Possible Ankylosaur or Nodosaur Osteoderm

[Nanotyrannus35]

I have this piece of bone that due to the texture and shape I think might be an ankylosaur osteoderm. It also seems like it might have some predation, shown by the circled area. It's from the Lance fm of Weston Co. WY. Thanks for any help.

[Troodon]

Can you provide a better infocused shot of your last photo and a closeup of the blue area

 

That could be a puncture, looks right

[Nanotyrannus35]

1 minute ago, Troodon said:

Can you provide a better infocused shot of your last photo and a closeup of the blue area

 

That could be a puncture, looks right

I'll be able to get a picture of that later today.

[Dino Dad 81]

Wow, is it an Ankylosaur osteoderm, @Troodon?

[Nanotyrannus35]

7 hours ago, Troodon said:

Can you provide a better infocused shot of your last photo and a closeup of the blue area

 

That could be a puncture, looks right

Here you go

 

[Troodon]

Thank you.  I'm seeing the 3D fibers in the external cortex in that last image.  Thats a characteristic of a Nodosauridae osteoderm.  So good chance it's one. 

[Dino Dad 81]

Hi @Troodon,

I was lucky enough to get this specimen in a trade with nano. In seeing it with my own eyes, I'm wondering if there's a second potential puncture.

 

 

 

You can also see the cracking around the punctures. This osteoderm has no such cracks anywhere else.

 

[Dino Dad 81]

@jpc do you have any thoughts on this? Thank you!!

[jpc]

I would shy away from calling it an osetoderm.  I have seen this texture on frill pieces as well.  The continuous one-inch thickness suggests to me frill piece.  

[Dino Dad 81]

Thanks, @jpc.

 

I don't think it's likely frill, because there's only one side that broken:

 

Also, did you see @Troodon's comments on seeing the 3D fibers in the external cortex that's a characteristic of a Nodosauridae osteoderm?

 

Any thoughts on the second potential puncture?

 

Thanks,

 

[Troodon]

The finished edges on all sides but one suggests it's not frill.   I would expect a puncture would have sharpe edges all around and more uniform, so I would lean against it being one but who knows.

[doushantuo]

some of you may like:

HISTOLOGY OF ANKYLOSAUR OSTEODERMS: IMPLICATIONS FOR SYSTEMATICS AND FUNCTION
TORSTEN M. SCHEYER and P. MARTIN SANDER 

Journal of Vertebrate Paleontology 24(4):874–893, December 2004

size: 2,33 MB,approximately

 

1987596961_ScheyerSander2004AnkyloHistoJVP(1).pdf

[jpc]

Devil's advocate says: The 'finished' edges could just as well be waterworn.  There is so much water worn bone in the Lance.  

 

[Dino Dad 81]

I say this as a novice compared to you two, but I've never seen any frill that looks like this. There aren't any signs of the veininess that runs well below the surface on most pieces. I've gone through about 100 pounds of sedmient from this source in Weston, WY and have several dozen pieces like the group I show at the bottom that seem much more likely to represent worn frill.

 

 

 

 

 

 

[jpc]

If I can find a piece of frill with that texture in the next few days, I will send a photo.  

 

 

[Dino Dad 81]

I believe it!

I'm just saying, in terms of leaning one way or another, between it having 3 finished sides and it not showing some of the key diagnostic features of frill, I'd think Nodosaur is the higher confidence level. Also, can it maintain this level of texture if there was such substantial water erosion?

[Carl]

I agree that osteoderm is a strong possibility but that waterworn frill fragment should not be ruled out. But more important to me: THANKS FOR SAYING OSTEODERM!!!

[jpc]

Oh, Carl... that's cute.  

 : )

 

 

[Carl]

24 minutes ago, jpc said:

Oh, Carl... that's cute.  

 : )

 

 

Cute that I'm a hopeless optimist?

[jpc]

2 hours ago, Carl said:

Cute that I'm a hopeless optimist?

cute as in 'scute'

[Carl]

1 hour ago, jpc said:

cute as in 'scute'

HAAAAAAAAAAA!!!!!! Genius...

Edited May 9, 2023 by Carl

[jpc]

30 minutes ago, Carl said:

HAAAAAAAAAAA!!!!!! Genius...

got ya.  you know what else is cute?  Coots. 

 

This post has been interrupted by an osteoderm/scute malarkey.  back to your regularly scheduled program. 

 

 

[Dino Dad 81]

Do these help diagnose? Help on puncture?

 

 

 

 

 

 

[Dino Dad 81]

Hi @Troodon @jpc and @Carl,

 

I added some pics above and some below too. Please see the ones below in daylight. Does this texture and the unbroken edges seal the deal?

 

 

 

 

 

[Troodon]

No change from my original comments.