Rare Ordovician Crinoid Starfish Echinoderm Fossil USA

Rare Ordovician Crinoid Starfish Echinoderm Indiana USA

I acquired this slab of the Upper Ordovician Disparid crinoid Iocrinus subcrassus as part of an unprepared lot in the 1990's. This box of material was unprepared until recently when I rediscovered it in my basement. Results of prepping have far exceeded my expectations. Origin of the specimen is the Upper Ordovician Dillsboro Formation in Ripley County, Indiana. Finding a single nice Iocrinus is an rare event, and a slab of fine specimens is very rare indeed.

In addition to the numerous complete examples of the scarce crinoids, I was surprised to find two arms of a Cincinnatian starfish, each of which is about 2.5cm long. The starfish is preserved in the oral aspect, with the ambulacral plates nicely exposed. The specimen appears to be Mesopalaeaster shafferi. See last photo.

I have prepared the specimen with stereo microscope to preserve fine details. Be sure to click on pictures to super-size microscopic detail. Back of slab has been sawed off to reduce shipping weight. Slab measures about 3.5 by 6.5 inches.

Shipping in the US is $4.00 by USPS Priority Mail. Insurance is recommended. Outside USA, shipping is at cost, no handling fee. Thank you for looking.