Jump to content

Ramon

Recommended Posts

Hello, this spring break I found this vertebra in late Campanian sediments from southern Coahuila, Mexico. It comes from the Late Campanian, Cerró del Pueblo Formation, around 73-71 million years. This was found along with marine and terrestrial fossils. It is about 1 cm long (3/8) of an inch, 1 cm in width, and 1.1 cm in height. I want to know what type of dinosaur this vertebra belonged to and whether it’s a caudal vertebra or not. My thoughts on this specimen at the moment, is that it’s probably a caudal (tail) vertebra from a small theropod dinosaur, something like a dromeosaur or a troodontid. I hope some dinosaur experts on this forum can give me more insight on this small vertebra..

 

 


Side view61A0EEC8-0C69-4DD0-A2BD-A94C1FA83B22.thumb.jpeg.47498d0a8c793f806fb909f892cf3349.jpeg

 

Other side

ED8D4253-544B-4A23-AA7B-6ACA6C4529F1.thumb.jpeg.70763cc6ebdf0814b0a489ea764c1cb0.jpeg

 

Front view
F3D78C8E-5C81-456C-A1A4-F4F5E8CB056D.thumb.jpeg.17f77b84d0d1ff01b92fc411d95a7d42.jpeg
 

 

Bottom

ADD25984-7122-4712-B38A-4804AE57286F.thumb.jpeg.11930a184c06dc3747aa15318607a43b.jpeg
 

Top view7B8661E6-8669-4141-AA27-6F76DF2D20D4.thumb.jpeg.f049ae9ceba68a2343613d7b600fd5bd.jpeg

F02D9A95-8E51-463B-9141-50B0BCF6D214.jpeg

  • I found this Informative 3

 

"Without fossils, no one would have ever dreamed that there were successive epochs in the formation of the earth" - Georges Cuvier

Link to comment
Share on other sites

2 minutes ago, Troodon said:

Looks like a caudal vertebra from an indeterminate hadrosaurid. 


Wow, I would’ve never thought this came from a hadrosaur given the small size of the specimen. Could it be from an infant hadrosaur?
 

What are the differences between hadrosaur and theropod caudal vertebrae? 

 

"Without fossils, no one would have ever dreamed that there were successive epochs in the formation of the earth" - Georges Cuvier

Link to comment
Share on other sites

I have small ones in my collection.  Distal Caudals can get quite small and yes most likely a juvie.  Hadro centrums have a rectangular cross section and are boxey...not typical of theropod.

  • I found this Informative 3
Link to comment
Share on other sites

What about the Pleurocoels? 
“Saurischian dinosaur vertebrae sometimes possess features known as pleurocoels, which are hollow depressions on the lateral portions of the vertebrae, perforated to create an entrance into the air chambers within the vertebrae, which served to decrease the weight of these bones without sacrificing strength.”


- Martin, A.J. (2006). Introduction to the Study of Dinosaurs.

 

 

Caudal vertebra of the theropod Aerosteon riocoloradensis showing pleurocoel (pl) and a smaller septum (se)

853334B8-EECE-4587-A203-558F79BD256F.jpeg.b11d1bab184cf749ae051f5aaa8301f8.jpeg

Photograph from “Evidence for Avian Intrathoracic Air Sacs in a New Predatory Dinosaur from Argentina”

 

 

My vertebra

ADA3D282-8CB8-4018-9AB6-A75DCFD1DA2F.thumb.jpeg.2e71b98ab072dec199d4da07abd41215.jpeg
 

 

I haven’t found any literature on other dinosaur groups other than theropods having Pleurocoels. What are y’alls thoughts on this?

 

  • I found this Informative 1

 

"Without fossils, no one would have ever dreamed that there were successive epochs in the formation of the earth" - Georges Cuvier

Link to comment
Share on other sites

I do not believe those are pleurocoelus, tendon attachment points.  "Pl" are typically larger and oval like the one in your illustration 

  • I found this Informative 3
Link to comment
Share on other sites

9 minutes ago, dinosaur man said:

Cool find :thumbsu:

 

Thanks!! It’s the first dinosaur fossil I’ve found. Ever since I was a kid I’ve been fascinated by these creatures, and I’m very happy I finally found something interesting.

