Pholiotina rugosa

Pholiotina rugosa is a common mushroom which is widely distributed and especially common in the Pacific Northwest of the United States. It grows in woodchips, flowerbeds and compost. It has been found in Europe, Asia and North America. It contains the same mycotoxins as the death cap. It is more commonly known as Conocybe filaris as this is the name it is likely to appear under in field guides. However, Conocybe filaris is a junior synonym of Pholiotina rugosa. Pholiotina rugosa has also been placed in the genus Conocybe, but its morphology and a 2013 molecular phylogenetics study place it in the genus Pholiotina. Pholiotina fimicola, which grows on dung and rich soil in North America, is a possible synonym. Pholiotina arrhenii has also been considered a possible synonym, but a molecular phylogenetics study found it to be a distinct species.