Vombatiformes Temporal range: | |
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Phascolarctos cinereus | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Infraclass: | Marsupialia |
Order: | Diprotodontia |
Suborder: | Vombatiformes Burnett, 1830 |
Families | |
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The Vombatiformes are one of the three suborders of the large marsupial order Diprotodontia. Seven of the nine known families within this suborder are extinct; only the families Phascolarctidae, with the koala, and Vombatidae, with three extant species of wombat, survive.
Among the extinct families are the Diprotodontidae, which includes the rhinoceros sized Diprotodon , believed to be the largest marsupials ever, as well as the "marsupial lions" Thylacoleonidae and "marsupial tapirs" Palorchestidae.
Suborder Vombatiformes
Diprotodon is an extinct genus of marsupial from the Pleistocene of Australia, containing one species, D. optatum. The earliest finds date to 1.77 million to 780,000 years ago, but most specimens are dated to after 110,000 years ago. Its massive fossils were first unearthed in 1830 in Wellington Caves, New South Wales, before any serious scientists were active on the continent, and were variably guessed to belong to rhinos, elephants, hippos, or dugongs. Diprotodon, formally described by English naturalist Richard Owen in 1838, was the first named Australian fossil mammal, and set Owen on a path to becoming the foremost authority of his time on other marsupials and Australian megafauna so enigmatic to European science.
Diprotodontia is the largest extant order of marsupials, with about 155 species, including the kangaroos, wallabies, possums, koala, wombats, and many others. Extinct diprotodonts include the hippopotamus-sized Diprotodon, and Thylacoleo, the so-called "marsupial lion".
The Phascolarctidae is a family of marsupials of the order Diprotodontia, consisting of only one extant species, the koala, and six well-known fossil species, with another five less well known fossil species, and two fossil species of the genus Koobor, whose taxonomy is debatable but are placed in this group. The closest relatives of the Phascolarctidae are the wombats, which comprise the family Vombatidae.
Australidelphia is the superorder that contains roughly three-quarters of all marsupials, including all those native to Australasia and a single species — the monito del monte — from South America. All other American marsupials are members of the Ameridelphia. Analysis of retrotransposon insertion sites in the nuclear DNA of a variety of marsupials has shown that the South American monito del monte's lineage is the most basal of the superorder.
Phascolarctos is a genus of marsupials with one extant species, the koala Phascolarctos cinereus, an iconic animal of Australia. Several extinct species of the genus are known from fossil material, these were also large tree dwellers that browsed on Eucalyptus leaves.
Thylacoleo is an extinct genus of carnivorous marsupials that lived in Australia from the late Pliocene to the late Pleistocene. Some of these marsupial lions were the largest mammalian predators in Australia of their time, with Thylacoleo carnifex approaching the weight of a lioness. The estimated average weight for the species ranges from 101 to 130 kg.
Marada arcanum is a species of Vombatiformes discovered in 2001 at the Oligocene Hiatus Site at Riversleigh. It is the only member of the genus Marada. It exhibits plesiomorphic and apomorphic features making the determination of its taxonomic placement difficult. It has been placed within its own family, Maradidae. The specimen consists of the right dentary, with the first incisor but missing the crown, the whole of the horizontal ramus with intact premolar three and molars one to four. The posterior is missing the coronoid process, the articular condyle and the angular process.
Thylacoleonidae is a family of extinct carnivorous marsupials from Australia, referred to as marsupial lions. The best known is Thylacoleo carnifex, also called the marsupial lion. The clade ranged from the Late Oligocene to the Pleistocene, with some species the size of a possum and others as large as that of a leopard. As a whole, they were largely arboreal, in contrast to the mostly terrestrial dasyuromorphs, monitor lizards and mekosuchines.
Palorchestes is an extinct genus of terrestrial, herbivorous marsupials of the family Palorchestidae. The genus was endemic to Australia, living from the Miocene through to the Pleistocene epochs.
Nimbadon is an extinct genus of marsupial, that lived from the Late Oligocene to the Miocene epoches. Many fossils have been found in the Riversleigh World Heritage property in north-western Queensland. Unlike most members of the family, it is thought to have an arboreal, rather than terrestrial lifestyle.
