The Tasmanian pygmy possum (''Cercartetus lepidus''), also known as the little pygmy possum or tiny pygmy possum, is the world's smallest
possum. It was first described by
Oldfield Thomas in 1888, after he identified that a museum specimen labelled as an
eastern pygmy possum
The eastern pygmy possum (''Cercartetus nanus'') is a diprotodont marsupial of south-eastern Australia. Occurring from southern Queensland to eastern South Australia and also Tasmania, it is found in a range of habitats, including rainforest, s ...
in fact represented a species then unknown to science. The
holotype
A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ...
resides in the
Natural History Museum
A natural history museum or museum of natural history is a scientific institution with natural history collections that include current and historical records of animals, plants, fungi, ecosystems, geology, paleontology, climatology, and more. ...
in London.
Description
Although it is a marsupial, the Tasmanian pygmy possum superficially resembles a
dormouse
A dormouse is a rodent of the family Gliridae (this family is also variously called Myoxidae or Muscardinidae by different taxonomists). Dormice are nocturnal animals found in Africa, Asia, and Europe. They are named for their long, dormant hibe ...
, and it is the smallest of all the known species of
possum.
[ Adults range from in head-body length, with a tail, and weigh just .] Their fur is soft and thick, and is fawn in colour over most of the body, fading to a pale grey on the underparts.[
The snout is short with long ]whisker
Vibrissae (; singular: vibrissa; ), more generally called Whiskers, are a type of stiff, functional hair used by mammals to sense their environment. These hairs are finely specialised for this purpose, whereas other types of hair are coarser ...
s, and the eyes are directed forwards and surrounded by slightly darker fur, although without the conspicuous black rings seen on other pygmy possums. The ears are mobile and largely hairless. The tail is prehensile
Prehensility is the quality of an appendage or organ that has adapted for grasping or holding. The word is derived from the Latin term ''prehendere'', meaning "to grasp". The ability to grasp is likely derived from a number of different orig ...
, and thickly furred at the base, which may be widened by fat stores beneath the skin. The remainder of the tail is relatively narrow and cylindrical, with only sparse hair between numerous tiny scales
Scale or scales may refer to:
Mathematics
* Scale (descriptive set theory), an object defined on a set of points
* Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original
* Scale factor, a number w ...
.[
]
Distribution and habitat
The Tasmanian pygmy possum is found throughout Tasmania
)
, nickname =
, image_map = Tasmania in Australia.svg
, map_caption = Location of Tasmania in AustraliaCoordinates:
, subdivision_type = Country
, subdi ...
, but was at one time thought to be extinct elsewhere. In 1964, a living animal was discovered on Kangaroo Island
Kangaroo Island, also known as Karta Pintingga (literally 'Island of the Dead' in the language of the Kaurna people), is Australia's third-largest island, after Tasmania and Melville Island. It lies in the state of South Australia, southwest ...
in South Australia
South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...
, and further populations have since been discovered in the Murray-Darling basin in South Australia
South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...
and Victoria
Victoria most commonly refers to:
* Victoria (Australia), a state of the Commonwealth of Australia
* Victoria, British Columbia, provincial capital of British Columbia, Canada
* Victoria (mythology), Roman goddess of Victory
* Victoria, Seychelle ...
.[ There are no formally recognised subspecies, although it has been proposed, based on genetic information, that the mainland and Tasmanian populations may be subspecies, or even entirely separate species.] They inhabit sclerophyll
Sclerophyll is a type of vegetation that is adapted to long periods of dryness and heat. The plants feature hard leaves, short internodes (the distance between leaves along the stem) and leaf orientation which is parallel or oblique to direct ...
forest, mallee, and open heathland
A heath () is a shrubland habitat found mainly on free-draining infertile, acidic soils and characterised by open, low-growing woody vegetation. Moorland is generally related to high-ground heaths with—especially in Great Britain—a coole ...
vegetation.
The oldest fossils for this species date from the late Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...
