Fossil Brontotherium (Titanothere) Molar - South Dakota

This is a molar of Brontotherium, a Titanothere, collected from the Eocene aged Chadron Formation of South Dakota. This specimen was collected, prepared and identified by the Black Hills Institute.

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.