Cortinarius is the most diverse genus of agaricales – in simple terms, there are a lot of them. Due to the scale and diversity within the genus, as well as the large number of undescribed species, it is very helpful to first learn to identify described “groups” of species with close, phylogenetic relationships, known as sections. Mycologists are still working on the overall phylogenetic tree for the genus, and it is likely to continue to evolve. However, sections provide a foundation for understanding and closer observation.
Phylogenetics is a complex field and groupings may change with new data, or different approaches. many sections are new or still debated. I refer to the following major papers which contribute to our knowledge of sections within North American Cortinarius.
J.Ammirati et al., “Cortinarius Subgenus Leprocybe, Unexpected Diversity and Significant Differences in Species Compositions between Western and Eastern North America” 46 (2021): 24;
Brandrud, Tor Erik, “Cortinarius Sect. Riederi: Taxonomy and Phylogeny of the New Section with European and North American Distribution,” Mycological Progress 17, no. 12 (December 8, 2018): 1350
Sigisfredo Garnica et al., “A Framework for a Phylogenetic Classification in the Genus Cortinarius (Basidiomycota, Agaricales) Derived from Morphological and Molecular Data,” Canadian Journal of Botany 83, no. 11 (November 2005): 1457–77
K. Liimatainen et al., “The Largest Type Study of Agaricales Species to Date: Bringing Identification and Nomenclature of Phlegmacium (Cortinarius) into the DNA Era,” Persoonia : Molecular Phylogeny and Evolution of Fungi 33 (December 2014): 98–140
K. Liimatainen, K. et al., “Mission Impossible Completed: Unlocking the Nomenclature of the Largest and Most Complicated Subgenus of Cortinarius, Telamonia,” Fungal Diversity, September 8, 2020,
K. Soop et al., “A Phylogenetic Approach to a Global Supraspecific Taxonomy of Cortinarius ( Agaricales ) with an Emphasis on the Southern Mycota,” Persoonia – Molecular Phylogeny and Evolution of Fungi 42, no. 1 (July 19, 2019): 261–90