A new macropodine genus and species (Marsupialia: Macropodidae) from the early Pleistocene of southwestern Victoria.

Abstract

Baringa nelsonensis n. gen. and sp. is the most abundant marsupial of the early Pleistocene Nelson Bay local fauna, of the Lower Nelson Bay Formation at Nelson Bay, southwestern Victoria. It is unknown elsewhere. Baringa nelsonensis shares similarities in molar and premolar morphology with some species of Thylogale but its I3 and dentary are most similar to those of species of Onychogalea. The presence of a distinct ridge along the ventral margin of the masseteric foramen and the excavation of the jugal below the orbit indicate that the external and second layers of the masseteric musculature were enlarged and powerful. This musculature facilitates forward movement of the dentary. These features along with the peculiar morphology and wear pattern of I1 indicate an unusual masticatory and thus probable dietary adaptation for Baringa nelsonensis.