Fourteen coprophilous species of Psathyrella identified in the Nordic countries using morphology and nuclear rDNA sequence data.

Psathyrella species growing on dung or occasionally on dung in the Nordic countries were studied using morphological characters and nu-rDNA sequence data and type collections were examined when available. Fourteen species capable of growing on dung were identified. Descriptions are given of all dung-inhabiting species and to a lesser extent of the species occasionally growing on dung. Three new species are described: Psathyrella fimiseda, P. merdicola, and P. scatophila. P. stercoraria is described as a new species in order to validate the name. A key to the coprophilous species in Europe including the species described by Peck & Smith from North America is provided. The phylogenetic analyses recovered four major supported clades within Psathyrellaceae corresponding to Parasola, Coprinopsis, Lacrymaria/Spadiceae pro parte, and Psathyrella. The status of Coprinellus was ambiguous. The current morphology-based infrageneric classification of Psathyrella was not supported by the phylogenetic analyses and a coprophilous habit has apparently evolved on multiple occasions. Three new combinations are proposed: Parasola conopilus, Coprinopsis marcescibilis, and Coprinopsis pannucioides.