Each amanita starts as an egg-shaped button that can resemble a small puffball.
British Dictionary definitions for amanita
any of various saprotrophic agaricaceous fungi constituting the genus Amanita, having white gills and a broken membranous ring (volva) around the stalk. The genus includes several highly poisonous species, such as death cap, destroying angel, and fly agaric
C19: from Greek amanitai (plural) a variety of fungus