Cortinarius neotorvus Y. Li, M.L. Xie & T.Z. Wei, 2020

Xie, Meng-Le, Wei, Tie-Zheng, Fu, Yong-Ping, Li, Dan, Qi, Liang-Liang, Xing, Peng-Jie, Cheng, Guo-Hui, Ji, Rui-Qing & Li, Yu, 2020, Three new species of Cortinarius subgenus Telamonia (Cortinariaceae, Agaricales) from China, MycoKeys 69, pp. 91-109 : 91

Cortinarius neotorvus Y. Li, M.L. Xie & T.Z. Wei sp. nov. Figures 2c, d , 3b , 4b

Diagnosis.

Pileus 2-4.4 cm in diam., weakly hygrophanous, orange grey. Lamellae greyish-red when young. Stipe cylindrical to somewhat tapering towards base. Universal veil greyish-yellow. Context white, sometimes with violet tinge at the stipe apex. Basidiospores 8.5-10.2 × 5.8-6.9 μm. Lamellar edge sterile. The ITS sequence of the holotype differs from the sequences of other species in section Telamonia by at least six substitutions and five indels.

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, HMJAU44441, GenBank No. (ITS) MK552384.

Etymology.

The name refers to Cortinarius torvus .

Description.

Pileus 2-4.4 cm in diam., hemispherical when young, then convex to almost plane with a low, broad umbo, weakly hygrophanous, orange grey (5B2), paler at the margin, surface with greyish-white fibrillose. Lamellae emarginate, medium-spaced, yellowish-grey (4B2), greyish-red (9B4-6) when young, sometimes with violet tinge when young, margin paler, slightly serrate. Stipe 4.1-10.5 cm long, 0.5-0.7 cm thick at apex, 0.3-0.5 cm thick at base, cylindrical to somewhat tapering towards base, orange grey (5B2) when moist, sometimes with violet tinge at the apex when young, surface with richly whitish fibrillose. Universal veil greyish-yellow (4B3), copious, usually forming a girdle on the upper stipe, cortina white. Context white (A1), marbled watery when moist, sometimes with violet tinge at the apex of the stipe. Odour indistinct. Exsiccata brown (6E5) to dark brown (6F6).

Basidiospores 8.5-10.2 × 5.8-6.9 μm, Q = 1.31-1.67, 'X = 9.0-9.9 × 6.1-6.5 μm, 'Q = 1.45-1.61 (130 spores, 6 collections), ellipsoid, moderately verrucose, moderately dextrinoid. Basidia 4-spored, cylindrical to clavate, 27-53 × 7-12 μm, thin-walled, hyaline to olivaceous brown in 5% KOH. Lamellar edge sterile, sterile cells cylindrical-clavate, 11-26 × 3-9 μm, thin-walled, hyaline in 5% KOH. Lamellar trama hyphae regular, pale olivaceous in 5% KOH, smooth. Universal veil hyphae thin-walled, hyaline to pale olivaceous yellow in 5% KOH. Pileipellis: epicutis hyphae cylindrical, 2-6 μm wide, olivaceous brown in 5% KOH, smooth; hypocutis well developed, hyphae 15-38 μm wide, sub-cellular, thin-walled, hyaline in 5% KOH, smooth. Pileus trama hyphae thin-walled, hyaline to slightly olivaceous in 5% KOH, smooth. Clamp connections present.

ITS sequence.

The ITS sequences of C. neotorvus are 513-515 bp long (5 collections, Table 1 ). All four sequences (MK552384 holotype, MK552385, MK552386 and MK552382) are identical and only MK552383 has 2 bp indels. The ITS sequence of C. neotorvus (MK552384, holotype) differs from the sequences of other species in section Telamonia by at least six substitutions and five indels.

Ecology and distribution.

In broadleaf forest ( Quercus mongolica dominated forest). Solitary or gregarious. Known from Jilin and Heilongjiang Province, China.

Additional specimens examined.

China. Heilongjiang Province: Heihe City, Wudalianchi Scenic Area, broadleaf forest ( Quercus mongolica ), 48°39'15"N, 126°28'18"E, alt. 290 m, 16 August 2017, M.L. Xie, HMJAU44442, GenBank No. (ITS) MK552385; 12 August 2018, P.J. Xing, HMJAU44440; Heihe City, Shengshan National Nature Reserve, broadleaf forest ( Quercus mongolica dominated forest with some Tilia and Alnus ), 49°30'N, 126°43'E, alt. 300 m, 11 September 2017, G.H. Cheng, HMJAU44443, GenBank No. (ITS) MK552386. Jilin Province: Yanji City, Sandaowan Town, broadleaf forest ( Quercus mongolica ), 43°16'10"N, 129°07'19"E, alt. 580 m, 8 September 2018, M.L. Xie, HMJAU44437, GenBank No. (ITS) MK552382, HMJAU44438, GenBank No. (ITS) MK552383, HMJAU44439.

Comments.

Cortinarius neotorvus is easily confused with C. torvus due to highly similar morphology. Morphologically, the lamellae of C. torvus are adnate to subdecurrent and distant ( Bidaud et al. 1999; Breitenbach and Kränzlin 2000; Soop 2014) and the pileus colour of C. torvus is usually darker and with a violet tinge, as well as the stipe usually being bulbous at the base ( Consiglio et al. 2003). In molecular data, the ITS sequence of C. neotorvus (MK552384, holotype) differ from the sequences of C. torvus (AY669668, JX407337) by six substitutions and five indels. In the phylogenetic analyses, the five specimens of C. neotorvus were placed in separate monophyletic lineages (BPP = 0.96, MLBS = 90%) and formed a sister relationship with C. torvus .

Figures

Figure 2. Basidiocarps of three newly-described species. a, b Cortinarius laccariphyllus (a, b HMJAU 44449, holotype); c, d Cortinarius neotorvus (c HMJAU 44441, holotype; d HMJAU 44439); e, f Cortinarius subfuscoperonatus (e HMJAU 44444, holotype; f HMJAU 44445). Scale bars: 2 cm (a, b, d-f). Photographs by Meng-Le Xie.

Figure 3. Basidiospores of three newly-described species. a Cortinarius laccariphyllus (HMJAU 44449, holotype); b Cortinarius neotorvus (HMJAU 44441, holotype); c Cortinarius subfuscoperonatus (HMJAU 44444, holotype). Photographs by Meng-Le Xie.

Figure 4. Margin cells of three newly-described species. a Cortinarius laccariphyllus (HMJAU 44449, holotype); b Cortinarius neotorvus (HMJAU 44441, holotype); c Cortinarius subfuscoperonatus (HMJAU 44444, holotype). Photographs by Meng-Le Xie.