Coltricia hainanensis Xin Zhang, G.Y. Zeng & Y.C. Dai, 2025

Zeng, Guang-Yu, Wu, Ying-Da, Zhu, An-Hong & Zhang, Xin, 2025, A new species and a new combination of Coltricia (Hymenochaetaceae, Basidiomycota) from China, Phytotaxa 702 (3), pp. 274-286 : 277-279

Coltricia hainanensis Xin Zhang, G.Y. Zeng & Y.C. Dai , sp. nov. Figs. 2 , 3 .

MycoBank: MB857639

Etymology: — Hainanensis , refers to the species being found in Hainan Province, South China.

Diagnosis: — Coltricia hainanensis differs from other Coltricia species by the combination of centrally stipitate basidiomata, concentrically zonate, velutinate pileal surface becoming snuff brown to date brown when dry, thick-walled, oblong-ellipsoid to mango-shaped basidiospores with a distinctive large guttule (7.3–11 × 4–5.2 µm) and growth on soil in angiosperm forests.

Holotype: — CHINA. Hainan Province, Baisha County, Qingsong , 19.114163°N, 109.263314°E, altitude 433 m, on ground in an angiosperm forest, 27 September 2024, Dai 30395 ( BJFC050654 ).

Description: —Basidiomata annual, centrally stipitate, solitary or a few fused, soft fibrous and without distinctive odor or taste when fresh, becoming fragile to soft corky when dry. Pilei more or less circular, up to 2.6 cm in diam, and 2.3 mm thick at center. Pileal surface fawn to brown when fresh, become snuff brown to date brown when dry, velutinate, concentrically zonate; margin thin, acute, white, sterile, slightly curving down upon drying. Pore surface honey to isabelline; pores angular, 1–2 per mm; dissepiments thin, slightly lacerate. Context umber, up to 1.8 mm thick. Tubes clay buff, up to 0.5 mm long. Stipe hazel, corky when dry, finely velutinate, up to 3.1 cm long, 3.5 mm in diam., more or less uniform with a swollen tip.

Hyphal system monomitic, generative hyphae simple septate, IKI–, CB–; tissue darkening but otherwise unchanged in KOH. Contextual hyphae yellowish, slightly thick-walled with a wide lumen, occasionally branched, frequently simple-septate, slightly straight, loosely interwoven, 4–7 µm in diam; hyphae in stipe similar to context, parallel along the stipe, rarely branched, 4.8–7.5 µm in diam. Tramal hyphae cinnamon-buff to yellowish brown, slightly thick-walled with a wide lumen, occasionally branched, frequently simple-septate, slightly straight, loosely interwoven, 4–6 µm in diam. Cystidia and cystidioles absent; basidia more or less broadly clavate, thin-walled, with four sterigmata and a basal simple septum, 16.8–20.5× 4.5–6.3 µm, basidioles in shape similar to basidia, but smaller. Basidiospores oblong-ellipsoid to mango-shaped, tapering at the apex, yellowish, thick-walled, finely verrucose, often with a large guttule, IKI–, CB–, (7–)7.3–11(–11.3) × (3.8–)4–5.2(–5.4) µm, L=8.25 µm, W=4.46 µm, Q=1.8–2.1 (n=60/2).

Additional specimen examined: — CHINA. Hainan Province, Baisha County, Qingsong, 19.128097°N, 109.268824°E, altitude 320 m, on ground in angiosperm forest, 27 September 2024, Dai 30394 (BJFC050653).

Figures

FIGURE 2. Basidiomata of Coltricia hainanensis (Dai 30395, holotype). Bar=2 cm.

FIGURE 3. Microscopic structures of Coltricia hainanensis (Dai 30395, holotype). (a) Basidiospores; (b) Basidia; (c) Basidioles; (d) Hyphae from trama; (e) Hyphae from context. Bars: a–e=10 µm.