Among several groups of rare echinoderms known from Ohio are edrioasteroids, which are small, circular animals with starfish-like arms on the dorsal surface. They are usually found attached to the shell of a brachiopod or other shelled invertebrate.
- Ausich, W. I., 1996. "Phylum Echinodermata," in Fossils of Ohio, edited by R. M. Feldmann and Merrianne Hackathorn. Ohio Division of Geological Survey Bulletin 70, p. 242-261.