Spring is around the corner when the Earthstars pop out of the ground! These crazy fungi are Gasteromycetes, or "stomach fungi". Their fruiting bodies are a stomach-shaped sac filled with dry spores. They are related to puffballs.
When it rains, the outer two layers of the peridium split and uncurl, forming a "star" with 4 to 12 rays. The inner layer of the peridium remains a closed sac. The rays spread with enough force to push aside leaves, raising the spore-filled sac above surrounding debris. Sometimes the rays even lift the earthstar high enough to break the connection to the parent mycelium. The rays close when they dry, and the sac lowers.