Trechispora thailandica S.L. Liu, S.H. He & L.W. Zhou
MycoBank number: MB 559903; Index Fungorum number: IF 559903; Facesoffungi number: FoF 12883;
Basidiomes annual, resupinate, effused, thin, soft, easily separated from substrates, up to 9 cm long, 3 cm wide. Hymenophore grandinioid with round and obtuse aculei, white to cream when fresh, cream to buff-yellow with age, finely cracked with age. Margin thinning out as byssoid. Hyphal system monomitic; generative hyphae with clamp connections. Subicular hyphae hyaline, thin-walled, frequently branched and septate, subparallel, 2.5–5 µm in diam. Tramal generative hyphae distinct, hyaline, thin-walled, moderately branched, smooth, interwoven, 3–5 μm in diam. Cystidia absent. Crystals usually present, bipyramidic, aggregated. Basidia cylindrical with a slight median constriction, hyaline, thin-walled, with four sterigmata and a basal clamp connection, 11–15 × 4–5.5 µm; basidioles in shape similar to basidia, but slightly smaller. Basidiospores ellipsoid, hyaline to yellowish, thin-walled, aculeate, inamyloid, indextrinoid, acyanophilous, (3.5–)3.8–4.3(–4.5) × (2.5–)2.8–3.5 µm, L = 4 µm, W = 3 µm, Q = 1.3 (n = 60/2).
Material examined: THAILAND, Chiang Mai, Doi Saket, on rotten bamboo, 24 July 2016, S.H. He, He 4101 (holotype in BJFC 023542).
Notes: Trechispora thailandica resembles T. cyatheae by the white to cream, grandinioid hymenophore and ellipsoid basidiospores; however, T. cyatheae has smaller basidiospores (3–3.5 × 2–3 µm including spines) and grows exclusively on Cyathea glauca, an endemic species of tree fern to La Réunion, France (Ordynets et al. 2015).
Fig. 1. Basidiomes of Trechispora thailandica (He 4101, holotype). — Scale bars: a = 1 cm; b = 0.5 mm.
Fig. 2. Microscopic structures of Trechispora thailandica (drawn from the holotype). a. Vertical section through basidiomes showing position of b; b. Section through apex of a spine; c. Basidia; d. Basidiospores. — Scale bar = 10 μm.