Aurei clade comprising H. hypothejus (as H. speciosus and H. lucorum) and H. flavodiscus. Support is high for a subsect Aurei clade comprising H. flavodiscus and H. hypothejus (as H. lucorum) in our Supermatrix analysis (100 % MLBS) and is also high (76 % MLBS) in our ITS analysis for the clade comprising H. gliocyclus and H. hypothejus. Larsson’s (2010; unpublished data) presentation shows 100 % MPBS support for subsect. Aurei including H. hypothejus, H. hypothejus var. aureus, H. gliocyclus, H. flavodiscus and H. speciosus.

Species included Type species: Hygrophorus hypothejus. Taxa included based on both molecular and morphological APR-246 ic50 data are H. hypothejus var. aureus (≡ H. aureus), H. gliocyclus Fr., H. flavodiscus Frost, H. lucorum Kalchbr. and H. speciosus Peck. H. whiteii Hesler & A.H. Sm. is included based on

morphology . Comments The well supported clade representing subsect. Aurei is concordant CP673451 with the morphology-based subsect. Aurei delineated by Bon (1990) and Candusso (1997), partly concordant with series Aurei in Hesler and Smith (1963), but not concordant with the classifications by Singer (1986), Kovalenko (1989, 1999, 2012) or Arnolds (1990). Hygrophorus , subsect. Discolores E. Larss., subsect. nov. MycoBank MB804115. Type species Hygrophorus karstenii Sacc. & Cub., Syll. Fung. (Abellini) 5: 401 (1887), = Hygrophorus bicolor P. Karst. (1878), nom. illeg. homonym of H. bicolor Berk. & Broome (1871). Etymology: dis – different, colores – color, for the contrasting color of the lamellae and pileus. Pileus surface subviscid when moist, soon dry, dull, yellowish beige, sometimes with a red tint; lamellae decurrent, cream or egg yolk-yellow, more or less darkening upon drying; stipe dry, dull, pale yellowish beige or with age more ochre brown; odor none or like marzipan. Phylogenetic support Hygrophorus secretanii and H. monticola A.H. Sm. & Hesler are included in our ITS analysis (Online Resource 9), while H. karstenii and H. secretanii are included in the 4-gene analysis presented by this website Larsson (2010, unpublished data). Although there is 100 % MLBS support for the subsect. Discolores clade check details in our ITS analysis, H. monticola is a synonym

of H. secretanii. In the multigene phylogeny of Larsson (not shown), subsect. Discolores appears as a paraphyletic grade that is basal to subsect. Aurei. There is no significant support for the branches in this grade, except for the species (100 % MPBS). Species included Type species: Hygrophorus karstenii. The inclusion of H. secretanii Henn. =H. monticola is supported by both morphological and molecular data. Comments Hygrophorus karstenii and H. secretanii (syn. H. monticola Hesler & A. H. Sm.) are both northern boreal species associated with Picea and Pinus. The species were not treated by Arnolds (1990), but partly treated by Hesler and Smith (1963) and Singer (1986). The name H. melizeus Fr. is used for H. karstenii in both Candusso (1997) and Kovalenko (2012).