Description: Procoptodon goliah was the largest of the Pleistocene sthenurine kangaroos, weighing up to 200kg, or about double the size of a modern-day red kangaroo.

The sthenurines were a family of short-faced kangaroos which became numerous about 2 million years ago. Fourteen species are now extinct, with a single related species (the banded hare-wallaby), surviving on two islands off the coast of Western Australia. The extinct sthenurines varied in size from quite small animals the size of a wallaby to giants like Procoptodon goliah. All had a single long toe with a hoof-like claw on their hind foot, a short, thick tail and long arms. Most characteristic of all, the sthenurines had short, broad faces with an expanded nasal area that may have been used for amplifying sound.

The short face and deep skull reflect the powerful mechanical advantage they provide to the chewing muscles. Procoptodon was undoubtedly capable of eating very tough leaves and stems. Because of its bulk it probably moved fairly slowly, although the mechanics of its hind limbs indicate that it was capable of rather large hops. Animals that hop upright are generally found in areas with a denser understory, as they are able to see over the top of it.

Balancing on its single, hoof-like hind toes and propped up by its tail, Procoptodon could have reached leaves more than 3 metres above the ground. Only the sthenurine kangaroos were capable of reaching above their head in this manner—Procoptodon represents the most extreme adaptation of the extinct sthenurines.

Distribution: Procoptodon flourished over much of Australia until its extinction around 40,000 years ago.

Fossils: Procoptodon fossils have been found at the Naracoorte World Heritage fossil deposits in South Australia, Lake Menindee in New South Wales, Darling Downs in Queensland, and at many other sites.