Need of an ID or Understanding, Bumps on a Gastropod Steinkern

[minnbuckeye]

I had the chance to play in the Galena/ Ordovician rocks of SE Minnesota a few days ago. This Fusispira gastropod was found with what appears to be epibionts attached. For the hundreds of gastropods found in this formation, I have never seen an epibiont on them. Then just thinking about the possibility, it occurred to me that this is a steinkern. If they are epibionts, would they not have fallen off when the shell material dissolved away? All thoughts are welcomed! One of my theories is "did water drip onto the fossil, leaving deposits due to the Karst geology of the area", so mini stalagmites. 

 

 

[Rockwood]

I think they started out on the shell, but outlived it. They look like crinoid holdfasts, or perhaps another epibiont. 

[Ludwigia]

Now that is really interesting. I would go along with Rockwood's holdfast assessment. Maybe they could have also attached themselves post mortem using it as hardground.

[rocket]

interesting, holdfast might be a good idea

at the first moment I thougt about a group edrioastroids in steinkern-preservation, but do not think so

The deep rim let me assume perhaps something like inarticulate brachiopods or carinariid-like gastropods

[Rockwood]

The holdfast could have been buried by the time the shell disintegrated, making it more of an anchor.