Tingamarra was discovered in 1987, when a single tooth was found at the Murgon fossil site in south-eastern Queensland.

[1] Tingamarra is believed to be a small (about 20 cm from head to tail) ground-dwelling mammal that ate insects and fruit.

If this interpretation is correct, Tingamarra appears to be the only land-based placental mammal to have arrived to Australia before about 8 million years ago.

The only other native placental mammals in Australia are rodents and dingos (which arrived here more recently), and bats (which presumably flew in).

Woodburne et al.[2] argued that: 1) the true age of Murgon fossil site is the late Oligocene, and 2) that indeed neither shape nor microstructure of the tooth do not allow to distinguish whether Tingamarra was marsupial or placental.