White River Skull Prep

[LordTrilobite]

I recently got this skull as a fun prep project. I bought it as a Hyaenodon skull from North Western Nebraska. But I quickly noticed that it was likely something else. I don't have a whole lot of experience with carnivorans but I think it might be a nimravid based on the number and placement of the teeth. Hoplophoneus or Dinictis maybe? It's missing its fangs and all the front teeth but otherwise it's in general good shape.

 

I've already removed a whole lot of material. And it's starting to look like something. There is very little crushing and the bone is quite well preserved. But there is a break in the middle of the skull. So I fear some bone might not be in the best shape under the matrix there.

Fossil as arrived with a bunch of matrix  on it. Especially the left side had a lot of material on it and seems a little better preserved than the right side.

 

 

After the first big prep session.

 

 

And the most recent state with again a whole lot of material removed. It seems that sadly the jugal isn't as intact as I had hoped.

[snolly50]

That's a great project, have fun!

[Ludwigia]

Looks like fun!

[Fossildude19]

Looking good, m'lord !   

[ParkerPaleo]

Looks like a cool project!

 

Can you prep out the molar/s behind the carnassial?  It looks very dog-like to me.  I'd start by comparing to Mesocyon.

 

It doesn't look like you have alot of the ear regions preserved but that can be fairly diagnostic as well.

[PrehistoricWonders]

I’m not extremely familiar with White River, but I don’t believe it’s Hyaenodon. It’s could be some other Canid-like species, or otherwise, I’d agree with cat. The Tooth I can see looks canid too me, but I’m not positive.

 

Oh, by the way - great prep so far! Looks awesome.

[LordTrilobite]

Thanks all!

5 hours ago, ParkerPaleo said:

Looks like a cool project!

 

Can you prep out the molar/s behind the carnassial?  It looks very dog-like to me.  I'd start by comparing to Mesocyon.

 

It doesn't look like you have alot of the ear regions preserved but that can be fairly diagnostic as well.

 

2 hours ago, Familyroadtrip said:

I’m not extremely familiar with White River, but I don’t believe it’s Hyaenodon. It’s could be some other Canid-like species, or otherwise, I’d agree with cat. The Tooth I can see looks canid too me, but I’m not positive.

 

Oh, by the way - great prep so far! Looks awesome.

 Yeah I did look at some doggos. Mesocyon included. They seem to show some similarities. But the tooth count is off. On the skull I have 3 premolars. All the dog and dog-bear examples seem to have more premolars. The canine teeth are gone, but their sockets are still pretty well preserved. I will definitely try and see what's behind the premolars that are already visible. It seems like at least on the right side this part might be destroyed. I'm hoping the ear and jaw joint area is better preserved.

[ParkerPaleo]

15 hours ago, LordTrilobite said:

Thanks all!

 

 Yeah I did look at some doggos. Mesocyon included. They seem to show some similarities. But the tooth count is off. On the skull I have 3 premolars. All the dog and dog-bear examples seem to have more premolars. The canine teeth are gone, but their sockets are still pretty well preserved. I will definitely try and see what's behind the premolars that are already visible. It seems like at least on the right side this part might be destroyed. I'm hoping the ear and jaw joint area is better preserved.

Enhydrocyon has a reduced premolar count.  That would be interesting!

 

Check for literature/illustrations from Wang and Tedford if you don't already know.

Edited March 31, 2021 by ParkerPaleo
adding info

[LordTrilobite]

Hm... That Enhydrocyon does actually show some similarities. I don't think I came across that one before.

 

Diagram of Enhydrocyon from Wikipedia for reference. The back of the braincase seems to be a little different though.

 

Here's also some more prep progress. Again, I've removed a lot of excess material. But I've also gotten part of the ear and jaw hinge areas a bit cleaner. The left side is a little better preserved than the right. No molars yet tho.

 

[ParkerPaleo]

There are some other genera in that clade as well, so Enhyrdocyon may not be the exact one.  I'll have to find the descriptions/papers (still packed away from last time I moved).  I think I have some reference material in the collection here too.  Prep is looking good so far though.

