Two Edrioasteroid Fossils - Shell Rock Formation, Iowa

This is a pair of Edrioasteroid fossils from the Shell Rock Formation near Nora Springs, Iowa. There are two Edrioasteroids on the limestone, the larger measuring .9" wide and the smaller is .25" wide and are accompanied by various unidentified marine fossil fragments. These echinoderms are from an old collection that had them labelled as Agelacrinites sp. and Timeischytes sp. which are both plausible ID's, but as we are not fossil echinoderm experts, this identification is not definitive.

comes with an acrylic display stand.

Edrioasteroids are an extinct class of echinoderms that lived from the Ediacaran until the Permian, about 300 million years ago. The living animal would have resembled a pentamerously symmetrical disc or cushion.