Phascolonus is an extinct genus of giant wombat known from the Pliocene and Pleistocene of Australia. There is only a single species, Phascolonus gigas, the largest wombat ever known to have existed, estimated to weigh as much as 200 kg or 360 kg (790 lb). P. gigas was described by Richard Owen in 1859. Phascolomys magnus is a probable junior synonym. P. gigas is distinguished from other wombats by its strap-shaped upper incisors. The cranial roof is noticeably inwardly depressed. The species was abundant across Australia, with remains having been found in all states except Western Australia. It is suggested to have had a preference for arid and semi-arid inland habitats, with a diet consisting of a high amount of low quality vegetation. Though it likely had wide home-ranges, it probably did not stray far from fresh water sources. Abundant remains of the taxon are known from Pleistocene of Lake Callabonna in South Australia. Unlike its living relatives, it is has been argued that it is unlikely that Phascolonus was a burrower. Phascolonus disappeared during the Late Pleistocene Quaternary extinction event together with many other large Australian animals, following the arrival of humans to the Australian continent. Phylogenetic analysis suggests that is closely related to the other giant wombat genera Ramsayia and Sedophascolomys.
Silvabestius is an extinct genus of marsupial dating to the Early Miocene. They were grazing animals about the size of a modern sheep.
Nototherium is an extinct genus of diprotodontid marsupial from Australia and New Guinea. This mammal had hypsodont molars and weighed around 500kg. It was a relative of the larger Diprotodon and a distant kin to modern wombats.
Warendja is an extinct genus of wombat. It is known from two species, W. encorensis from the Late Miocene Riversleigh site in Queensland, and W. wakefieldi known from the Pleistocene of South Australia, New South Wales, and Victoria. The two species are primarily distinguished by features of their enamel. It became extinct as part of the Quaternary extinction event. Warendja wakefieldi is estimated to have weighed about 10 kg. Warendja thought to be relatively basal amongst wombats, being the most primitive member to possess hypselodont cheek teeth. The morphology of the humerus of W. wakefieldi suggests that it engaged in scratch-digging.
Ramsayia is an extinct genus of giant wombat, weighing around 100 kg. Ramsayia is known from two species, Ramsayia lemleyi from the Pliocene of Queensland, and Ramsayia magna from the Pliocene to Late Pleistocene of Queensland and New South Wales. The skull superficially resembles that of the giant beavers Castoroides and Trogontherium. The large premaxillary spine suggests it possessed a large fleshy nose. The shape of the skull of R. magna suggests that it did not engage in burrowing. Cladistic analysis suggests that it is closely related to the other giant wombat genera Phascolonus and Sedophascolomys. Like other giant wombats, its size is thought to have been adaption to feeding on large amounts of low quality vegetation.
Ngapakaldia is an extinct genus of diprotodontid marsupials, related to the modern koala and wombat. Around the size of a sheep, it was a ground-dwelling herbivore that lived around the vegetated shores of lakes in Central Australia during the Late Oligocene.
Riversleigh fauna is the collective term for any species of animal identified in fossil sites located in the Riversleigh World Heritage Area.
Propalorchestes is a fossil genus of Diprotodontidae, mammals that existed in Australia.
Karen H. Black, born about 1970, is a palaeontologist at the University of New South Wales. Black is the leading author on research describing new families, genera and species of fossil mammals. She is interested in understanding faunal change and community structure in order to gain new understandings of past, current and future changes in biodiversity which are driven by climate.
Sedophascolomys is an extinct genus of wombat known from the Pliocene and Pleistocene of Australia. There is a single recognised species, S. medius, which was formerly placed in the invalid genus Phascolomys. It was found in the northeastern and eastern regions of the continent. It is estimated to be somewhat larger than extant wombats, with a body mass of 70-75 kilograms. The youngest remains of the genus date to the Late Pleistocene, within the last 50,000 years. It is thought to be closely related to the giant wombat genera Phascolonus and Ramsayia.