Large Gogia spiralis Eocrinoid Fossil from Utah

Description: Coming from the Cambrian Wheeler Formation deposits of Millard County, Utah this is a fine example of Gogia spiralis, a member of the Class Eocrinoidea. Eocrinoids (“dawn crinoids”), were among the earliest groups of Echinoderms. They had a vase-shaped body (calyx), covered by plates that were symmetrical and had a bifurcated brachiole, a slender arm-like structure for food-gathering that closely resembled those in cystoids. The early Eocrinoids were attached to the bottom by a thick holdfast. Later members had an elongated stalk much like the true crinoids which evolved later. This is a fine large mature example. Once Gogia matured past the 4-armed stage (the species derives its name from the spiraled arms), they added arms in such a way as to have an odd-numbered total.