Aleurodiscus sichuanensis Sheng H. Wu

Wu, Sheng-Hua, Wei, Chia-Ling, Lin, Yu-Ting, Chang, Chiung-Chih & He, Shuang-Hui, 2019, Four new East Asian species of Aleurodiscus with echinulate basidiospores, MycoKeys 52, pp. 71-87 : 71

Aleurodiscus sichuanensis Sheng H. Wu sp. nov. Figs 2D, 6

Typification.

CHINA. SICHUAN PROVINCE: Wolungshan, Tengsheng, 2700 m, under bark of angiosperm, 11 Oct 2000, S.H. Wu & S.C. Wu, Wu 0010-18 (holotype TNM F12097). GenBank: ITS = MH596852, 28S = MF043534, TEF1 = LC269194.

Etymology.

sichuanensis (L.), referring to Sichuan Province, the type locality.

Diagnosis.

Aleurodiscus sichuanensis resembles A. oakesii in having acanthophyses, simple-septate generative hyphae, and gloeocystidia occasionally with protuberances. However, clamped hyphae are rarely present in A. oakesii . Protuberances of acanthophyses of A. oakesii are antler-like, while aculei of acanthophyses in A. sichuanensis are fairly small. Basidiospores of A. sichuanensis are D-shaped or broadly ellipsoid, while those of A. oakesii are ovoid-ellipsoid and slightly smaller (18-27 ×12–14(– 17) μm). Aleurodiscus sichuanensis , however, is most closely related to A. alpinus and differs from it by having acanthophyses and simple-septate hyphae.

Basidiomes resupinate, effused, adnate, membranaceous-subceraceous, 150-350 μm thick in section. Hymenial surface smooth, Buff or Buff Yellow, occasionally cracked; margin concolorous, determinate.

Hyphal system monomitic; hyphae simple-septate. Subiculum uniform, with dense texture, thin or up to 150 μm thick; hyphae interwoven, colorless, richly ramified, tortuous, usually full of small oily drops, 2.5-5.5 μm diam, thin-walled. Hymenial layer with dense texture, 100-200 μm thick; hyphae vertical, colorless, ± straight, 2.5-4.5 μm diam, thin-walled. Crystal masses scattered in subiculum, yellowish. Gloeocystidia numerous, immersed or projecting, yellowish or pale brownish yellow, cylindrical, narrowly clavate or tubular, with oily contents or homogeneous, SA+, basal or median portion occasionally with small aculei, 70-135 × 7-14 μm, with 0.5-1 μm thick walls. Acanthophyses numerous, irregularly cylindrical or narrowly clavate, sometimes subfusiform, colorless, apical parts with numerous aculei, 30-70 × 3 –8(– 12) μm (aculei excluded), thin-walled. Hyphidia numerous, occasionally branched, 35-85 × 2.5-4.5 μm. Basidia clavate, 4-sterigmate, 100-130 × 20-25 μm, with 0.8-1.2 μm thick walls. Basidiospores D-shaped or broadly ellipsoid, adaxially flattened, finely aculeate, thin-walled or 1-2 μm thick, sometimes with oily contents, amyloid, CB–, mostly 25.5-28.5 × 15-18 μm. (25 –)26–28.2(– 29) × (14.5 –)15.2–17(– 19) μm, L = 27.1 ± 1.0 μm, W = 15.9 ± 1.1 μm, Q = 1.71 (n = 30) (holotype, Wu 0010-18).

Ecology and distribution.

On dead branches of Quercus and other angiosperms at high elevations, China, Jul to Oct.

Additional specimens examined.

CHINA. SICHUAN PROVINCE: Wolungshan, Tengsheng, 2700 m, on angiosperm branch, 11 Oct 2000, S.H. Wu & S.C. Wu, Wu 0010-42 (TNM F12118). YUNNAN PROVINCE: Shangrila County, Pudacuo National Park, 3600 m, on dead branch of Quercus apuifolloides , 28 Jul 2017, S.H. He, He 4923, He 4926, He 4930, He 4935 (BJFC).