Hygrophorus ochraceodiscus L. P. Tang & H. Y. Huang sp. nov.
Fig. 6
Chinese name.
赭色蜡伞.
Diagnosis.
Hygrophorus ochraceodiscus differs from its closest relative, H. brunneodiscus, by its darker centre, short basidia (24–42 × 6–10 μm), solitary to scattered growth habit and distribution currently restricted to the subalpine zone (ca. 2800 m) of Yunnan Province, south-western China.
Etymology.
Latin “ ochraceo- ” means ochraceous; “ discus ” means disc; “ ochraceodiscus ” refers to the characteristic ochraceous colouration of the pileus disc.
Type.
China • Yunnan Province: Shangri-La City (香格里拉市), Sanba Town (三坝乡), Mianshaba (绵沙坝), in mixed broadleaf-conifer forests dominated by Ericaceae, Fagaceae and Pinus yunnanensis, 27°21'14"N, 100°9'35"E, elev. 2755 m, 14 August 2020, T. Huang 490 (holotype: MHKMU HT-490, isotype: HMAS 354462, GenBank Acc. Nos.: ITS = PX 868482, nrLSU = PX 868379, tef 1 - α = PX 907486).
Description.
Basidiomata medium-sized. Pileus 4.5–6 cm diam., nearly flat with a broad umbo; margin uplifted; pale brown (4 B 3–4), greyish-brown to yellowish-brown (4 D 4–6), margin brownish-white (4 A 2); surface viscid, covered with glutinous slime; context up to 0.3 cm thick, white (1 A 1). Lamellae 0.4–0.5 cm wide, adnate to decurrent, slightly close, with 50–60 full lamellae per pileus; lamellulae numerous, narrowed; white (1 A 1). Stipe 6–8 cm long, 0.8–0.9 cm diam., central, cylindrical, tapered towards base; apex covered with white punctations, overall sheathed by thick glutinous slime; surface white (1 A 1); context fibrous, white (1 A 1).
Basidiospores [60 / 2 / 2] 7–9 (– 9.5) × 4.5–5.5 (– 6) μm, Q = 1.38–1.64 (– 1.7), Q m = 1.54 ± 0.08, ellipsoid, occasionally oblong, smooth, thin-walled, hyaline, inamyloid. Basidia 24–42 (– 50) × 6–10 (– 12) μm, clavate, slender, thin-walled, 4 - sterigmate; sterigmata up to 5 μm long. Cystidioid elements on the lamellar edges and sides 24–45 × 3–8 μm, thin-walled, hyaline, scattered, apically pyriform, branched, flexuous, irregularly-shaped. Hymenophoral trama slightly divergent, non-gelatinised, composed of cylindrical hyphae (4–17 μm diam.) and inflated elements up to 28 μm diam., thin-walled, hyaline. Subhymenial layer next to hymenium, not gelatinised, composed of short cylindrical to irregularly-shaped elements, 6–39 × 4–9 μm, thin-walled, hyaline. Pileipellis an ixotrichoderm, gelatinised, consisting of narrow, interwoven hyphae 2–5 μm diam., thin-walled, branched or unbranched. Pileal trama of slightly parallel, dense hyphae 2–17 μm diam., thin-walled. Stipitipellis an ixotrichoderm, hyphae 2–8 μm diam., thin-walled. Floccules (at stipe apex) of compact, erect, branched hyphae 2.5–8 μm diam., with cylindrical to slender clavate terminal elements 25–70 × 4–7 μm, thin-walled. Stipititrama of parallel, thin-walled hyphae 3–20 μm diam. Mycelial hyphae 2–5 μm diam., smooth. Clamp connections present in all tissues.
Known distribution.
Yunnan Province, China.
Habit and habitat.
Solitary or scattered in mixed broadleaf-conifer forests dominated by Ericaceae, Fagaceae and Pinus yunnanensis; elev. ca. 2800 m; fruiting in late summer (August).
Additional material examined.
China • Yunnan Province: Shangri-La City (香格里拉市), Sanba Town (三坝乡), Mianshaba (绵沙坝), in mixed broadleaf-conifer forests dominated by Ericaceae, Fagaceae and Pinus yunnanensis, 27°21'14"N, 100°9'35"E, elev. 2755 m, 14 August 2020, T. Huang 489 (paratype: MHKMU HT-489).
Notes.
This species is phylogenetically closely allied with H. brunneodiscus C. Q. Wang & T. H. Li, which it closely resembles morphologically. Although both species share similar basidiospores, H. brunneodiscus differs in having slightly smaller and more slender basidiomata (pileus 2–5 cm diam., stipe 4–9 × 0.4–0.7 cm), subdistant lamellae (36–40 full lamellae per pileus) and a distribution restricted to low-elevation habitats in Hunan and Shanxi Provinces (Wang et al. 2020, 2023; Zhang et al. 2024).
Publication Date: 2026-06-17