Tarbosaurus
Late Cretaceous
Nemegt Formation
Gobi Desert
Mongolia

Tarbosaurus is a close relative of Tyrannosaurus rex and occupied a similar apex predator role in its environment, preying on large hadrosaurs and other dinosaurs in river floodplain ecosystems.

24mm very worn tooth. From the bottom view it’s clear it is a tyrannosaurid, but the size and preservation leaves open the possibility it might be Alioramus. Either way, it’s ridiculously rare.