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Plains Mouse

Pseudomys australis

French: Pseudomys de Gray / German: Sidliche Australienmaus / Spanish: Raton de llanura

Other common names: Plains Pseudomys, Plains Rat

Taxonomy. Pseudomys australis Gray, 1832,

south-west side of Liverpool Plains, New South Wales, Australia.

Pseudomys australis is the type species of the genus. An investigation in 1999 found that P. australis contains geographically well-separated populations that have high levels of allozyme heterozygosity but no evidence of speciation. It was found to be close to P. fieldi and P. higginsi by F. Ford in 2006 and B. Breed and Ford in H. |.

McLennan and colleagues’ 2017 study, while a recent phylogeny by P. Smissen and K. C. Rowe in 2017 grouped it in a clade with Mastacomys fuscus and P. desertor . Further work is needed in orderto refine the phylogeny of the Pseudomys complex. Monotypic.

Distribution. SC Australia.

Descriptive notes. Head-body 90-145 mm, tail 85-125 mm, ear 20-25 mm, hindfoot 24-31 mm; weight 30-65 g. The Plains Mouse has a hairy tail nearly equal to headbody length, being gray above and white below. Dorsal pelage is gray to gray brown, and the undersurface is white.

Habitat. Cracked clay soils in depressions or minor drainage lines and in arid stony desert and gibber plains.

Food and Feeding. Diet is composed of seeds, green plants, and insects.

Breeding. Plains Mice are probably polygamous or promiscuous; burrows during breeding periods are occupied by one male and one to three females. Breeding is continuous in captivity, but in the wild it seems to be highly dependent on rain. Gestation lasts 30-31 days; female gives birth to 1-4 young in the wild; up to seven have been recorded in captivity, although only fourlikely survive as female has only fournipples for suckling pups. Young are weaned at around one month of age.

Activity patterns. The Plains Mouse is nocturnal and terrestrial, and makes shallow burrows.

Movements, Home range and Social organization. Plains Mice seem sometimes to live in colonies of, at least in good times, up to 20 individuals. A study found home range sizes of up to 1-6 ha.This species contracts back to refuge sites during dry times.

Status and Conservation. Classified as Vulnerable on The IUCN Red List. Irregular population outbreaks are known for this species, whose distribution is very fragmented. Overgrazing by cattle and predation by introduced mammalian carnivores are major threats. The Plains Mouse has recently been discovered in The Conservation Paddock at Fowlers Gap Research Station in western New South Wales and also occurs in the Arid Recovery Reserve at Roxby Downs in northern South Australia.

Bibliography. Brandle & Moseby (1999), Brandle & Pavey (2008), Brandle et al. (1999), Breed & Ford (2007), Ford (2006), Menkhorst (1995), Pavey, Cole et al. (2014), Pavey, Jefferys et al. (2016), Watts & Aslin (1981).