Australidelphia is the

superorder Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...

that contains roughly three-quarters of all

marsupial Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsupials are endemic to Australasia, Wallacea and the Americas. A distinctive characteristic common to most of these species is that the young are carried in a po ...

s, including all those native to

Australasia Australasia is a region that comprises Australia, New Zealand and some neighbouring islands in the Pacific Ocean. The term is used in a number of different contexts, including geopolitically, physiogeographically, philologically, and ecologica ...

and a single species — the

monito del monte The monito del monte or colocolo opossum, ''Dromiciops gliroides'', also called ''chumaihuén'' in Mapudungun, is a diminutive marsupial native only to southwestern South America (Argentina and Chile). It is the only extant species in the ancient ...

— from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

. All other American marsupials are members of the

Ameridelphia Ameridelphia is traditionally a superorder that includes all marsupials living in the Americas except for the Monito del monte (''Dromiciops''). It is now regarded as a paraphyletic group. Orders The orders within this group are listed below: * ...

. Analysis of

retrotransposon Retrotransposons (also called Class I transposable elements or transposons via RNA intermediates) are a type of genetic component that copy and paste themselves into different genomic locations (transposon) by converting RNA back into DNA through ...

insertion sites in the

nuclear DNA Nuclear DNA (nDNA), or nuclear deoxyribonucleic acid, is the DNA contained within each cell nucleus of a eukaryotic organism. It encodes for the majority of the genome in eukaryotes, with mitochondrial DNA and plastid DNA coding for the rest. It ...

of a variety of marsupials has shown that the South American

lineage Lineage may refer to: Science * Lineage (anthropology), a group that can demonstrate its common descent from an apical ancestor or a direct line of descent from an ancestor * Lineage (evolution), a temporal sequence of individuals, populati ...

is the most basal of the superorder. The Australian australidelphians form a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

, for which the name Euaustralidelphia ("true Australidelphia") has been proposed (the branching order within this group is yet to be determined). The study also showed that the most basal of all marsupial orders are the other two South American groups ( Didelphimorphia and

Paucituberculata Paucituberculata is an order of South American marsupials. Although currently represented only by the seven living species of shrew opossums, this order was formerly much more diverse, with more than 60 extinct species named from the fossil rec ...

, with the former probably branching first). This indicates that Australidelphia arose in South America along with the other major divisions of extant marsupials, and likely reached Australia via Antarctica in a single dispersal event after

Microbiotheria Microbiotheria is an australidelphian marsupial order that encompasses two families, Microbiotheriidae and Woodburnodontidae, and is represented by only one extant species, the monito del monte, and a number of extinct species known from fossi ...

split off.

Phylogeny

Phylogeny of living Australidelphia based on the work of May-Collado, Kilpatrick & Agnarsson 2015 with extinct clades from Black et al. 2012

Taxonomy

The orders within this group are listed below: * Genera †''

Djarthia ''Djarthia'' is an extinct monotypic genus of marsupial. It is the oldest marsupial found in Australia, discovered at the Murgon fossil site in south-eastern Queensland. ''D.'' ''murgonensis'' was described from material identified as Early ...

'' Godthelp, Wroe & Archer 1999 * Order †

Yalkaparidontia ''Yalkaparidon'' is an extinct genus of Australian marsupials, first described in 1988 and known only from the Oligo-Miocene deposits of Riversleigh, northwestern Queensland, Australia. Species Two species, ''Y. coheni'' and ''Y. jonesi'', h ...

Archer, Hand & Godthelp 1988 ** Family †

Yalkaparidontidae ''Yalkaparidon'' is an extinct genus of Australian marsupials, first described in 1988 and known only from the Oligocene, Oligo-Miocene deposits of Australian Fossil Mammal Sites (Riversleigh), Riversleigh, northwestern Queensland, Australia. Sp ...

Archer, Hand & Godthelp 1988 * ?Order

(1 species) ** ?Family

Microbiotheriidae Microbiotheriidae is a family of australidelphian marsupials represented by only one extant species, the monito del monte, and a number of extinct species known from fossils in South America, Western Antarctica, and northeastern Australia. Micr ...

* Order

Dasyuromorphia Dasyuromorphia (, meaning "hairy tail" in Greek) is an order comprising most of the Australian carnivorous marsupials, including quolls, dunnarts, the numbat, the Tasmanian devil, and the thylacine. In Australia, the exceptions include the omn ...

(71 species) ** Family †

Thylacinidae Thylacinidae is an extinct family of carnivorous, superficially dog-like marsupials from the order Dasyuromorphia. The only species to survive into modern times was the thylacine (''Thylacinus cynocephalus''), which became extinct in 1936. The ...

thylacine The thylacine ( , or , also ) (''Thylacinus cynocephalus'') is an extinct carnivorous marsupial that was native to the Australian mainland and the islands of Tasmania and New Guinea. The last known live animal was captured in 1930 in Tasman ...

