Phanerochaete canobrunnea Sheng H. Wu, C.C. Chen & C.L. Wei

Wu, Sheng-Hua, Chen, Che-Chih & Wei, Chia-Ling, 2018, Three new species of Phanerochaete (Polyporales, Basidiomycota), MycoKeys 41, pp. 91-106 : 91

Phanerochaete canobrunnea Sheng H. Wu, C.C. Chen & C.L. Wei sp. nov. Figs 3A, 4

Diagnosis.

Phanerochaete canobrunnea is recognised by brown generative hyphae and brown skeletal hyphae, in combination with absence of cystidia.

Holotype.

TAIWAN. Nantou County: Yuchih Township, Lienhuachih, 23°55'N, 120°53'E, 715 m alt., on angiosperm branch, coll. W.C. Chen, C.C. Chen & C.L. Wei, 23 Jun 2015, CHWC 1506-17 (TNM F0029207).

Etymology.

From canus+brunneus (= greyish-brown), referring to the colour of the hymenial surface.

Description.

Basidiome resupinate, effuse, loosely adnate, membranaceous, 250-500 μm thick in section. Hymenial surface pale greyish-brown, slightly darkening in KOH, smooth, sometimes cracked; margin concolorous or brownish, slightly fibrillose or determinate.

Hyphal system dimitic; generative hyphae mostly simple-septate, single or double clamp connections occasionally present in subiculum. Subiculum fairly uniform, with fairly loose texture, 200-400 μm thick; generative hyphae interwoven, brown, more or less straight, moderately ramified, rarely encrusted, 4-9 (-11) μm diam., thin- to thick-walled, walls up to 1.5 μm thick, anastomoses occasional; skeletal hyphae interwoven, brown, more or less straight, un-ramified or ramified, 2-5 μm diam., usually subsolid or thick-walled, walls up to 1.5 μm, adventitious septa occasionally present. Hymenial layer thickening, with dense texture, 50-100 μm thick; hyphae more or less vertical, brownish to subcolourless, 3-6 μm diam., thin-walled. Cystidia lacking. Basidia subclavate to clavate, 15-25 × 5-6 μm, 4-sterigmate. Basidiospores ellipsoid to narrowly ellipsoid, adaxially flattened, smooth, thin-walled, IKI -, CB -, mostly 4.2-5.8 × 2.5-3 μm. [(4-) 4.5-5.8 (-6) × (2.5-) 2.7-3 (-3.2) μm, L = 5.10 ± 0.54 μm, W = 2.86 ± 0.18 μm, Q = 1.78 (n = 30) (CHWC 1506-17); (4-) 4.2-5 (-5.8) × (2.3-) 2.5-2.8 (-3) μm, L = 4.63 ± 0.42 μm, W = 2.66 ± 0.17 μm, Q = 1.75 (n = 30) (CHWC 1506-39)].

Additional specimens examined (paratypes).

TAIWAN. Nantou County: Yuchih Township, Lienhuachih, 23°55'N, 120°53'E, 715 m alt., on angiosperm branch, coll. W.C. Chen, C.C. Chen & C.L. Wei, 23 Jun 2015, CHWC 1506-39 (TNM F0029217); CHWC 1506-66 (TNM F0029236).

Distribution.

Known from subtropical Taiwan.

Remarks. Amongst the few species in Phanerochaete having brown subicular hyphae, only P. canobrunnea and P. thailandica possess skeletal hyphae [described as "quasi-binding hyphae" in the protologue of P. thailandica , Sadlikova and Kout (2017)]. These two species are also closely related according to the phylogenetic analyses (Fig. 2). However, P. thailandica bears leptocystidia and has larger basidiospores (7-8 × 4-4.5 µm) ( Sadlikova and Kout 2017). Phanerochaete brunnea Sheng H. Wu resembles P. canobrunnea in lacking cystidia and having similar basidiospores, but its hyphal system is monomitic ( Wu 1990). These two species are phylogenetically not closely related (Fig. 2).