Trechispora subsinensis S.L. Liu, S.H. He & L.W. Zhou.
MycoBank number: MB 559901; Index Fungorum number: IF 559901; Facesoffungi number: FoF 12881;
Basidiomes annual, resupinate, effused, thin, soft, fragile, easily separated from substrates, up to 9 cm long, 3 cm wide. Hymenophore odontioid with numerous small aculei, cream when fresh, straw-yellow to bluish grey when dry. Margin white, fimbriate, up to 0.5 mm wide. Hyphal system monomitic; generative hyphae with clamp connections. Subicular hyphae hyaline, thin to thick-walled, moderately branched and septate, subparallel to interwoven, 2–3.5 µm in diam, ampullate septa up to 5 μm wide. Aculei composed of a central core of compact hyphae and subhymenial and hymenial layers; tramal generative hyphae distinct, hyaline, thick-walled, moderately branched, smooth, subparallel to interwoven, 2–3.5 μm in diam. Cystidia absent. Crystals usually present, bipyramidic, aggregated. Basidia cylindrical with a slight median constriction, thin-walled, with four sterigmata and a basal clamp connection, 11–15 × 3.8–5 μm; basidioles similar in shape to basidia, but smaller. Basidiospores ellipsoid, hyaline, thin-walled, aculeate, inamyloid, indextrinoid, acyanophilous, (2.5–)2.7–3.5(–4) × (2–)2.3–2.8(–3) μm, L = 3 μm, W = 2.5 μm, Q = 1.2 (n = 90/3).
Material examined: CHINA, Guangdong, Guangzhou, Baiyunshan National Scenic Spot, on fallen angiosperm branch, 11 June 2019, L.W. Zhou, LWZ 20190611-9 (holotype in HMAS).
Notes: Trechispora subsinensis morphologically resembles T. chaibuxiensis, T. fimbriata, T. nivea and T. sinensis (Larsson 1995, Zhao & Zhao 2021), and phylogenetically these five species also nested within a strongly supported clade (BS = 97%, BPP = 1; Fig. 6). Trechispora chaibuxiensis differs in the presence of hyphoid cystidia, T. fimbriata in cracked hymenial surface and longer aculei (0.5–0.9 mm; Zhao & Zhao 2021), T. nivea in slightly thick-walled tramal hyphae and longer aculei (up to 1 mm; Larsson 1995), and T. sinensis in verrucose basidiospores.
Fig. 1. Basidiomes of Trechispora subsinensis (LWZ 20190611-9, holotype). — Scale bars: a = 1 cm; b = 1 mm.
Fig. 2. Microscopic structures of Trechispora subsinensis (drawn from the holotype). a. Vertical section of basidiomes; b. Hyphae in subiculum; c. Basidiospores. — Scale bar = 10 μm.