Three new species of Tricholomopsis (incertae sedis) from North China based on morphological and molecular data Author Mao, Ning 0000-0003-1564-9446 College of Life Sciences, Capital Normal University, Xisanhuanbeilu 105, Haidian, Beijing 100048, China & 373898825 @ qq. com; https: // orcid. org / 0000 - 0003 - 1564 - 9446 373898825@qq.com Author Xu, Yu-Yan 0000-0003-2501-5607 College of Life Sciences, Capital Normal University, Xisanhuanbeilu 105, Haidian, Beijing 100048, China & 1335805640 @ qq. com; https: // orcid. org / 0000 - 0003 - 2501 - 5607 1335805640@qq.com Author Fan, Li 0000-0001-9887-7086 College of Life Sciences, Capital Normal University, Xisanhuanbeilu 105, Haidian, Beijing 100048, China & fanli @ mail. cnu. edu. cn; https: // orcid. org / 0000 - 0001 - 9887 - 7086 fanli@mail.cnu.edu.cn text Phytotaxa 2021 2021-06-09 507 2 155 166 http://dx.doi.org/10.11646/phytotaxa.507.2.3 journal article 10.11646/phytotaxa.507.2.3 1179-3163 5425603 Tricholomopsis galeata L. Fan & N. Mao , sp. nov. ( Figs. 2 , 3 ) MycoBank :—MB839211 Diagnosis:— Pileus 50–130 mm broad, light orange, covered with red fibrillose scales, basidiospores broadly ellipsoid to ellipsoid, Q = (1.11–) 1.25–1.67 (–2.0), cheilocystidia clavate-shaped, pleurocystidia absent. Etymology :—‘ galeata ’, helmet, refers to the shape of pileus. Holotype :— CHINA . Shanxi Province , Yicheng County , Shihe Forest Farm , 35°29’35’’N , 112°5’41’’E , elev. 1,960 m , 26 August 2020 , on a dead tree trunk in a coniferous forest dominated by Pinus sp . , H . Liu LH 1196 ( BJTC FM1107 ). Description:— Basidiomes growing singly or in clusters. Pileus 50–130 mm diam, helmet-like to convex with lightly inrolled margin, margin cracking with age, dry, light orange (#8b4513), densely covered with small, red to purple reddish (#e08796) fibrillose scales. Context yellowish, thin to slightly thick. Lamellae 3.5–5.5 mm broad, free to adnate, crowded, pale yellow (#ffffeb), edge entire; lamellulae in 3–4 tiers, concolorous with lamellae. Stipe 35–120 × 12–20 mm , cylindrical, hollow, straight to curved, smooth, dry, pale red (#ffcocb), pale orange (#ffe59a) to light orange (#8b4513), often staining purple especially when young. Taste not recorded. Smell indistinct. Spore print white. Basidiospores [30/2/2] (4–) 5–7 (–8) × (3–) 4–5 (–6) μm; [Q = (1.11–) 1.25–1.67 (–2.0), avQ = 1.48 ± 0.21]; broadly ellipsoid to ellipsoid, smooth, thin-walled, hyaline, usually containing one large oil droplet. Basidia 30– 40 × 6–8 μm, (2–)4-spored, cylindrical to narrowly clavate; with basal clamp connection; sterigmata 4–7 μm long. Cheilocystidia prominent, large, often in clusters, (45–) 55–105 (–126) × 13–23 (–27) μm, mostly narrowly clavate to lageniform-fusiform, slightly thick-walled, hyaline, or filled with yellow granular pigment. Pleurocystidia absent. Lamellar trama regular, composed of parallel hyphae 3–18 μm diam, cylindrical to slightly inflated, hyaline or with a fine pale yellow (#ffffeb) granular intracellular pigmentation. Pileipellis a cutis, composed of densely arranged parallel hyphae, 3–10 μm diam, with yellow to brown intraparietal and homogeneous or finely granular intracellular pigment, hyphae becoming erect and forming fascicles at intervals. Stipitipellis a thin cutis of parallel cylindrical hyphae of 5–15 μm diam, with hyaline to pale yellow-brown content. Clamp connections present in all tissues. Habit, habitat and distribution:—found growing on a dead tree trunk in a coniferous forest dominated by Pinus sp . , so far only known from Shanxi Province , China . Additional specimens examined:— CHINA . Shanxi Province , Yicheng County , Shihe Forest Farm , 35°29’34’’N , 111°53’59’’E , elev. 1,927 m , 20 August 2019 , on the trunk of a dead tree in a coniferous forest dominated by Pinus sp . , C . Yang YCM013 ( BJTC FM637 ). ibid . Yuanqu County , Lishan Mountain , Zhongcun Forest Farm , 35°29’7’’N , 112°25’5’’E , elev. 1,680 m , 15 July 2020 , on fallen wood in a forest of Pinus sp . , H . Liu LH 919 ( BJTC FM1229 ) .