Globulocystites levatus
Cystoid
Ordovician (Blackriverian)
Bromide Formation – Mountain Lake Member
Johnston County, Oklahoma, USA

34mm loose.

Globulocystites is a cystoid that lived during the Ordovician Period.  Its remains have been found in Oklahoma and Kentucky.

Cystoids belong to an extinct order of echinoderms from the Ordovician to Devonian Periods.  Similar to crinoids, they had somewhat rounded, plated, bodies attached to a stalk that was anchored to the sea bottom.

Plates well-defined in this one.