Hadrosaur Bone Fragment with Bite

[Bedrock]

Greetings, I have a bone fragment that's a mystery to me.

This fragment is part of a find that I had posted in another thread in 2019 showing a Dental Battery.

The dentary was presumed to be Edmontosaurus.

The pictures here are of a 5" fragment that I would like to identify the bone & placement, this fragment also has a penetrating bite.

The sediment that filled the bite area has been removed and the cavity seen in the pictures is from the bite.

Two curved teeth about 4" or more penetrated completely through, pushing a lower tooth down into bone while two smaller teeth were sheared away.

I've been unable to match this fragment with the other pieces I recovered and any assistance would be greatly appreciated.

I found this on private land with permission.

Rosebud County Montana.

[Sjfriend]

Will wait for others more knowledgeable but #3 looks like inside view of braincase to me 

[Troodon]

I wonder if this is part of the snout (Pre-Maxilla).  I dont believe the first big hole is a puncture since the bone continues down one of the edges.  The other hard to say not the shape I would expect from a Theropod tooth.

 

@LordTrilobite

[LordTrilobite]

Oof hard to say. I'd agree with Troodon that it doesn't exactly look like a bite mark. But I think don't that hole looks like a natural part of the bone originally.

[jpc]

this may also be part of the coronoid process of that same lower jaw you mentioned.  

[Bedrock]

I thought that was it until I remembered I had the damaged coronoid process packed away in another box, its about half the size of the piece I posted here and looks

like the circled pic below.

I reckon I'll keep searching for a match.

Thank you very much for helping, I know how difficult pictures can be to interpret vs a hand study.

Edited February 25, 2022 by Bedrock
I was mistaken

[Bedrock]

19 hours ago, LordTrilobite said:

Oof hard to say. I'd agree with Troodon that it doesn't exactly look like a bite mark. But I think don't that hole looks like a natural part of the bone originally.

I circled a picture locating were a third tooth punctured and grazed outward across the top, there are also three light grooves to the left.

A little history about the entire specimen I found:  The entire find was part of a limestone concretion that tumbled from a cliff wall into a wash and had broken up.

There were several small Baculites in the concretion with some of the bones having mudstone on one side giving the appearance that it lay in mud for a time and

was either washed out to sea or later inundated.

[Bedrock]

On 2/23/2022 at 1:58 AM, Sjfriend said:

Will wait for others more knowledgeable but #3 looks like inside view of braincase to me 

Here's another pic from some early work I did cleaning out the sediment.

I circled two smaller teeth that appear to have broken off and were sheared away inside by a larger tooth.

I thought these were muscle or tendon attachments before I dug in  a little deeper.

The lower tooth in the first picture is shown inside were it penetrated and was sheared away.

The third picture circled area is of a smaller tooth that penetrated and split the bone upward of the entry hole as did the large tooth

that entered on the right of it.

[jpc]

New info alert.  You found this in marine beds!!??  With Baculites??!!  That is cool and potentially unique.  In that case, your 'tooth' holes could just as well be from shipworms.  This may be the only hadrosaur specimen known from the MT Bearpaw Shale (which is my assumption based on baculites and Rosebud County).  (I think there is one reported form Canada from the Bearpaw).  If so, it is worthy of a museum donation.