Phylloporia minutipora and P. radiata spp. nov. (Hymenochaetales, Basidiomycota) from China and a key to worldwide species of Phylloporia

Abstract

Phylloporia is a monophyletic genus within the Hymenochaetaceae as recovered by nuclear large subunit ribosomal DNA (nLSU) sequences. According to the summarization of 38 species accepted in this genus, Phylloporia is characterized by an absence of setae and the presence of abundant thick-walled, colored and tiny basidiospores, although its other morphological characters are highly diverse. Nine herbarium specimens from China, fitting the morphological concept of Phylloporia, were morphologically and phylogenetically studied in detail. The phylogeny inferred from nLSU sequences shows that the nine specimens formed three terminal lineages within the Phylloporia clade. Two lineages being composed of four specimens from Hainan and three from Guizhou were newly described as Phylloporia minutipora and P. radiata, respectively. In Phylloporia, P. minutipora is distinct by a combination of annual, sessile and imbricate basidiocarps, distinctly concentrically sulcate pileal surface with obtuse margin, angular pores of 12–15 per mm, duplex context separated by a black zone, a dimitic hyphal system, and broadly ellipsoid basidiospores of 2.5–3 × 2–2.5 μm, while P. radiata is distinct by a combination of annual, sessile and imbricate basidiocarps, faintly sulcate and radially striate pileal surface, sharp pileal margin, angular pores of 8–10 per mm, duplex context separated by a black zone, a monomitic hyphal system, and broadly ellipsoid basidiospores of 2.5–3.5 × 2–2.5 μm. The third lineage, comprising two specimens from Hainan, was morphologically determined as Phylloporia pulla. This species was recently combined to Phylloporia based on only morphological characters, and the current study for the first time generated its molecular sequences for phylogenetic reference. A key to all 40 species of Phylloporia is provided.