This large teeth belonged to a Brontotherium, a large hoofed mammal related to horses and rhinos. Brontotherium roamed that scrubby woodlands of South Dakota and Nebraska in large herds during the Oligocene. They were huge mammals standing over 8 feet tall at the shoulders, larger than any present day rhino.

Species: _Titanotherium ingen_

Age: 30 - 35 Million Years Old

Location: Chadron Formation, Pennington County, South Dakota.

Size: Length 9.25 inches or 23 cm width 6.75 inches or 17.2 cm, height 4.5 inches or 12 cm.

Weight: 3176 g / 7 lb.