Very tiny tyrannosaurid tooth

[Thefossilman92]

I have this very tiny tyrannosaurid tooth from hell creek formation, south dakota.
Im wondering if it's possible to know if the tooth is from a infant nano or t-rex?

Distal serration density: about 6/mm
Can't see any intact serrations on the mesial side.
Crown Height: 4 mm
Crown base-lenght: 2,5 mm
Crown base-width: under 1 millimeter, about 0,8 mm to roughly estimate (very hard to measure this one).

 

Edited July 23, 2022 by Thefossilman92

[Darktooth]

@Troodon

[jikohr]

I could be wrong but the mesial carinae looks like it's intact in a few places (picture 5) and was never serrated. It's really straight too. 

Could it be raptor?

[Troodon]

Hard to ID a tooth this small.  The denticles toward the tip say its a Tyrannosaurid.  Its not robust to say T rex but like I said hard to ID these micro teeth

[Dino Dad 81]

I think the denticle shape is going to get you tyranno'ed, but that chisel look may just be because of your pics. I'm finding that shooting the distal carina diagonally with light coming from above and straight behind the tooth does a good job of picking up the dromie roundness if it's there.

 

Here's a shot I took of a tooth that nudged Troodon to the dromie side of the fence:

 

[Dino Dad 81]

Man, he beat me to it. But it looks like I'm learning! 

[Thefossilman92]

Thank you all for your replies When I looked at the tooth trough the microscope I tried different directions for the light and the serrations are chisel shaped and not rounded like a dromaeosaur. When I'm looking at the tooth myself, the cross-section of the base reminds me of a rex, I don't see any compression there. But since It's so slender it also points at being a nano, although I know that rex teeth look different depending on placement in the jaw. I have very little knowledge about Tyrannosaurid teeth this small and how the morphology differs from adult teeth, I wish there was more to read about this. If anyone has come across any publication about infant tyrannosaur teeth feel free to share it 

[ThePhysicist]

5 hours ago, Thefossilman92 said:

I have very little knowledge about Tyrannosaurid teeth this small and how the morphology differs from adult teeth, I wish there was more to read about this. If anyone has come across any publication about infant tyrannosaur teeth feel free to share it 

 

No one really has good knowledge of Tyrannosaur teeth this small since very few specimens have been found. There has been a remarkable individual of a very young Tarbosaurus (close relative of T. rex) which has a nearly complete dentition. Though Tarbosaurus is a "robust" Tyrannosaurid in that adult teeth are thick like T. rex, it started out with compressed, ziphodont teeth. If this is the case in T. rex, and if Nanotyrannus is a distinct animal, for small teeth like this the two would likely be indistinguishable. 

 

^ Tsuihiji et al. (2011)

 

Most of my Tyrannosaur teeth are juveniles, so I've given some thought to that question, though I am in no way a professional. 

[Thefossilman92]

6 hours ago, ThePhysicist said:

 

No one really has good knowledge of Tyrannosaur teeth this small since very few specimens have been found. There has been a remarkable individual of a very young Tarbosaurus (close relative of T. rex) which has a nearly complete dentition. Though Tarbosaurus is a "robust" Tyrannosaurid in that adult teeth are thick like T. rex, it started out with compressed, ziphodont teeth. If this is the case in T. rex, and if Nanotyrannus is a distinct animal, for small teeth like this the two would likely be indistinguishable. 

 

^ Tsuihiji et al. (2011)

 

Most of my Tyrannosaur teeth are juveniles, so I've given some thought to that question, though I am in no way a professional. 

Thanks!