Cortinarius steglichii: a taxonomical and chemical novelty from Chile.

The new species Cortinarius steglichii is described from Chilean Nothofagus forest based on morphological and microscopical attributes, molecular phylogeny, and chemical analysis of secondary metabolites. C. steglichii is characterized by abundant, long, ramified cystidia on the lamellar edges and stipe apex, further by a deep violet color reaction after treatment with KOH. As responsible secondary metabolite for the cytoplasmatic color reaction of cystidia and some hyphae, the new diterpenoid steglichon (1) could be recognized, showing also remarkable antibacterial and anticancer activity. Phylogenetic analyses (ITS, LSU, RPB1) confirm the close relationship to species of the Cortinarius dulciolens group. [ABSTRACT FROM AUTHOR]