** Family

Dasyuridae The Dasyuridae are a family of marsupials native to Australia and New Guinea, including 71 extant species divided into 17 genera. Many are small and mouse-like or shrew-like, giving some of them the name marsupial mice or marsupial shrews, but th ...

: antechinuses,

quoll Quolls (; genus ''Dasyurus'') are carnivorous marsupials native to Australia and New Guinea. They are primarily nocturnal and spend most of the day in a den. Of the six species of quoll, four are found in Australia and two in New Guinea. Anoth ...

dunnart Dunnart is a common name for species of the genus ''Sminthopsis'', narrow-footed marsupials the size of a European mouse. They have a largely insectivorous diet. Taxonomy The genus name ''Sminthopsis'' was published by Oldfield Thomas in 18 ...

Tasmanian devil The Tasmanian devil (''Sarcophilus harrisii'') (palawa kani: purinina) is a carnivorous marsupial of the family Dasyuridae. Until recently, it was only found on the island state of Tasmania, but it has been reintroduced to New South Wales in ...

, and allies ** Family

Myrmecobiidae The numbat (''Myrmecobius fasciatus''), also known as the noombat or walpurti, is an insectivorous marsupial. It is diurnal and its diet consists almost exclusively of termites. The species was once widespread across southern Australia, but ...

numbat The numbat (''Myrmecobius fasciatus''), also known as the noombat or walpurti, is an insectivorous marsupial. It is diurnal and its diet consists almost exclusively of termites. The species was once widespread across southern Australia, but ...

* Order

Peramelemorphia The order Peramelemorphia includes the bandicoots and bilbies; it equates approximately to the mainstream of marsupial omnivores. All members of the order are endemic to the twin land masses of Australia-New Guinea and most have the character ...

(21 species) ** Family

Thylacomyidae ''Macrotis'' is a genus of desert-dwelling marsupial omnivores known as bilbies or rabbit-bandicoots; Unabridged they are members of the order Peramelemorphia. At the time of European colonisation of Australia, there were two species. The ...

: bilbies ** Family †Chaeropodidae: pig-footed bandicoots ** Family

Peramelidae The marsupial family Peramelidae contains all of the extant bandicoots. They are found throughout Australia and New Guinea, with at least some species living in every available habitat, from rainforest to desert. Four fossil peramelids are descri ...

bandicoot Bandicoots are a group of more than 20 species of small to medium-sized, terrestrial, largely nocturnal marsupial omnivores in the order Peramelemorphia. They are endemic to the Australia–New Guinea region, including the Bismarck Archipelago t ...

s and allies * Order

Notoryctemorphia Notoryctidae is a family of mammals, allying several extant and fossil species of Australia. The group appear to have diverged from other marsupials at an early stage and are highly specialised to foraging through loose sand; the unusual feature ...

(2 species) ** Family

Notoryctidae Notoryctidae is a family of mammals, allying several extant and fossil species of Australia. The group appear to have diverged from other marsupials at an early stage and are highly specialised to foraging through loose sand; the unusual feature ...

: marsupial moles * Order

Diprotodontia Diprotodontia (, from Greek language, Greek "two forward teeth") is the largest extant order (biology), order of marsupials, with about 155 species, including the kangaroos, Wallaby, wallabies, Phalangeriformes, possums, koala, wombats, and many ...

(117 species) ** Family

Phascolarctidae The Phascolarctidae (''φάσκωλος (phaskolos)'' - pouch or bag, ''ἄρκτος (arktos)'' - bear, from the Greek ''phascolos'' + ''arctos'' meaning pouched bear) is a family of marsupials of the order Diprotodontia, consisting of only one ...

koala The koala or, inaccurately, koala bear (''Phascolarctos cinereus''), is an arboreal herbivorous marsupial native to Australia. It is the only extant representative of the family Phascolarctidae and its closest living relatives are the womb ...

** Family Vombatidae:

wombat Wombats are short-legged, muscular quadrupedal marsupials that are native to Australia. They are about in length with small, stubby tails and weigh between . All three of the extant species are members of the family Vombatidae. They are adap ...

s ** Family

Phalangeridae The Phalangeridae are a family of mostly nocturnal marsupials native to Australia, New Guinea, and Eastern Indonesia, including the cuscuses, brushtail possums, and their close relatives. Considered a type of possum, most species are arboreal, ...

: brushtail possums and cuscuses ** Family

Burramyidae The pygmy possums are a family of small possums that together form the marsupial family Burramyidae. The five extant species of pygmy possum are grouped into two genera. Four of the species are endemic to Australia, with one species also co-occu ...

