Candolleomyces subminutisporus T. Bau & J.Q. Yan, 2021

Bau, Tolgor & Yan, Jun-Qing, 2021, Two new rare species of Candolleomyces with pale spores from China, MycoKeys 80, pp. 149-161 : 149

Candolleomyces subminutisporus T. Bau & J.Q. Yan sp. nov. Fig. 3

Etymology.

Referring to the small spores.

Holotype.

China. Henan Province: Boerdeng National Forest Park, Xinyang City, 16 July 2017, Tolgor Bau and Jun-Qing Yan, HMJAU37801 (holotype!).

Diagnosis.

Differs from C. sulcatotuberculosus in having smaller spores (5.8-6.8 μm long).

Description.

Pileus 8.0-22 mm, spreading hemispherically to broadly conical convex, hygrophanous, pale yellow-brown (6C7-6C8) at the centre, pale at the margin (6A2-6A4), striate from margin to centre, becoming pale brown (6B6-6B7) when dry. Veil present in early stages, thin, white (6A1), fibrillose, evanescent. Context thin and very fragile, 1.0-1.5 mm thick at the centre, same colour as the pileus. Lamellae 2.5-3.0 mm wide, adnate, moderately close, white (6B1) to pale coffee (6B2-6B3), edges saw-toothed under 20 × magnification. Stipes 15-40 mm long, 1.0-2.0 mm thick, cylindrical, hollow, white (6B1), sometimes subhyaline or slightly yellow-brown (6A2-6B2) at the base, apex pruinose, evanescent, slightly expanded at the base. Odour and taste indistinct.

Spores 5.8-6.8(7.8) × 3.8-4.9 μm, Q = 1.4-1.8, ovoid, ellipsoid to oblong-ellipsoid, in profile flattened on one side, rarely phaseoliform, inamyloid, smooth, very pale, nearly hyaline in water and 5% KOH, germ pore absent. Basidia 14-20 × 7.3-7.8 μm, 4-spored, clavate, hyaline. Pleurocystidia absent. Cheilocystidia 20-32 × 11-17 μm, utriform, with obtuse apex, bottom side tapering to the long or short stipe. Caulocystidia 27-42 × 6.1-9.8 μm, present at the apex, mostly solitary, various, similar to cheilocystidia or clavate and subcapitate or not. Trama of gills irregular. Pileipellis consists of 1-2 cells in a deep layer of the subglobose cell, up to 36 μm broad.

Habit and habitat.

Scattered on rotten wood or humus in Pinus massoniana and oak forests.

Other specimens examined.

China. Anhui Province: Huangshan City , 3 July 2018, Jun-Qing Yan, HFJAU1253, HFJAU1361 ; Guangxi Zhuang Autonomous Region: Qingxiushan National Forest Park, Nanning City , 12 Aug 2016, HMJAU37930; Phoenix Valley Forest Park , Nanning City , 17 Aug 2016, Jun-Qing Yan, HMJAU37950 ; Henan Province: Boerdeng National Forest Park, Xinyang City, 16 July 2017, Jun-Qing Yan , HMJAU37916, HMJAU37958; 17 July 2017, Jun-Qing Yan, HMJAU37959, HMJAU37960, HMJAU37961 : Hubei Province: Dagui Temple National Forest Park, Suizhou City , 16 July 2016, Tolgor Bau and Jun-Qing Yan, HMJAU37800 ; Jiangxi Province: Lushan Mountain, Jiujiang City , 30 June 2020, Jun-Qing Yan, HFJAU0921 ; Yunnan Province: Kunming Botanical Garden, Kunming City , 6 Aug 2016, Jun-Qing Yan, HMJAU37929 .

New combination

Figures

Figure 3. Basidiomata and microscopic features of Candolleomyces subminutisporus a-c Basidiomata d spores e basidia f pileipellis g cheilocystidia h caulocystidia. Scale bars: 10 mm (a-c); 10 μm (d-h).