Reassessment of the latest Oligocene ruminant from Sardara, the last non-insular mammal from Sardinia (Italy)

The Neogene fauna from Oschiri and Laerru (Sardinia, Italy) are famous for being the oldest known insular community from the Mediterranean Sea (Burdigalian). The only known ruminant specimen from Sardara is often associated to these faunas. Nevertheless, some doubts persist on its specific attribution and age. Here we re-describe the specimen and attribute it to “Amphitragulus” quercyi. This species is only known during the latest Oligocene, between 24.5 and 23 Ma. This chronological range is in agreement with the age attributed to the upper part of the Ussana Formation and the base of the transgressive marine formations of the first sedimentary cycle (Oligo-Aquitanian) of Central Sardinia where the fossil has been found. Instead of being the oldest insular mammal from Sardinia, the Sardara ruminant is the most recent fully continental mammal known in Sardinia and the first one dating from the Oligocene.