7.6" Titanothere (Brontops) Jaw Section - South Dakota

This is a 7.6" long jaw section of the Brontops robustus, a Titanothere. This jaw section contains a pair of molars still in their original position. It was collected from the White River Formation in Pennington County, South Dakota.

Titanothere's are an extinct, massive, mammal that lived during the Eocene. While the very closely resembled a Rhinocerose, they were more closely related to todays horses. They first appeared 54 million years ago and when extinct at the end of the Eocene, 34 million years ago.