Fossil remains in eastern New South Wales indicate that the range of C. lepidus was condensing southward before the first Europeans arrived (Burton, 1987). Since then, most of the forest has been cleared, destroying the little pygmy-possum's habitat. Cercartetus lepidus is also referred to as tasmanian pygmy-possum (Green, 1983).
Perception Channels: tactile ; chemical
Cercartetus lepidus is widespread through northwestern Victoria and also present in a number of conservation reserves. The status of the little pygmy-possum should be secure as long as there are not any major change in land-use on public land or to fire regimes. Cercartetus lepidus can survive fire, but the long-term effects are not yet known (Menkhorst, 1995). Extensive forest clearing has removed much of the habitat of C. lepidus on the mainland, yet sufficient habitat is still left in Tasmania. The woodchip industry might also play a role in the future of the Little Pygmy-possum (Green, 1983).
IUCN Red List of Threatened Species: least concern
Cercartetus lepidus is omnivorous. It feeds on nectar and pollen from a variety of flowering plants. For example, Banksia ornata, Eucalyptus spp., Leptospermum coriaceum, and Astroloma conostephioides pollen have all been found in faecal and gut samples of this mammal. Sugar-water, honey, and apple are also a part of the diet (Ward, 1992). Little pygmy-possums also prey on a wide range of invertebrates including spiders, scorpions, and insect larvae. Small lizards are also included in their diet. The little pygmy-possum secures the prey with its forepaws and tears away portions with its teeth. Daily food consumption is about 7% of its body weight (Collins, 1973).
Animal Foods: insects; terrestrial non-insect arthropods
Plant Foods: fruit; nectar; pollen
Primary Diet: omnivore
The little pygmy-possum is found in Southeastern Australia from the mallee heathlands of Victoria to the forests of Tasmania. Cercartetus lepidus individuals have also been found on Kangaroo Island. (Burton, 1987)
Biogeographic Regions: australian (Native )
Even though Cercartetus lepidus has a prehensile tail and is an excellent climber, it normally lives close to the ground and stays away from the higher branches of trees. This may abe due to predation by owls (Green, 1983). In Tasmania, C. lepidus is found in tall closed forest to low woodland, in areas with an average rainfall of 300 mm. In mainland Australia and Kangaroo Island, C. lepidus is found from low open woodland to heathlands. The heathlands of Victoria, with an average rainfall of 1200 mm, provide a greater range of food that favors the continous breeding pattern previously mentioned (Ward, 1992).
Habitat Regions: temperate ; tropical ; terrestrial
Terrestrial Biomes: forest ; scrub forest
Cercartetus lepidus is the smallest of the living diprotodont marsupials. The head and body length ranges from 50-65 mm, with the tail length ranging from 60-75 mm. The litte pygmy-possum fur is soft with a pale fawn color on its dorsal side and a grey belly. Both the small size and grey belly of C. lepidus distinguishes it from other members of the family. Cercartetus lepidus teeth have low, rounded cusps associated with their diet of soft foods. However, one of the premolars on each side is usually blade-like or plagiaulacoid (Green, 1983).
Cercartetus lepidus is syndactylous and has an opposable hallux on its hind feet. Other characteristics include a conical head with short muzzle, large eyes, and short, rounded ears (Myers, 1997). No sexual dimorphism is been seen in body size and/or weight (Ward, 1992).
Other Physical Features: endothermic ; bilateral symmetry
Female C. lepidus have four teats in their pouch, which limits their litter size to four. Females are polyestrous and can probably rear more than one litter per year (Menkhorst, 1995). Little pygmy-possums found in Victoria have been seen to lactate in January, February, April, June, and September, indicating that breeding occurs throughout the year. However, in Tasmania, lactating females have only been seen between September and January; there, breeding is confined to spring and summer (Ward, 1992). Young are weaned at approximately 50 days. Once the young are half grown and too large for the pouch, they are left in the nest while their mom finds food. If the young must be transported, they cling to their mother's back. Cercartetus lepidus reaches maturity at about 3 months (Green, 1983).
Male C. lepidus have been found with regressed testes and testes that are smaller than normal, suggesting that males may not be reproductively active throughout the year (Ward, 1992).
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
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 in fact represented a species then unknown to science. The holotype resides in the Natural History Museum in London.[3]
Although it is a marsupial, the Tasmanian pygmy possum superficially resembles a dormouse, and it is the smallest of all the known species of possum.[3] Adults range from 6.6 to 7.5 centimetres (2.6 to 3.0 in) in head-body length, with a 6 to 7.2 centimetres (2.4 to 2.8 in) tail, and weigh just 7 to 10 grams (0.25 to 0.35 oz).[4] Their fur is soft and thick, and is fawn in colour over most of the body, fading to a pale grey on the underparts.[3]
The snout is short with long whiskers, 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, 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.[3]
The Tasmanian pygmy possum is found throughout Tasmania, but was at one time thought to be extinct elsewhere. In 1964, a living animal was discovered on Kangaroo Island in South Australia, and further populations have since been discovered in the Murray-Darling basin in South Australia and Victoria.[3] 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.[5] They inhabit sclerophyll forest, mallee, and open heathland vegetation.[2]
The oldest fossils for this species date from the late Pleistocene, 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, suggesting that the species was once much more widespread than it is today.[3]
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.[6]
The Tasmanian pygmy possum is nocturnal and arboreal. 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.[3]
Tasmanian pygmy possums are omnivorous, feeding on insects, spiders, small lizards, nectar, and pollen, the latter two primarily coming from Banksia and eucalypts. Their preference for eating pollen without destroying the host flower may mean that they help to pollinate some species of plant. Known predators include Tasmanian devils, quolls, kookaburra, masked owls, and tiger snakes.[3]
During cold weather, especially below about 6 °C (43 °F), Tasmanian pygmy possums have the ability to enter torpor. While in this state, body temperature drops, and oxygen consumption falls to just 1% of normal.[7]
Breeding occurs throughout the year, although it may be more common in spring and summer. The female has a well-developed pouch containing four teats, 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.[3]
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 in fact represented a species then unknown to science. The holotype resides in the Natural History Museum in London.