Mycena roseopurpurea J. W. Guo, Z. W. Liu, Y. P. Ge & Q. Na, 2025

Guo, Jingwen, Liu, Zewei, Zeng, Hui, Ge, Yupeng & Na, Qin, 2025, Three new species of Mycena sect. Calodontes (Mycenaceae, Agaricales) from Northeastern China, MycoKeys 125, pp. 51-79 : 51-79

Mycena roseopurpurea J. W. Guo, Z. W. Liu, Y. P. Ge & Q. Na sp. nov.

Figs 6 , 7 , 8

Diagnosis.

Pileus light pinkish-purple, light brown at center, hygrophanous when old. Cheilocystidia and pleurocystidia fusiform with tapered apices, thin-walled. Differ from M. subulata by lacking pleurocystidia and having acicular to lanceolate, thick-walled cheilocystidia.

Holotype.

China • Heilongjiang Province, Yichun City, Liangshui National Nature Reserve , 47°12'74"N, 128°52'86"E, 21 August 2021, Zewei Liu, Qin Na, Shixin Wang, and Yupeng Ge leg., FFAAS 3404 (collection no. MY 0660 ) .

Etymology.

Name refers to light pinkish-purple pileus.

Description.

Pileus 13–22 mm in diam., oblate hemispherical to plano-convex, with slightly depressed at center, margin wavy, occasionally cracked at mature; * Ecru-Drab ( XLVI 13 ′′′′ d), Light Drab ( XLVI 17 ′′′′ b) to * Drab-Gray ( XLVI 17 ′′′′ d) at center, gradually towards margin to Pale Verbena Violet ( XXXVI 55 ′′ f), Light Pinkish Lilac ( XXXVII 65 ′′ f), Pale Grayish Vinaceous ( XXXIX 9 ′′′ f), margin White ( LIII); striate Pale Smoke Gray ( XLVI 21 ′′′′ f), Pale Ecru-Drab ( XLVI 13 ′′′′ f) to * Ecru-Drab ( XLVI 13 ′′′′ d), towards the center up to 1 / 3 diam.; surface dry, hygrophanous when old. Context White ( LIII), 1.0 mm thick, fragile. Lamellae sinuate to subdecurrent, 21–28 reaching the stipe, 1–3 tiers of lamellulae, White ( LIII), irregularly intervenose, stretching downward to 1 / 3–3 / 4 of the width of lamellae, edge concolorous, wavy, serrated. Stipe 32–57 × 1–4 mm, central, cylindrical; apex Pale Drab-Gray ( XLVI 17 ′′′′ f), Pale Vinaceous-Drab ( XLV 5 ′′′′ d), Pale Brownish Drab ( XLV 9 ′′′′ d), lower part Pale Purple-Drab ( XLV 1 ′′′′ d), Light Purple-Drab ( XLV 1 ′′′′ b) to * Ecru-Drab ( XLVI 13 ′′′′ d), hollow, fragile; sparse White ( LIII) pubescent at base. Odor and taste raphanoid.

Basidiospores (100 / 5 / 4) (5.6) 5.9– 6.7 – 7.4 (7.8) × 3.0– 3.5 – 3.9 (4.1) μm [ Q = (1.70) 1.72–2.10, Q m = 1.90 ± 0.09] [ holotype (40 / 2 / 1) (6.0) 6.2– 6.7 – 7.4 (7.7) × 3.0– 3.5 – 3.9 (4.1) μm, Q = (1.71) 1.77–2.12, Q m = 1.93 ± 0.11], narrowly ellipsoid to cylindrical, colourless, smooth (1000 ×), thin-walled, amyloid. Basidia clavate, 18–31 × 4–7 μm, hyaline, thin-walled, 4 - spored, sterigmata 2–4 μm in length. Cheilocystidia fusiform, subfusiform, with apices tapered, 35–97 × 7–18 μm, thin-walled, smooth. Pleurocystidia similar to cheilocystidia, 30–80 × 6–18 μm, thin-walled, smooth. Pileipellis a cutis composed of cylindrical cells, 29–81 × 3–11 μm, smooth, thin-walled; terminal cells cylindrical, apex tapering, 20–99 μm in length, apex 2–4 μm, base 2–9 μm, thin-walled, hyaline. Hypodermium formed by fusiform to subglobose hyphae, 20–76 × 6–37 μm, thin-walled, hyaline. Lamellar trama subregular, dextrinoid. Stipitipellis a cutis composed of cylindrical hyphae, 4–17 μm in diam., smooth, thin-walled; caulocystidia fusiform, clavate, sometimes utriform, 23–66 × 6–20 μm, thin-walled, smooth. Clamps present in all tissues.

