Pseudolagarobasidium baiyunshanense M.L. Han, L.S. Bian & Q. An, 2021

Han, Mei-Ling, Bian, Lu-Sen, Zhang, Yu-Xin, Zhu, Ming-Cui & An, Qi, 2021, Pseudolagarobasidium baiyunshanense sp. nov. from China inferred from morphological and sequence analyses, Phytotaxa 483 (2), pp. 169-176 : 171-173

Pseudolagarobasidium baiyunshanense M.L. Han, L.S. Bian & Q. An , sp. nov. ( Figs. 2–3 )

MycoBank no.: 838548

Pseudolagarobasidium baiyunshanense is characterized by subcretaceous, odontioid to raduloid, white, grayish violet when fresh, cream, olivaceous buff when dry basidioma (at first deep olive in KOH then fading), short aculei (up to 1.8 mm long), monomitic hyphal system with clamped generative hyphae, ellipsoid to broadly ellipsoid basidiospores (4–6.1 × 2.9–3.9 µm).

Type.— China. Guangdong Province. Guangzhou, Baiyunshan national scenic area, on angiosperm stump, 8 June 2019, Han 405/ LFNC 000405 (holotype, LFNC!) .

Etymology.— baiyunshanense (Lat.) refers to the locality (baiyunshan) of the type specimen.

Basidioma. —Basidioma widely effuse, adnate, up to 50 cm long, 20 cm wide, 0.8-2.2 mm thick, subcretaceous, odontioid to raduloid with distinct, smooth, subcretaceous or felty areas between aculei, white (60), fawn (5), grayish violet (44) when fresh, cream (21), olivaceous buff (16) when dry, easily separable from the substratum, at first deep olive in KOH then fading; cracks scattered, unconspicuous or numerous, revealing cream context; context cream (21), subcretaceous; hymenial surface composed of brittle, fragile, subcretaceous aculei, 3-4 aculei per mm, sometimes 5 or 6 per mm, up to 1.8 mm long, terete to conical, single or fused at base, solid or hollow, penicillate to pubescent, occasionally with tiny warts or knobs along aculei surface; apices cream (21) or concolorous with base of aculeus, color deeper after touching; margin gradually thinning out, obtuse or subacute, adnate, with fibrillose or fimbriate edges.

Hyphal structure.— Hyphal system monomitic with clamped generative hyphae, IKI–, CB+. Aculei generative hyphae thin- to thick-walled, occasionally branched, 1.7–3.5 µm in diam. Subiculum often abundant with particles, generative hyphae thin- to thick-walled, occasionally branched, 2–3.5 µm in diam.

Cystidia. —Cystidia of two types: (a) tramal cystidia originating in aculei trama, subiculum, or subhymenium, cylindrical, clavate, thin-walled, clamped at base, 23–48 × 2.1–2.9 µm; (b) hymenial cystidia originating in hymenium, fusoid, subfusiform, thin-walled, clamped at base, 9–17 × 1.8–2.6 µm; basidia clavate, with four sterigmata and a basal clamp, 11.7–24.7 × 2.5–6.2 µm.

Spores.— Basidiospores ellipsoid to broadly ellipsoid, thin-walled, smooth, IKI–, CB+, 4–6.1(–6.3) × (2.8–)2.9– 3.9(–4.1) µm, L = 4.92 µm, W = 3.19 µm, Q = 1.53–1.56 (n = 60/2).

Additional specimens examined.— China. Guangdong Province. Guangzhou, Baiyunshan national scenic area, on living angiosperm tree, 8 June 2019, Han 406/ LFNC 000406 (paratype, LFNC!) .

Figures

FIGURE 2. Basidiomata of Pseudolagarobasidium baiyunshanense (A–B: fresh specimens; C–D: dry specimens; A, C: Han 405; B, D: Han 406). Scale bar: A = 3 cm; B = 4 cm; C–D = 1 cm.

FIGURE 3. Microscopic structures of Pseudolagarobasidium baiyunshanense (Han 405). A–B. Aculei section; C. Hyphae from aculei; D. Hymenial cystidia; E. Basidiospores; F. Tramal cystidia. Scale bars: A–F = 10 µm.