1.33" Tyrannosaur (Nanotyrannus) Premax Tooth - South Dakota

This is a 1.33" long Tyrannosaur premaxillary tooth likely of the species Nanotyrannus lancensis from the Hell Creek Formation of South Dakota. This tooth is in excellent condition with great enamel preservation. There is some feeding wear at the tip.

These oddly shaped teeth with two ridges located on the lingual side where originally described as Aublysodon more than a century ago based off of isolated teeth and jaw fragments. More recent discoveries of more complete Tyrannosaur skeletons from this formation has lead to the discovery that these teeth are actually the premaxillary teeth from juveniles of other Tyrannosaur species.

There is a hot debate among paleontologists about whether Nanotyrannus and Tyrannosaurus rex (T-Rex) are really the same species, with Nanotyrannus representing juveniles. Recent finds that are soon to be published should put this debate to rest, definitively proving that Nanotyrannus is in fact a separate genus and valid genus. Nano teeth tend to be much more finely serrated, and much thinner/blade like t-rex teeth, in addition to being smaller.