A hopping-mouse is any of about ten different Australian native mice in the genus Notomys. They are rodents, not marsupials, and their ancestors are thought to have arrived from Asia about 5 million years ago.
All are brown or fawn, fading to pale grey or white underneath, have very long tails and, as the common name implies, well-developed hind legs. Around half of the hopping mouse species have become extinct since European colonisation. The primary cause is probably predation from introduced foxes) or cats, coupled with competition for food from introduced rabbits) and cattle.
- Spinifex Hopping Mouse (Notomys alexis)
- The Fawn Hopping Mouse (Notomys cervinus) is found on the sparsely vegetated arid gibber plains and claypans of the Lake Eyre Basin. Small at around 30 to 50 g, and light in colour, it is gregarious and feeds at night on seeds, insects, and green shoots, not needing to drink water. It is classed as vulnerable.
- Some small Dusky Hopping Mouse (Notomys fuscus) populations retain a slender hold on existence in the Strzelecki Desert. They feed, mostly on seeds, at night and shelter in deep vertical burrows.
- Mitchell's Hopping Mouse (Notomys mitchelli)
- Northern Hopping Mouse (Notomys aquilo)
- Long-tailed Hopping Mouse (Notomys longicaudatus)
- The extinct Short-tailed Hopping Mouse (Notomys amplus) was the largest species at around 100 g.
- The extinct Big-eared Hopping Mouse (Notomys macrotis) is known only from two incomplete specimens collected about 100 km north of Perth in the 1840s. It was similar to the Fawn Hopping-mouse of Central Australia but a little larger at around 55 g with a heavier build and longer feet.
- The Darling Downs Hopping Mouse (Notomys mordax) is almost certainly extinct and is known only from a single skull collected somewhere on the Darling Downs of south-east Queensland in the 1840s, apparently from a creature similar to Mitchell's Hopping-mouse. The introduction of cattle to the Darling Downs has greatly changed the ecology of the reigon, and seen several other species exterminated or seriously threatened. (See Paradise Parrot and Yaminon.)
- The Great Hopping Mouse (Notomys sp.) is extinct. It is known only from skulls found in owl pellets in the Flinders Ranges. Some pellets also include bones of the introduced House Mouse—indicating that it survived into historic times, possibly the second half of the 19th century. From the skull, it appears to have been relatively large (perhaps the size of N. amplus or a little more) and to have escaped collection by early 19th century naturalists by chance. From the location of the deposits it is assumed that it preferred clay rather than sandy soils. It is notable that very few of the clay-living hopping mice have survived European settlement, sand dunes apparently providing a more secure refuge from competitors and predators. Some authorities name it the Broad Cheeked Hopping-mouse.