Nanotyrannus Rex Tooth
Age: Cretaceous Age 67.5 - 65 Million years old
From: Hell Creek Formation, Perkins County, South Dakota
Nanotyrannus ("dwarf tyrant") is a potentially dubious genus of tyrannosaurid dinosaur. It is known only from two specimens (possibly three), which are potentially juvenile specimens of the contemporary genus Tyrannosaurus rex.
2.5 x 1 x .65 inches, 23.3 grams