Volvopluteus deliciosus Chuan H. Li & T.H. Li, 2025

Li, Chuanhua, Zhang, Ming, Li, Jipeng & Li, Taihui, 2025, Volvopluteus deliciosus sp. nov. (Pluteaceae, Agaricales), a new edible species from Xinjiang, China, Phytotaxa 683 (3), pp. 253-262 : 257-260

Volvopluteus deliciosus Chuan H. Li & T.H. Li , sp. nov. Figs. 2–4

MycoBank:—MB 830551

Etymology:—The epithet “ deliciosus ” refers to the delicious taste and edibility of the new taxon.

Diagnosis:—Distinguished by white to greyish white pileus, pure white stipe, membranous volva, relatively large basidiospores sized 12.5–16.5 × 7.5–10 μm, and usually fusoid-ventricose but variably shaped pleurocystidia and cheilocystidia.

Holotype:— CHINA. Xinjiang Uygur Autonomous Region: Bayingol Mongolian Autonomous Prefecture , Yuli County, 87º48'51.37"E, 40º39'59.29"N, elev. 832 m, 13 June 2018, Chuanhua Li. (Holotype, GDGM73195 , GenBank nos.: MK944281 for ITS and MN056508 for nrLSU).

Description:— Basidiomata agaricoid and stipitate, medium to large sized. Pileus 5–11 cm broad, campanulate to hemispherical when young, convex to plane with age, sometimes with a broad and low umbo at centre, white, yellowish white to pale yellow (1A1–1A3–4A2) when young, greyish, greyish yellow to somewhat greyish grey (1B2–1B3) when mature, usually more greyish towards centre, slightly viscid when wet, often with soil from habitat adhering to surface, glabrous when young, then radially fibrillose to slightly squamulose, striate especially when matured; margin entire when young, somewhat rimose when matured. Context 7–14 mm thick at stipe, fleshy, soft, white to weakly pinkish, unchanging to becoming weakly pinkish-brownish when wounded. Lamellae free, pinkish white to pink (8A2–13A3) when young, then reddish brown to dull red (9D4–10C4), ventricose, crowded, 12–15 per cm at pileus margin, 11–14 mm wide, with lamellulae; edge nearly entire to finely serrulate. Stipe 8–14 cm long, usually longer than the pileus diameter, 0.8–1.8 cm thick at apex, 0.6–1.7 cm thick at middle, 2–2.7 cm at base, central, cylindrical to clavate, enlarged downwards, solid, glabrous, pure white to very weakly pinkish; base enlarged, somewhat bulbous; context white to weakly pinkish, unchanging to becoming weakly brownish when wounded. Volva 2–3 cm high, usually constricted, rarely saccate, membranous, thin, white, appearing greyish due to soil adhering to surface, glabrous or nearly so, occasionally partially adhering to the middle of stipe as residuals. Taste good and odour indistinctive. Spores print pinkish to pink.

Basidiospores 12.5–16.5 × 7.5–10 μm (x=14.17 × 8.89 μm, n=30, Q=1.42–1.87), ellipsoid, subellipsoid to ovoid, smooth, usually with 1–2 guttulae. Basidia 42–65 × 13–16 μm, clavate, hyaline, usually multiguttulate, 4-spored, with sterigmata 3.7–5 μm long, clampless at base. Pleurocystidia 62–88 × 12–33 μm, fusoid–ventricose, narrowly utriform to fusoid, clavate, enlarged at apex or constricted at base, hyaline, thin-walled. Lamellar edges sterile. Cheilocystidia 50–65 × 18–32 μm, lageniform, fusoid-ventricose to fusoid, sometimes clavate, hyaline, thin-walled. Lamellar trama hyphae 5–42 μm broad, hyaline, without pigment. Pileipellis a thin ixocutis, gelatinized, composed of hyphae 7.5–10 μm wide, cylindrical or irregular in outline, hyaline, thin-walled. Pileocystidia 75–263 × 20–55 μm, fusoid-ventricose to fusoid, rarely clavate to obclavate, fusoid to utriform, rarely with two apical or subapical branches or prongs at apex, hyaline, thin-walled. Stipitipellis a cutis; hyphae 5–17.5 μm wide, cylindrical or flexuose, hyaline, thin-walled. Caulocystidia 50–78 × 20–25 μm, utriform, fusoid-ventricose, hyaline, thin-walled. Volva composed of densely interwoven cylindrical hyphae, hyphae 4.5–17 μm wide. Clamp connections absent in all tissues.

Habit, babitat, distribution and season: —Solitary or scattered on sandy soil in cotton fields; Yuli County, Bayingol Mongolian Autonomous Prefecture, Xinjiang Uygur Autonomous Region, China. 13 June 2018. From July to September, the local temperature is around 21–32℃ in the basidiomal growing time.

Additional specimens examined: — China. Xinjiang Uygur Autonomous Region: Bayingol Mongolian Autonomous Prefecture , Yuli County, 87º48'50.32"E, 40º40'00.44"N, elev. 833 m, 13 June 2018, Chuanhua Li. (SIEFXJ20180613!) ; Chuanhua Li. ( GDGM74751 , GDGM76075 and GDGM76076 ) .

Figures

FIGURE 2. Habitat and macro-morphology of Volvopluteus deliciosus. A: Habitat. B–D: Basidiomata (B: GDGM73195, holotype; C: SIEFXJ20180613; D: GDGM74751).

FIGURE 3.Micro-morphology (photos)of Volvopluteusdeliciosus.A–C:Basidiospores.D:Basidiole.E:Pleurocystidia.F:Cheilocystidia. G: Lamellar trama hyphae. H: Pileipellis. I: Caulocystidia.

FIGURE 4. Microscopic features of Volvopluteus deliciosus. A: Basidiospores. B: Basidioles with basidium. C: Pleurocystidia. D: Cheilocystidia. E: Caulocystidia. F: Pileocystidia. Bars: A–B=10 μm, C=20 μm, D=10 μm, E–F=20 μm.