Nimbadon Temporal range: | |
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Composite N. lavarackorum skeleton from the Riversleigh site | |
N. lavarackorum mother and juvenile (reconstruction) by Peter Schouten | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Infraclass: | Marsupialia |
Order: | Diprotodontia |
Superfamily: | † Diprotodontoidea |
Genus: | † Nimbadon Hand, Archer, Godthelp, Rich & Pledge, 1993. [1] |
Species | |
†Nimbadon lavarackorum |
Nimbadon is an extinct genus of marsupial, that lived from the Late Oligocene to the Miocene epoches. [1] Many fossils have been found in the Riversleigh World Heritage property in north-western Queensland. It is thought to have an arboreal lifestyle. [2]
In 1990, skulls were unearthed in a previously unknown cave in the region. Researchers estimate that the first species of Nimbadon first appeared about 25 million years ago [1] and died out about 12 million years ago, perhaps from climate change-induced habitat loss.
Nimbadon lavarackorum is described as being koala-like. It is known from as many as 24 well-articulated specimens. The species was a tree-dweller, mainly feeding on stems and leaves. The feet and claws were large, being superficially similar to those of the koala. They retracted their claws when walking. [3]
While originally classified as a member of the family Diprotodontidae, a primarily terrestrial group, [1] [2] some later studies suggested a more basal position within the Diprotodontoidea. [4]
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 remains were first unearthed in 1830 in Wellington Caves, New South Wales, and contemporaneous paleontologists guessed they belonged to rhinos, elephants, hippos or dugongs. Diprotodon was formally described by English naturalist Richard Owen in 1838, and was the first named Australian fossil mammal, and led Owen to become the foremost authority of his time on other marsupials and Australian megafauna, which were 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 order Peramelemorphia includes the bandicoots and bilbies. All members of the order are endemic to Australia-New Guinea and most have the characteristic bandicoot shape: a plump, arch-backed body with a long, delicately tapering snout, very large upright ears, relatively long, thin legs, and a thin tail. Their size varies from about 140 grams up to 4 kilograms, but most species are about one kilogram.
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.
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.
Riversleigh World Heritage Area is Australia's most famous fossil location, recognised for the series of well preserved fossils deposited from the Late Oligocene to more recent geological periods. The fossiliferous limestone system is located near the Gregory River in the north-west of Queensland, an environment that was once a very wet rainforest that became more arid as the Gondwanan land masses separated and the Australian continent moved north. The approximately 100 square kilometres (39 sq mi) area has fossil remains of ancient mammals, birds, and reptiles of the Oligocene and Miocene ages, many of which were discovered and are only known from the Riversleigh area; the species that have occurred there are known as the Riversleigh fauna.
Mystacinidae is a family of unusual bats, the New Zealand short-tailed bats. There is one living genus, Mystacina, with two species, one of which could have possibly become extinct in the 1960s. They are medium-sized bats, about 6 centimetres (2.4 in) in length, with grey, velvety fur.
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.
The Riversleigh rainforest koala is an extinct marsupial, closely related to the extant koala, that inhabited northwestern Queensland in the early-middle Miocene. It is the only species assigned to the genus Nimiokoala. Along with species of sister genus Litokoala, the Riversleigh rainforest koala is the smallest representative of family Phascolarctidae. Based on cladistic analysis, Nimiokoala is one of the more basal genera of Phascolarctide. It died out due to climate change rendering the environment more arid. It probably had a more generalized diet than that of the modern species, but its exact food preferences are unknown.
Diprotodontidae is an extinct family of large herbivorous marsupials, endemic to Australia and New Guinea during the Oligocene through Pleistocene periods from 28.4 million to 40,000 years ago.
Litokoala is an extinct genus of marsupials, and along with Nimiokoala, is closely related to the modern koala. The three genera may have diverged at an earlier date, although the drying of the continent and the expansion of Eucalyptus forests towards the late Miocene may have delayed the evolution of cranial features unique to the modern genera. This indicates that either fossil genus could be an ancestor of the modern genus, or the modern genus has a common ancestor to both. More material needs collection to improve their taxonomical relationships.
Naraboryctes philcreaseri is a fossil species of marsupial found at early Miocene deposits of Boodjamulla National Park of Riversleigh area, northwestern Queensland, Australia.
Malleodectes is a genus of unusual marsupial, first discovered in 2011 at Riversleigh, Queensland, Australia. It could grow as large as a ferret, and lived in the Miocene, 17 million years ago. The reason for its name, which means "Hammer Biter", is because it has blunt, hammer-like teeth, not known from any other mammal extant or extinct. However, Scott Hocknull from the Queensland Museum has noticed similarities to the modern pink-tongued skink, a reptile specialised for eating snails. This suggests that Malleodectes too was a specialised snail hunter.
Priscakoala is an extinct genus of koala from the Early Miocene of Riversleigh, Australia. It has one species: Priscakoala lucyturnbullae.
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.
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.
Madakoala is a genus of extinct phascolarctid marsupials with three known species, Madakoala devisi,Madakoala wellsiandMadakoala robustus. It is allied to extinct genera Invictokoala, Koobor, Litokoala, Nimiokoala, Perikoala, Phascolarctos and Priscakoala, along with Phascolarctos, the genus of the existing koala. Madakoala went extinct around 280,000 years ago in the Pleistocene epoch. They are known to exist by limited cranial material in fossils, so the existence of some of the subspecies is questionable because of missing dental data.