Wynyardiidae

Wynyardiidae, an extinct family of possum-like marsupials from the early Miocene of Wynyard in Tasmania, has long been considered to display skeletal features that are intermediate between the primitive polyprotodont and the advanced diprotodont marsupials. The skull examined is missing the right eye socket and opening for the temporal muscles, but the condition of the skull is relatively unfractured. An examination of the latex endocast of the nearly intact neurocranium or the brain case inside the skull, has revealed that Wynyardia's brain is clearly phalangeroid in external morphology, resembling closely that of the extant phalangerid, Trichosurus vulpecula or Common Brushtail Possum.These research findings indicate that by 21 million years ago, an unambiguously phalangerid brain had evolved within the Diprotodonta family, indicating that both species had a common ancestor prior to this date. Research on Wynyardia bassiana 's relationship with fossil phalangerid species of the Miocene is an ongoing process.