The Slender-tailed Dunnart (Smithopsis murina), also known as the Common Dunnart in Australia, is a dasyurid marsupial closely related to the Tasmanian Devil. The Slender-tailed Dunnart is native to the east and south-east coast and interior of Australia, from the Cape York Peninsula to the Port Lincoln area of South Australia. There a 2 subspecies: S. m. murina is found throughout the distribution, and S. mu. tatei found between Townsville and Cairns in Queensland. This species is found at altitudes of between 197 to 1180 feet and prefers habitats with an average rainfall between 11.8-33.5 inches per year. Habitats encountered include Mallee scrub, dry forests and woodlands and dry heath, these areas have sparse ground and shrub cover but have dense leaf and bark litter in Victoria to rainforest edges and swamps in Queensland.
It has an average body length of 2.8 to 4.7 inches with a tail length of 2.2 to 5.1 inches. Males weigh up to 1.5 ounces while females are much smaller. It has a preference for beetles and moths. Other prey is taken in less often unless its main source is unavailable.
The Slender-tailed Dunnart’s breeding season begins in New South Wales between September and March each year, with the female breeding again after weaning the first offspring. The female may live to breed a second year, although the male generally dies after mating. Gestation is for 12.5 days with weaning at 60-65 days and the litter size is usually 8-10 joeys. The species is nocturnal.