How do I tell pterosaur hollow bones from dinosaur hollow bones?

[jikohr]

Hi everyone!

 

How do I differentiate cretaceous hollow bones from Morocco from being Pterosaur or something else like raptor or theropod? Here's a few hollow bones I'm working with right now, if e could provide some insight on differentiating them I'd really appreciate it. I think all but the one in the lower middle is Pterosaur since it has really thick bone walls.

[pachy-pleuro-whatnot-odon]

From what I understand pterosaur bones are paper-thin, thinner even than the specimens you have here. Overall bone shape would be another good indicator of a bone's origin. However, as I'm not that versed in pterosaur material, it might be good to ask @msantix and @FF7_Yuffie for their input.

[Troodon]

Like its been said bone thickness coupled with shape. I looked at a small Azhdarchoid from North America and the histology on this bone had a wall thickness around 1 mm.   We should also expect larger Pterosaurs to be a bit thicker.  The shape is also important because you might be looking at bird bones.   I also believe different sketal bones would be a bit different wing versus leg bones

 

A small azhdarchoid pterosaur from the latest Cretaceous, the age of flying giants (2016)

Elizabeth Martin-Silverstone, Mark P. Witton, Victoria M. Arbour and Philip J. Currie

 

 

 

 

[jikohr]

12 minutes ago, Troodon said:

Like its been said bone thickness coupled with shape. I looked at a small Azhdarchoid from North America and the histology on this bone had a wall thickness around 1 mm.   We should also expect larger Pterosaurs to be a bit thicker.  The shape is also important because you might be looking at bird bones.   I also believe different sketal bones would be a bit different wing versus leg bones

 

A small azhdarchoid pterosaur from the latest Cretaceous, the age of flying giants (2016)

Elizabeth Martin-Silverstone, Mark P. Witton, Victoria M. Arbour and Philip J. Currie

 

 

Here iscanotber

 

so oval shape cross section with a bone wall 1 mm or less is a possible Pterosaur?

The second and third fit that, the photos are soso and make the bone walls look thicker than they are but I just measured and those two have a bone wall less than 1 mm. 

The first one is interesting in that the cross section looks a lot like that one you posted where the ends of the oval are thicker, about 2mm but the rest is about 1 mm.

the fourth is very thick

the fifth is 2.5 mm all around 

the last and smallest is 1mm thick but the bone is very small.

 

[belemniten]

I am sorry but I cant really help you with your initial question but I took some pictures of my pterosaur bone cross sections. All are from the lower jurassic of southern Germany. I have the advantage that I dont have to distinguish between pterosaur and theropods, as theropods arent found here. 

They are perhaps good as a comparison, although the pictures arent great (they are quite small).

 

 

This one is quite compressed:

 

 

 

 

[pachy-pleuro-whatnot-odon]

1 hour ago, belemniten said:

I am sorry but I cant really help you with your initial question but I took some pictures of my pterosaur bone cross sections. All are from the lower jurassic of southern Germany. I have the advantage that I dont have to distinguish between pterosaur and theropods, as theropods arent found here. 

They are perhaps good as a comparison, although the pictures arent great (they are quite small).

 

 

Wow! Those are awesome specimens, Sebastian! Pterosaur material from the Posidonia Shale is so rare...!

 

But, yeah, no risk of confusion with theropod material in a marine context

Edited February 10, 2022 by pachy-pleuro-whatnot-odon

[belemniten]

17 minutes ago, pachy-pleuro-whatnot-odon said:

 

Wow! Those are awesome specimens, Sebastian! Pterosaur material from the Posidonia Shale is so rare...!

 

But, yeah, no risk of confusion with theropod material in a marine context

Thanks  

Yeah they are quite rare but I found much more Pterosaur material than Plesiosaurus material for instance. They must have gone fishing very often  

[pachy-pleuro-whatnot-odon]

Just now, belemniten said:

Yeah they are quite rare but I found much more Pterosaur material than Plesiosaurus material for instance. They must have gone fishing very often  

 

Yeah, the rarity of plesiosaur material versus even pterosaur in the Posidonia Shale is indeed remarkable. I think I've only seen plesiosaur material in the Urweltmuseum Hauff and Museum a single specimen at the Museum am Löwentor. But other than that, plesiosaur material is nowhere to be found...!