Xeromphalina enigmatica K. W. Hughes

4. Xeromphalina enigmatica K.W. Hughes & R.H. Petersen, in Aldrovandi, Johnson, O’Meara, Petersen & Hughes, Mycologia 107(6): 1280 (2015) (Figs. 4, 8) Diagnostic characters. Pileus 7-15 mm in diameter, convex to plano-convex with a depressed center; upper surface orange-brown to yellow-brown, with stria margin. Lamellae decurrent, distant, bright yellow to orange, with intervenose. Stipe 10-40 × 0.5-2.0 mm, cylindrical, equal to tapering downward, curved, yellowish above, reddish-brown to dark brown with hairs, smooth. Basidiospores 5.2-8.2 × 3.1-4.2 μm, ellipsoid, smooth, thin-walled, hyaline. Basidia 19-32 × 3.9-7.5 μm, clavate, hyaline, smooth, with 4-sterigmata. Pleurocystidia 32-62 × 5.0- 14 μm, clavate to cylindrical, hyaline, thin-walled. Habitat. Gregarious on moss in mixed forests. Material examined. KOREA, Taebaeksan National Park, Taebaek-si, Gangwon-do, 37°5 ʹ 32.08 ʺ N 128°55 ʹ 57.76 ʺ E, 4 vii 2023, NK Kim, NIBRFG0000515416. Remarks. In a previous phylogenetic analysis based on ITS, 28S, and RPB2 sequences, this species comprised several clades (Aldrovandi et al., 2015). The phylogeny in this study showed that the Korean collection is clustered with a well-supported monophyletic clade (Fig. 8). Therefore, the Korean collection was identified as X. enigmatica.