Galerina marginata

Galerina marginata, known colloquially as funeral bell, deadly skullcap, autumn skullcap or deadly galerina, is a species of extremely poisonous mushroom-forming fungus in the family Hymenogastraceae of the order Agaricales. Before 2001, the species G. autumnalis, G. oregonensis, G. unicolor, and G. venenata were thought to be distinct from G. marginata due to differences in habitat and the viscidity of their caps, but phylogenetic analysis showed that they are all the same species. The fruit bodies of the mushroom 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, indistinguishable brownish mushrooms – and thus can easily be......read more on Wikipedia.