Marine Cretacious Something

[Mike from North Queensland]

Went out fossicking last week and picked up a bone fragment that I cant identify

this was found in my usual haunt central Queensland Australia in cretaceous (Albian ) marine deposits.

Looked but could not find any more of this bone or other bone in the immediate area to give a clue. road base by now unfortunately.

Appreciate any help

Mike

[Mike from North Queensland]

Just look at my phots and realised there was no photo of the end thats broken

Mike

[Maniraptoran]

looks like a crocodile scute

[Indy]

Not familiar enough with fossils of this time period

to venture and ID...However, I do enjoy editing pictures

to help these old eyes see features of interest

picture 1

picture 3

[Opisthotriton]

Thanks for the enhanced photos!

It's the end of a larger bone, most likely a phalanx (toe bone), based on the texture of the side view. Less likely, it could be the end of a larger limb bone, or a vertebra.

Based on size, shape, and texture, it's either dinosaur or marine reptile. It looks very dinosaurian to me, but I'm not too familiar with marine reptile limbs. Plenty of dino bones end up in marine sediments, though (bloat & float).

So, if I had to pick something specific, I'd say it's an ornithiscian dinosaur phalanx. Or something similar.

[Auspex]

So, if I had to pick something specific, I'd say it's an ornithiscian dinosaur phalanx. Or something similar.

An ungual phalanx ("hoof core") perhaps?

[Mike from North Queensland]

I have taken a couple of more photos of the larger intact side of the fossil as the original photos did not show justice to the uneven surface.

From the texture I think this surface would be used to attach sinews for muscle.

Unsure about the hoof idea but will look up the phalanx idea and the ornithiscian dinosaur phalanx.

The crocodile scute idea looks good from the top but I would expect the other side to be flat not a broken surface where the bone will continue.

As one of the best preserved ankylosaur mummies (minmi) was found about 100 kilometers away dinosaur could be a canditate.

I did pick up a claw within 20 metres however of this find but it was only 5mm long so bird was my best guess there.

Mike

Edited September 27, 2011 by Mike from North Queensland

[Opisthotriton]

An ungual phalanx ("hoof core") perhaps?

Yes, of all the phalanges, I agree that a ungual "hoof" is most likely.

I suppose it could be ankylosaur, although I'm not too familiar with their feet.

http://blogs.smithsonianmag.com/dinosaur/2010/11/a-new-view-of-ankylosaur-feet/

http://goldbergcoins.auctionserver.net/view-auctions/catalog/id/2/lot/2897/

[Maniraptoran]

ankylosaur hoof core? im not so sure.

1. i dont see anything that looks like a toe joint on that thing.

2. the upper surface resembles dermal bone

3. are ankylosaurs commonly found in marine deposits? i have a hard time imagining those things floating

[Opisthotriton]

ankylosaur hoof core? im not so sure.

"1. i dont see anything that looks like a toe joint on that thing."

Well, the articulation surface is pretty rugose, more so than you'd normally see on a phalanx, but if it was a young animal the cartilage cap would be thicker than normal, attaching to the rugose bone surface.

"2. the upper surface resembles dermal bone "

No, it really doesn't. It resembles an epiphysis/condyle. Normally a condyle that rugose would be found on a larger bone such as a femur, but can also be found on certain metatarsals. So maybe this is a metatarsal. And the side view is clearly cortical endochrondral bone, not the dense structure of dermal bone.

"3. are ankylosaurs commonly found in marine deposits? i have a hard time imagining those things floating"

It does seem counterintuitive, but ankylosaurs and other armored dinosaurs such as Scutellosaurus are surprisingly common in marine and nearshore deposits. This is interpreted as a combination of a preference for a lowland habitat with a propensity for "bloat & float" carcass transport.

http://books.google.com/books?id=h4WRTHfTzXsC&pg=PA342&lpg=PA342&dq=scutellosaurus+marine&source=bl&ots=j80UUEBtDd&sig=3JLhrCP__X833X2Pfl7GdyzqpJM&hl=en&ei=JWaDTuzGMYrZiALLv5SFDQ&sa=X&oi=book_result&ct=result&resnum=6&sqi=2&ved=0CEYQ6AEwBQ#v=onepage&q=scutellosaurus%20marine&f=false

http://www.oceansofkansas.com/Dinosaur.html

http://en.wikipedia.org/wiki/Pawpawsaurus

I don't want to sound like I'm saying this is certainly an ankylosaur; it's just a valid possibility, equally with any other ornithischian dinosaur. I'd still like to compare it to some marine reptile limb elements.

[Maniraptoran]

ok then,

i guess you can strike down all of my last statements and replace all bullet points with the word "derp".

thank you

[piranha]

Great information Opisthotriton. Thanks for taking the time to post!

[jnoun11]

I have taken a couple of more photos of the larger intact side of the fossil as the original photos did not show justice to the uneven surface.

From the texture I think this surface would be used to attach sinews for muscle.

Unsure about the hoof idea but will look up the phalanx idea and the ornithiscian dinosaur phalanx.

The crocodile scute idea looks good from the top but I would expect the other side to be flat not a broken surface where the bone will continue.

As one of the best preserved ankylosaur mummies (minmi) was found about 100 kilometers away dinosaur could be a canditate.

I did pick up a claw within 20 metres however of this find but it was only 5mm long so bird was my best guess there.

Mike

hi mike

definitively a femur of plesiosaur on is picture and the first pictures of this topics are some toe bones of the same animal.

friendly

jnoun

[Mike from North Queensland]

Jnoun11 - I think you may be right as there were some Pliosaur flangies found near where I got this piece of bone.

but initally I didn't think the conecting end of the bone would be so uneven. This is the first piece of Pliosaur bone for me.

I have collected a few teeth the largest is my avitar from a Kronosarus.

Thanks all that looked and contributed in the thread.

Mike