Sandhill dunnart

The sandhill dunnart (Sminthopsis psammophila) is a species of carnivorous Australian marsupial of the family Dasyuridae. It is known from four scattered semi-arid areas of Australia: near Lake Amadeus in Northern Territory, the central and eastern Eyre Peninsula in South Australia, the southwestern and western edges of the Great Victoria Desert in Western Australia, and at Yellabinna in South Australia.

The sandhill dunnart is commonly known as a species of "marsupial mouse". The genus name of dunnart was likely derived from the Noongar word "danard". It is the second largest of the 19 dunnart (Sminthopsis) species, with an adult body mass of up to 30 g (1.1 oz) for females and 55 g (1.9 oz) for males. Adults are usually 10 to 16 cm (3.9 to 6.3 in) long. Only the Julia Creek dunnart is larger, weighing 40–70 g (1.4–2.5 oz).

It is identified by its compartively larger size and bicoloured fur patterning (typically grey dorsally and white ventrally). The tail is clearly contrasted (dark ventrally/lighter dorsally) and terminally crested. Its forehead usually has a noticeably dark stripe.

Its thermoneutral body temperature is around 34.4 °C (93.9 °F). While the sandhill dunnart's physiology resembles that of other dunnarts, penile morphology and molecular biology suggest that it is basal to its genus.

The sandhill dunnart usually moves by running smoothly on all four legs, sometimes with sudden short stops, during which they often squat with the forebody slightly elevated.^{[citation needed]} The maximum speed recorded for S. psammophila is 3 km/h (1.9 mph).

The species prefers to eat invertebrate prey, such as ants, beetles, spiders, grasshoppers, termites, wasps and centipedes. In the Western Great Victoria Desert, the sandhill dunnart has an ant-rich diet, commonly consuming Camponotus spp. (sugar ants) and Iridomyrmex spp. (meat ants). However, dunnarts are thought to be a generalist feeders and extremely opportunistic. Other recorded prey species are gastropods, geckos, skinks and mice. Food intake remains high in all seasons, varying only slightly in proportion.

In severe conditions when food is scarce, the sandhill dunnart enters short and shallow periods of torpor. The species' documented states of mental and physical inactivity helps it to conserve water and energy. From an analysis of the sandhill dunnart's metabolic, thermal, and ventilatory physiology, the organism's body temperature ranges, including thermoneutral, thermolability below thermoneutral, and mild hyperthermia temperatures are typical of those seen in small dunnarts and dasyurids.

Sandhill dunnarts typically begin breeding in September, with offspring born from September to October. Pouch young, dependent young and weaned juveniles are present in October. However, juveniles have been trapped between October and April. This information may suggest that with the right conditions in a good season, sandhill dunnarts may be able to produce another litter. There is a sixteen- to nineteen-day interval between mating and birth.