Cyanosporus miscanthi Y. C. Dai, Chao G. Wang, Yuan Yuan & Ghobad-Nejhad sp. nov.

Figs 4, 5

Holotype.

China. • Xizang Autonomous Region: Nyingchi, Medog County, 24 Oct. 2023, on dead Miscanthus, Dai 26687 (BJFC 044237, GenBank: ITS PP 479786, LSU PP 479808, mtSSU PP 510201, nrSSU PP 488293, RPB 1 PP 526263, RPB 2 PP 526272, TEF 1 PP 526277).

Etymology.

In reference to Miscanthus the genus where this species was found.

Diagnosis.

Cyanosporus miscanthi is characterized by effused-reflexed to pileate tiny basidiomata, slightly concentrically zonate pileal surface, white to pale bluish gray pore surface when fresh, angular pores, 7–9 per mm, fusoid cystidioles and cylindrical to allantoid basidiospores, 4–5 × 1.5–2 µm.

Basidiomata annual, effused-reflexed to pileate, soft and without odor or taste when fresh, becoming fragile to soft corky upon drying, up to 1 cm long and 0.8 cm wide when resupinate; pileus semicircular, projecting up to 0.8 cm, 1.2 cm wide and 1.2 mm thick at the base. Pileal surface white, pale bluish gray to bluish green when fresh and dry, velutinate, slightly concentrically zonate when dry; margin sharp, slightly curved when dry. Hymenophore poroid, white to pale bluish gray when fresh, becoming bluish gray to ash gray when dry; sterile margin almost absent; pores angular, 7–9 per mm; dissepiments thin, entire to slightly lacerate. Context white, soft corky, up to 0.3 mm thick. Tubes concolorous with pore surface, fragile to soft corky when dry, up to 0.9 mm long. Context and tubes turn dark olive green in KOH.

Hyphal system monomitic; hyphae clamped, hyaline, slightly thick-walled, smooth, with a wide lumen, frequently branched, more or less flexuous, in the context loosely interwoven, 3–4.5 µm in diam in the tubes subparallel along the tubes, agglutinated, 2.5–3 µm in diam.

Cystidia absent, but cystidioles fusoid present, thin-walled, 11–15 × 4 µm.

Basidia clavate, 9–13 × 4–5 µm, with four sterigmata and a basal clamp connection.

Basidiospores cylindrical to allantoid, 4–5 (– 5.5) × 1.5–2 µm, L = 4.2 µm, W = 1.9 µm, Q = 2.2–2.4 (n = 120 / 4), hyaline, thin-walled, IKI -, CB -.

Type of rot.

Brown rot.

Additional specimens examined.

China. • Xizang Autonomous Region: Nyingchi, Medog County, 24 Oct. 2023, on dead Miscanthus, Dai 26684 (BJFC 044234, ITS PP 479784, LSU PP 479806, mtSSU PP 510199, nrSSU PP 488291, RPB 1 PP 526261, RPB 2 PP 526270, TEF 1 PP 526276); Dai 26695 (BJFC 044245, ITS PP 479787, LSU PP 479809, mtSSU PP 510202, nrSSU PP 488294, RPB 1 PP 526264, RPB 2 PP 526273, TEF 1 PP 526278); Dai 26689 (BJFC 044239, ITS PP 479783, LSU PP 479805, mtSSU PP 510198, nrSSU PP 488290, RPB 1 PP 526260, RPB 2 PP 526269, TEF 1 PP 526275); Dai 26701 (BJFC 044251, ITS PP 479785, LSU PP 479807, mtSSU PP 510200, nrSSU PP 488292, RPB 1 PP 526262, RPB 2 PP 526271).