Detailed Prehistoric Scyphocrinites Crinoid Fossil from Morocco. 480 Million Years Old. Large size 11" H, perfect for display. Crinoid Fossils make up the class Crinoidea of the Echinoderms (Phylum Echinodermata). Crinoids were some of the earliest animals to live in the ocean dating as far back as the Cambrian period about 488 million years ago. At that time the supercontinent Gondwana was in the southern hemisphere and contained most of the land. The Crinoid had a stem with a crown consisting of a central body with arms usually branched and feathery giving it a lily-like appearance. Crinoids ate bits of small organisms and obtained nutrients from plankton, detritus, and larva.