Via PhysOrg:
...Coronacollina resembles the Cambrian fossil sponge, Choia. The three raised points on the rim are evident, with a central hollow and four spicules extending from the cone rim.... the organism is between 560 million and 550 million years old, which places it in the Ediacaran period, before the explosion of life and diversification of organisms took place on Earth in the Cambrian....