: pygmy possums ** Family

Tarsipedidae The honey possum or noolbenger (''Tarsipes rostratus''), is a tiny species of marsupial that feeds on the nectar and pollen of a diverse range of flowering plants. Found in southwest Australia, it is an important pollinator for such plants as '' ...

honey possum The honey possum or noolbenger (''Tarsipes rostratus''), is a tiny species of marsupial that feeds on the nectar and pollen of a diverse range of flowering plants. Found in southwest Australia, it is an important pollinator for such plants as '' ...

** Family

Petauridae Petauridae is a family of possums containing 13 species: four species of trioks and striped possum (genus ''Dactylopsila''), eight species of wrist-winged glider (genus ''Petaurus''), and Leadbeater's possum (''Gymnobelideus leadbeateri''), whic ...

striped possum The striped possum or common striped possum (''Dactylopsila trivirgata'') is a member of the marsupial family Petauridae. it is found mainly in New Guinea. The species is black with three white stripes running head to tail, and its head has whi ...

Leadbeater's possum Leadbeater's possum (''Gymnobelideus leadbeateri'') is a critically endangered possum largely restricted to small pockets of alpine ash, mountain ash, and snow gum forests in the Central Highlands of Victoria, Australia, north-east of Melbour ...

yellow-bellied glider The yellow-bellied glider (''Petaurus australis''), also known as the fluffy glider, is an arboreal and nocturnal gliding possum that lives in native eucalypt forests in eastern Australia, from northern Queensland south to Victoria. Habitat ...

sugar glider The sugar glider (''Petaurus breviceps'') is a small, omnivorous, arboreal, and nocturnal gliding possum belonging to the marsupial infraclass. The common name refers to its predilection for sugary foods such as sap and nectar and its ability ...

, mahogany glider,

squirrel glider The squirrel glider (''Petaurus norfolcensis'') is a nocturnal gliding possum. The squirrel glider is one of the wrist-winged gliders of the genus ''Petaurus''. Habitat This species' home range extends from Bordertown near the South Australia ...

** Family

Pseudocheiridae Pseudocheiridae is a family of arboreal marsupials containing 17 extant species of ringtailed possums and close relatives. They are found in forested areas and shrublands throughout Australia and New Guinea. Characteristics Physically, they app ...

: ringtailed possums and allies ** Family

Potoridae Potoroidae is a family of marsupials, small Australian animals known as Bettong, bettongs, Potoroo, potoroos, and rat-kangaroos. All are rabbit-sized, brown, jumping marsupials and resemble a large rodent or a very small wallaby. Taxonomy The ...

: potoroos, rat kangaroos, bettongs ** Family

Acrobatidae The Acrobatidae are a small family of flying and gliding animals, gliding marsupials containing two genera, each with a single species, the feathertail glider (''Acrobates pygmaeus'') from Australia and feather-tailed possum (''Distoechurus penn ...

feathertail glider The feathertail glider (''Acrobates pygmaeus''), also known as the pygmy gliding possum, pygmy glider, pygmy phalanger, flying phalanger and flying mouse, is a species of marsupial native to eastern Australia. It is the world's smallest gliding ...

and

feather-tailed possum The feather-tailed possum (''Distoechurus pennatus'') is a species of marsupial in the family Acrobatidae. It is found in West Papua and Papua New Guinea. It is not to be confused with the feathertail glider, the only other species in the famil ...

** Family

Hypsiprymnodontidae The Hypsiprymnodontidae are a family of macropods, one of two families containing animals commonly referred to as rat-kangaroos. The single known extant genus and species in this family, the musky rat-kangaroo, ''Hypsiprymnodon moschatus'', oc ...

musky rat-kangaroo The musky rat-kangaroo (''Hypsiprymnodon moschatus'') is a small marsupial found only in the rainforests of northeastern Australia. First described in the later 19th century, the only other species are known from fossil specimens. They are simil ...

** Family

Macropodidae Macropodidae is a family of marsupials that includes kangaroos, wallabies, tree-kangaroos, wallaroos, pademelons, quokkas, and several other groups. These genera are allied to the suborder Macropodiformes, containing other macropods, and ar ...

: kangaroos, wallabies, and allies ** Family †

Thylacoleonidae Thylacoleonidae is a family of extinct meat-eating 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 Pleistoc ...

: marsupial lions ** Family †

Palorchestidae Palorchestidae is an extinct family of diprotodont marsupials whose members are sometimes referred to as marsupial tapirs due to their superficial similarity to true tapirs. Genera The family consists of the following four genera: * ''Propalor ...

: marsupial tapirs ** ** ** ** ** Family †

Diprotodontidae The Diprotodontidae are 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. The family consisted of large quadrupedal te ...

: giant wombats ** ** **

Footnotes

References

Australasian realm fauna Mammal superorders Extant Paleocene first appearances Marsupials of Australia Marsupials Metatheria Paleocene mammals of Australia Paleocene mammals of Oceania {{Marsupial-stub