Xerula sinopudens R.H. Petersen et Nagasa
Basidiocarps small. Pileus 30-45 mm in diam, circular, applanate, depressed, brownish orange (5C3) at disc, brown (6E5) towards the margin, unpolished and dry, neither viscid nor gelatinized, covered with yellowish brown setae; context yellowish white, 4 mm thick at disc, fleshy. Lamellae broadly ventricose, adnexed, yellowish white (4A2), with 3-5 series of lamellulae, close to subdistant, breath 4-6mm. Stipe 70-90 mm long, 4-5 mm broad at apex, 7-8 mm broad at base, tapering upwards, central, fibrous, fistulose, pale yellow to brownish yellow; surface covered with yellowish brown setae; annulus absent; pseudorrhiza present.
Basidiospores 9.5-12 × 8-11 µm [n = 40, Lm = 10.68, Wm = 9.36, Q = (1.00) 1.05-1.25, Q = 1.14], subglobose to broadly ellipsoid, sometimes globose, smooth, colourless. Basidia (Fig. 6c) 40-65 × 13-28 µm, clavate to broadly clavate, 4-spored; thin-walled, without clamp connections; sterigmata 4-6 µm long. Pleurocystidia scattered, 80-135 × 23-35 µm, broadly fusiform, thin-walled, occasionally subcapitate, the apex without crystalline deposits, without basal clamp connections. Cheilocystidia scattered, similar to pleurocystidia. Pileocystidia 230-510 × 13-20 µm, erect, lanceolate with ventricose base and tapering tips, thick-walled (up to 8 µm), with dark brown cell wall; without clamp connections.
Habitat: On buried rotten wood in rain forests, solitary.
Specimens examined: THAILAND, Chiang Mai Prov., Doi Inthanon National Park, junction of Highway 1009 and road to Mae Chem, N19°31.58’ E 98°29.64’, elev. 1700 m, humid montane rainforest with Quercus, Castanopsis, Lithocarpus echinops etc. 20 June 2008, J.K. Liu 006 (MFU08 1325), 16 July 2008, J.K. Liu 035 (MFU08 1353)
Distribution: China; Indonesia; Japan; Papua New Guinea (Petersen & Nagasawa, 2006; Wang et al. 2008). New to Thailand.
Notes: Xerula sinopudens is similar to X. pudens, however, X. pudens differs from X. sinopudens by its common presence of clamp connections and much more thicker-walled (up to 6 µm) pleurocystidia. Wang et al. (2008) suggested that the presence or absence of clamp connections, the form and the thickness of the wall of pleurocystidia, and the size and the shape of basidiospores are important characters to distinguish the species within Xerula which was followed in this
study. (2009) demonstrated that the pileipellis of O. mucida is composed of coralloid terminal cells.
Fig. 1 Basidiocarp of Oudemansiella canarii; b-d. Basidiocarps of Oudemansiella aff. crassifolia; e-f: Basidiocarps of Oudemansiella submucida; g. Basidiocarp of Xerula sinopudens. Scale bars: a = 20 mm; b-d = 10 mm; e-f = 20 mm; g = 30 mm.
Fig. 2 Xerula sinopudens a: Pileipellis and pileocystidia; b: Spores; c: Basidia; d: Pleurocystidia. Scale bars: a= 60 µm; b = 10 µm; c = 20 µm; d = 40 µm.
Liu JK, Hyde KD, Zhao RL 2009 – Four species of Oudemansiella and Xerula newly recorded from Thailand. Cryptogamie, Mycologie 30: 341–353.