Tricholoma lishanense L. Fan & J.J. Yang, 2023

Yang, Jia-Jia, Xu, Yu-Yan, Lv, Jing-Chong & Fan, Li, 2023, Tricholoma lishanense (Tricholomataceae, Agaricales), a new species from China revealed by morphology and phylogenetic analysis, Phytotaxa 598 (1), pp. 89-96 : 92-94

Tricholoma lishanense L. Fan & J.J. Yang , sp. nov. ( Fig. 2 )

MycoBank:—MB847576

Diagnosis:—differing from the phylogenetically and morphologically closest related species T. album by its abundant clamp connections, very narrow lamellae, pileus margin straight and seldom wavy in old fruit bodies.

Etymology:—‘ lishanense ’, refers to the type locality, where the type specimen was collected.

Holotype:— CHINA. Shanxi Province, Jincheng City, Qinshui County, Lishan Mt. , 1680 m elev., 24 August 2020, on the ground under Quercus sp. , N. Mao MNM 059 ( BJTC FM1023 ).

Description:— Basidiomata medium-sized, firm, fleshy. Pileus 30–90 mm, surface smooth, hemispherical or bellshaped with slightly inwardly rolled margin at first, then expanding with maturity to almost flat, whitish (#ffffff) to pale yellow (#f4f1e6), often with ochre-yellow (#c9a06f) centre when mature, glabrous, dry and dull, non-striate. Lamellae 1 mm broad, adnate, medium spaced to rather crowded, whitish (#ffffff) to cream (#f7f3e7), often lemon yellow (#ffff88) to pale yellow brown (#ddad79) spotted when bruised; lamellulae attenuate, arranged in 2–3 tiers. Stipe central, stuffed, 30–80 × 5–13 mm, cylindrical, mostly widened at base, more rarely tapering, smooth, whitish (#ffffff) to cream (#f7f3e7), turning pale yellow brown (#ddad79) when bruised. Context white, turning yellow when exposed. Odor faint but fragrant and pleasant. Taste not recorded. Spore print white.

Basidiospores [120/7/7] (3.9–)4.6–7.1(–7.6) × (2.6–)2.8–4.4(–4.6) μm, [Q = 1.35–1.92, Q av = 1.6 ± 0.14], ellipsoidoblong, colorless and smooth, with one large guttule and an oblique hilar appendage. Basidia 19–37 × 3.5–6.5 μm, swollen at the apical end and tapered toward the middle or base, mostly 4-spored, occasionally 2-spored, clavate to sub-cylindrical, with sterigmata up to 4.5 μm long. Cheilocystidia and pleurocystidia absent. Hymenophoral trama parallel, composed of cylindrical hyphae 5.5–10.5 μm broad. Pileipellis a cutis of cylindrical hyphae, hyphae smooth, 3.5–8.5 μm broad, radially arranged to slightly interwoven, colorless in KOH. Stipitipellis composed of parallelarranged hyphae, hyphae filamentous, thin-walled, colorless, 2.5–6.0 μm broad, terminal elements subcylindrical with round apex. Caulocystidia absent. Clamp connections present in all tissues.

Habit, habitat and distribution:—Solitary, scattered or gregarious, on the ground in oak forests, known from northern China.

Additional specimens examined:— CHINA. Shanxi Province, Jincheng City , Qinshui County, Lishan Ms., 35°29’ N, 112°1’ E, 1680 m elev., 24 August 2020, on the ground under Quercus sp. , N. Mao MNM059 ( BJTC FM1023 ), N. Mao MNM055 ( BJTC FM1020 ), H. Liu LH 1140 ( BJTC FM1000 ); ibid. 1626 m elev., 24 August 2020, on the ground under Quercus sp. , H. Liu LH 1104 ( BJTC FM968 ); ibid. 1675 m elev., 27 August 2020, on the ground under Quercus sp. , H. Y Fu FHYM002 ( BJTC FM1137 ); ibid. 1640 m elev., 25 July 2021, on the ground under Quercus sp. , N. Mao MNM333 ( BJTC FM1735 ); ibid. 26 July 2021, on the ground under Quercus sp. , N. Mao MNM376 ( BJTC FM1798 ).

Figures

FIGURE 2. Tricholoma lishanense. a. Basidiomata (BJTC FM1023, holotype). b. Basidiomata (BJTC FM1000). c. Basidiospores. d. Basidia. e. The clamp connections of pileipellis. Scale bars: a, b = 3 cm, c, e = 5 μm, d= 10 μm. Photos by: a, b Jin Zhong Cao; c–e Jia-Jia Yang.