Hell Creek Dinosaur tooth id help

[jikohr]

Hi everyone!

 

I could really use a second opinion on this one. I'm thinking Dromaeosaur Acheroraptor at first but after looking at more pics I'm not sure if it might be Ricardoestesia or possibly even a juvenile Dakotaraptor. It's Hell Creek, about .35 inches. Serrations don't veer off to one side near the base so I really don't think it's a baby Nano. If pictures from another angle are needed to make an id let me know. Any feedback is greatly appreciated as always!

 

 

[Runner64]

Do you have serration density on both sides /5mm?  That would be most helpful for identifying these small teeth.  Looking at it, it doesn't have typical ridges of acheroraptor and is too robust to be richardoestia.

 

What is location info you were given?

[jikohr]

8 minutes ago, Runner64 said:

Do you have serration density on both sides /5mm?  That would be most helpful for identifying these small teeth.  Looking at it, it doesn't have typical ridges of acheroraptor and is too robust to be richardoestia.

 

What is location info you were given?

 

Powder River County, Montana

 

I don't have the serration count off the top of my head. I'll post when I get back home.

 

[Troodon]

Looks like a lateral  Tyrannosaurid tooth.   Can you take a photo of the base and a complete view of the mesial carina.  Best to use putty to hold the tooth, fingers hide everything including the tooth.

[jikohr]

2 hours ago, Runner64 said:

Do you have serration density on both sides /5mm?  That would be most helpful for identifying these small teeth.  Looking at it, it doesn't have typical ridges of acheroraptor and is too robust to be richardoestia.

 

What is location info you were given?

 

1 hour ago, Troodon said:

Looks like a lateral  Tyrannosaurid tooth.   Can you take a photo of the base and a complete view of the mesial carina.  Best to use putty to hold the tooth, fingers hide everything including the tooth.

posterior serrations are 28 per 5 mm

anterior serrations are 32 per 5mm

[Runner64]

@Troodon density seems a bit high for tyrannosaur, right? Any chance Dakotaraptor?

[jikohr]

2 minutes ago, Runner64 said:

@Troodon density seems a bit high for tyrannosaur, right? Any chance Dakotaraptor?

I honestly didn't consider Tyrannosaur to be a possibility for this because the mesial carina doesn't veer off at the base on the anterior side and I had always learned that that was how to distinguish Tyrannosaur from other carnivorous dinosaurs. is that not correct? If that's a false assumption on my part please let me know because I also have a .75 inch tooth that was labeled as raptor but I identified as Nano but would LOVE to relabel it raptor.

[Troodon]

12 minutes ago, Runner64 said:

@Troodon density seems a bit high for tyrannosaur, right? Any chance Dakotaraptor?

Yes but I would expect it to be high on such a small tooth.   Dakotaraptor ? Need to see the denticles but cross-section of base not ideal.

 

9 minutes ago, jikohr said:

I honestly didn't consider Tyrannosaur to be a possibility for this because the mesial carina doesn't veer off at the base on the anterior side and I had always learned that that was how to distinguish Tyrannosaur from other carnivorous dinosaurs. is that not correct? If that's a false assumption on my part please let me know because I also have a .75 inch tooth that was labeled as raptor but I identified as Nano but would LOVE to relabel it raptor.

 

On the study I with 50 teeth did most had a lingual twist but not all and that included Nano and Trex.

 

Can you take a closup, straight in, of the distal serrations?  Need to see the shape of the denticles

[jikohr]

6 minutes ago, Troodon said:

Yes but I would expect it to be high on such a small tooth.   Dakotaraptor ? Need to see the denticles but cross-section of base not ideal.

 

 

On the study I with 50 teeth did most had a lingual twist but not all and that included Nano and Trex.

 

Can you take a closup, straight in, of the distal serrations?  Need to see the shape of the denticles

So is the twist thing were all teeth with lingual twists are Tyrannosaurs but not all Tyrannosaur teeth have a lingual twist?

[jikohr]

13 minutes ago, Troodon said:

Yes but I would expect it to be high on such a small tooth.   Dakotaraptor ? Need to see the denticles but cross-section of base not ideal.

 

 

On the study I with 50 teeth did most had a lingual twist but not all and that included Nano and Trex.

 

Can you take a closup, straight in, of the distal serrations?  Need to see the shape of the denticles

forgot this one

[Troodon]

Not necessarily there are others with twists like Dromaeosaurus.   Sorry the denticles are not coming in  focus to make any sense of them

[jikohr]

Just now, Troodon said:

Not necessarily there are others with twists like Dromaeosaurus.   Sorry the denticles are not coming in  focus to make any sense of them

What am I looking for in denticle shape? What differentiates small Tyrannosaur from Dromaeosaur?

[jikohr]

17 minutes ago, Troodon said:

Not necessarily there are others with twists like Dromaeosaurus.   Sorry the denticles are not coming in  focus to make any sense of them

are these better?

[jikohr]

50 minutes ago, Troodon said:

Not necessarily there are others with twists like Dromaeosaurus.   Sorry the denticles are not coming in  focus to make any sense of them

the best shot I could get.

I really need to get some putty.

[Troodon]

The shape is what we are looking for.  Dakotaraptor denticles are very different than tyrannosaurids but other Dromaeosaurids species can have different denticles both in shape and density.   For example, Dromaeosaurus found in Campanian deposits is similar to those of tyrannosaurids, chisel shape. Dakotaraptor is narrow with a rounded end.    The last group of photos works for me, thanks, they are chisel shaped which is tyrannosaurid.     So the tooth is a tyrannosaurid and would lean toward a Nanotyrannus but cannot rule out T rex given the size.  

[jikohr]

10 hours ago, Troodon said:

The shape is what we are looking for.  Dakotaraptor denticles are very different than tyrannosaurids but other Dromaeosaurids species can have different denticles both in shape and density.   For example, Dromaeosaurus found in Campanian deposits is similar to those of tyrannosaurids, chisel shape. Dakotaraptor is narrow with a rounded end.    The last group of photos works for me, thanks, they are chisel shaped which is tyrannosaurid.     So the tooth is a tyrannosaurid and would lean toward a Nanotyrannus but cannot rule out T rex given the size.  

Wow, I never even considered Tyrannosaur. It's so little it must be a hatchling, that's really neat!

Thanks!

[Troodon]

Not necessarily it could be an unerupted tooth.   Hatchling teeth would be much smaller

[jikohr]

1 minute ago, Troodon said:

Not necessarily it could be an unerupted tooth.   Hatchling teeth would be much smaller

There's some pretty clear feeding wear, wouldn't that rule out unerupted?

[Troodon]

Not sure its feeding wear but hatchlings teeth would be a few mm.

[jikohr]

2 minutes ago, Troodon said:

Not sure its feeding wear but hatchlings teeth would be a few mm.

But definitely a very young juvenile though correct?

 

I'm just trying to picture a rex tooth that's only a few mm. I mean this one's less than 9 mm. 

[Troodon]

Here are a couple in my collection

[jikohr]

Wow, yeah those are pretty tiny.

Thanks for all the help man!