Clitopilus lampangensis J. Kumla, N. Suwannarach & S. Lumyong

Kumla, Jaturong, Suwannarach, Nakarin, Sungpalee, Witchaphart, Sri-Ngernyuang, Kriangsak & Lumyong, Saisamorn, 2019, Clitopilus lampangensis (Agaricales, Entolomataceae), a new species from northern Thailand, MycoKeys 58, pp. 69-82 : 69

Clitopilus lampangensis J. Kumla, N. Suwannarach & S. Lumyong sp. nov. Fig. 3

Diagnosis.

Distinguished from other Clitopilus species by its pale yellow to grayish yellow pileus with the presence of caulocystidia, and from C. chalybescens by its wider caulocystidia, longer basidiospores, and lack of grayish blue color change on the pileus and stipe when bruised.

Etymology.

' lampangensis ', referring to Lampang Province, where the holotype was found.

Holotype.

THAILAND, Lampang Province, Mae Moh District, (18°24'21"N, 99°42'26"E, elevation 380 m), on ground in a tropical deciduous forest, May, 2018, J. Kumla & N. Suwannarach, SDBR-CMUJK 0147 and BBH 43590 (isotype).

Gene sequence (from holotype).

MK764933 (ITS), MK764935 (LSU) and MK784127 (rbp2).

Basidiocarps small, clitocyboid. Pileus 35-50 mm diam., initially convex or somewhat plano-convex with or without a central depression, becoming deeply umbilicate with age; surface pale yellow (4A3) to greyish yellow (4B5), somewhat velutinous, finely pruinose all over; margin incurved to slightly inrolled, entire or slightly wavy. Lamellae subdecurrent to decurrent, white (1A1), crowded, up to 2.5 mm wide, with lamellulae of 1-3 lengths; edge entire or slightly wavy, concolorous with the sides. Stipe 20-25 × 5-8 mm, central, solid; surface white (1A1) to yellowish white (4A2), finely pruinose all over, densely so towards the apex; base with white cottony mycelium. Odor strong farinaceous. A pale pinkish spore print.

Basidiospores 7.0-9.0 × 3.0-5.0 μm, Q = 1.40-2.33, Q = 1.82 ± 0.27, ellipsoid in polar view, amygdaliform to limoniform in side view, with 6-8 prominent longitudinal ridges, colorless, thin-walled. Basidia 17.0-25.0 × 4.0-8.0 μm, clavate, colorless, thin-walled, 2- and 4-spored; sterigmata up to 4 μm long. Lamella-edge fertile. Pleurocystidia and cheilocystidia absent. Lamellar trama subregular; hyphae 2.5-4.0 μm wide, hyaline, thin-walled. Pileus trama compact, hyaline, cylindrical hyphae 5-10 μm wide. Pileipellis a cutis of loosely interwoven hyphae; 3-5 μm wide, hyaline, thin-walled, and terminal cells; subcylindric or narrowly clavate, 4-8 μm wide. Stipitipellis at stipe apex a layer of repent, hyaline, cylindrical hyphae 4-8 μm wide, thin-walled. Caulocystidia 25.5-42.5 × 8.0-15.0 μm, single or clustered, erect or repent, varying in shape from cylindrical to clavate, hyaline, slightly thick-walled. Clamp connections absent in all tissues.

Ecology and distribution.

Fruiting solitary or gregarious on soil in a tropical deciduous forest. Known only from northern Thailand

Specimens examined.

THAILAND, Lampang Province, Mae Moh District, (18°24'20"N, 99°42'3"E, elevation 375 m), on ground in a tropical deciduous forest, May, 2018, N. Suwannarach & J. Kumla, SDBR-CMUNK 0047, GenBank sequence MK764934 (ITS), MK773856 (LSU) and MK784128 (rbp2).

Figures

Figure 3. Clitopilus lampangensis SDBR-CMUJK 0147 (holotype). A Basidiocarps B Basidiospores C Basidia D Pileipellis E Caulocystidia. Scale bars: 10 mm (A), 5 μm (B), 10 μm (C-E).