Habit and habitat.

Scattered on the litter layers in Betula platyphylla Suk. , Larix gmelinii , Pinus koraiensis , and P. syluestriformis (Takenouchi) T. Wang ex Cheng mixed forests during summer and autumn.

Known distribution.

Heilongjiang Province, Jilin Province, China.

Additional material examined.

China • Heilongjiang Province, Yichun City, Liangshui National Nature Reserve , 47°12'74"N, 128°52'56"E, 20 August 2021, Zewei Liu, Qin Na, Shixin Wang, and Yupeng Ge leg., FFAAS 3403 (collection no. MY 0635 ) ; • same location, 21 August 2021, Zewei Liu, Qin Na, Shixin Wang, and Yupeng Ge leg., FFAAS 3405 (collection no. MY 0668 ) . • Jilin Province, Yanbian Korean Autonomous Prefecture, Antu County, Erdaobaihe Town Beauty Pine Forest , 42°45'74"N, 128°14'41"E, 18 August 2021, Zewei Liu, Qin Na, Shixin Wang, and Yupeng Ge leg., FFAAS 3402 (collection no. MY 0625 ) .

Notes.

Mycena subulata , originally described from Heilongjiang province in China, can be easily mistaken for M. roseopurpurea due to morphological similarity, and growing on the humus layer of mixed forests of Larix gmelinii and Pinus koraiensis , but M. subulata is distinguished by acicular to lanceolate and thick-walled cheilocystidia ( Liu et al. 2022). Mycena pearsoniana , while having similar stipe color and lacking pleurocystidia, differs by subfusiform or clavate cheilocystidia and inamyloid basidiospores ( Smith 1947; Dennis 1970; Kost 2002; Harder et al. 2012; Aronsen and Læssøe 2016; Na 2019; Kwon et al. 2020). Mycena dura Maas Geesteranus & Hauskn. and M. subcorticalis (Cooke & Massee) Sacc. , reported from Europe and southern Australia, resemble M. roseopurpurea ; however, M. dura is distinctively characterized by its growth in grasslands and white stipe, and M. subcorticalis is distinguished by inamyloid basidiospores and gelatinized pileipellis ( Saccardo 1891; Maas Geesteranus and Hausknecht 1994; Grgurinovic 2003; Olariaga et al. 2015). Mycena pura differs by having light purple to purplish-red pileus and pinkish-purple to purple stipe ( Maas Geesteranus 1992 a, 1992 b; Perry 2002; Robich 2003; Thormann et al. 2006; Aronsen and Læssøe 2016; Na 2019; Okon et al. 2022; Liu 2023).

Figures

Figure 6. Basidiomata of Mycena roseopurpurea. A – C. Collection FFAAS 3405; D – G. Collection FFAAS 3404, holotype; H – J. Collection FFAAS 3403; K – L. Collection FFAAS 3402. Scale bars: 10 mm (A – E, G, I – J); 5 mm (F, H, K – L). Photographs (A – L) by Qin Na.

Figure 7. Microscopic features of Mycena roseopurpurea (FFAAS 3404, holotype). A – E. Basidiospores; F. Basidia; G – L. Cheilocystidia; M – R. Pleurocystidia; S. Pileipellis and hypodermium; T. Lamellar trama; U. Stipitipellis and caulocystidia. Scale bars: 5 μm (A – E); 15 μm (F); 30 μm (G – U). Structures (A – E) were rehydrated in 5 % KOH aqueous solution and (F – U) were stained in 1 % Congo red aqueous solution.

Figure 8. Morphological features of Mycena roseopurpurea (FFAAS 3404, holotype). A. Basidiomata; B. Basidia; C. Basidiospores; D. Cheilocystidia; E. Pleurocystidia; F. Stipitipellis and caulocystidia; G. Pileipellis and hypodermium. Scale bars: 10 mm (A); 15 μm (B); 5 μm (C); 30 μm (D – G). Drawings by Jingwen Guo.