Theropod Toe Bone

[Dino Dad 81]

Hey all,

 

What do you think of this toe bone from Hell Creek? The seller marked it as Saurornithelestes with a "?" at the end. It's a tiny 0.5".

 

What I thought might be diagnostic about it is the proximal end. I believe it has Toe 2 Digit 2 characteristics. But it also looks like the flatter top part of the proximal end (bottom part in this picture) may just be worn down or something--it doesn't look totally smooth. If you think there's anything to the Toe 2 Digit 2 hypothesis, then I assume it's theropod indet rather than Saurornithelestes--or is there a case for young Acheroraptor? For all I know, you'll think the proximal end simply has wear to it and it's not even from an animal with a sickle claw.

 

Thanks,

 

 

 

Edited February 11, 2022 by Dino Dad 81

[Troodon]

With that proximal end my guess its Digit I -1 of some indeterminate theropod and definitely not Saurornitholestes.  Could be Acheroraptor or a Troodontid but being so small other possibility occur.  Nice phalanx.

[Nanotyrannus35]

The seller did also state that it was a dromaeosaurid theropod bone with Saurornitholestes in parentheses.

[Dino Dad 81]

On 2/11/2022 at 3:35 PM, Nanotyrannus35 said:

The seller did also state that it was a dromaeosaurid theropod bone with Saurornitholestes in parentheses.

 

@Troodon, the plot thickens. I had the pleasant surprise of finding out when it arrived today that the 0.5" measure must have been a width, because the specimen is about 1" long.

I've lined it up with casts I have of Velociraptor Toe 2--not because I'm suggesting this is a Toe 2, only because they're the only remotely relevant casts I have (even if just for size comparison). What do you think I've got here?

 

 

 

 

 

 

 

 

A deeper dive into the proximal end, to see if you think wear/damage could have meaningfully affected the shape.

 

Thank you!!!

 

[Troodon]

Isolated toe bones are very hard to diagnose.  Here is the foot of Saurornitholestes

Digit II -2 is not similar to yours

 

Here you can see digit I-1 which I think is a better match not perfect but better.

Lots of small theropods in the HC that it could fit.

 

[Dino Dad 81]

@Troodon

Saurornitholestes itself I figured was not correct and, as @Nanotyrannus35 pointed out, the seller's ID was primarily just dromaeosaurid. Do you think it's safe to assume it was a dromie or troodontid?

 

Thanks again,

[Troodon]

Thats what I previously said its not Saurornitholestes just using that as a better comparison than the one you used.  I dont know what it belong to but like I said above Acheroraptor or a Troodontid is a possibility but there are lots of other small theropod around.  We have no direct comparative material to use

[Dino Dad 81]

Thanks, Frank. I understood your use of Saurornitholestes and you're the main reason I work off the assumption that we can't treat Saurornitholestes as a resident in  the HCF (I'd just be confused by it all if not for you). I just wanted to see if, while broadening the pool of candidates, we could keep it to something with teeth and a sickle claw. Oh well..

 

Thanks, again.

Edited February 14, 2022 by Dino Dad 81

[Fullux]

On 2/14/2022 at 5:18 PM, Dino Dad 81 said:

 

I have a phalanx that looks very similar to yours. I did two days worth of digging and managed to match it with ornithomimids, Here is the phalanx I have and the foot bones of an ornithomimid from Mongolia that I used for comparison.

Edited January 24, 2023 by Fullux

[Dino Dad 81]

1 hour ago, Fullux said:

I have a phalanx that looks very similar to yours. I did two days worth of digging and managed to match it with ornithomimids, Here is the phalanx I have and the foot bones of an ornithomimid from Mongolia that I used for comparison.

 

Thanks, @Fullux, but I'm not sure I see much similarity between the proximal end of the phalanx I posted and the proximal end of the one you posted (which is missing/damaged) or those of the Mongolia ornithomimids.

[Troodon]

Here are the ornithomimid foot from the Scollard equivalent to the Hell Creek.  Not seeing any similarity.   Isolated Toe bones are very difficult to ID.   Still think it's might be Dromaeosaurid.