Fawn hopping mouse

The fawn hopping mouse (Notomys cervinus) is a medium sized rodent endemic to the Channel Country Bioregion of northeast South Australia and southwest Queensland in Australia. They inhabit open gibber (stony) and clay plains of the Lake Eyre basin. While the population and distribution has been greatly reduced since European settlement, the current population shows little evidence of significant decline and is consequently listed as 'Near Threatened'.

The first description of this species was published by John Gould from a holotype of unknown collection location from Victoria. It was presented to the Zoological Society of London and published in 1853. The description was aided by several paratype specimens also from an unspecified location and donation. It was determined to be segregated by habitat from the dusky hopping mouse (Notomys fuscus) and identifiable by lacking throat pouches. Also by the males having a naked area of glandular skin.

The fawn hopping mouse is a medium sized rodent weighing between 30 and 50 g (1.1 and 1.8 oz) with a head and body length between 10 and 12 cm (3.7 to 4.7 in). Its bi-coloured tail is longer than the length of the body reaching a length of 12–16 cm (4.7 to 6.3 in) ending with a tuft of dark hairs. The head is broad and short with large, long ears with distinctive large protuberant eyes. Whiskers on the muzzle are extremely long reaching a length of up to 6.5 cm (2.6 in). The hind legs and feet are very elongated similar to other hopping mouse species. This allows for efficient movements through the environment.

The colour range of the upper body between individuals varies from a pale pinkish-fawn to grey. The underside is white with the tail following a similar colour pattern to the rest of the body except the dark brush at the tip. The absence of throat pouches in both males and females can be used to distinguish fawn hopping mouse from the closely related species the dusky hopping mouse (Notomys fuscus) and spinifex hopping mouse (Notomys alexis). The presence of a naked area of glandular skin on the chest between the forelimbs of males (and some females) can also be used to distinguish between species.

The current endemic range of the fawn hopping mouse is largely reduced to the Channel Country Bioregion north-east South Australia and south-west Queensland. Restricted to a quarter of the area surrounding the Lake Eyre Basin with a patchy distribution. Records from the 19th century and anecdotal evidence from the 1930s show that the former range of this species was much larger and suggests it may have existed in a broader range of habitats. The historical range included  most of the Lake Eyre Basin, southern Northern Territory, and the eastern edge of the Nullarbor Plain as well as western New South Wales. Subfossil evidence supports this broader range along with some specimens have been found in Western Australia around the Nullarbor Plain.

The species is currently listed as extinct in NSW and the Northern Territory. Insubstantial evidence for the species has been found in Charlotte Waters, Alice Springs, Uluṟu-Kata Tjuṯa National Park and Curtin Springs. Targeted surveys conducted in 2008 and 2009 in the south-eastern Northern Territory failed to locate the species leading to it being declared extinct. From known pre-European range, the overall decline of the species is higher than 50% since the 1950s.

The preferred habitat of the fawn hopping mouse is open gibber and clay plains in arid environments. These are smaller areas of overlying sand with sparse vegetation. Small ephemeral grasses and forbs dominate these environments with the occasional taller perennial plant.

The fawn hopping mouse constructs burrows in sand patches, or in gibber or claypans when soil is softened after rain. These are simpler and shallower than the ones constructed by dusky hopping mouse up to a metre deep and have between one and three entrances. One individual will have at least two burrows in the system. Fawn hopping mice can be either solitary or live in small groups made up of two to four individuals. This species is nocturnal, using its burrows during the day to avoid the highest extreme temperatures.