4) found that some Cuphophyllus and Humidicutis species were unlike ectomycorrhizal and saprotrophic species while

others were unclassified based on their ∂15 N signatures, and all Cuphophyllus and Humidicutis species were unlike ectomycorrhizal and saprotrophic species based on their ∂13 C signatures. Gliophorus laetus, Lichenomphalia, Dictyonema and all Hygrocybe species resembled ectomycorrhizal, but not saprotrophic species based on their ∂15 N, but neither ectomycorrhizal nor saprotrophic species based on their ∂13 C (Fig. 4 vs 3 in Seitzman et al. 2011). Although ectomycorrhizal associations have evolved independently many times in the Basidiomycota (Hibbett et al. 2000) including at least 11 independent origins in the Agaricales (Matheny et al. 2006), they arose only once in the Hygrophoraceae in the monophyletic genus Hygrophorus (Moncalvo et al. 2002; Seitzman selleck inhibitor et al. 2011, our data). These data support the finding of moderate conservation of nutritional strategies in Hygrophoraceae by Seitzman et al. (2011) though the nutritional mode of many genera remains enigmatic. Pigments and other taxonomically informative metabolites The basidiocarp pigments of members of the Hygrophoraceae are among the most diverse and striking in fungi. While the adaptive significance

of many of these pigments is uncertain, their utility in chemotaxonomy has long been recognized. For example, Singer (1958) noted the contrasting effects of 10 % Dichloromethane dehalogenase KOH on the yellow-orange pigments MLN2238 solubility dmso of Hygrocybe flavescens and Humidicutis marginata, Cibula (1976) and Bresinsky and Kronawitter (1986) found pigment chemistry distinguished major groups in Hygrophoraceae, while Bresinsky (2008) described the genus Porpolomopsis based on pigment chemistry. Furthermore, Redhead et al. (2002) used metabolites with other characters in describing Ampulloclitocybe, and Norvell et al. (1994) suggested

a close relationship between Haasiella and Chrysomphalina based on shared carotenoid pigments (Arpin and Fiasson 1971) and pachypodial hymenium construction – a relationship supported by our analyses (Online Resource 3). Though carotenoids are widespread in fungi, notably the Cantharellales (Mui et al. 1998), they are infrequent in Hygrophoraceae where instead the yellow-red pigments are mostly tyrosine-derived betalains (Online Resource 4). Betalain pigments are found elsewhere only among higher plants in the Caryophyllales (except those containing anthocyanins) and a few Amanita spp. (A. muscaria, A. caesaria and A. phalloides, Grotewold 2006). In plants, tyrosinase-mediated hydroxylation of tyrosine to form DOPA by the action of tyrosinase, extradiol ring cleavage catalyzed by a DOPA-dioxygenase leads to the formation of 4,5-seco-DOPA (Online Resource 5). Spontaneous recyclization leads to the formation of betalamic acid (6-membered heterocyclic ring) (Online Resource 5).