The weirdest Fossil I have found so far (Missouri)

[Samurai]

Hello! this is one of my weirdest things I have found at this location, I believe it might be a fragment from a fin spine? A piece from an Echinoid? Something else?

I would love to know what it is and what species this came from!

 

Some information on the area:
Location: Missouri

Time period: Pennsylvanian

Formation: Most likely from a member of the Iola Limestone 

 

What makes this one of the most bizarre fossils I have found is the circular pattern on the fossil itself, as I have not seen anything like this in the area before. 

 

 

 

 backside

 

 

 

 

Pictures in their natural file size:

https://imgur.com/a/qUWY0gB

 

 

[Jackson g]

Hmm has me stumped. A few photos make me want to take a guess, but then other photos with different viewpoints throw that guess out. Do you find any flora there, and or can you also tell if the "bumpy" side is the exterior or interrior?

[connorp]

I would definitely think fin spine fragment. Neat find.

[Samurai]

2 minutes ago, Jackson g said:

Hmm has me stumped. A few photos make me want to take a guess, but then other photos with different viewpoints throw that guess out. Do you find any flora there?

I have found fossilized wood in the area, although none this small or white, here are a few photos of the most common pieces I find

 

[Samurai]

18 minutes ago, connorp said:

I would definitely think fin spine fragment. Neat find.

Thank you! I thought it might be as well, would you by chance have a guess to what it belongs too? 

 

if this information could help

I have found teeth from several chondrichthyans in the area including Petalodus, Deltodus, Campodus, and a few other species

[Fossildude19]

@Missourian  @jdp

 

It's cool, whatever it is.    

[connorp]

18 minutes ago, Samurai said:

Thank you! I thought it might be as well, would you by chance have a guess to what it belongs too?

I am not familiar with fin spine classifications. A good starting point might be Ctenacanthus.

http://oceansofkansas.com/Ctenacanthus/ctena06.jpg

[daves64]

Could be part of a drum fish mouth plate minus teeth. Or not.. Just tossing a "could be" out there. 

[jdp]

1 hour ago, connorp said:

I am not familiar with fin spine classifications. A good starting point might be Ctenacanthus.

http://oceansofkansas.com/Ctenacanthus/ctena06.jpg

yeah thinking this is what this is

[LabRatKing]

I agree. Have seen similar structures in extant species. Is a thread on here in the Africa heading that is similar. Cool find!

[SWMOnaturalist]

I haven't seen one of these before, that's a neat find.

[sander]

from the side it reminds me very much of a tree fern cross section. the small round things look a bit similar to Sigillaria bark. I think it is wood. never saw that structure in a shark spine.

[Brandy Cole]

Is there fossilized palmwood where you are?  Especially the cross section and backside pictures you posted reminded me of some of the palmwood I've seen.

[Mahnmut]

Lego?

[ParkerPaleo]

Are there crinoids in the Iola?  Could it be an anal sac?

[snails]

I believe Connorp and associates are correct with a Ctenacanthus attributions. See the 2016 paper on Ctenacanthus spines and denticles at

CTENACANTHUS AND OTHER CHONDRICHTHYAN SPINES (researchgate.net)