Geastrum fimbriatum, Sessile, Earth Star Fungus
These are puff-balls mushrooms of which the outer tunic splits into a star-like pattern. The scientific name “Geastrum” translates as “earth star”, thus the common name, Earth Star Fungus.
Once the sac of spores is exposed dispersal depends on raindrops hitting the sack which causes puffs of spore to shoot out. When I first found this fungus on an island in Panama, not knowing what it was, I lightly touched it and a small cloud was released.