Cyanosporus rigidus B.K. Cui & Shun Liu, 2022

Liu, Shun, Xu, Tai-Min, Song, Chang-Ge, Wu, Chang-Lin ZhaoDong-Mei & Cui, Bao-Kai, 2022, Species diversity, molecular phylogeny and ecological habits of Cyanosporus (Polyporales, Basidiomycota) with an emphasis on Chinese collections, MycoKeys 86, pp. 19-46 : 19

Cyanosporus rigidus B.K. Cui & Shun Liu sp. nov.

Figs 6 , 7

Diagnosis.

Cyanosporus rigidus is characterised by corky, hard corky to rigid basidiomata with a buff yellow to clay-buff and tomentose pileal surface when fresh, becoming olivaceous buff to greyish brown when dry, smaller and cylindrical to allantoid basidiospores (3.7-4.2 × 0.9-1.3 μm).

Holotype.

China. Yunnan Province, Yulong County, Laojun Mountain, Jiushijiu Longtan, on fallen trunk of Abies sp., 15.IX.2018, Cui 17032 ( BJFC 030331).

Etymology.

Rigidus (Lat.): referring to the rigid basidiomata.

Fruiting body.

Basidiomata annual, pileate, corky, without odour or taste when fresh, becoming hard corky to rigid upon drying. Pileus flabelliform, projecting up to 1.6 cm, 3.8 cm wide and 0.6 cm thick at base. Pileal surface tomentose, buff yellow to clay-buff, when fresh, becoming smooth, rugose, olivaceous buff to greyish brown when dry; margin obtuse. Pore surface white to cream when fresh, becoming buff-yellow to pinkish buff when dry; sterile margin narrow to almost lacking; pores angular, 5-8 per mm; dissepiments thin, entire to lacerate. Context cream to buff, hard corky, up to 4 mm thick. Tubes cream to pinkish buff, brittle, up to 5 mm long.

Hyphal structure.

Hyphal system monomitic; generative hyphae with clamp connections, IKI-, CB-; hyphae unchanged in KOH.

Context.

Generative hyphae hyaline, thin- to slightly thick-walled with a wide lumen, rarely branched, loosely interwoven, 2.2-5 μm in diam.

Tubes.

Generative hyphae hyaline, thin- to slightly thick-walled with a wide lumen, occasionally branched, interwoven, 2-4 μm in diam. Cystidia and cystidioles absent. Basidia clavate, bearing four sterigmata and a basal clamp connection, 12.4-14.8 × 3-4.2 μm; basidioles dominant, in shape similar to basidia, but smaller, 11.8-13.9 × 2.6-4 μm.

Spores.

Basidiospores allantoid to cylindrical, slightly curved, hyaline, thin- to slightly thick-walled, smooth, IKI-, CB-, (3.5-)3.7-4.2 × (0.8-)0.9-1.3(-1.4) μm, L = 3.94 μm, W = 1.09 μm, Q = 3.66 (n = 60/1).

Type of rot.

Brown rot.

Figures

Figure 6. Basidiomata of Cyanosporus rigidus (Holotype, Cui 17032). Scale bar: 1.5 cm. The upper figure is the upper surface and the lower figure is the lower surface of the basidiomata.

Figure 7. Microscopic structures of Cyanosporus rigidus (Holotype, Cui 17032) a basidiospores b basidia and basidioles c hyphae from trama d hyphae from context. Drawings by: Shun Liu.