I'm stumped--large quadraped partial ilium?

[Brandy Cole]

So my husband found this heavily mineralized bone while we were hunting in southeast Texas with @Lorne Ledger.  Mostly Pleistocene age material in the area.

 

It was too dirty to identify then.  I've cleaned it up, and I've been struggling to ID it.  It has a large, thick base but dramatically thins toward the outside (similar to how a scapula would, but I'm not sure it's the right shape for one.)

 

So far my best guess has been a partial ilium to a large quadraped since there aren't many bones that flatten out like a fan in that way.

 

I've included a picture of a wooly rhino ilium off a sales site first, not to argue it as a possibility, but as an example of the general similarities to a large ilium that I noticed in shape.

@JohnJ @Lorne Ledger @garyc@darrow@Shellseeker@Harry Pristis @digit

 

Any help would be fantastic.

Thank you,

Brandy

[Brandy Cole]

Here are a couple more pictures where I try to show the thickness of the fanned out portion.

[JohnJ]

Not saying it is, but look into the sloth limb bones....

[Brandy Cole]

4 minutes ago, JohnJ said:

Not saying it is, but look into the sloth limb bones....

Thank you.

 

I've actually looked in that direction over the past week or so since sloth bones do seem to have a lot of weird flares on the sides, but I haven't seen anything yet that screamed out that it was similar.  Do you know of any good resources for examples?  Online it seems I can only find pictures of complete skeletons which can make it hard for me to compare.

 

Thank you!

Edited October 11, 2021 by Brandy Cole
For clarity

[Brandy Cole]

When I was thinking ilium, I assumed that the thick side would have attached to the rest of the pelvis and that it has just broken off.

 

But if the thick ends are actually mostly intact articulation points instead of broken pieces worn down, then that would support the idea that it's a complete bone instead.

 

More pics of the end/articular surface...

[Lorne Ledger]

I don't know of any rhino material found on the river, but anything is possible.  I am not getting any vibe on any particular animal with that piece - but it is something big, in the size range of a big sloth or elephant, or a really big camel.  Sorry, will keep thinking on it.

[Brandy Cole]

On 10/17/2021 at 2:23 AM, Lorne Ledger said:

I don't know of any rhino material found on the river, but anything is possible.  I am not getting any vibe on any particular animal with that piece - but it is something big, in the size range of a big sloth or elephant, or a really big camel.  Sorry, will keep thinking on it.

I read a geological survey paper from 1912 about this area that said 'rhinoceros aceratherium' may be found near here due to upriver exposures of the formations underlying Lissie gravel and Beaumont clay.  I think I figured out by reading later surveys that it was an early attempt to reference aphelops.  

 

Definitely not saying that's what it is.  I just agree with you that it's obviously from something large, and I can't really find any examples of bones from large mammals that match the way it narrows down so fast into a plate.  The flatter part reminds me of scaphoid or pelvis, but nothing from the normal animals I look at seems to fit.

 

Thanks for looking though! 

 

--Brandy

[DPS Ammonite]

See this Journal of Paleontology article. It is available for free thru JStor.

Prothero, D., & Manning, E. (1987). Miocene rhinoceroses from the Texas Gulf Coastal Plain. Journal of Paleontology, 61(2), 388-423. doi:10.1017/S0022336000028559

 

https://www.jstor.org/stable/1305331?seq=1#metadata_info_tab_contents

[Brandy Cole]

Hey all,

I have an update for this one.

 

I got to visit the Vertebrate Paleo Lab at UT this week, and the lab manager was kind enough to take a look at some things for me.

 

He suggested sternum bone, and it compared pretty well with proboscidean sternum.

 

@JohnJ Is there a way to add sternum and proboscidean to the post tags?

 

 

[JohnJ]

28 minutes ago, Brandy Cole said:

@JohnJ Is there a way to add sternum and proboscidean to the post tags?

Done.

 

It's great you got to visit the VPL.  Who did you speak with?  Did you get any reference photos of their sternum specimens?  

[Brandy Cole]

11 minutes ago, JohnJ said:

Done.

 

It's great you got to visit the VPL.  Who did you speak with?  Did you get any reference photos of their sternum specimens?  

Thanks!

 

Kenny Bader showed us around.  Unfortunately I didn't think to get a picture of the comparison example they brought down. I think he said the one he used for comparison was modern elephant. The general shape was consistent with mine, but mine was more robust.  The attachments for ribs and the fan type tapering were roughly the same.  He said giant sloth could still be a possibility.  I don't think they had any sloth sternum at hand to compare it to.

 

We didn't have a lot of time, but he graciously looked at several of my finds that I hadn't been able to ID yet.  I'm looking forward to going back some time when I can spend more time touring the lab and taking pictures.  It was a great trip though.

Edited November 20, 2021 by Brandy Cole
Corrected description