Four new species of Mycena sect. Calodontes (Agaricales, Mycenaceae) from northeast China Author Liu, Zewei https://orcid.org/0000-0002-2700-0831 Shandong Key Laboratory of Edible Mushroom Technology, School of Agriculture, Ludong University, Yantai 264025, China Author Ge, Yupeng https://orcid.org/0000-0001-5754-201X Shandong Key Laboratory of Edible Mushroom Technology, School of Agriculture, Ludong University, Yantai 264025, China Author Zeng, Hui https://orcid.org/0000-0003-2025-844X Institute of Edible Mushroom, Fujian Academy of Agricultural Sciences, Fuzhou 350011, China & National and Local Joint Engineering Research Center for Breeding and Cultivation of Features Edible Mushroom, Fuzhou 350011, China Author Cheng, Xianhao https://orcid.org/0000-0002-5922-9913 Shandong Key Laboratory of Edible Mushroom Technology, School of Agriculture, Ludong University, Yantai 264025, China Author Na, Qin https://orcid.org/0000-0001-8406-6389 Shandong Key Laboratory of Edible Mushroom Technology, School of Agriculture, Ludong University, Yantai 264025, China naqin19890317@163.com text MycoKeys 2022 2022-09-27 93 23 56 http://dx.doi.org/10.3897/mycokeys.93.86580 journal article http://dx.doi.org/10.3897/mycokeys.93.86580 1314-4049-93-23 17E7093FE01A55C8966FD47E5BED2270 Mycena subulata Z.W. Liu, Y.P. Ge & Q. Na, sp. nov. Figs 13 , 14 , 15 Diagnosis. Pileus reddish-grey to dull red, slightly hygrophanous. Cheilocystidia thick-walled, slenderly fusiform with distinctly long and narrow protuberance. Stipitipellis a cutis, with projecting hyphae, caulocystidia thick-walled. Holotype. China. Heilongjiang Province: Liangshui National Nature Reserve, Yichun City, 47°13'13"N , 128°53'21"E , 21 August 2021, Zewei Liu, Yupeng Ge, Qin Na and Shixin Wang, FFAAS0423 (collection number MY0671). Etymology. Refers to cheilocystidia with distinctly long and narrow protuberance. Description. Pileus 9-32 mm in diam., convex to campanulate when young, hemispherical to applanate with age, margin sometimes wavy, slightly deflexed; at centre dull red (8C3), brownish-grey (8D2), greyish-brown (8D3), reddish-brown (8D4, 8E4-8E5) and dark brown (8F5), disc paler to reddish-grey (8B2, 9B2), brownish-grey (9C2), dull red (9B3, 9C3), greyish-magenta (13D3), margin light brown (7D4), brown (7E4) or dull red (9C3); striate none or indistinct, reddish-brown (8E4-8E5), towards the centre up to 1/5 diam.; surface dry, unclearly rugose or none, margin slightly hygrophanous. Context white, 1 mm thick, fragile. Lamellae sinuate to subdecurrent, 31-33 reaching the stipe, 1-3 tiers of lamellulae, white, irregularly intervenose, edge concolorous, wavy and slightly serrulate. Stipe 27-75 x 2-5 mm, central, cylindrical, apex to middle brownish-orange (7C3), dull red (8C3), brownish-grey (7D2), greyish-magenta (14D3), lower part brownish-grey (8C2), greyish-brown (8D3), reddish-brown (8D4), fragile, hollow, white granular near apex, base slightly swollen with white fibrils. Odour raphanoid, taste indistinct. Basidiospores (100/5/4) 6.0-6.7-7.3(7.9) x 3.3-3.8-4.3(4.6) μm [Q = (1.61)1.65-1.87(1.90), Q = 1.76 +/- 0.07] [holotype (40/2/1) (6.0)6.2-6.6-7.1 x 3.4-3.7-4.0(4.2) μm , Q = 1.65-1.87(1.90), Q = 1.78 +/- 0.07], elongated ellipsoid, colourless, smooth, thin-walled, amyloid. Basidia 23-34 x 5-6 μm , 4-spored, clavate, hyaline, sterigmata 2-3 μm in length. Cheilocystidia moderately thick-walled (0.5-0.6 μm ), hyaline, narrowly fusiform with long and narrow protuberance, 43-82 x 4-11 μm , protuberance 14-36 x 1-2 μm . Pleurocystidia