This is a more comprehensive list of animals found in Australia, but definitely is not the definitive list. We have attempted to give you some detail on the better known species, but fall short on being an encyclopaedic resource. So please reference other sites listed under our resources. 
 

Black-footed Rock-Wallaby - Petrogale lateralis
Blainville's Beaked Whale - Mesoplodon densirostris
Bottlenose Dolphin - Tursiops truncatus
Bridled Nailtail Wallaby* - Onychogalea fraenata

Brush-tailed Possum - Trichosurus vulpecula: Brushtail possums are among the most adaptable of the native mammals, living in a variety of habitats including house roofs and chimneys. Click here for more info.

Brush-tailed Rock-Wallaby* - Petrogale penicillata
Burrowing Bettong (Boodie)* - Bettongia lesueur

 

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Common Brushtail Possum - Trichosurus vulpecula
Common Dolphin - Delphinus delphis
Common Ringtail Possum - Pseudocheirus peregrinus
Common Wallaroo or Euro - Macropus robustus
Common Wombat - Vombatus ursinus
Cuvier's Beaked Whale - Ziphius cavirostris

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Dingo - Canis Lupus Dingo: is a primitive dog thought to have evolved from the Pale-footed Wolf (also known as the Indian Wolf) about 6,000-10,000 years ago in Southern Asia. Did you know that dingos have only lived in Australia for between 3,500 and 4,000 years, migrating to Australia most probably with the help of Aborigines? The Dingo is now being protected in many regions, because of their vital role in the ecosystem. It was listed as an indigenous animal under the Threatened Species Conservation Act of 1995 - a far cry from its original status as "pest animal". 

A feature that distinguishes the dingo from the domestic dog is its inability to bark. Instead it howls. It is Australia's largest mammalian carnivore. The arrival of Dingos is thought (not proven) to have contributed to the extinction of Thylacines from mainland Australia.

Great articles can be found here (thanks to Rob):
- http://www.apscience.org.au/projects/APSF_06_2/apsf_06_2.htm 
- http://www.colongwilderness.org.au/Dingo/Dingo_nom_text.pdf 
- http://clix.to/dingodiscoverycentre 

Dugong - Dugong dugon: a large, up to 3m, grey brown bulbous animal with a flattened fluked tail, like that of a whale, no dorsal fin, paddle like flippers and distinctive head shape. The broad flat muzzle and mouth are angled down to enable ease of grazing along the seabed. Eyes and ears are small reflecting the animal's lack of reliance on these senses.

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Eastern Barred Bandicoot* - Parameles gunii
Eastern Grey Kangaroo - Macropus giganteus
Eastern Pygmy-Possum  - Cercartetus nanus 
Eastern Quoll - Dasyurus viverrinus
Echidna - Tachyglossus aculeatus

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False Killer Whale - Pseudorca crassidens: a slender dark dolphin-size whale of 6m with a small, rounded conical head. Characteristic features include a slender sickle shaped dorsal fin and a prominent bump or bulge on the leading edge of each flipper. Its common name is slightly misleading as its main resemblance to the Killer Whale, is its strong set of large conical teeth.

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Ginkgo-toothed Beaked Whale - Mesoplodon ginkgodens

Gliding Possum - marsupials. There are five species in New South Wales: feathertail gliders, sugar gliders, squirrel gliders, yellow-bellied gliders, and greater gliders. Gliders can cover distances of more than 100 m in a single leap, gliding on a thin sheet of skin between their forepaws and ankles.

Gray's Beaked Whale - Mesoplodon grayi 

   

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Hector's Beaked Whale - Mesoplodon hectori

Humpback Whale* - Megaptera novaeangliae: has distinctive knobbly protuberances on the head and long flippers making this one of the most easily recognised of the large baleen whales. Its name is derived from the hump under the dorsal fin, which is particularly noticeable when the whale arches its back to dive. 

It reaches a maximum length of 15 - 18m and weight of 40 tonnes. This is one of the most studied of the great whales as individuals can be recognised by characteristic black and white patterns especially on the underside of the tail.

