Simosthenurus

''Simosthenurus'', also referred to as the short-faced kangaroo, is an extinct genus of megafaunal macropods that existed in Australia, specifically Tasmania, during the Pleistocene. Analysis of ''Simosthenurus'' fossils has contributed to the finding that there are three lineages of macropods: Sthenurinae, Macropodinae, and Lagostrophinae. The genus ''Simosthenurus'' was among the sthenurines.

The two most documented members of the genus are ''S. maddocki'' and ''S. occidentalis'', though other species have also been discovered.

Palaeobiology

Osteological information (predominantly cave floor surface finds) has yielded that ''Simosthenurus'' is part of the same family as that of modern kangaroos. However, modern kangaroos are plantigrade hoppers, using jumping as their means of locomotion, while ''Simosthenurus'' was a bipedal unguligrade, walking in a manner similar to that of hominids. Although members of ''Simosthenurus'' were no taller than most modern species of kangaroo, their robust bones, broad pelvis, long arms and short necks were unique adaptations to their browsing mode of feeding. They had single-toed hind feet had small hoof-like nails more typical of animals adapted to moving over relatively flat terrain. ''Simosthenurus'' is a highly distinct lineage of macropods, with no living descendants. However, it is possible that their closest living cousin is the banded hare-wallaby, which is now restricted to small isolated islands off the coast of Western Australia.

S. occidentalis

''S. occidentalis'' mtDNA sequences were obtained from fossils in Tasmanian caves; the fossils yielded radiocarbon dates between 46,000 and 50,000 years ago. The sequences obtained in this study were from fossils much older than any Australian fossils that previously yielded sequences.

The type specimen was collected by E. A. Le Souef and noted in a report to the state's Caves Board, then revised and published by Ludwig Glauert as ''Sthenurus occidentalis'' in 1910. This holotype is fossil material preserving the left and right dentary of an adult found at Mammoth Cave in Southwest Australia.
The specific epithet ''occidentalis'', meaning "of the west", refers to the discovery of this species in Western Australia.

Description

''S. occidentalis'' was a leaf-eating marsupial, about the size of a modern grey kangaroo, though far more robust, with adults estimated to be about 118 kg. The species has been suggested to have used a bipedal striding gait when moving slowly. This is unlike modern kangaroos, which use pentapedal motion, or 'punting', pushing off their tail and forelimbs and swinging their hindlimbs forward when moving slowly. It is thought that, by rearing up on their hind limbs and using their long arms and fingers, they could reach overhead to grasp high leaves and branches and pull them down to their mouth. They then would use their powerful jaws and striated teeth to grind the tough leaves.

A mid-sized species of ''Simosthenurus'', known as 'short-faced' kangaroos, one of several genera in a macropodid lineage that diversified in Pliocene

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