| Helicocystis Temporal range: | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Stem group: | Echinodermata |
| Family: | †Helicocystitidae |
| Genus: | †Helicocystis |
| Species: | †H. moroccoensis |
| Binomial name | |
| †Helicocystis moroccoensis Smith & Zamora, 2013 | |
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.

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)
Like other early echinoderms, Helicocystis was a marine organism that fed on plankton.