, and were found on the mainland, with the oldest known Tasmanian fossils being much younger. Fossils have been found as far afield as eastern Victoria and New South Wales
)
, nickname =
, image_map = New South Wales in Australia.svg
, map_caption = Location of New South Wales in AustraliaCoordinates:
, subdivision_type = Country
, subdivision_name = Australia
, established_title = Before federation
, es ...
, suggesting that the species was once much more widespread than it is today.[
It had been feared that the Kangaroo Island population may have been wiped out by the 2019 bushfires that burnt almost half the island. But in late 2020, conservation group Kangaroo Island Land for Wildlife recorded live pygmy possums in a fauna survey of unburnt forest.]
Behaviour
The Tasmanian pygmy possum is nocturnal and 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, but others are exclusively arboreal. The habitats pose nu ...
. It lives primarily in shrubland or forest undergrowth, and, although a good climber, rarely ventures into the higher branches of trees, presumably because this would make it more vulnerable to avian predators. Pygmy possums use strips of bark to construct dome-like nests in tree cavities or rotten wood, but are solitary animals that do not share their nests with other individuals except for their own young.[
]
Biology
Tasmanian pygmy possums are omnivorous, feeding on insects, spiders, small lizards, nectar, and pollen, the latter two primarily coming from ''Banksia
''Banksia'' is a genus of around 170 species in the plant family Proteaceae. These Australian wildflowers and popular garden plants are easily recognised by their characteristic flower spikes, and fruiting "cones" and heads. ''Banksias'' range ...
'' and eucalypt
Eucalypt is a descriptive name for woody plants with capsule fruiting bodies belonging to seven closely related genera (of the tribe Eucalypteae) found across Australasia:
''Eucalyptus'', ''Corymbia'', ''Angophora'', '' Stockwellia'', ''Allosyn ...
s. Their preference for eating pollen without destroying the host flower may mean that they help to pollinate
Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds, most often by an animal or by wind. Pollinating agents can be animals such as insects, birds, a ...
some species of plant. Known predators include Tasmanian devils, quoll
Quolls (; genus ''Dasyurus'') are carnivorous marsupials native to Australia and New Guinea. They are primarily nocturnal and spend most of the day in a den. Of the six species of quoll, four are found in Australia and two in New Guinea. Anoth ...
s, kookaburra
Kookaburras are terrestrial tree kingfishers of the genus ''Dacelo'' native to Australia and New Guinea, which grow to between in length and weigh around . The name is a loanword from Wiradjuri ''guuguubarra'', onomatopoeic of its call. The ...
, masked owls, and tiger snakes.[
During cold weather, especially below about 6 °C (43 °F), Tasmanian pygmy possums have the ability to enter ]torpor
Torpor is a state of decreased physiological activity in an animal, usually marked by a reduced body temperature and metabolic rate. Torpor enables animals to survive periods of reduced food availability. The term "torpor" can refer to the time ...
. While in this state, body temperature drops, and oxygen consumption falls to just 1% of normal.
Breeding occurs throughout the year, although it may be more common in spring and summer. The female has a well-developed pouch containing four teat
A teat is the projection from the mammary glands of mammals from which milk flows or is ejected for the purpose of feeding young. In many mammals the teat projects from the udder. The number of teats varies by mammalian species and often corr ...
s, which therefore limits the maximum size of a litter to this number. The young leave the pouch at around 42 days, although they may cling to the mother's fur and be carried about after this age. They leave the nest to fend for themselves at around 90 days of age.[
]
References
External links
Factsheet on the little pygmy possum from Tasmanian Department of Primary Industries and Water
*[https://web.archive.org/web/20070623152824/http://museumvictoria.com.au/bioinformatics/mammals/images/thumblmar.htm Images: Australian mammal images (including ''C. lepidus'') on Museum Victoria website]
Information and Image at Animal Diversity Web
{{Taxonbar, from=Q209598
Mammals of Tasmania
Possums
Mammals of South Australia
Mammals of Victoria (Australia)
Marsupials of Australia
Mammals described in 1888
Taxa named by Oldfield Thomas