Notoryctidae

The notorycteromorphs (Notoryctidae) are an extant family of notoricteromorphic australidelfian marsupials that includes a single genus, Notoryctes , with two species. They are commonly known as marsupial moles. They live in the Australian desert. They spend most of their time underground and rarely come to the surface.

Notorichthids live in the sandy regions of south-central and north-eastern Australia and are closely reminiscent of European moles, having the same dimensions and the same adaptations for burrowing and underground life.

Indeed, they have two very long claws on their front legs that are used for digging, underdeveloped eyes hidden by their hair, and a horny plate on their snout that serves as a drill.

They do not dig permanent tunnels, only small galleries a few centimeters from the surface,

Distribution

Both extant species inhabit the sandy deserts of the western half of Australia.

Phaneroptics and anatomy

The body is the size of a placental mole, flattened and with a highly developed locomotor system. It is covered in abundant silky hair that varies from white to golden. Sometimes if the land where they live is rich in iron, the hair can turn reddish due to this metal.

It is a characteristic of this family to have the last five cervical vertebrae fused, which gives the body rigidity in such a way that it can develop more power pushing the sand with its head during the excavation.

The head is large and robust. The muzzle is covered by a bare horny protrusion. The eyes are covered by skin, measure less than one mm in diameter, and are underdeveloped in such a way that they are barely functional. On each side of the head there is a hole as the only rest of the ears.

The teeth are degenerated and the dental formula varies from one specimen to another. An average formula would be composed as indicated in the attached table.

The upper molars are zalambdodont, and the lower ones have lost the talonid socket. They cannot be considered to be properly diprotodonts or polyprotodonts.

The extremities are powerful, especially the front ones, whose third and fourth fingers are endowed with extremely powerful triangular section nails. Unlike other Australian marsupials, there are no syndactyly phenomena and each limb has five fingers.

The tail is short, cylindrical, and furrowed with rings. It is covered by a thick leather-like skin. It can measure up to 2.5 cm and seems to be endowed with great tactile sensitivity.

Nutrition and eating habits

This species feeds on all kinds of terrestrial invertebrates that it captures both on the surface and underground, in an incessant coming and going.

Biology of reproduction

The reproductive physiology of this species is not well known. The gestation, lactation, or life expectancy periods of this species have not been described.

Males do not have a scrotum, the testicles are found between the skin and the abdominal cavity.

Females have a small but well-developed pouch, open at the back to maintain hygiene during digging. Inside, two nipples are used to nurse the young that are born around the month of November in number from 1 to 2 per litter.

Behavior

These species move under the desert sand as if they were diving, pushing with their heads and pushing the sand away with their hands. The paths that it remains under the sand are not excessively long, moving along the surface with the help of its hind limbs, leaving a characteristic track made up of three points that correspond to both hind limbs and the tail.

Conservation status

The only two living species of marsupial moles are listed by the IUCN as threatened (EN).