Australia: The Land Where Time Began

A biography of the Australian continent 

Riversleigh Petaurids

The living petaurids, comprised of  5 species of gliding possum, all species of Petaurus, and Leadbeater's Possum, (Gymnobelideus leadbeateri) and the striped possums, species of Dactylopsila.

A characteristic of living striped possums is they have a strong smell. They are unknown in the Riversleigh deposits. As there are no known striped possums so far in the Riversleigh deposits it has been suggested that they evolved after the Oligocene-Miocene.

2 petaurines have been found in the Pliocene Hamilton Local Fauna, in Victoria. They showed some similarity to living species, the Squirrel Glider (P. norfolcensis) and the Sugar Glider (P. breviceps). It is not known if they were gliders, but it has been thought unlikely because the Riversleigh rainforests of the time were of the closed canopy type. A pre-Greater Glider has been found in the Hamilton Local Fauna. One suggested alternative to the possible gliders having lived in the rainforests is that owls roosting in the rainforest might have caught the possums outside the rainforest, bringing them back to their roosts and regurgitating the bones under their roosts.

There are many petaurid-like remains in the various Riversleigh deposits that have not yet been studied. The only thing that can be said about these fossils is that at first glance none seem to be closely related to extant petaurid genera. Among them there are many with molars similar to those found in living species, but they often also have a very large posterior premolar. One taxon has been found that appears to have been evolving towards Petaurus/Gymnobelideus type of morphology. Some isolated teeth look very similar to the teeth of extant species. These are not known well enough to assign them to a particular group with any confidence.

They appear to have been abundant in the Riversleigh rainforest of the Oligocene-Miocene.

Sources & Further reading

Michael Archer, Suzanne J. Hand & Henk Godthelp, Australia's Lost World: Riversleigh, world heritage Site, Reed New Holland