Parasola kuehneri (Uljé & Bas) Redhead, Vilgalys & Hopple

Parasola kuehneri (Uljé & Bas) Redhead, Vilgalys & Hopple View in CoL , in Redhead, Vilgalys, Moncalvo, Johnson & Hopple, Taxon 50 (1): 235 (2001).

Figs 17 m – o View Figure 17 , 20 View Figure 20

Basionym.

Coprinus kuehneri Uljé & Bas , Persoonia 13 (4): 438 (1988).

Description.

Pileus 7–9 × 9–14 mm when still closed, up to 19 mm when mature, at first subglobose or ovoid, expanded pileus conical or occasionally flattened; dry; ochreous to red-brown at center, especially when young, usually with shades of gray at margin; at first with distinct longitudinal ridge at center, sulcate-striate up to 3 / 4 part from margin to center at age, sometimes with cracking edge. Context extremely thin, almost unseen in membrane part of pileus, whitish, young transparent light yellow or slightly brown-gray, brittle, odor and taste not distinctive. Lamellae rather crowded, free, 1–3 mm in wide, L = 46–53, I = 0 or 1, first white to beige, then become pale gray, brown-gray or gray, hardly deliquescent with age. Stipe 46–105 × 2 mm, cylindrical, hollow, almost equal or attenuate towards the apex, sordid white or cream, with brown or ochreous hue at bottom of stipe, glabrous; with white tomentose at base. Spore print not recorded.

Basidiospores (8.5 –) 9.3–10.5 (– 12.9) × (7.4 –) 7.9–8.7 (– 10.5) × (6.3 –) 6.5–6.9 (– 7.5) μm, Q 1 = 1.15–1.29, Q 2 = 1.30–1.52, av. Q 1 = 1.21, av. Q 2 = 1.44; strongly lentiform, round-angled triangular, rhomboid, ovoid or mitriform, usually with apical papilla and convex base in face view, ellipsoid to narrow ellipsoid in side view; smooth, yellow-brown to brown-black in water and red-brown in 5 % KOH, with yellow-brown oil droplet; inamyloid; germ pore eccentric, 1.7–2.8 μm in wide. Basidia dimorphic, 18–36 × 8–10 μm, with brachybasidia which are up to 15 μm in length, sterigma 3–6 μm, clavate, sometimes constricted in middle part, hyaline, 4 - or 2 - spored, surrounded with 4–7 pseudoparaphyses; subhymenium composed of ellipsoid, oblong or cylindrical elements, 12–28 × 8–17 μm. Cheilocystidia 33–55 × 14–23 μm, abundant, ellipsoid, fusiform or sublageniform, sometimes with a capitate apex, rarely globose, smooth, colorless, thin-walled. Pleurocystidia 46–76 × 17–33 μm, sublageniform or (sub) cylindrical, usually constricted in middle part. Lamella trama regular, 10–19 μm wide, hyaline, colorless, thin-walled. Pileipellis a hymeniderm at yellow-brown sulcate, mainly made up of clavate cells or rarely sphaeropedunculate cells, 25–43 × 13–18 μm, hyaline, with brown hue at base in most cases; other part of pileus with gray hue a cutis, made up of hyaline, almost colorless hyphae, 5–11 μm; pileus trama hyphae densely interwoven, thin-walled, hyaline, yellow-brown to brown, 3–7 μm wide. Sclerocystidia absent. Stipipellis hyphae parallel, 3–7 μm wide, hyaline, thin-walled, often diverticulate; hyphae of stipe trama 11–24 μm wide, colorless, thin-walled; caulocystidia unseen. Clamp-connection and pseudoclamps present.

Ecology.

Solitary, fasciculate, or in small groups, usually grow on soil in grassy place (especially near trunks) or soil-covered wood. Fruiting in June to August. Recorded with certainty from Netherlands, France, Germany, British, Poland and Italy in Europe ( Uljé and Bas 1988; Uljé 2005), Japan in Asia (treated as Coprinus plicatilis f. microsporus ) (Hongo and Aoki 1964); other reports also from North America and Oceania (f); only known from Jilin Province in China so far.

Specimens examined.

CHINA • Jilin Province, Changchun City, campus of Jilin Agricultural University , 43°81'50"N, 125°40'99"E, 147 m a. s. l., June 18 th 2021, L. Y. Zhu, HMJAU 60343 View Materials (Z 1) ; • same place as HMJAU 60343, June 19 th 2021, L. Y. Zhu, HMJAU 60344 View Materials (Z 2) ; CHINA • Jinlin Province, Jilin City, Jiaohe, Qianjin Forest Farm , 43°54'37"N, 127°38'57"E, 341 m a. s. l., July 22 nd 2022, L. Y. Zhu and H. B. Song, HMJAU 60078 View Materials (Z 22072231) GoogleMaps ; CHINA • Jilin Province, Jilin City, Jiaohe City, Shansong Ridge , 43°32'57"N, 127°08'07"E, 333 m a. s. l., July 25 th 2022, T. Bau, L. Y. Zhu and S. E. Wang, HMJAU 60077 View Materials (Z 22072530) GoogleMaps .

Notes.

Parasola kuehneri could be easily distinguished from other species in Parasola with its distinct pileus which have red-brown hue and longitudinal ridge at center. It is recorded that Parasola kuehneri from Europe have relatively small basidiospores (6.5–10.8 × 5.5–8.2 × 5.0–6.3 μm) which are sometimes heart-shaped and larger cheilocystidia and pleurocystidia which are up to 80 μm and 100 μm, respectively; besides, the European groups prefer to be terrestrial on naked soil that differs from our observations ( Uljé and Bas 1988; Uljé 2005; Schafer 2014). Parasola kuehneri was recognized as a variety of Parasola plicatilis ( Kühner and Josserand 1934; Hongo and Aoki 1964), while the latter have larger basidiospores (10.0–14.5 × 7.0–10.5 × 6.5–8.0 μm) (Uljé 2005).