The Giant Rabbit is a mystery marsupial creature, reported from deserts of Central Australia. Gold prospectors are said to have reported rabbits 9 feet long, according to Bernard Heuvelmans.
- Naturalist Ambrose Pratt suggested a surviving Diprotodon optatum, the largest marsupial that ever lived, which was probably contemporaneous with earlier generations of Aborigines and died out 18,000–6,000 years ago. This large-snouted browser was nearly 10 feet long and almost 8 feet high at the shoulder.
- Palorchestes azael, a Late Pleistocene herbivore, was a 1-ton marsupial the size of a horse that could balance on its powerful tail and hind limbs like a kangaroo while reaching up with huge, curved claws on its forelimbs to pull trees and branches into the reach of its short, elephant-like trunk.
- Christine Janis pointed out that the Sthenurinae, an extinct subfamily of kangaroos, may be better candidates than the lumbering Diprotodon optatum. The sthenurine kangaroos had shorter tails, bigger forearms, and possibly longer ears, making them look more rabbit-like.