This crinoid calyx fossil is not identified. It was found in southern Indiana and is from the Mississippian Period. For reference, the Coca-Cola bottle cap is about 2 cm wide.
Phanocrinus parvaramus crinoid calyx fossil found in southern Indiana. This creature lived in the Mississippian Period. Indiana, USA source of some of the best crinoid fossils in the world!
From the Age of Crinoids or the Mississippian Period, this southern Indiana fossil is thought to be a Culmicrinus elegans (Wachsmuth & Springer, 1897). If the state of Indiana had an official state fossil it would probably be some sort of Mississippian Period crinoid.
