Cortinarius laccariphyllus 2020

Cortinarius laccariphyllus Y. Li & M.L. Xie, sp. nov. 2020

MycoBank No: 830780

Holotype: China. Jilin Province: Antu County, Liangjiang Town, Dongfanghong Village, broadleaf forest (Quercus mongolica dominated forest with some Juglans and Acer), 42°42'51"N, 128°01'10"E, alt. 640 m, 5 August 2017, M.L. Xie, HMJAU44449, GenBank No. (ITS) MK552380.

Morphological description

Pileus 2.2–6.6 cm in diam., conical when young, then convex, strongly hygrophanous, reddish-brown (9E6–8), dark brown at the centre (8F6–8), margin to half-way translucently striate, rarely fibrillose, margin thin and wavy. Lamellae subadnate to emarginated, distant, Laccaria-like (Laccaria laccata (Scop.) Cooke) when young, reddish-brown (9E6–8) to rusty brown (6E8), edge slightly serrate. Stipe 4.2–6.6 cm long, 0.4–0.8 cm thick at apex, 0.2–0.5 cm thick at base, cylindrical to tapering towards base, dark brown (7F6) to black brown (7F3), surface with white fibrillose when young, these disappearing with age (excluding the base of stipe). Universal veil white, extremely sparse, soon disappearing. Context dark brown (7F6–8), strongly hygrophanous (pileus and stipe). Odour indistinct. Exsiccata brown (5F8) to black brown (7F5). UV fluorescence yellow on stipe, pileus and lamellar edge, strong at stipe base.

Basidiospores 7.7–9.7 × 4.5–5.8 μm, Q = 1.43–1.84, `X = 8.0–8.5 × 4.8–5.2 μm, `Q = 1.66–1.70 (60 spores, 2 specimens), ellipsoid to amygdaloid, moderately and sharply verrucose, moderately dextrinoid. Basidia 4-spored, clavate, 23–39 × 7–9 μm, thin-walled, hyaline to olivaceous brown in 5% KOH. Lamellar edge fertile, with cylindrical-clavate sterile cells, 14–41 × 7–17 μm, thin-walled, hyaline in 5% KOH. Lamellar trama hyphae regular, pale olivaceous to olivaceous brown in 5% KOH, finely and densely encrusted. Pileipellis: epicutis hyphae cylindrical, 4–9.5 μm wide, dark olivaceous brown in 5% KOH, encrusted; hypocutis well developed, hyphae 11.5–53 μm wide, sub-cellular to cylindrical, slightly olivaceous in 5% KOH, finely encrusted. Pileus trama hyphae thin-walled, hyaline to slightly olivaceous in 5% KOH, smooth to finely encrusted. Clamp connections present.

Habitat: In broadleaf forest (Quercus mongolica dominated forest). 

Distribution: Jilin Province, China.

GenBank Accession: No MK552380, MK552381

Notes: Cortinarius laccariphyllus has strongly hygrophanous basidiomata, Laccaria-like (when young), with distantly-spaced lamellae and an extremely sparse, white veil. Morphologically, C. nolaneiformis (Velen.) Dima, Niskanen & Liimat. is similar to C. laccariphyllus due to the strongly hygrophanous pileus, similar colouration and similar size of spores. Cortinarius uraceomajalis Dima, Liimat., Niskanen & Bojantchev is also similar to C. laccariphyllus because of the black brown stipe and the striate pileus. However, both C. nolaneiformis and C. uraceomajalis have a yellowish veil and medium-spaced lamellae and lamellae not Laccaria-like. Furthermore, C. nolaneiformis is associated with broadleaf trees and also occurs in coniferous forest; C. uraceomajalis has a somewhat lighter brown pileus as well as generally smaller (av. 7.8–8.1 × 4.6–4.7 μm) and narrower (Qav. > 1.7) spores (Dima et al. 2014). In the phylogenetic analyses, C. laccariphyllus was well separated from other species in section Colymbadini.

Reference: Xie M-L, Wei T-Z, Fu Y-P et al. (2020) Three new species of Cortinarius subgenus Telamonia (Cortinariaceae, Agaricales) from China.

Basidiocarps of three newly-described species. a, b Cortinarius laccariphyllus (a, b HMJAU44449, holotype);

Basidiospores of three newly-described species. a Cortinarius laccariphyllus (HMJAU44449, holotype);

Margin cells of three newly-described species. a Cortinarius laccariphyllus (HMJAU44449, holotype);