This fossil appears to be a baby Ectenocrinus crinoid calyx and stem fossil. It is in matrix with group of other creatures found in the Kope Formation (Eden Group) of Carroll County, Kentucky, USA. When it was found part of the stem was covered. It is quite small with the entire fossil about 1 cm in length. How I spotted it is sorta of a mystery, lucky I guess. Fossil dates to the Ordovician Period.
Thanks to Kenny for cleaning the matrix so the entire fossil is visible.