Conferticium subtropicum S.H. He & S.L. Liu, sp. nov.

MycoBank number: MB; Index Fungorum number: IF; Facesoffungi Number: FoF 10786;

Description

Sexual state: Fruiting body – Basidiomata annual, resupinate, effused, closely adnate, inseparable from substrate, coriaceous to crustose, up to 40 cm long, 6 cm wide, 100–200 µm thick. Hymenophore smooth to slightly tuberculate with scattered small tubercles, greyish orange [6B(3–6)], brownish orange [6C(4–8)] to light brown [6D(4–8)], immediately turning black in KOH, uncracked or densely cracked with age; margin thinning out, indistinct, usually indeterminate, concolorous with hymenophore.

Microscopic structuresHyphal system monomitic; all hyphae without clamps. Subiculum indistinct; subhymenium thickening, with a compact texture; generative hyphae colorless, thin-walled, smooth, interwoven, moderately branched and septate, 2–4 µm in diam. Cystidia (skeletocystidia) numerous, hyphoid, colorless to pale yellow, distinctly thick-walled, with a narrow lumen often enlarged at apex, smooth, dextrinoid, cyanophilous, vertically arranged, 5–6 µm in diam. Basidia clavate, colorless, thin- to thick-walled, smooth, repetitive, often projecting beyond the hymenium, with one to several constrictions, with four sterigmata and a basal simple septum, 35–55 × 4–6 µm; basidioles dominant, in shape similar to basidia, but slightly smaller. Basidiospores ellipsoid, colorless, thin-walled, smooth, amyloid, acyanophilous, (4–) 4.5–5 × 2.5–3 µm, L = 4.7 µm, W = 2.7 µm, Q = 1.7 (n = 40/2).

Asexual state: not observed.

Material examined: CHINA, Hunan Province, Dong’an County, Shunhuangshan Nature Reserve, on fallen angiosperm branch, 13 July 2015, He 2387 (BJFC 020841); Jiangxi Province, Lianping County, Jiulianshan Nature Reserve, on fallen angiosperm trunk, 14 August 2016, He 4373 (BJFC 023814); Yunnan Province, Lushui County, Gaoligongshan Nature Reserve, on fallen angiosperm trunk, 28 November 2015, He 3317 (BJFC 021712); Binchuan County, Jizhushan Nature Reserve, on stump of Quercus, 30 August 2015, He 2814 (BJFC 026769) & He 2833 (BJFC 026770); Zhejiang Province, Kaihua County, Gutianshan Nature Reserve, on fallen angiosperm trunk, 12 August 2013, He 1804 (BJFC 016271); 13 August 2013, He 1827 (BJFC 016294, holotype, isotype in BJM).

Distribution: China

Sequence data: ITS: KY860405 (ITS5/ITS4); LSU: KY860463 (LROR/LR7)

Notes: Conferticium subtropicum is characterized by yellow to brown basidiomata, numerous skeletocystidia and smooth basidiospores. In the phylogenetic tree, C. subtropicum formed a strongly supported lineage sister to C. ochraceum, the type species of the genus. Morphologically, C. ochraceum differs from C. subtropicum by having typical gloeocystidia, not projecting basidia and a distribution in temperate areas mainly on gymnosperm trees (Wu 1996).

Fig. 6. Conferticium subtropicum (BJFC 016294, holotype). a Basidiomata. b Basidiospores. c Basidia. d Basidioles. e Skeletocystidia. f Generative hyphae. Scale bars: a = 1 cm, b–f = 10 μm.