Central Texas Crocodile

[erose]

A few weeks back the Paleontological Society of Austin went out on one of our monthly field trips.  The weather was still quite warm and we decided to keep it closer to home so no one would be to wrung out when we were done. We are hopefully at the tail end of a rather brutal drought with constant triple digit temps that started back in June. We picked three sites within 90 minutes of Austin that took us up thru the Glen Rose Formation, bottom to top.  We started at a site in the Lower Member known as the micro zone. Fossils big enough to see from a standing position are few but if you get down and crawl around you can be rewarded with a crazy variety of tiny echinoids, starfish and crinoids and other odd bits in amongst the usual molluscs.  The second site was at the very top of the Lower Member in the Salenia texana zone and folks found their share.  But it was the last stop way up in Unit 7 of the Upper Member that I found my keeper* for the day. 

 

I had collected this site over the years and knew it as good for small echinoids and on occasion ammonites. But I was going back with some fresh information provided by the local researcher William Rader. Bill Rader had informed me that the site produced vertebrate material including many years before a crocodile scute.  When we got there I spent time in the ammonite zone and helping others find fossils but it was at the tail end of the afternoon as I was thinking about the drive home that I moved to some lower layers that generally just produce common molluscs. AND BAM! Bones...  Now I just assumed they were turtle which isn't uncommon in the Glen Rose but always a good find. I found two of the pieces within inches and they fit together. Jamie Shelton was there and I called her over to help me scan the spot with an extra set of eyes. I found a third piece before we quit.

 

The next day was Identification Day at Texas Memorial Museum and PSA was manning the invertebrate table. But I knew there would be a few vertebrate specialists as well.  As the day wound down I found a moment to show them to Chris Sagebiel of UT. He wasn't quite sure at first but when I mentioned that croc material was known from the site he immediately thought that it was a match.  

 

* Chris asked what I was planning on doing with the specimen (nudge nudge) and I agreed it should go to the Vertebrate lab here at UT.

 

Here are some pics of the bones and a few from the day.

 

 

Edited October 6, 2019 by erose

[erose]

 

 

Here are some pics of the bones and a few from the day.

 

 

 

 

[erose]

A few more photos.

[JohnJ]

A significant and incredible find, Erich!  Hopefully you can add more to that assemblage.

[FossilDAWG]

Excellent find! 

Wish I lived closer.

 

Don

[Jeffrey P]

Congratulations Erich on an impressive find.

[erose]

3 hours ago, JohnJ said:

A significant and incredible find, Erich!  Hopefully you can add more to that assemblage.

 

1 hour ago, FossilDAWG said:

Excellent find! 

Wish I lived closer.

 

Don

 

20 minutes ago, Jeffrey P said:

Congratulations Erich on an impressive find.

Thanks folks. I was sort of flabbergasted finding out it was a crocodile bone. Apparently there was a small species that is known from other Glen Rose locations. This will add to the small list of known material. I am going to see if they can find the scute that William Rader deposited in the collection and get the specimens together.

 

The site is close to where I work and I will be able to visit it regularly. It is a large cut and will keep me busy for a while.

[PFOOLEY]

Definitely a keeper...excellent find, Erich. Good luck in your return visits...I hope you are able to recover more of that animal.

 

Are the turtles in the Glen Rose of the marine variety? Also, in the field photo of your find, what is the object in upper left? 

[erose]

2 hours ago, PFOOLEY said:

Definitely a keeper...excellent find, Erich. Good luck in your return visits...I hope you are able to recover more of that animal.

 

Are the turtles in the Glen Rose of the marine variety? Also, in the field photo of your find, what is the object in upper left? 

Thank you. I hope I can find more as well. But these were probably scattered bits at the time of deposition. 

 

Yes the turtles are marine and all in bits and pieces. I have a handful or two of plastron bits, a single vertebrae and a few ends of long bones but still not enough for any ID.

 

The "round" things above the bones are oysters. The strata has scattered little clumps of oysters. Probably two or three species at least.

[Pemphix]

Croc, humerus or femur.

Very nice ! Congrats !

[erose]

7 hours ago, Pemphix said:

Croc, humerus or femur.

Very nice ! Congrats !

Harry Pristis had posted some pics of similar cric/aligator femurs in an earlier related post. 

 

Vertebrate material, even shark and fish teeth, are rare in the Lower Cretaceous of the Texas Hill Country. Upper Cretaceous locals like the Sulphur River or Big Bend produce bones. But not so much these shallow marine carbonates of Central Texas.  Finding any teeth or bone is a bonus day.

[Fossildude19]

Great post and find, Erich. Congratulations!   

 

[Mark Kmiecik]

23 hours ago, erose said:

and I agreed it should go to the Invertebrate lab here at UT.

invertebrate ?

[erose]

46 minutes ago, Mark Kmiecik said:

invertebrate ?

Duh....thanks for catching that....

[Mark Kmiecik]

4 minutes ago, erose said:

Duh....thanks for catching that....

Yeah, us invertebrate guys would probably still trying to figure out which species of bryozoan we're looking at. 

[Uncle Siphuncle]

Well done, Erich.  My best Texas croc matl is Eocene.  

[Al Tahan]

Killer find!!  

[Plantguy]

Nice finds! Regards, Chris 

[erose]

Some more bone material from this site.  Pretty sure this one is turtle. One of the larger turtle fragments I have found in the formation.

 

[erose]

one more pic...the always necessary end view...

[LSCHNELLE]

Erich:  Great find and nice contribution to science. [Apparently, you need to be careful WHO you ask for a fossil ID and WHERE you are when you are asking.]  Maybe, you are becoming more of a vertebrate fossil hunter!  I can help you with that. Haha! 

[HemiHunter]

Cool story and cool find!

[jpc]

excellent tale.  My ommdeiate imprssion was humerus, but I will have to look in my fied guide.

[gms]

Nice croc femur. Congrats!

[Harry Pristis]

On 10/6/2019 at 8:59 AM, erose said:

Harry Pristis had posted some pics of similar cric/aligator femurs in an earlier related post. 

 

Vertebrate material, even shark and fish teeth, are rare in the Lower Cretaceous of the Texas Hill Country. Upper Cretaceous locals like the Sulphur River or Big Bend produce bones. But not so much these shallow marine carbonates of Central Texas.  Finding any teeth or bone is a bonus day.

 

Certainly looks crocodile: