The ground cuscus (''Phalanger gymnotis'') is a
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 ...
from the order
Diprotodontia
Diprotodontia (, from Greek language, Greek "two forward teeth") is the largest extant order (biology), order of marsupials, with about 155 species, including the kangaroos, Wallaby, wallabies, Phalangeriformes, possums, koala, wombats, and many ...
and belongs within the family
Phalangeridae, a diverse family consisting of the other
cuscus species and the
brushtail possums (''
Trichosurus'' spp.) and the
scaly-tailed possum (''Wyulda squamicaudata'').
Names
It is known as madaw, ket-ketm, or kñm in the
Kalam language of
Papua New Guinea
Papua New Guinea, officially the Independent State of Papua New Guinea, is an island country in Oceania that comprises the eastern half of the island of New Guinea and offshore islands in Melanesia, a region of the southwestern Pacific Ocean n ...
.
[Pawley, Andrew and Ralph Bulmer. 2011. ''A Dictionary of Kalam with Ethnographic Notes''. Canberra. Pacific Linguistics.]
Description
Body weight of the ground cuscus averages . Head and body length is about and tail length is although wild populations show variation depending on their location, with individuals from lowland regions being the largest and highland animals the smallest. It has opposable thumbs on the hind feet, a
prehensile tail, and a bifurcation between the second and third front digits to allow it to move easily within the trees and to feed in a suspensory position.
The pelage is short and dense and is usually some shade of grey, often with white markings on the belly and scrotum. The tail has a course,
tubercle-like appearance at the base and on the dorsal side, with a ridged fingertip patterning on the underside to facilitate gripping. The feet are large with five digits, only the opposable digit on each hind foot is without claws. The ears of the ground cuscus are prominent and naked. The pouch opens forward and contains four
mammae.
Behavior
Cuscuses are generally
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 ...
folivore/
frugivores, and are slow-moving 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 ...
, although hunters in
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...
have observed them sunning themselves outside their burrows in the early morning. The tendency to nest in burrows makes this species vulnerable to hunting with dogs.
The ground cuscus differs from all other
phalangerids in spending its days in burrows in the ground and appears as comfortable at ground level as in the trees. Captive specimens are often described as being mainly arboreal, whereas wild ground cuscuses are generally described as a terrestrial species. Regarded as a solitary species, the ground cuscus fights by adopting a bipedal stance and lashing out with the forelimbs whilst emitting hissing and barking vocalisations. In captivity, compatible pairs can be housed together, but periodic fighting may still occur.
Lifespan
No information on longevity in the wild is available. A captive specimen was known to live for 18 years with 10 years not uncommon.
Habitats
The ground cuscus is endemic to New Guinea and
Aru Islands and inhabits both forests and scrubland. It is most common at elevations between but has been recorded as low as and as high as . Swampy areas, deltas and floodplains are usually avoided. The ground cuscus is classified as "Least Concern" on the
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...
, although it has been
extirpated
Local extinction, also extirpation, is the termination of a species (or other taxon) in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions.
Local extinctions mark a chan ...
from parts of its original range by excessive hunting.
References
{{Taxonbar, from=Q209134
Possums
Mammals described in 1875
Taxa named by Wilhelm Peters
Taxonomy articles created by Polbot
Marsupials of New Guinea
Taxa named by Giacomo Doria