  • I found this Informative 1

 

"Without fossils, no one would have ever dreamed that there were successive epochs in the formation of the earth" - Georges Cuvier

Link to comment
Share on other sites

3 minutes ago, Ramon said:

 

Thanks!! It’s the first dinosaur fossil I’ve found. Ever since I was a kid I’ve been fascinated by these creatures, and I’m very happy I finally found something interesting.

Agreed dinosaurs are amazing creatures!!

  • I found this Informative 1
Link to comment
Share on other sites

yes, hadrosaur.  Adult.  I have seen a noce articulated hadrosaur tail, and the vertebrae get very small in the end.  So yes, any size can be an adult animal.  

  • I found this Informative 2
Link to comment
Share on other sites

44 minutes ago, jpc said:

yes, hadrosaur.  Adult.  I have seen a noce articulated hadrosaur tail, and the vertebrae get very small in the end.  So yes, any size can be an adult animal.  


Thanks for the information!! :)

 

"Without fossils, no one would have ever dreamed that there were successive epochs in the formation of the earth" - Georges Cuvier

Link to comment
Share on other sites

I agree with Troodon and Jpc. Typical Hadrosaur caudal vert.

 

 

Here's an Edmontosaur caudal vert from my collection for reference. Though it's a little more subtle on your specimen, notice the hexagonal shape of the centrum.

  • I found this Informative 2

Olof Moleman AKA Lord Trilobite

Link to comment
Share on other sites

I know this vertebra’s owner has been identified as a hadrosaurid, but I have one more question. Could the holes in the vertebra be from predation/scavenging? I have been reading on this hadrosaur caudal vertebra from Coahuila, Mexico. It has a hole which is a result from predation by a Deinosuchus crocodile. 
 

My specimen 
8C163AE4-3397-4871-A010-05D251485856.thumb.jpeg.efccc07807c92a17bab72a60940b1eef.jpeg

 

 

E05A6EDC-6A71-43BE-9477-68F96F7D1BAE.jpeg.a99ae1a061b2cbb56b70d403d52bceb5.jpeg

  • I found this Informative 1

 

"Without fossils, no one would have ever dreamed that there were successive epochs in the formation of the earth" - Georges Cuvier

Link to comment
Share on other sites

look for the semi lunar crushing marks.  Its a shame the photo of the Mexican bone are note bigger so that we can see what the authors are talking about.  Google it, maybe

  • I found this Informative 2
Link to comment
Share on other sites

It’s hard to know what the authors are talking about. I took closer pictures of the 2 largest puncture holes. The largest one is 1.5 mm long and about 2nmm deep. They are small compared to other bite marks I’ve seen. What do you guys think? Could it have been made by some small scavenger?

 

 

Largest puncture hole
F9AC260F-BD6A-43D4-ACBF-7E1A55A3479C.thumb.jpeg.7def347472a7d431affcdb59c88c06f1.jpeg
ED9C0AC9-0F1E-4DA0-80F7-CD968FC33CA8.thumb.jpeg.906d98d2537e7ff30c01b74ee332bf7e.jpeg
 


 

 

  • I found this Informative 1

 

"Without fossils, no one would have ever dreamed that there were successive epochs in the formation of the earth" - Georges Cuvier

Link to comment
Share on other sites

4 hours ago, Ramon said:

I know this vertebra’s owner has been identified as a hadrosaurid, but I have one more question. Could the holes in the vertebra be from predation/scavenging? I have been reading on this hadrosaur caudal vertebra from Coahuila, Mexico. It has a hole which is a result from predation by a Deinosuchus crocodile. 
 

My specimen 
8C163AE4-3397-4871-A010-05D251485856.thumb.jpeg.efccc07807c92a17bab72a60940b1eef.jpegE05A6EDC-6A71-43BE-9477-68F96F7D1BAE.jpeg.a99ae1a061b2cbb56b70d403d52bceb5.jpeg

Notice that the example I posted from my collection also has a little hole on the left side, bottom half. It's probably just a blood vessel opening or nutrient foramen or something like that. The size and shape varies quite a bit between vertebrae and individuals as well.

I do not think these are predation marks. They look rounded and natural imo.

 

I don't think those holes are particularly odd or anything. Seems perfectly normal to me.

  • I found this Informative 2

Olof Moleman AKA Lord Trilobite

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...