America. It is bordered by Argentina to the Argentina–Paraguay border, south and southwest, Brazil to the Brazil–Paraguay border, east and northeast, and Boli ...

. 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 Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally (scansorial), but others are exclusively arboreal. The hab ...

, solitary, and

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

, spending most of its time in the forest understory. It is omnivorous, feeding on insects (especially bugs) 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.

References

{{Taxonbar, from=Q194449 Opossums Marsupials of Argentina Marsupials of Bolivia Marsupials of Brazil Mammals of Paraguay Mammals described in 1904 Taxa named by Oldfield Thomas