Cortinarius nymphatus – Facesoffungi number: FoF 02467

Cortinarius nymphatus Kyto ¨v., Niskanen, Liimat. & Bojantchev.

Index Fungorum number: IF551705 Facesoffungi number: FoF02467

Holotype: I. Kyto ¨vuori 95-1549 (H)

Pileus 10–30 mm diam., at first conical to hemisphaerical, later low convex to almost plane with an umbo, surface mat, brown to dark red-brown, paler towards the margin, hygrophanous. Lamellae adnexed, subdistant, moderately broad, moderately thick, at first light brown, becoming medium brown, edges remaining pale for some time, then concolorous. Stipe 40–60 mm long, apex 2–4 mm thick, equal, whitish silky-fibrillose. Universal veil yellow to ochraceous, forming incomplete girdles on the stipe. Basal mycelium white. Context in pileus dark redbrown, in stipe medium yellow-brown. Odour indistinct. Basidia 4-spored, 6.5–8 x 25–30 um, clavate. Basidiospores 6.8–8.2 x 4.3–4.8 um, Q = 1.56–1.76, amygdaloid, finely to moderately, sharply verrucose, slightly to moderately dextrinoid. Lamella trama hyphae moderately encrusted in MLZ. Pileipellis duplex (in MLZ): Epicutis hyphae 4.5–10 um wide, encrusted. Hypoderm distinct, elements up to 30 x 60 um. Trama hyphae 5–13 um wide, somewhat encrusted. ITS sequence (holotype) distinct from the other known members of the clade Fulvescentes/Laeti, and differs from them in the ITS region by more than 7 substitutions and indel positions.

Ecology and distribution: In dry to mesic coniferous forests (Pinus, Picea). Known from Europe, Canada, British Columbia.

Material examined: CANADA, British Columbia, near Squamish, temperate coniferous rainforest (Picea sitchensis, Pseudotsuga menziesii), 19 October 2009, leg. D. Bojantchev DBB21430 (UC). FINLAND, Etela ¨-Ha ¨me, Orivesi, Pa ¨ilahti, mesic to moist Picea abies forest with some Pinus sylvestris and hardwood bushes, 26 September 1995, leg. I. Kyto ¨vuori 95-1549 (holotype, H;isotype, K). Kainuu, Suomussalmi, W of Hossa, dry Pinus sylvestris heath forest on sandy soil, 16 September 2002, leg. I. Kyto ¨vuori, K. Liimatainen & T. Niskanen 02-565 (H).

Notes: Cortinarius nymphatus looks like a small Fulvescentes species, but with a yellow-ochraceous veil. Also based on our phylogenetic analysis it seems to belong to section Laeti s. str. with the yellow-veiled type species, C. laetus, of section Laeti. With the combination of small fruiting bodies and small spores it can be distinguished from the other yellow veiled species of the clade Fulvescentes/Laeti.