Agaricocrinus Crawforsville Crinoid With Rare Starfish!

This is a really cool specimen from the famous Crawforsville, Indiana crinoid beds. It's a beautifully preserved and very 3D Agaricocrinus americanus crinoid overlaying a starfish (Onychaster flexilis). The starfish fossils from this beds are very rare. The specimen has been meticulously cleaned under microscope using air abrasives.

Crinoids from the Ramp Creek Limestone were likely buried in sediment from nearby deltas during storms. The resulting siltstone deposits are soft enough that fossils can be extracted in exquisite, three-dimensional relief.

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