Hygrophorus chrysodon (Batsch) Fr., Epicr.

Huang, Hong-Yan, Zhang, Wen-Hao, Huang, Ting & Tang, Li-Ping, 2021, Hygrophorus aurantiosquamosus (Hygrophoraceae, Agaricales), a new species of Hygrophorus section Chrysodontes from western China, Phytotaxa 528 (5), pp. 279-289 : 284-285

Hygrophorus chrysodon (Batsch) Fr., Epicr. syst. mycol. (Upsaliae): 320 (1838) [1836–1838] ( Figs. 3b, d , 4b, e–f , 5d )

The following description is adopted from Fries (1838) and Candusso (1997), as well as micro-morphology from our observations.

Description:— Pileus 3–8 (–10) cm diam., hemispherical, convex, plano-convex, with an inrolled margin; surface slightly viscid when moist, white to creamy, ivory, becoming golden yellow or yellowish cream, pale ochraceous at centre, covered with golden yellow patches or flakes; context white. Lamellae adnate, decurrent, arcuate, creamy white, yellowish cream. Stipe 3.5–10 cm long, 0.6–2 cm diam., subcylindrical, curved, stuffed, surface covered with pale golden yellowish fibrils, golden yellow floccules or flakes at the apex on a whitish background; context white. Odor not distinctive or faintly of fruit. Taste not distinctive.

Basidiospores [30/1/1] 7–9 × (3.8–) 4–5 μm, Q = (1.5–) 1.75–2.25, Q m = 1.96 ± 0.17, oblong to elongate, smooth under the light microscope and SEM, thin-walled, hyaline, non-amyloid. Basidia (36–) 38–50 (–54) × 6.5–8 μm, 4- spored, clavate, thin-walled; sterigmata up to 6 μm in length. Cheilocystidia 25–43 × 3–6 μm, thin-walled, colorless, scattered, contorted, gradually tapered toward the apex, occasionally branched. Pleurocystidia 20–45 × 3–7 μm, thin-walled, hyaline, scattered, irregularly shaped, spathulate, subcylindrical, subulate. Hymenophoral trama slightly divergent, non-gelatinized, made up of cylindrical hyphae 3–13 μm diam., and inflated elements, up to 29 μm diam., thin-walled, colorless and hyaline; subhymenial layer next to hymenium, non-gelatinized, composed of short elements 6–32 × 3–9 μm, cylindrical, irregularly shaped, thin-walled, colorless and hyaline. Pileipellis an ixotrichoderm, consisting of narrow hyphae 3–7 μm diam., loosely interwoven, branched or non-branched, thin-walled. Pileitrama made up of hyphae 7–15 (–20) μm diam., thin-walled, dense, slightly parallel. Stipitipellis a cutis, composed of hyphae 3–7 μm diam. Stipititrama made up of hyphae 4–12 μm diam., thin-walled, arranged in parallel. Mycelial hyphae 3–5 μm diam., smooth under the light microscope and SEM. Clamp connections present in all tissues.

Habit and habitat:—Gregarious or in small groups in mixed broadleaf-conifer forests, mainly including Abies and Fagus ; elev. below 2000 m; appearing in late summer to fall (August–November).

Distribution:—Currently known from Europe.

Material examined:— SWEDEN. Småland Province: Kristdala, Humlenäs , elev. unknown, 5 August 1979, N. Hakelier s. n. ( E00905347 , GenBank Acc. No.: ITS = OK104068 ) .

Figures

FIGURE 3. Basidiospores of Hygrophorus aurantiosquamosus and H. chrysodon. a, c from H. aurantiosquamosus (a from KUN-HKAS 80742, c from KUN-HKAS 53917); b, d from H. chrysodon (E00905347). Bars: a–b = 10 μm under light microscope, c–d = 1 μm under SEM. (Photos by: H.Y. Huang)

FIGURE 4. Basidiaandcystidia ofHygrophorus aurantiosquamosusand H.chrysodon.a–bBasidia;c,e Cheilocystidia;d,f Pleurocystidia. a, c–d from H. aurantiosquamosus (a, c from KUN-HKAS 49277, d from KUN-HKAS 80742); b, e–f from H. chrysodon (E00905347). Bars = 10 μm. (Photos by: H.Y. Huang)

FIGURE 5. Microscopic features of Hygrophorus aurantiosquamosus and H. chrysodon. a Lamellar trama; b–d Pileipellis; e–f Floccule on stipe. a–c, e–f from H. aurantiosquamosus (a–c from KUN-HKAS 80742, e–f from KUN-HKAS 49277); d from H. chrysodon (E00905347). Bars: a–b = 100 μm; c–f = 10 μm. (Photos by: H.Y. Huang)