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Kangaroo - Types of kangaroos include the Eastern Grey Kangaroo, the Lumholtz's Tree Kangaroo, the Matschie's Tree-Kangaroo, the Musky Rat-Kangaroo, the Red Kangaroo, and the Western Grey Kangaroo

Koala* - Phascolarctos cinereus: This small, tree-dwelling, herbivorous marsupial averages about 9kg in weight. It's fur is thick and usually ash grey with a tinge of brown in places. Click here for more info. 

Killer Whale (Orca) - Orcinus orca: At a length of nine metres and weight of over five tonnes, the Killer Whale, Orcinus orca this is the largest member of the dolphin family. A strikingly marked animal characterised by a body pattern of dramatically contrasting areas of intense black and white. The rounded head, indistinct beak, large pointed teeth and prominent upright dorsal fin complete what is considered one of the oceans most impressive mammals. There is probably no other cetacean so appropriately named.

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Leopard Seal - Hydrurga leptonyx: a member of the 'true seal' group, whose locomotion on land is best described as wriggling - a series of muscular body ripples with some assistance from the front flippers. The long body is dark grey to silver with darker grey flippers and spotting on the shoulders, throat and sides. The most imposing feature is its massive head, long snout and gaping jaws, giving the animal an overall reptilian appearance. The common name refers to the body markings but could equally describe its behaviour.

Leadbeater's Possum* - Gymnobelideus leadbeateri: Leadbeater's Possum are 40cm from nose to tail. They are nocturnal, tree-dwelling marsupials covered in soft brown-grey fur with white underparts and beautifully marked facial features. They appear similar to Sugar Gliders except that they lack a gliding membrane and have a club-shaped tail, broader near the tip than at the base. Leadbeater's Possums are largely confined to the forests of the Central Highlands of Victoria. The most important features of their habitat are tree hollows and an understories of wattle. Leadbeater's Possum nest and shelter in the tree hollows of decaying 400 year old trees specifically, Mountain Ash .

Little Pygmy-Possum - Cercartetus lepidus 
Long-footed Potoroo* - Potorous longipes
Longfin Pilot Whale - Globicephala melaena
Longman's Beaked Whale - Indopacetus pacificus
Lumholtz's Tree Kangaroo - Dendrolagus lumholtzi

 

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Mareeba Rock-Wallaby - Petrogale mareeba 
Matschie's Tree-Kangaroo - Dendrolagus matschiei

Minke Whale - Balaenoptera acutorostrata: a small streamlined baleen whale with a maximum length 10m. It has a sleek pointed head with a diagnostic single longitudinal ridge, narrow pointed flippers each with a white stripe and a curved dorsal fin set well back on the body. This whale has an inquisitive nature, and often approaches boats and people in the water.

Musky Rat-Kangaroo - Hypsiprymnodon moschatus

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Northern Hairy-nosed Wombat* - Lasiorhinus krefftii

Numbat - Myrmecobius fasciatus: These termite eaters (consuming up to 20,000 per day, the equivalent of ten per cent of their body weight) can be recognised by their slender graceful bodies, which are banded and usually reddish-brown. Click here for more info.

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Parma Wallaby* - Macropus parma

Platypus - Ornithorhynchus anatinus: The platypus, with its duck bill and webbed feet, is a unique Australian animal. Click here for more info. 

Possum (see Brushtail, Gliding, Leadbeater, and Little Pygmy Possums)
Pygmy Sperm Whale - Kogia breviceps 

 

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Quokka - Setonix brachyurus: Quokkas have rounded bodies with a short tail and a hunched posture. They have small rounded ears and a wide face that is much more flattened than that of other wallabies. Click here for more info. 

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Red Kangaroo - Macropus rufus

Red-legged Pademelon - Thylogale stigmatica
Red-necked Pademelon - Thylogale thetis
Red-necked Wallaby - Macropus rufogriseus

Rock Wallaby - Petrogale brachyotis: These small marsupials are extremely attractive and often have interesting markings. Their hind feet are thick and padded and resemble the radial tyres of cars - this is good for moving around their rocky habitat. Click here for more info.