 

The preservation/matrix reminds me of the Leptauchenia zones, I'd imagine this came from high in the section, Whitney/Sharps/Arikaree.  

[LordTrilobite]

3 hours ago, ParkerPaleo said:

There are some other genera in that clade as well, so Enhyrdocyon may not be the exact one.  I'll have to find the descriptions/papers (still packed away from last time I moved).  I think I have some reference material in the collection here too.  Prep is looking good so far though.

 

The preservation/matrix reminds me of the Leptauchenia zones, I'd imagine this came from high in the section, Whitney/Sharps/Arikaree.  

Thanks that would be most helpful. Sadly I don't have a very precise location besides Nw Nebraska Miocene 15 to 20 mlj.
The matrix is fairly hard and quite dusty. There are pockets of softer matrix that seem like dried mud. It's similar to the matrix on a Stylemys turtle I have. It seems completely colourless too. I have a rhino skull from the White River fm as well, but that has matrix with a slight pink tint to it.

[Kiros]

So you were the one who bought it! I thought alot about buying it, but it was definitely outside my budget

[LordTrilobite]

Some more progress. I've cleaned much of the bottom of the braincase by now. Although I didn't take a picture of that this time. It seems more and more that the skull fits most with dogs. So Enhydrocyon is still a likely candidate. There's still some way to go, but I might just leave some of the matrix in place for stability sake.

 

[LordTrilobite]

Some more progress. This time with water! While the matrix is quite hard. Some areas do get a little softer with water. It also creates really good contrast that makes identifying bone next to matrix easier. I tried brushing with a wet toothbrush before at a smaller scale to try it out. There didn't seem to be any negative effects so I did a whole prep session where I kept the whole fossil wet.

Click to enlarge.

 

[Ludwigia]

Now we're really getting somewhere!!

[hadrosauridae]

Looking great!

[PrehistoricWonders]

Any updates? Looked awesome at the last update, would love to see it now!

[LordTrilobite]

Sorry, I haven't worked on this skull much in the mean time. Been busy with other projects. But I will definitely post more when I have an update.

[LordTrilobite]

Finally some progress! I've been working on the remaining area between the teeth and I made some good progress. Sadly it seems like the molars are completely gone.

 

And a few hours and a water rinse later.

 

 

I still want to completely prep the teeth free. But I will likely leave some of the matrix in the middle of the skull alone for stability.

[jpc]

if it makes you feel any better these things did not have much for molars.  That last premolar is the business end of the mouth.  

[LordTrilobite]

13 minutes ago, jpc said:

if it makes you feel any better these things did not have much for molars.  That last premolar is the business end of the mouth.  

So you know which species it is then? I had some ideas but did not have a definite ID yet, as I was still prepping.

[PrehistoricWonders]

Great work! Can I see a pic of the upper P4 Carnassial? Based off the pics I’d say Canid, but I’d like too see a closeup to confirm.

[jpc]

9 hours ago, LordTrilobite said:

So you know which species it is then? I had some ideas but did not have a definite ID yet, as I was still prepping.

I don't.  Sorry.  I have Scott and Jensen's tome on the White River Fauna, but noy here at home.  PM me to remind me and I will look it up in a few weeks.  

[LordTrilobite]

13 hours ago, Familyroadtrip said:

Great work! Can I see a pic of the upper P4 Carnassial? Based off the pics I’d say Canid, but I’d like too see a closeup to confirm.

Thanks! I mean, there are closeups of all the preserved right here. Have you clicked on them to enlarge the photos?

 

8 hours ago, jpc said:

I don't.  Sorry.  I have Scott and Jensen's tome on the White River Fauna, but noy here at home.  PM me to remind me and I will look it up in a few weeks.  

Ah okay, thanks! I will.

[PrehistoricWonders]

3 hours ago, LordTrilobite said:

Thanks! I mean, there are closeups of all the preserved right here. Have you clicked on them to enlarge the photos?

Oh, my bad. Didn’t realize I could enlarge the picture. 
Definitely looks Canid! Nice find/buy!