Jump to content

Richmond Cretaceous oddity


Mike from North Queensland

Recommended Posts

Mike from North Queensland

I have been quiet for a while but, sifting through some matrix from the cretaceous of central Queensland Australia I have come across some small fragments that I suspect to be bits of either a spine (spike) or bone.

The bit that has me thrown is there is a distinct grain (striations) appearance on the outer surface that has thrown me. 

This was found in the same batch as the tarsal so could be a clue or a red herring. Photos of top and underside as well as an end view.

Any suggestions appreciated.  Tarsel 4.5 mm - longest unknown bit in two sections 18 mm so not large

 

Mike D'Arcy

Unknown4 15-11-17.jpg

Unknown1 15-11-17.jpg

Unknown2 15-11-17.jpg

Unknown3 15-11-17.jpg

7-11-17 bird 2.jpg

Edited by Mike from North Queensland
dimentions added
Link to post
Share on other sites

Your fragments look like bone and look hollow are they.  Matrix is in the way?.  What is the significance of the phalanx in the last photo?  What is typically found in the area is it terrestrial?

Link to post
Share on other sites
Mike from North Queensland

Troodon the bone would have been hollow and the environment is marine being mostly fish, shark and marine reptile.

The phalanx photo had been added as it will be from a bird as it is the exception for what is typically found in and the bone material does not match the the typical marine material.

What has me confused is the surface texture of the hollow bone material if that is what it is as this was removed from the matrix as the half bits seen. 

My only thought was perhaps an old adult that no longer is growing, so wondering if any one else has seen a similar specimen if the bits are actually bone.

So in essence I am look for consensus for either bone or another option.

 

Mike D'Arcy 

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

I can not help with an ID, but the texture looks much like the texture of some shark or ray spines that I have seen.

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

Looks very much like a fish spine to me also. Besides the preservation, it looks identical to some I have found in New Jersey.

Link to post
Share on other sites

I also think that the first one is a dorsal fin spine. I think it is from a hybodont.

Cretaceous dorsal fin spines are usually from hybodonts, chimaeras or Heterodontus (pics in the same order). Hybodonts have ornamentation on the spine, while chimaeras don't. And Heterodontus spines are enamelous and shiny.

Картинки по запросу hybodont spine

Картинки по запросу chimaera spine

 

Картинки по запросу heterodontus spine

  • I found this Informative 1
Link to post
Share on other sites
Mike from North Queensland

I have found hybondont at the same quarry before and will search and have a close look at the specimens.

 

Mike

Shark fin 1-1.jpg

Shark fin 1-2.jpg

Link to post
Share on other sites
25 minutes ago, Mike from North Queensland said:

I have found hybondont at the same quarry before and will search and have a close look at the specimens.

 

Mike

Shark fin 1-1.jpg

Shark fin 1-2.jpg

 

I think this is a chimaera. I recognized I used a wrong picture for the hybodont spine - they usually have spikes in alternating rows, while chimaeras have two like on this picture. Below is a normal hybodont spine.

The posterior view of the specimens in the previous image clearly shows the staggered, double-row of denticles characteristic of Hybodus dorsal fin spines. ©AMNH

Link to post
Share on other sites

Still looks like bone to me especially because it's smooth surface and roundish.  Could be a bird bone since you found what appears to be a bird phalnax.  Preservation looks similiar.

Link to post
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
  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...