Systematic study of Panaeolus (Agaricales, Galeropsidaceae) sensu lato and psilocybin-producing traits of species from China

Panaeolus sensu lato is a group of hallucinogenic mushrooms commonly found on dung, in pasture areas, grasslands, and forests. Previous studies indicated that the Panaeolus s.l. clade (panaeo-clade) could be ranked as a family ( Galeropsidaceae ), pending further evidence. In this study, based on phylogenomic, multigene phylogenetic, molecular clock, and morphological analyses, the panaeo-clade is demonstrated to be a distinct family, separate from Bolbitiaceae . The taxonomic system of Galeropsidaceae is revised. The genera accepted in Galeropsidaceae are Panaeolus and Staktophyllus , whereas Crucispora and Panaeolopsis are synonymized under Panaeolus . Three subgenera are accepted in Panaeolus : subg. Bresadolomyces, subg. Panaeolina, and subg. Panaeolus. Subgenus Bresadolomyces is roughly equivalent to the traditional circumscription of subg. Copelandia but is extended to include species formerly placed in Crucispora . Subgenus Panaeolina comprises most species from China and Anellaria-like species. Subgenus Panaeolus mainly comprises the P. papilionaceus species complex and a western Asian clade represented by P. punjabensis . In this study, one new subgenus and eight new species are proposed. Species from China are documented with descriptions, photographs, and illustrations. Additionally, the psilocybin-producing traits of 14 species were tested using high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS). Two species are confirmed to possess psilocybin-producing traits, namely the known species P. cinctulus and the new species P. subfoenisecii proposed in this study. The evolution of the coprophilous lifestyle and psilocybin-producing traits in Panaeolus is also discussed based on phylogenetic relationships and divergence times.