Wynyardiidae
Encyclopedia
Wynyardia bassiana, an extinct possum-like marsupial from the early Miocene of Wynyard
in Tasmania
has long been considered to display skeletal features 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. Wynyardia bassiana relationship with fossil phalangerid species of the Miocene is an ongoing process.
Wynyard, Tasmania
Wynyard is a rural town on the north-west coast of Tasmania, Australia. It lies west of Burnie on the Bass Highway at the mouth of the Inglis River....
in Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
has long been considered to display skeletal features 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
Resin casting
Resin casting is a method of plastic casting where a mold is filled with a liquid synthetic resin, which then hardens. It is primarily used for small scale production like industrial prototypes and dentistry...
of the nearly intact neurocranium or the brain case inside the skull, has revealed that Wynyardia's brain is clearly phalangeroid in external morphology
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
, 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. Wynyardia bassiana relationship with fossil phalangerid species of the Miocene is an ongoing process.
Species
- †Wynyardiidae (Osgood 1921)
- †Wynyardia bassiana (Spencer 1901) [†Wynyardia basiana]
- †Muramura williamsi (Pledge in Archer 1987)
- †Muramura pinpensis (Pledge N S 2003)
- †Namilamadeta snideri (Rich & Archer 1979) [Common name †Wombaroo]