By Phil Myers
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
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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.
Contributors
Phil Myers (author), Museum of Zoology, University of Michigan.
