Scleroderma citrinum
The most common of the earthball fungi, often confused with truffles or puffballs. Its thick, warty, yellowish skin encloses dark purple-black spore mass. It is poisonous and should not be confused with edible puffballs. Common under birch and oak.
Conservation Status: LC
Least Concern — assessed by the IUCN Red List of Threatened Species.