Order MARSUPIALIA
Marsupials include kangaroos, koalas, wallabies, wombats, bandicoots, and opossums. The red kangaroo (Macropus rufus) is the largest of them that can reach a height of six feet when standing on hind legs and weigh as much as 80 kg. The smallest living marsupials include the pilbara (Ningaui timealeyi) that weighs less than 3.0 grams and Planigale ingrami that measures 4.7 inches in length and weighs 4 grams.
The smallest gliding marsupial is the honey possum (Tarsipes rostratus) which feeds on nectar and pollen from flowers. The earliest known marsupial, Sinodelphys szalayi, lived about 125 million years ago in China. Now there are more than 150 species of extinct marsupials known. Marsupials evolved in North America from where they migrated to South America and then into Australia via Antarctica corridor and then diversified to produce about 300 extant species.
Some were left back in South America which was an island continent till recently. The New WorldMarsupials are grouped into two families that include 15 genera. The Virginia opossum (Didelphis virginiana) is the only marsupial that has spread to North America north of Mexico.
Unlike monotremes, marsupials suckle their young with nippled mammary glands, whose number is variable from two in koalas and wombats to as many as 27 in short-tailed opossum, Monodelphis. Honey Possum (Tarsipes rostratus) has only 22 teeth and numbats have 52 teeth that is the maximum number in marsupials.
In pygmy rock wallaby (Petrogale concinna), molars are continuously replaced.Gestation period varies with 8 days in the marsupial cat (Dasyurus viverrinus) and 40 days in red-necked wallaby (Wallabia rufogrisea). Pygmy possum (Burramys parvus) lives in the mountains, stores food and hibernates for about 6 months. The newborn young of Julia Creek Dunnart (Sminthopsis douglasi) are tiny and are the only mammals that can breathe through their skin.
1. Family DIDELPHIDAE, Opossum and American water opossum
2. DASYURIDAE, Tiger cat
3. THYLACINIDAE, Tasmanian wolf (extinct)
4. MYRMECOBIIDAE, Numbat or Marsupial anteater
5. NOTORYCTIDAE, Marsupial mole
6. PERAMELIDAE, Bandicoots, pouched mouse and hare wallaby
7. COENOLESTIDAE, Coenolestes
8. PHALANGERIDAE (=PETAURIDAE), Bushtail possum; Cuscuses; Flying phalanger (Petaurus)
9. PHASCOLARCTIDAE, Koala (Phascolarctos)
10. PHASCOLOMIDAE (=WOMBATIDAE), Wombats (Phascolomys)
11. MACROPODIDAE, Kangaroos and Wallabies
12. MICROBIOTHERIDAE, Monito del Monte
13. THYLACOMYIDAE, Bilbies
14. BURRAMYIDAE, Pygmy possums
15. TARSIPEDIDAE, Honey possums
16. POTORIDAE, Rat kangaroos; Potoroos
17. AEROBATIDAE, Feather-tailed gliders
18. HYPSIPRYMNODONTIDAE, Musky Rat Kangaroos