Large, 2.2" Eucalyptocrinus Crinoid Crown With Arms - Indiana

This is a large and very 3D crown of the crinoid Eucalyptocrinus crassus from Waldron Shale of Indiana. While crowns of these crinoids are fairly common you rarely see them with the arms still attached like this specimen. It has been cleaned under microscope using air abrasives and mounted on a piece of shale from the same location for display.

Crinoids are commonly known as sea lilies, though they are animals, not plants. They are echinoderms related to starfish, sea urchins, and brittle stars. They attached themselves to the sea floor and had feathery, tentacle-like appendages which they used to capture particles of food. First appearing in the Ordovician period, 488 million years ago, they still survive to this day in deep water.