taxonID	type	description	language	source
03BFA511C27FFFE42E9B3F3FFBA2FC92.taxon	etymology	Etymology: — the epithet, microsporum, refers to the small basidiospores compared to those of the other Porotheleum species described so far. Type: — CHINA. Shandong Province: Ji’nan City, Quancheng Park, on the trunk of Salix babylonica L., elev. 47 m, 4 September 2023, P. M. Wang 219 A (EFHAAU 10566, holotype!). [GenBank accession numbers — ITS: PP 576323, LSU: PP 576335; all from holotype]. Description: — Basidiomata (Fig. 2 a) on the trunk of Salix babylonica. Pileus small, omphalinoid, (3) 5 – 20 (2.5) mm diam., convex to applanate at first, then planoconvex with the centre depressed; surface smooth, greasy; center pale ochre-yellow (5 A 3 – 5 C 3), elsewhere yellowish (5 A 1 – 5 A 2), or pale-yellow (4 A 1 – 4 A 2), subviscid to viscid when wet; transparently sulcate when moist, slightly translucently furrowed to the centre, involute. Lamellae cream to yellowish white (2 A 2); edge even, thick, distant, at the bottom slightly intervenose, decurrent, with interspersed lamellulae of various lengths. Stipe central, (2) 5 – 18 (29) × 0.5 – 2 (2.5) mm, cylindrical to tapering upwards, near lamellae pale-yellow (5 A 2), basal part reddish-brown (5 E 2) to dull dark (red-) brown (5 E 6); surface not viscid. Context thin, whitish to pale-yellow (4 A 1 – 4 A 2). Odour non-distinctive, taste mild. Basidiospores (Fig. 2 b) [82 / 10 / 4] (4.4) 4.8 – 7.4 (7.75) × (2.6) 3.0 – 4.5 (4.8) μm (X = 6.1 ± 0.80 × 4 ± 0.47 μm), Q = (1.23) 1.33 – 1.85 (1.93), (Q m = 1.53 ± 0.15), ellipsoid, smooth, thin-walled, hyaline, cyanophilic, congophilic, nonamyloid. Basidia (Fig. 2 d) 16 – 40 × 4.5 – 7 μm, narrowly clavate, thin-walled, 2 - spored, long claviform, sterigmata up to 6 μm long. Hymenial cystidia absent. Hymenophoral trama composed of colourless, thin-walled cylindrical filamentous hyphae, 3 – 10.5 μm wide. Pileipellis (Fig. 2 c), a cutis composed of wide hyphae, 3.5 – 7.5 (9) μm wide., slightly thick-walled, subcylindrical to fusiform, brownish, brown to yellow tawny, pileocystidia absent. Subcutis consists of colourless, thin-walled, subcylindrical to fusiform, 6 – 13.5 μm wide, with scattered small crystals. Stipitipellis (Fig. 2 e) a trichoderm composed of caulocystidia and hyphidia; caulocystidia (Fig. 2 f) narrowly lageniform, narrowly fusiform or narrowly conical, fusoid-lanceolate, yellow-brown, thick-walled, 10 – 40 × 4 – 8 μm; hyphidia abundant, thin-walled, unbranched, 2 – 5 μm wide. Clamp connections present in all parts of basidiomata. Habitat (Ecology): — Ecology saprobic; growing alone or gregariously on the trunks of Salix babylonica distributed in Quancheng Park (Ji’nan City, Shangdong Province, China) at an elevation of 47 m. Distribution: — currently known only from Quancheng Park in Ji’nan City. Additional specimens examined: CHINA. Shandong Province: Ji’nan City, Quancheng Park, on the trunk of Salix babylonica, elev. 47 m, 4 September 2022, P. M. Wang 219 B (EFHAAU 10567! [GenBank accession numbers — ITS: PP 576324, LSU: PP 576336]; same location, 4 September 2022, P. M. Wang 219 C (EFHAAU 10568!) and P. M. Wang 219 D (EFHAAU 10569!). Remarks: — It differs from the other similar species by its small-sized basidiomata on the trunk of Salix babylonica, yellowish pileus with a center pale ochre-yellow, and relatively small basidiospores.	en	Wang, Pan-Meng, Li, Zhuang, Wei, Yong-Qi, Huang, Zhi-Bo, Tian, Wen-Jie, Shen, Jing-Xu, Han, Dong-Fang, Shao, Xiao-Na (2024): A new agaricoid species of Porotheleum (Porotheleaceae, Agaricales) from Shandong Province, China. Phytotaxa 670 (1): 55-62, DOI: 10.11646/phytotaxa.670.1.5, URL: https://doi.org/10.11646/phytotaxa.670.1.5
