The last dicynodont? Re-assessing the taxonomic and temporal relationships of a contentious Australian fossil

Dicynodonts, a lineage of non-mammalian therapsids, who's derived taxa evolved edentulous beaked jaws sporting a pair of caniniform tusks, dominated the herbivorous terrestrial vertebrate fauna for much of the Permian and Triassic periods. Long assumed to have met their demise during the end-Triassic extinction event, the discovery of a fragmentary possible dicynodont in Cretaceous rocks in Queensland Australia, potentially extended the longevity of the lineage by nearly 100 million years. This study reassesses the geological, anatomical and historical aspects of this specimen through museum archival research, detrital zircon geochronology, trace element analysis and x-ray synchrotron microtomography, and present new knowledge regarding its temporal, geographical and biological origins, supporting a late Cenozoic (Pliocene-Pleistocene) mammalian megafaunal affinity for the specimen, resulting in a lack of evidence for post-Triassic survival of dicynodonts.

Gondwana Research

Gondwana Research

77

1342-937X

N/A

N/A

20