Galerina marginata

Galerina marginata is a species of poisonous fungus in the family Hymenogastraceae of the order Agaricales. The fruit bodies of this fungus have brown to yellow-brown caps that fade in color when drying. The gills are brownish and give a rusty spore print. A well-defined membranous ring is typically seen on the stems of young specimens but often disappears with age. In older fruit bodies, the caps are flatter and the gills and stems browner. The species is a classic "little brown mushroom"—a catchall category that includes all small to medium-sized, hard-to-identify brownish mushrooms, and may be easily confused with several edible species. (Wikipedia)