MycoBank no.: MB 820386

Diagnosis.—Differs from other Dentipellis species by gloeocystidia presenting in hymenium, and minutely rough, oblong-ellipsoid basidiospores measured as 5–5.5 × 2.5–3.2 μm.

Type.— CHINA. Yunnan Province, Mengla County, Wangtianshu Nat. Res., alt. 1350 m, on fallen angiosperm trunk, 2 Nov. 2009, Cui 8545 (holotype, BJFC!)

Etymology.— Tropicalis (Lat.), referring to the distribution in tropical regions.

Basidiomata. —Annual, resupinate, easily separated from substratum, without odor or taste when fresh, fragile upon drying, up to 12 cm long, 6 cm wide, 2 mm thick at center. Fresh spines soft, white to cream, becoming fragile, cream to buff when dry, up to 1.5 mm long, 4–5 per mm across base. Margin cottony, buff to clay-buff, up to 4 mm wide. Subiculum thin, soft corky, buff, up to 1 mm thick.

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

Subiculum.— Generative hyphae hyaline, thin- to thick-walled, frequently branched, interwoven, 1.5–4 μm in diam. Gloeoplerous hyphae absent.

Hymenophoral trama. —Generative hyphae hyaline, thin- to thick-walled, occasionally branched, 2.5–3 μm in diam.

Hymenium. —Gloeocystidia present, tubular, hyaline, thin-walled, 2–6 μm in diam, up to 150 μm long; basidia clavate, with four sterigmata and a basal clamp connection, 16–20 × 3.5–6 μm; basidioles similar to basidia in shape, but smaller. Basidiospores oblong ellipsoid, thick-walled, hyaline, minutely rough, strongly amyloid, CB+, (4.6–)5– 5.5 × 2.5–3.2(–3.5) μm, L = 5.21 μm, W = 3.09 μm, Q = 1.55–1.72 (n = 60/2).

Additional specimen examined (paratype).— CHINA. Yunnan Province, Mengla County, Wangtianshu Nat. Res., alt. 1350 m, on fallen angiosperm trunk, 19 Oct. 2013, He 1993 (BJFC!).