Two Mississippian Crinoid (Uperocrinus & Macrocrinus) - Iowa

This is a cool plate of Mississippian aged echinoderm fossils from Iowa. There are two crinoid calyxes (Uperocrinus pyriformis and Macrocrinus verneuilianus) on a limestone rock that's full of crinoid and shell fragments.

It comes with an acrylic display stand. Both fossils appear to have been remounted to the rock.

Crinoids, sometimes commonly referred to as sea lilies, are animals, not plants. They are echinoderms related to starfish, sea urchins, and brittle stars. Many crinoid traits are like other members of their phylum; such traits include tube feet, radial symmetry, a water vascular system, and appendages in multiples of five (pentameral). They first appeared in the Ordovician (488 million years ago) and some species are still alive today.

About Crinoids