.8" Crinoid (Rhodocrinites) Fossil on Rock - Gilmore City, Iowa
This is a 1.8" wide fossil crinoid plate containing a crinoid of the species Rhodocrinites douglassi. The rock has been meticulously prepped away using air abrasives, to reveal the beautiful structure of this crinoid. It was collected from the Gilmore City Formation in Gilmore City, Iowa.
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.