absent. Pileipellis a cutis composed of three to four layers of cylindrical cells, 20-89 x 3-7 μm , smooth and thin-walled; terminal cells cylindrical, apically narrow, 24-61 μm in length, the apex 3-4 μm and base 4-7 μm in diam., thin-walled, hyaline. Hypodermium formed by fusiform to subglobose hyphae, 21-41 x 17-25 μm , thin-walled, hyaline. Lamellar trama subregular, dextrinoid. Stipitipellis a cutis composed of hyphae 3-8 μm in diam., smooth, thin-walled, with projecting hyphae 3-8 μm in diam.; caulocystidia 29-47 x 6-12 μm , clavate and apices tapered, thick-walled (0.5-0.6 μm ), smooth. Clamps present in all tissues. Habitat. Scattered on the litter layer in Pinus koraiensis , Larix gmelinii and Tilia sp. mixed forests. Known distribution. Heilongjiang Province, China. Additional material examined. China . Heilongjiang Province : Liangshui National Nature Reserve , Yichun City , 21 August 2021 , Zewei Liu, Yupeng Ge, Qin Na and Shixin Wang, FFAAS0419 (collection number MY0654); same location, 21 August 2021 , Zewei Liu, Yupeng Ge, Qin Na and Shixin Wang, FFAAS0420 (collection number MY0657) ; Heilongjiang Province : Taipinggou National Nature Reserve , Hegang City , 3 September 2021 , Shixin Wang, FFAAS0426 (collection number MY0795) . Notes. Cheilocystidia with a long and narrow protuberance is the key microscopic character that distinguishes M. subulata and is uncommon in sect. Mycena Calodontes ( Smith 1947 ; Maas Geesteranus 1992a , 1992b ; Grgurinovic 2003 ; Robich 2003 ; Chew et al. 2014 ; Aravindakshan and Manimohan 2015 ; Aronsen and Laessoe 2016 ; Na 2019 ; Liu et al. 2021 ). Mycena lammiensis Harmaja and M. pelianthina (Fr.) Quel . have similar cheilocystidia, but differ from M. subulata by their broader cheilocystidia with purplish-brown contents and having pleurocystidia ( Smith 1947 ; Robich 2003 ; Aronsen and Laessoe 2016 ). The cheilocystidia of M. subcorticalis (Cooke & Massee) Sacc. with a protuberance are similar to those of M. subulata . However, M. subcorticalis has larger and inamyloid spores, a gelatinised pileipellis and a stipitipellis with sparse excrescences ( Grgurinovic 2003 ). More rarely, mucronate cheilocystidia and absence of pleurocystidia have been described for M. pearsoniana and its clay pink pileus is similar to that of M. subulata , but M. pearsoniana differs in having a slightly glutinous pileus when wet and inamyloid spores ( Aronsen and Laessoe 2016 ; Na 2019 ). Other species that are macroscopically similar to M. subulata , namely M. luteovariegata , M. nullawarrensis and M. pura , can be distinguished by cheilocystidia shape and presence of pleurocystidia ( Perry 2002 ; Robich 2003 ; Grgurinovic 2003 ; Harder et al. 2013 ; Aronsen and Laessoe 2016 ; Na 2019 ). Figure 13. Basidiomata of Mycena subulata Z.W. Liu, Y.P. Ge & Q. Na a, b FFAAS0419 c, d FFAAS0420 e-g FFAAS0423 , holotype h FFAAS0426 Scale bars: 10 mm ( a-h ). Photographs a, b, e, f by Yupeng Ge c, d by Qin Na g by Zewei Liu h by Shixin Wang. Figure 14. Microscopic features of Mycena subulata ( FFAAS0423 , holotype) a-e basidiospores f basidia g-m cheilocystidia n lamellar trama o pileipellis and hypodermium p stipitipellis and caulocystidia. Scale bars: 5 μm ( a-e ); 10 μm ( f ); 20 μm ( g-p ). Figure 15. Morphological features of Mycena subulata ( FFAAS0423 , holotype) a basidiomata b basidia c basidiospores d cheilocystidia e stipitipellis and caulocystidia f pileipellis and hypodermium. Scale bars: 10 mm ( a ); 5 μm ( c ); 10 μm ( b, d-f ). Drawings by Zewei Liu.