Postia duplicata L.L. Shen, B.K. Cui & Y.C. Dai, 2014

Postia duplicata L.L. Shen, B.K. Cui & Y.C. Dai View in CoL , sp. nov. ( Figs. 1–2 View FIGURE 1 View FIGURE 2 )

MycoBank no.: MB 808217

Differs from other Postia species by basidiomata with duplex context, color change after bruising, presence of gloeocystidia in the hymenium, and cylindrical basidiospores which are 3.8–5.8 × 1.8–2.5 µm.

Type.— CHINA. Zhejiang Prov.: Qingyun County, Baishanzu Nat. Res. , elev. 900 m, on rotten angiosperm wood, 14 August 2013, Dai 13411 (holotype, BJFC! ; isotype, IFP! ).

Etymology.— duplicata (Lat.) , referring to two layers of context in the species.

Basidiomata.—Basidiomata annual, pileate, solitary, soft corky and watery when fresh, without odor or taste, becoming corky and light in weight when dry. Pileus flabelliform, projecting up to 3.5 cm, 6 cm wide, 1.6 cm thick at the base. Pileal surface white to cream when fresh, glabrous, becoming cinnamon to reddish brown when bruised or upon drying. Pore surface white when fresh, pale brownish to brown when bruised, becoming reddish brown upon drying; pores irregular, 3–4 per mm; dissepiments thin, entire. Sterile margin narrow, brown, up to 1 mm wide. Context duplex, an irregular black line present, the upper layer soft, grey to olivaceous buff, up to 5.5 mm thick; the lower layer dense, cream to buff, up to 4.5 mm thick. Tubes pale brown, fragile when dry, up to 6 mm long.

Hyphal structure. —Hyphal system monomitic; generative hyphae with clamp connections, IKI–, CB–; tissue unchanged in KOH.

Context. —Generative hyphae hyaline, slightly thick-walled to thick-walled with a wide lumen, frequently branched, loosely interwoven, 4.0–7.0 µm in diam.

Tubes. —Generative hyphae hyaline, thin- to slightly thick-walled with a wide lumen, occasionally branched, interwoven, 2.0–4.0 µm in diam. Gloeocystidia present in the hymenium, hyphoid to narrowly clavate, thin-walled, 26.0–34.0 × 2.0–3.0 µm; cystidioles abundant, fusoid, thin-walled, 21.0–29.0 × 4.5–5.5 µm, basidia clavate, with four sterigmata and a basal clamp connection, 20.0–28.0 × 4.0–5.0 µm; basidioles dominant, in shape similar to basidia, but distinctly smaller.

Spores. —Basidiospores cylindrical, hyaline, thin-walled, smooth, IKI–, CB–, (3.6–)3.8–5.8 × 1.8–2.5(–2.6) µm, L = 4.65 µm, W = 2.05 µm, Q = 2.28–2.41 (n = 60/2).

Additional specimen examined.— Postia duplicata : CHINA. Yunnan Prov.: Lanping County, Tongdian, Luoguqing , elev. 1700m, on stump of Pinus , 19 September 2011, Cui 10366 (paratype, BJFC!) .