Dentipellis fimbriata Sheng H. Wu & C.L. Wei, 2020

Wei, Chia-Ling, Chang, Chiung-Chih & Wu, Sheng-Hua, 2020, Dentipellis fimbriata sp. nov. (Russulales, Basidiomycota) from subtropical Taiwan, Phytotaxa 428 (2), pp. 131-138 : 136

Dentipellis fimbriata Sheng H. Wu & C.L. Wei , sp. nov. ( Figs. 2 , 3 )

Diagnosis. —This new species is diagnostic by resupinate basidiomes with rhizomorphic margins, having yellowish brown subicular hyphae, and bearing two kinds (tubular and fusoid-cylindrical) of gloeocystidia.

MycoBank no: 831394

Type. — TAIWAN. Pingtung County, Chunjih Township, 16 km of Tahanshan Forestry Road, 120°43’53.9”E, 22°24’55.2”N, 1000 m alt., on fallen angiosperm trunk, 12 June 2018, WEI 18-288 (Holotype, TNM F0032731).

Etymology.—From fimbriatus (L.), referring to the morphology of the basidiome margin.

Description. —Basidiomes resupinate, effuse, adnate, membranaceous, 250–500 μm thick in section (aculei excluded). Hymenial surface cream to buff, no color change in KOH, odontioid to hydnoid, minutely cracked when dry; margin whitish, with rhizomorphs. Aculei 3–4 per mm, subulate, separate, 0.4–1 mm long and 0.1–0.2 mm wide, apically slightly fimbriate.

Hyphal system monomitic; hyphae nodose-septate. Subiculum fairly uniform, with loose texture, with dense texture near substrate and hymenial layer, 220–450 μm thick; hyphae interwoven, ± vertical near hymenial layer, ± horizontal near substrate, yellowish brown near substrate, colorless near hymeanial layer, occasionally swollen or with small protuberance, richly ramified, 2–4 (–5) μm diam, with about 0.8–1 μm thick walls near substrate, thin- to slightly thick-walled elsewhere, finely encrusted near hymenial layer. Trama with dense texture; hyphae somewhat vertical, colorless, richly ramified, finely encrusted, 2–4 (–5) μm diam, thin- to slightly thick-walled. Hymenial layer slightly thickening, with dense texture, 30–50 μm thick; hyphae somewhat vertical, colorless, 2–3 μm diam, thin-walled. Gloeoplerous hyphae mainly present in trama, rare in subiculum, deeply stained by phloxine, 2–4 μm diam, thin- to slightly thick-walled. Gloeocystidia of two kinds: (1) tubular, originate from trama or subiculum, parallel with trama hyphae, usually curve into hymenium, immersed or slightly projecting, up to 250 μm long, 5–7 μm diam, thin-walled, SA–; (2) fusoid to cylindrical, originate from deep hymenial layer, slightly projecting, usually with narrow apices, occasionally moniliform toward apices, 30–65 × 6–9 μm diam, SA–. Basidia subclavate to clavate, 15–20 × 3.8–4 μm, 4-sterigmate. Basidiospores ellipsoid to broadly ellipsoid, asperulate, colorless, thin-walled, amyloid, acyanophilous, mostly 3–4 × 2.2–2.8 μm. (3–) 3.2–4 (–4.2) × (2.2–) 2.3–2.8 μm, L = 3.58±0.34 μm, W = 2.58±0.18 μm, Q = 1.39 (n = 30) (WEI 18-288).

Additional specimens (paratype) examined.— TAIWAN. Pingtung County, Chunjih Township, 16 km of Tahanshan Forestry Road, 120°43’53.9”E, 22°24’55.2”N, 1000 m alt., on fallen angiosperm trunk, 12 June 2018, WEI 18-305 (TNM F0032732).

Distribution and vegetation.—This new species is so far known only in southern subtropical Taiwan at 1000 m alt. The broad-leaved forest of the collecting site has many Fagaceae and Lauraceae spp.

Figures

FIGURE 2. Basidiomata of Dentipellis fimbriata (holotype, WEI 18-288). A. Basidiome margin with rhizomorphs; B. Odontioid to hydnoid hymenial surface. Bar = 1 mm.

FIGURE 3. Microscopic structures of Dentipellis fimbriata (holotype, WEI 18-288). A. Profile of basidiome section; B. Basidiome section; C. Basidiome section from trama; D. Gloeocystidia; E. Gloeocystidia; F. Basidia; G. Basidiospores (rightmost: in IKI). Bars: A = 100 μm; B–G = 10 μm.