A contribution to the genus Steccherinum (Steccherinaceae, Polyporales): Introducing two new species and two new combinations of the genus

Abstract

Two new wood-inhabiting fungi from China,Steccherinum juniperiandS. incrustans, in the family Steccherinaceae are described and illustrated based on morphological and molecular analyses. The speciesS. juniperiwas found growing on the rotten wood ofJuniperusin Qinghai Province, China, whileS. incrustanswas collected on rotten angiosperm wood in Yunnan Province, China. The characteristics ofS. juniperiinclude annual, resupinate basidiomata with a buff yellow fresh pore surface that becomes apricot orange when bruised, angular pores of 3–6 per mm, subicular generative hyphae sometimes covered with crystals, the presence of encrusted skeletocystidia in tube trama only, fusiform to slim clavate cystidioles, and ellipsoid basidiospores measuring as 3–4 × 2–3 μm. The characteristics ofS. incrustansinclude annual, resupinate basidiomata with a buff yellow or pinkish buff to clay buff dried pore surface, angular pores (8–10 per mm), generative hyphae in trama frequently covered with crystals, the presence of encrusted skeletocystidia in tube trama and hymenium, and ellipsoid basidiospores (3.5–4.5 × 2.5–3.5 μm). Phylogenetic analysis based on a combined 2-locus dataset [ITS1-5.8S-ITS2 (ITS) + nuclear large subunit RNA (nLSU)] shows that the two species are members ofSteccherinum, and they are compared with morphologically similar and related species of this genus, respectively. In addition, two new combinations fromJunghuhnia, transferred toSteccherinumasS. austrosinenseandS. nandinae, are proposed based on examination of their type materials and phylogenetic analysis.