Stropharia coronilla
Stropharia coronilla, commonly known as the garland roundhead or garland stropharia, is a species of fungus.
The yellowish cap is up to wide. The gills are grayish and darken with age. The stem is up to 6 cm long and 1 cm thick. It resembles Agrocybe dura, some other members of its genus, plus some in Agaricus and Protostropharia.
Native to Europe and North America, it is considered poisonous.