Vararia yunnanensis Y.L. Deng & C.L. Zhao, 2023

Deng, Ying-Lian & Zhao, Chang-Lin, 2023, The molecular phylogeny and morphology revealed a new wood-rotting fungus Vararia yunnanensis (Peniophoraceae, Russulales) in Yunnan Province, China, Phytotaxa 583 (1), pp. 39-49 : 44-45

Vararia yunnanensis Y.L. Deng & C.L. Zhao , sp. nov. Figs. 3 , 4

MycoBank no.: MB 844043

Holotype:— CHINA. Yunnan Province, Honghe, Pingbian County, Daweishan National Nature Reserve , E 103°30′10′′, N 23°42′07′′, elev. 1500 m, on fallen branch of angiosperm, 1 August 2019, CLZhao 17725 ( SWFC!), GenBank No. (ITS ON454115 ; nLSU ON502654 ).

Etymology:— yunnanensis refers to the location “ Yunnan Province ” where the type specimen was collected.

Diagnosis:— This species is characterized by the resupinate basidiomata with a cracking hymenial surface, a dimitic hyphal system with generative hyphae bearing simple-septa, and colorless, slightly thick-walled, smooth, amyloid basidiospores measuring 5–12 × 3.5–9 µm.

Basidiomata:— Basidiomata annual, adnate, resupinate, without odor or taste when fresh, up to 8 cm long, 4 cm wide, 80–100 µm thick. Hymenial surface smooth, cream (4A2/3), cracking with age. Sterile margin thin, cream (4A2/3).

Hyphal structure: — Hyphal system dimitic, generative hyphae bearing simple-septa, dichohyphae cream (4A2/3), capillary, thick-walled, dichotomously to irregularly branched with main branches and acute tips, weakly to moderately dextrinoid in Melzer’s reagent, CB–, tissues unchanged in KOH. Subiculum composed of colorless, generative hyphae rarely branched, slightly thick-walled, 1.5–2.5 μm in diam., dichohyphae predominate, frequently branched, 1.5 µm diameter. Subhymenium composed of colorless, generative hyphae rarely branched, slightly thick-walled, 1–2 µm diameter; dichohyphae predominate, frequently branched, 0.5–1.5 µm diameter;

Hymenium: — Gloeocystidia various with three types, (i) subcylindrical cystidia, colorless, thin- to slightly thickwalled, smooth, tapered or gradually elongated apex, 16.5–58.5 × 4–10 µm; (ii) tapering cystidia, usually with a constriction at the tip, colorless, thin- to slightly thick-walled, smooth, 27.5–42 × 5.5–9 µm; (iii) fusiform cystidia, colorless, thin- to slightly thick-walled, smooth, 18.5–43.5 × 7–9 µm. Basidia cylindrical, thin-walled, with four sterigmatas and a basal simple septum, 17.5–32 × 5–9.5 µm; basidioles dominant, in shape similar to basidia, but slightly smaller.

Basidiospores:— Ellipsoid, colorless, slightly thick-walled, smooth, with oil drops, amyloid, CB–, (5.1–)5.9– 11.5(–11.8) × (4.3–)4.7–8.6(–9) µm, L = 9.14 µm, W = 6.35 µm, Q = 1.4 (n = 60/2).

Additional specimen (paratype) examined: — CHINA. Yunnan Province, Honghe, Pingbian County, Daweishan National Nature Reserve , E 103°30′10′′, N 23°42′07′′, elev. 1500 m, on fallen angiosperm branch, 2 August 2019, CLZhao 18283 ( SWFC!), GenBank No. (ITS ON454116 , nLSU ON502653 ) .

Figures

FIGURE 3. Basidiomata of Vararia yunnanensis (CLZhao 17725). Bars: A = 0.5 cm; B = 0.5 mm. Photos by: Ying-Lian Deng.

FIGURE 4. Microscopic structures of Vararia yunnanensis (drawn from the holotype). A: Basidiospores. B: Basidia and basidioles. C: Subcylindrical cystidia. D: Tapering cystidia. E: Fusiform cystidia. F: Skeletal mycelium. G:A section of hymenium. Bars:A–G = 10 µm. Drawings by: Ying-Lian Deng.