Lactifluus hezhangensis sp. nov. (Russulaceae, Russulales) from Southwest China Author Chen, A-Min 0000-0002-0412-2107 College of Agriculture, Guizhou University, Guiyang 550025, Guizhou, China. & The Vegetable Research Institute, Guizhou University, Guiyang 550025, Guizhou, China. & camcamaa @ 126. com; https: // orcid. org / 0000 - 0002 - 0412 - 2107 Author Pei, Yun 0000-0001-7730-4561 College of Agriculture, Guizhou University, Guiyang 550025, Guizhou, China. & The Vegetable Research Institute, Guizhou University, Guiyang 550025, Guizhou, China. & 292241195 @ qq. com; https: // orcid. org / 0000 - 0001 - 7730 - 4561 292241195@qq.com Author Wen, Ting-Chi 0000-0003-1744-5869 The Engineering Research Center of Southwest Bio-Pharmaceutical Resources, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou, China. & The Mushroom Research Centre, Guizhou University, Guiyang 550025, China & tingchiwen @ yahoo. com; https: // orcid. org / 0000 - 0003 - 1744 - 5869 tingchiwen@yahoo.com Author Hapuarachchi, Kalani Kanchana 0000-0002-5946-4526 The Engineering Research Center of Southwest Bio-Pharmaceutical Resources, Ministry of Education, Guizhou University, Guiyang 550025, Guizhou, China. & kalanifirst @ yahoo. com; https: // orcid. org / 0000 - 0002 - 5946 - 4526 kalanifirst@yahoo.com Author Xu, Xiu-Hong 0000-0002-6602-4246 The Vegetable Research Institute, Guizhou University, Guiyang 550025, Guizhou, China. & College of Tobacco Science, Guizhou University / The Key Laboratory for Tobacco Quality of Guizhou Province, Guiyang 550025, Guizhou, China. & 25725861 @ qq. com; https: // orcid. org / 0000 - 0002 - 6602 - 4246 25725861@qq.com Author Zhang, Wan-Ping 0000-0002-2029-6844 College of Agriculture, Guizhou University, Guiyang 550025, Guizhou, China. & The Vegetable Research Institute, Guizhou University, Guiyang 550025, Guizhou, China. & zwp 269 @ 126. com; https: // orcid. org / 0000 - 0002 - 2029 - 6844 text Phytotaxa 2022 2022-12-13 575 3 253 264 http://dx.doi.org/10.11646/phytotaxa.575.3.3 journal article 208110 10.11646/phytotaxa.575.3.3 6762193f-c320-477e-9107-d43bab5fefb5 1179-3163 7431176 Lactifluus hezhangensis W.P. Zhang, A.M. Chen & X.H. XU , sp. nov. ( Fig 2 ) MycoBank No. : MB 840661 Type :— CHINA . Guizhou Province : Bijie City , Hezhang ( 27.139ºN , 104.877ºE , 1700 m ), 12 July 2018 , Xiuhong XU holotype HKAS 1159035 !, isotype HMAS 292389, Sequences from the strain HKAS 1159035 and HMAS 292389 have been deposited in GenBank with accession numbers: ITS= MZ621154 - MZ621155 , LSU= MZ621156 - MZ621157 , RPB2= MZ666103 - MZ666104 . Etymology :—Refers to the collection site “Hezhang”. Known distribution :—Hezhang, Bijie, Guizhou Province , China . Description :— Pileus 50–55 mm diam, dry, light brown (B5651D), rough when old, most obvious at the concave; uneven color, light brown (B5651D) to blackish brown (#654321), paler toward margin; pruinose near centre, margin entire, decurved. Lamellae decurrent, white (W3C) to cream (#FFF9E3), thick and brittle, 3–5mm broad, edge concolorous to marginate, with 1–3 lamellulae located between two lamellae. The attachment to the stipe varies from adnate, adnate with a decurrent tooth to decurrent. Stipe 28–30 × 10–12 mm , hollow, dry, rough, concolorous with pileus, white at base, centralis or lateralis, tapering downwards or curved near the base. Spore deposit white. Latex white, unchanging when exposed to the air Context white (W3C) (#FFFFFF), mild. Basidiospores (4.79) 5.06–7.22(7.30) × (4.67) 4.68–6.20 (6.59) μm; (Q= (1.01) 1.02–1.32(1.38) μm, subglobose to ellipsoid, hyaline, with a strongly amyloid ornamentation composed of interconnected warts forming a complete reticulum up to1.0 µm high. Basidia (35)37–47(48) × 9–12 μm, four-spored, sterigmata1.7–2.48μm long. Pleurocystidia absent. Marginal cells (22)23–31(33) × (3)4–7(–8) μm, Q= (3.44)3.54–7.43(7.35), Q=5.00 ± 1.50, fusoid, sometimes flexuous, thin-walled, hyaline. Hymenophoral trama subregular composed of scattered cylindrical, 2–3 μm diam, thin-walled hyphae and abundant. Pseudocystidia 5–8 μm diam. Pileipellis a palisade, 20–35 µm thick; suprapellis composed of subcylindrical to conical terminal elements, 20–47.5 × 2.5–10 µm, 1- or 4-septated, tapering towards apex, with brown; subpellis composed of 2–4 layers of cells, 10.5–16 × 9–14 µm, thin-walled. Stipitipellis a trichopalisade, 10–42 µm thick, terminal elements 9–15.5 × 2.1–5.2 µm, subcylindrical, often tapering towards apex, thin-walled, septated. Habitat :—Gregarious, Growing on the grassland in a coniferous forest. Specimens examined :— CHINA . Guizhou Province : Bijie City , Hezhang (N 27º08.317ʹ E 104º52.633ʹ 1700 m ), on the grassland in a coniferous forest, 12 July 2018 , Xiuhong XU ( holotype HKAS 1159035!, isotype HMAS 292389) .