Pseudolepiota zangmui gen. et sp. nov. (Agaricaceae, Basidiomycota), a new white-spored mushroom from China Author Ge, Zai-Wei Author Yang, Zhu-Liang text Phytotaxa 2017 2017-07-07 312 2 247 255 http://dx.doi.org/10.11646/phytotaxa.312.2.7 journal article 10.11646/phytotaxa.312.2.7 1179-3163 13700047 Pseudolepiota zangmui Z. W. Ge sp. nov. ( Figs. 3–4 ) MycoBank MB820482 Etymology: This new species is named in honor of the late Prof. Mu Zang, for his great contribution to the knowledge of the larger fungi of China . Type:— CHINA . Yunnan Province : Xishuangbanna Autonomous Prefecture, Dadugang, in a mixed broad leaves forest of Fagaceae , 1350 m above sea level, 29 June 2008 , Z . W . Ge 2106 ( HKAS 54316, holotype ). Description: — Basidiomata small sized. Pileus 23–45 mm broad, hemispherical to convex at first, expanding to broadly convex to applanate with age, sometimes with appendiculate margin; surface covered with furfuraceous squamules of various brown: from pale red (7A3), brown (6E4), light brown (7D4-7D5), greyish brown (7D3-7 E3, 8 E3), reddish grey (7B2-8B2), brownish orange (7C3-7C4), dull red (8C3), reddish brown (8E4-8E5) to dark brown (6F5-6F6); furfuraceous squamules cover nearly all pileal surface at first, and remain intact at disc with development but elsewhere diffract with expansion and receding from pileus margin, exposing the whitish pileus context beneath. Lamellae free and remote from stipe with obvious gutter, white to off white, crowded, narrow, ≤ 4 mm wide, with 1-3 series of lamellulae; edge entire, white, not changing color or sometimes becoming grey (24E1) on bruising, becoming grey when dried. Stipe 30–45 × 3–6 mm , subcylindric, straight or curved, white, firm throughout development; surface below the annulus covered by easily detached band-like whitish, floccose squamules with pale red (7A3) to light brown (7D4-7D5) edges; surface above the annulus glabrous, white; stipe base occasionally with rhizomorphs ( Fig. 3A ). Context thick in pileus, white in pileus and stipe ( Fig. 3B ), not discoloring when bruised, with unpleasant odor. Taste mild. Spore print white. Basidiospores [120,6,4] (4.0)4.5–5.0(5.5) × 3–3.5 μm (mean 4.78 ± 0.32 × 3.22 ± 0.25 μm), Q = (1.29)1.43–1.67, Qav = 1.49 ± 0.1, ellipsoid, oblong in side view or in frontal view, apex rounded, smooth, hyaline to greenish white (27A2), congophilous, dextrinoid, usually with one guttule, without germ pore, slightly thick walled, becoming greyish magenta (14D4-14E4) to purplish red (14A6-14A7) in Cresyl blue. Basidia 18–22 × 5.5–6.5 μm, clavate, hyaline, four-spored. Cheilocystidia (13)18–36 × (5.0)8.0–12.5(13.0) μm, clavate, rarely broadly clavate to narrowly clavate, hyaline. Pleurocystidia not observed. Lamella trama regular to slightly interwoven, made up of subcylindrical hyaline hyphae, 7–10 μm diam. Pileal surface a subcutis layer made up of slightly interwoven cylindrical hyphae, (3)4– 6(8) μm in diam., thick walled, with brownish vacuolar pigments (occasionally interspersed with brown ones), wall brownish yellow; terminal elements mostly narrowly clavate. Stipe surface made up of regular to slightly interwoven, subcylindrical hyaline hyphae, (2.5)3.5–6(8) μm diam. Clamp connections absent. Habitat and distribution: —Saprotrophic, solitary to scattered, occasionally in clusters, terrestrial in Fagaceae forest. So far this is only known from Yunnan Province in southwestern China . Additonal material examined: — China , Yunnan Province , Xishuangbanna Autonomous Prefecture , Dadugang , in a mixed broad-leaved forest of Fagaceae , 1350 m above sea level , 29 June 2008 , Z . W . Ge 2107 ( HKAS 54317 , paratype ) ; the same place, 3 July 2008 ; Z . W . Ge 2175 ( HKAS 54385 , paratype ) ; the same place, 30 June 2014 , Z . W . Ge 3537 ( HKAS 84375 , paratype ) ; Puer City , Lancang County , Huimin town , Mengben village , scattered on the roadside in a mixed broad-leaved forest of Fagaceae , 1350 m above sea level , 23 August 2016 , Lancang-Hao 100 .