Rufous Bettong - Aepyprymnus rufescens

 

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Shepherd's Beaked Whale - Tasmacetus shepherdi
Short-finned Pilot Whale - Globicephala macrorhynchus

Southern Hairy-nosed Wombat - Lasiorhinus latifrons: Their hairy muzzles, silky grey fur and erect pointy ears easily identify the two Hairy-nosed species. Slightly smaller than the Common Wombat, the Southern Hairy-nosed Wombat ranges in weight from 19-32kg, and grows to almost a metre in length. As with all wombats, the Southern Hairy-nosed Wombat is a marsupial. Females have pouches that face backwards, opening toward the rear limbs. Wombat do have tails, though they are difficult to see as they are very short. Southern Hairy-nosed Wombats are found in southern South Australia from the western side of the Murray River from Swanreach to Morgan, the southern border of the Nullarbor Plain to the east of Eucla and some small colonies in the Gawler Ranges, on the Eyre and York Peninsulas. These regions are generally arid or semi arid deserts with daily temperatures in excess of 40°c that fall below zero over night. Southern Hairy-nosed Wombats eat the fresh shoots of spear grasses and wallaby grass. During times of drought, they will eat blue bush and bindi. Southern Hairy-nosed Wombats have a cleft upper lip that allows them to eat shoots close to the ground.

Southern Bottlenose Whale - Hyperoodon planifrons
Southern Right Whale* - Baleana glacialis australis 
Spectacled Hare-Wallaby* - Lagorchestes conspicillatus
Sperm Whale - Physeter macrocephalus
Spotted-tailed Quoll* - Dasyurus maculatus
Strap-toothed Whale - Mesoplodon layardii

Striped Dolphin - Stenella coeruleoalba: a small sleek compact dolphin with a long well defined beak, prominent dorsal fin and short tapering flippers. It is the striking body pattern that gives it its name. A bold black stripe runs the full length of the body from behind the eye to the anus. This separates the bluish grey flank from the white ventral surface. A second smaller stripe runs from the front of the eye to the behind the flipper. A third section of dark grey covers the top of the head, the dorsal fin and on towards the back of the body.

Sugar Glider - Petaurus breviceps
Swamp Wallaby - Wallabia bicolor

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Tammar Wallaby - Macropus eugenii
Tasmanian Bettong* - Bettongia gaimardi

Tasmanian Devil - Sarcophilus harrisii: Its spine chilling screeches, black colour, and reputed bad-temper, led the early European settlers to call it "The Devil". Click here for more detail. 

Tasmanian Pademelon - Thylogale billardieri

Thylacine (Historical: Extinct) - Thylacinus cynocephalus: - a species of carnivorous marsupial related to the Tasmania Devil and the Eastern Quoll; Thylacines are also known as Tasmanian Tigers. Several kinds of thylacine have lived in Australia during the past 25 million years, the Powerful Thylacine was the largest of them all. It was also the largest meat-eating marsupial of its time. 

The death of the last known Thylacine in Hobart Zoo, in 1936, marked the end of thylacines for all time. Today, the closest living relatives of the Powerful Thylacine are the dasyurid marsupials, including quolls and the Tasmanian Devil.

True's Beaked Whale - Mesoplodon mirus 

 

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Wallaby - Types of wallabies include the Rock Wallaby, the Agile Wallaby, the Allied Rock-Wallaby, the Black-footed Rock-Wallaby, the Brush-tailed Rock-Wallaby, the Mareeba Rock-Wallaby, the Parma Wallaby, the Swamp Wallaby, the Tammar Wallaby, the Whiptail Wallaby, and the Yellow-footed Rock Wallaby.

Water Buffalo - Bubalus bubalis
Western Grey Kangaroo - Macropus fuliginosus

Whiptail Wallaby - Macropus parryi
Wombat (see Common Wombat or Northern Hairy-nosed Wombat or Southern Hairy-nosed Wombat)

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Yellow-footed Rock Wallaby* - Petrogale xanthopus