Marasmius vulgaris J. Q. Yan & H. Chen, 2025

Marasmius vulgaris J. Q. Yan & H. Chen sp. nov.

Fig. 4 View Figure 4

Etymology.

“vulgaris” means “common” or “usual”, refers to the fact that many known species in this genus share similar macroscopic characteristics with the new species.

Holotype.

China • ZheJiang Province, QingTian County, LiShui City , collected by Qin Na, Bin-Rong Ke, Zhi-Heng Zeng, 6 August 2021, HFJAU 2875 .

Diagnosis.

Marasmius vulgaris is mainly characterized by the rather small basidiomata, having a brownish orange, grayish orange pileus; with 3–5 tiers of lamellules; stipe white at apex, gradually darkening from the apex to the base, reddish brown towards base; basidiospores 13.5–16.0 × 3.0–4.0 μm, pleurocystidia abundant, narrowly fusiform, lageniform, which frequently have capitate, papillate, or constricted moniliform structures at apices; pileipellis and cheilocystidia in the form of broom-cells of the Siccus - type. It differs from M. confertus var. tenuicystidiatus Antonín by having bigger spores, which are up to 16.0 μm in length.

Description.

Pileus 10–30 mm, convex when young, then broadly conical to plane, smooth, with or without slightly obtuse umbo, brownish orange (7 C 4–5), grayish orange (5 B 3) at center, slightly paler to white towards margin, striate up to 2 / 3 from the margin. Context thin. Lamellae 2.0–3.0 mm broad, adnexed, ventricose, moderately close, white, with 3–5 tiers of lamellules, edges even, concolorous. Stipe 25–65 mm long, 1.5–2.0 mm thick, central, cylindric, rarely twisted, equal, fibrous, hollow, white at apex, gradually darkening from the apex to the base, reddish brown towards base, smooth, and the base covered with white mycelium.

Basidiospores (12.5) 13.5–16.0 (17.0) × 3.0–4.0 (4.5) μm (av = 14.8 × 3.8 μm), Q = (3.0) 3.3–5.0 (5.2), clavate or fusoid-clavate, often curved in profile, 3.0–4.0 μm broad, clavate in face view, smooth, colorless, hyaline, inamyloid, thin-walled. Basidia 25.0–35.0 × 4.5–6.5 μm, clavate, 4 - spored. Pleurocystidia 33.0–58.0 × 5.0–11.0 μm, narrowly fusiform, lageniform, frequently capitate, papillate, or constricted moniliform structures at apices. Cheilocystidia abundant, in form of Siccus - type broom cells, main body 13.0–26.0 × 4.0–11.0 μm, cylindrical to clavate, hyaline, thin-walled; apical setulae 4.0–13.0 × 1.0–2.0 μm, cylindrical to conical, subacute, yellow to pale yellow, thick-walled. Pileipellis hymeniform, mottled, composed of Siccus - type broom cells; main body 14.0–27.0 × 5.5–9.0 μm, clavate or pyriform, hyaline to pale yellow, thin- to thick-walled; apical setulae 4.0–10.5 × 0.8–1.5 μm, crowded, cylindrical, subacute, thick-walled. Lamellae trama interwoven, with hyphae 7.0–10.0 μm in diam, hyaline, dextrinoid, thin-walled. Stipitipellis a cutis composed of cylindrical hyphae 4.5–11.0 μm wide, parallel, smooth. Caulocystidia absent. Clamp connections present.

Habitat.

Scattered on soil in broad-leaved forest or mixed coniferous and broad-leaved forests.

Additional specimens examined.

China • JiangXi Province, Lushan National Nature Reserve , collected by Jing-Cheng Wu, Hong-Zhao Pan, 30 June 2019, HFJAU 0904 ; ZheJiang Province, SuiChang County, collected by Jun-Qing Yan, Yan-Liu Chen, 12 July 2020, HFJAU 1901 ; collected by Yu-Peng Ge, Bin-Rong Ke, Zhi-Heng Zeng, 14 July 2020, HFJAU 1976 ; ZheJiang Province, QingTian County, LiShui City , collected by Jun-Qing Yan, Ze-Wei Liu, 5 August 2021, HFJAU 2719 , HFJAU 2748 .

Note.

Based on molecular and morphological evidence, M. vulgaris belongs to subg. Globulares ser. Conferti ( Oliveira et al. 2020 b; Oliveira et al. 2024). Within this series, M. vulgaris is morphologically similar to M. confertus var. tenuicystidiatus , M. bondoi Wannathes, Desjardin & Lumyong , and M. graminipes . However, M. confertus var. tenuicystidiatus has smaller basidiospores (10–14 × 4.5–5.7 μm), a pruinose stipe apex, sometimes rostrate pleurocystidia ( Antonín et al. 2011); M. bondoi has a pruinose pileus surface, pleurocystidia with lobed apices, and the absence of papillate structures ( Wannathes et al. 2009 a); M. graminipes has larger basidiospores (18–21 × 4 μm) and the presence of caulocystidia ( Yang et al. 2013).

Morphologically, M. eyssartieri Antonín & Buyck and M. subtangerinus Antonín, Ryoo & H. D. Shin share similar morphological characteristics with the new species M. vulgaris , including basidiospores measuring 13–16 μm in length, the presence of pleurocystidia and pileipellis and cheilocystidia in the form of broom cells of the Siccus - type. However, M. eyssartieri differs in having a smaller pileus ( 5 mm), 0–1 tier of lamellulae, and clavate to occasionally rostrate pleurocystidia ( Antonín and Buyck 2006), while M. subtangerinus has 0–1 tier of lamellulae and clavate to rostrate pleurocystidia ( Antonín et al. 2011).

In addition, morphologically, M. rongklaensis Wannathes , M. subabundans Chun Y. Deng & T. H. Lim , and M. pseudoconfertus T. H. Li & Chun Y. Deng. have the aspect of M. vulgaris with similarly colored pileus and stipe. However, M. rongklaensis has smaller basidiospores (9–11 × 4.5–5.5 μm) and presence of cheilosetae and pileosetae ( Wannathes et al. 2019); M. subabundans has smaller basidiospores (7–9 × 3–4.5 μm) and absence of pleurocystidia ( Deng et al. 2012); M. pseudoconfertus has the slightly wider basidiospores (4–5 μm) and absence of pleurocystidia ( Deng et al. 2011).