Interesting Hell Creek Vertebra

[PaleoNoel]

Hi everyone, I found this little, mostly complete vertebra in the Hell Creek formation of South Dakota in 2019. I don't really know what to make of it as it's very porous, and amphiplatyan (flat on both sides), although I'm not sure how much of that could be attributable to wear. I believe it's safe to cross of squamate (due to lack of concavity) and champsosaur (overall shape) off the list. While most of the crocodilian verebrae I have found in the hell creek have have a convex and concave end, I am aware that some can be found that are flat sided. The porosity of the bone makes me hopeful that it's theropod, but am not by any means discounting mammal, croc or any other possibility. Dimensions are 1 cm in length, .8 cm in height from base to the end of the process and about 1.2 cm. I would like to know the opinions of my fellow members.

 

[Troodon]

Interesting not dinosaurian or champsosaur 

[PFOOLEY]

Very interesting. What do you think about the possibility of it being from a Pterosaur?

 

The Evolution of Pneumatic Foramina in Pterosaur Vertebrae

[PaleoNoel]

1 hour ago, PFOOLEY said:

Very interesting. What do you think about the possibility of it being from a Pterosaur?

 

The Evolution of Pneumatic Foramina in Pterosaur Vertebrae

That would be awesome! I'll look into it.

[PaleoNoel]

@jpc what do you think? Ever come across a vert like this? I looked at the paper @PFOOLEY shared and I saw some similarities between the more derived pterosaur verts and my own.

[jpc]

I do not know.  I don't think it is flat on both ends; it is broken and only half of it is there.  It could certainly  be bird or pterosaur, both extremely rare in the Lance/HC.   Good eye.  Can we see a 3/4 view of the one articular end?  

[PaleoNoel]

41 minutes ago, jpc said:

I do not know.  I don't think it is flat on both ends; it is broken and only half of it is there.  It could certainly  be bird or pterosaur, both extremely rare in the Lance/HC.   Good eye.  Can we see a 3/4 view of the one articular end?  

Unfortunately I'll be away from my collection for a few months as I'm at school. If I can remember to come back to this thread when I get back I will post different and hopefully clearer angles.

[PFOOLEY]

On 2/22/2021 at 11:22 AM, PaleoNoel said:

...when I get back I will post different and hopefully clearer angles.

 

[PaleoNoel]

On 7/30/2021 at 3:03 AM, PFOOLEY said:

 

Thanks for the reminder. I took a couple more shots of it before I went on my trip last month so here they are.

 

[PaleoNoel]

Circling back to this thread.

I was flipping through Weishampel et.al.'s The Dinosauria 2nd Edition and my eye was caught by these verts from Troodon formosus. I saw some similarities here, but also with pterosaurian verts.

https://www.researchgate.net/figure/Pneumatic-foramina-in-pterosaur-vertebrae-a-Pneumatic-foramina-on-the-lateral-surface_fig1_332892571

 

[jpc]

That is a great find, but I am no closer to putting a name on it.  It certainly has a bird/pterosaur look to it.   It is a gestalt thing.  Other then the pneumaticity, I cannot say why I feel b/pt.