Blue Spring Cave Fossil

[Dinictis]

This is not one I am familiar with. It is found in the "Root Cellar" passage of Blue Spring Cave. Blue Spring Cave is the longest cave in Tennessee and is formed within the Monteagle limestone in White County, TN. The cave has many spectacular fossils exposed in the very walls and ceiling.

Sorry for lack of size reference. This little thing was under an inch long.

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What do you think it is?

Thanks for looking!

[izak_]

It looks like a brachiopod shell.

[Dinictis]

Thank you! It seemed odd because the texture of the shell seemed different from most brachipods, but it does look like a shell of some sort.

[izak_]

We have found shells similar to that, aged miocene. And no problem I can't say what species, though.

[Dinictis]

Thank you! This being in Mississippian/early Carboniferous strata makes it pretty old. Brachiopods have been around a while!

[Guguita2104]

I have some doubts about brach...The "shell" is quite odd.

[Dinictis]

I have some doubts about brach...The "shell" is quite odd.

Do you have any idea what it could be? The "shell" shape/texture is why I didn't think "brachiopod" right away. Unless it is pretty weathered? I'm very familiar with the usual brachiopods we have around here and it isn't one of the usual ones. Elsewhere in the cave, Mississippian aged shark teeth have been found of a similar color, but this looks nothing like any shark teeth I am familiar with. (I should add that I am not familiar *at all* with Mississippian shark teeth.)

Edited March 20, 2016 by Dinictis

[Guguita2104]

After research I'll say shark, but I'm not an expert (in anything )

[Dinictis]

Thank you! Very interesting. I will keep my camera out for other fossils on future trips. The cave is full of them!

[PA Fossil Finder]

I think this fossil is a brachiopod. It may be some sort of inarticulate brachiopod - inarticulate brachiopods have a calcium phosphate shell that often looks blue or black and can be easily mistaken for a Paleozoic shark tooth. Also, in the last picture you can see the slightly open hinge line and the pedicle opening.

[Dinictis]

I think this fossil is a brachiopod. It may be some sort of inarticulate brachiopod - inarticulate brachiopods have a calcium phosphate shell that often looks blue or black and can be easily mistaken for a Paleozoic shark tooth. Also, in the last picture you can see the slightly open hinge line and the pedicle opening.

blue springs brachiopod.jpg

Thank you so much for taking the time to look over the fossil and make that diagram! Well done! I am kind of a fossil newbie and had never heard of inarticulate brachiopods. I just looked up inarticulate brachiopods. Having seen it in person, I can tell you that that is exactly what it looked like. It strongly resembles the ones labeled Orbiculoidea. Thank you again.