Identification Help: Fern Glen Crinoid Calyx

[Thomas.Dodson]

Hi all,

I collected this lovely crinoid calyx stuck in a Favosites sp. from the Fern Glen Formation in Imperial, Missouri (Mississippian, Osagean Series). My guess is Platycrinus stellatus (based on Weller, Stuart, Kinderhook faunal studies; V, The fauna of the Fern Glen Formation. Geol. Soc. Am., Bull., vol. 20, 265-:332, (1909)) but I would prefer some more opinions since I'm new to paleozoic strata. On that note I would also welcome learning references on crinoids, especially regarding the Mississippian and Pennsylvanian.

 

Thanks for any help or information.

 

-Tom

[abyssunder]

Probably I'm wrong, but almost looks like a crinoid anchoring sistem. 

[LabRatKing]

I agree this is a lovely crinoid anchor, however it is an interesting coral(?) matrix I’m not qualified to ID

[Thomas.Dodson]

A holdfast does seem more likely as I look at more specimens. I'm still getting used to crinoids and the variation. Thanks for the help.

 

The coral appears to be a Favosites sp. It's nice how tightly it is wrapped around the crinoid. I still have some more work to do blasting the coralites with my micro abrader but it looks nice.

[Packy]

I agree its a holdfast but its awesome. That looks like a material that could be cleaned in acid , you may want to try  a   not worth saving specimen, it could save time` and preserve more detail. Just be real carefull.   The coral in my member photo was complexly covered in matrix. Packy

[Thomas.Dodson]

Hey Packy,

 

The specimen was similarly covered in matrix and the more worn outer layer was initially prepped in acid. It preps in acid pretty well (I tested some brachiopods from the site initially) but eventually the coral couldn't stand up to the acid any longer so I switched to the dental sandblaster.