Aleurodiscus globisporus S.H. He, 2025

Aleurodiscus globisporus S.H. He , sp. nov. MB 843409 View Materials . Fig. 2 View Fig .

Etymology: The species epithet “ globisporus ” refers to the globose basidiospores.

Typus: China, Guizhou Province, Yinjiang County, Fanjingshan Nature Reserve , on dead branch of Taxus chinensis , 12 Jul. 2018, S.H. He, He 5605 ( holotype BJFC 026667 About BJFC ) .

Basidiomes annual, resupinate, cupulate to effuse-reflexed with slightly elevated margin, adnate, easily separated from the substrate, coriaceous, small, up to 2 cm long, 1 cm wide, 400–500 µm thick. Hymenophore smooth, pruinose, light orange [5A(3–4)] to greyish orange [5B(3–6)], turning reddish brown in KOH, uncracked; margin slightly elevated and curved towards the hymenophore after drying, thinning out, slightly fimbriate, paler or concolourous with hymenophore. Context greyish white, up to 0.4 mm thick. Hyphal system monomitic; all hyphae with clamp connections. Subiculum indistinct; hyphae colourless, thick-walled, smooth, loosely interwoven, rarely branched, moderately septate, 2–4 µm diam. Subhymenium distinct, thickening; hyphae colourless, slightly thick-walled, smooth, moderately branched and septate, interwoven, more or less vertically arranged, 3–4 µm diam. Gloeocystidia moniliform, with several contractions at the apex, colourless, slightly thick-walled, smooth, with a basal clamp connection, SA–, embedded, 65–140 × 8–10 µm. Acanthocystidia numerous, variable in shape and size, mostly clavate, with many spines at the apical part, colourless, slightly thick-walled, with a basal clamp connection, embedded, 50– 85 × 5–25 µm. Hyphidia numerous, colourless, thin-walled, smooth, rarely branched. Basidia clavate, with many spines at the middle part, colourless, slightly thick-walled, with four sterigmata up to 25 µm long, with a basal clamp connection, 80–120 × 20–28 µm; basidioles numerous, in shape similar to basidia, but slightly smaller. Basidiospores subglobose to globose, with a prominent apiculus, colourless, with walls up to 1 µm thick, distinctly echinulate, strongly amyloid, acyanophilous, 18–24 × 17.5–22 µm, L = 20.4 µm, W = 19.7 µm, Q = 1.04 (n = 30/1).

Notes: Aleurodiscus globisporus is characterized by cupulate basidiomes, clamped generative hyphae, moniliform gloeocystidia, acanthocystidia and large, globose and echinulate basidiospores. In the phylogenetic tree, A. globisporus nested within the Aleurodiscus s. str. lineage, and is closely related to A. pinicola and A. penicillatus . Aleurodiscus pinicola is similar to A. globisporus in many aspects but differs in having simple-septate hyphae and slightly larger basidiospores (22.5–27.5 × 19–24 µm; Wu et al. 2019a). Aleurodiscus penicillatus differs from A. globisporus by having less distinct and shorter moniliform gloeocystidia (50–75 µm long) and smaller basidiospores (15–20 × 13– 17 µm; Núñez & Ryvarden 1997).