Simosthenurus occidentalis
| Simosthenurus occidentalis | |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Infraclass: | Marsupialia |
| Order: | Diprotodontia |
| Family: | Macropodidae |
| Genus: | †Simosthenurus |
| Species: | †S. occidentalis
|
| Binomial name | |
| †Simosthenurus occidentalis | |
Simosthenurus occidentalis is a species of sthenurine marsupial that existed in Australia during the Pliocene, becoming extinct in the Pleistocene epoch around 42 000 years ago. A large herbivorous biped, it is comparable in form to the modern macropods, although considerably larger, and is referred to as a short-faced kangaroo.
Taxonomy
The type specimen was collected by E. A. Le Souef and noted in a report to the 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.[1] The specific epithet occidentalis, meaning "of the west", refers to the discovery of this species in Western Australia.[2]
Description
A mid-sized species of Simosthenurus, known as 'short-faced' kangaroos, one of several genera in a macropodid lineage that diversified in Pliocene Australia. The mass of adults is estimated to have around 118 kilograms. The dentition contains molars set close to the jaw, which combined with the cranial structure, strongly indicates an animal capable of consuming tough vegetation. The short jaw and facial anatomy clearly distinguishes their appearance from the surviving lineage of kangaroos, which usually graze on grasses rather than browsing for tougher vegetation, and more closely resembles another browsing marsupial, the modern koala. Modelling of the bite force and the skulls resistance to torsional forces, the result of twisting and tearing bark or branches, suggests that the species was able to consume material other than the tough leaves favoured by koalas. A set of powerful molars are located close to the hinge of jaw, further back than a koala, improving the mechanical advantage and reducing the hazard of dislocation while browsing.[3]
Distribution and habitat
The species is represented in the records of many southern fossil sites in Australia, including Tasmania. The type locality is located in Southwest Australia, at Mammoth Cave, and evidence from another site in the southwest indicates it existed until about 42 000 years ago.[3] Fossils assigned to the species have been obtained at sites in the Southwest, southern regions of Central Australia and the southeast of the continent. In Tasmania S. occidentalis has been identified at fossil sites in the northeast and central regions, the species has also been found at the nearby King Island.[2]
Their distribution in the Pleistocene is dated to late-middle to late deposits.[2]
References
- ^ a b Glauert, L. (1910). "The Mammoth Cave". Records of the Western Australian Museum. 1. Western Australian Museum,: 11–36.
{{cite journal}}: CS1 maint: extra punctuation (link) - ^ a b c Prideaux, G.J. (2004). Systematics and evolution of the sthenurine kangaroo. University of California Press. ISBN 0-520-09845-5.
- ^ a b Mitchell, D.R.; Evans, A.R. (11 September 2019). "The anatomy of a crushing bite: The specialised cranial mechanics of a giant extinct kangaroo". PLOS ONE. 14 (9): e0221287. doi:10.1371/journal.pone.0221287.
{{cite journal}}: CS1 maint: unflagged free DOI (link)