Blastoids are beautiful fossils that look much like small hickory nuts. They most commonly are found in the river cliffs and stream banks of western and southwestern Illinois, especially in Randolph County, and in southern Illinois near the Ohio River.

Is a blastoid alive?

Although blastoids are extinct they still have a lot they can tell us about the 200 million years they were alive. In particular, blastoids have very stable body plates – much like the human skeleton is very stable.

What environment did blastoids live in?

Like crinoids, blastoids were high-level stalked suspension feeders (feeding mainly on planktonic organisms) that inhabited clear-to-silty, moderately agitated ocean waters from shelf to basin.