Crinoid, coral, blastoid multi-plate
Age: Mississippian/Osagean (approximately 345 million years)
Location: Crawfordsville, Montgomery County, Indiana, USA
Dimensions: 8.5 x 6.5 x 2.55 ”
Weight: 5.9 lbs
Crinoids are a class of echinoderms, commonly known as “sea lilies” and “feather stars”. The stemmed crinoids, or “sea lilies”, first appeared in the fossil record some 530 million years ago but became abundant during the Ordovician Period, flourishing in shallow inland seas, nearly becoming extinct 240 million years ago. These marine animals lived in groups of several thousands, permanently attached to the ocean floor, feeding on microorganisms in the passing sea water. The free-floating stemless crinoids, known as “feather stars”, appeared more recently in the Mesozoic Era. They would swim through the water or crawl on the ocean floor in search of food. Sea lilies still live today, restricted to depths greater than 100 meters. Feather stars are found in shallow tropical reef environments.