Could these possibly be fish vertebrae?

[matgerke]

I found four of these fossils in a Devonian site (Mahatango, I think).  To my eye they look like vertebrae, but that seems so extremely unlikely at a site that is mostly given over to crinoids, brachiopods and trilobites.  I have never found any fish there.

 

What are they?

 

Thanks in advance for any help.

 

Matt

[connorp]

Not vertebrae. Looks like an internal mold of something, maybe a cephalopod?

[tzdoss]

It doesn’t look like a cephalopod mold to me. 

[Tetradium]

59 minutes ago, connorp said:

Not vertebrae. Looks like an internal mold of something, maybe a cephalopod?

There's big burrow fossils as well too. I had found big ones in Lime Creek Formation in Rockford Iowa which is pretty close to Mahatango I thinks. 

1 hour ago, connorp said:

Not vertebrae. Looks like an internal mold of something, maybe a cephalopod?

Here's a picture. Sorry for not including scales. 

[Tetradium]

1 hour ago, connorp said:

Not vertebrae. Looks like an internal mold of something, maybe a cephalopod?

After all I hope someday we find the Burgess shale version of Ordovician/Silurian/Devonian marine life forms but as the years go by the odds get smaller as more areas of the Earth surface get explored by geographers mainly in politically unstable regions or under ice sheets. After all we have the giant Bobbitt worm, identified by jaw segments but there are huge burrows made by giant unknown soft bodies invertebrates, either worms or sea cucumbers that no one knows what makes them. 

[tzdoss]

@Tetradium, nice burrows you have! @matgerke's photos look like segments and unlike your burrow fossils, they are very smooth around the sides and have a particular symmetrical indentation in the middle, similar to what we see in vertebrae, except no apparent opening in the center. Very curious.

[matgerke]

@Tetradium @tzdoss @connorp

I am inclined to agree with TZ doss that these don't really resemble steinkerns or burrows. They are far too regular, all the same size, and have the characteristic tapering cylindrical curve of a vertebra. I'm willing to accept that they are probably not vertebra, but I just can't wrap my head around these being burrows or casts. The regularity in size, shape, and texture makes burrows pretty unlikely.

Any other thoughts on what these might be?

[JohnJ]

@matgerke Posting some additional, sharp photos of the circular surface would be useful.  Even really old bone has characteristic texture.