Helicocystis is an extinct genus of early echinoderm known from the Jbel Wawrmast Formation of Morocco, dating to the Cambrian Stage 5 (approximately 507 million years ago). It represents a significant transitional fossil in the evolutionary history of echinoderms, as it possesses a pentaradial (five-fold) body plan while maintaining characteristics of more primitive, spiral-shaped ancestors.
Description The Helicocystis can be described as a stalked, spiralling pentaradial echinoderm known from the Cambrian Jbel Wawrmast Formation. The approximate length is between 5 and 20 millimeters (0.2 to 0.8 inches)
Ecology Like other early echinoderms, Helicocystis was a marine organism that fed on plankton. References