Pseudocheiridaeringtail possums

The Pseudocheiridae, a family of the marsupial order Diprotodontia, contains 5 or 6 genera and 14 species. They are found in Australia and New Guinea. Until recently, members of this family were classified with the petaurids. While there is probably a close phylogenetic relationship between the two groups, pseudocheirids can be distinguished by their sharply crested, selenodont teeth, which contrast with the more rounded, bunodont teeth of petaurids.

Most pseudocheirids have a strongly prehensile tail (weakly so in the great glider and rock ringtail). They are medium sized animals, with most weighing between 0.5 and 2 kg. Like other members of the Diprotodontia, they are syndactylous and diprotodont. Their dental formula is 3/2, 1/0, 3/3, 4/4 = 40 . On the forefeet, digits 1 and 2 are opposable to 3-5. There is a well developed hallux on each hindfoot. The pouch is large and opens anteriorly.

One member of the family, Petauroides, has a gliding membrane much like that of petaurids. It differs, however, in that the membrane extends to the wrist in petaurids but only to the elbow in Petauroides.

Pseudocheirids are generally herbivorous and feed on leaves. Most are arboreal. They have a simple stomach but large cecum, in which bacterial digestion takes place. At least some species are known to be coprophagous, reingesting special feces voided from the cecum

Literature and references cited

Feldhamer, G. A., L. C. Drickamer, S. H. Vessey, and J. F. Merritt. 1999. Mammalogy. Adaptation, Diversity, and Ecology. WCB McGraw-Hill, Boston. xii+563pp.

Marshall, L. G. 1984. Monotremes and marsupials. Pp 59-115 in Anderson, S. and J. Knox Jones, eds, Orders and Families of Recent Mammals of the World. John Wiley and Sons, NY. xii+686 pp.

Strahan, R. (ed.). 1995. Mammals of Australia. Smithsonian Institution Press, Washington, D.C. 756 pp.

Vaughan, T. A. 1986. Mammalogy. Third Edition. Saunders College Publishing, Fort Worth. vi+576 pp.

Vaughan, T. A., J. M. Ryan, N. J. Czaplewski. 2000. Mammalogy. Fourth Edition. Saunders College Publishing, Philadelphia. vii+565pp.

Wilson, D. E., and D. M. Reeder. 1993. Mammal Species of the World, A Taxonomic and Geographic Reference. 2nd edition. Smithsonian Institution Press, Washington. xviii+1206 pp.


Phil Myers (author), Museum of Zoology, University of Michigan-Ann Arbor.


bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


uses smells or other chemicals to communicate


animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.


having the capacity to move from one place to another.


reproduction that includes combining the genetic contribution of two individuals, a male and a female


uses touch to communicate