Molecular phylogeny and morphology reveal four new species in Hymenochaetales and one new species in Cantharellales from Southwestern China.

Abstract

Wood-decaying fungi represent a vital group of higher fungi that drive the cycling of matter and energy in forest ecosystems, and they have been the focus of thorough investigation. In this study, five new species, viz. Botryobasidiumdaweishanense, Inonotussubglobisporum, Kneiffiellabubalina, Xylodongranulanoides, and X.granulans from China, are described and illustrated based on the morphological characteristics and molecular phylogenetic analyses, in which the sequences of ITS+nLSU genes were used for the phylogenetic analyses by maximum likelihood and Bayesian inference methods. The phylogeny revealed that the Botryobasidiumdaweishanense groups with three taxa, viz., B.intertextum, B.leptocystidiatum, and B.subcoronatum. Inonotussubglobisporum is closely related to I.radiatus. Kneiffiellabubalina clustered sister to K.subalutacea. Xylodongranulanoides and X.granulans have a close relationship with X.bambusinus, X.fissuratus, X.subclavatus, X.montanus, and X.wenshanensis. Additionally, Xylodongranulanoides and X.granulans clustered together. Botryobasidiumdaweishanense is characterized by an araneose hymenial surface, fusiform, and cyanophilous basidiospores (6.1-7.3 × 3.3-3.9 μm). Inonotussubglobisporum is characterized by perennial basidiomata with lateral stipes, polygon pores measuring 4-6 per mm, and subglobose, cyanophilous basidiospores (3.6-4.3 × 2.8-3.5 μm). Kneiffiellabubalina is characterized by cream basidiomata and cylindrical to slightly allantoid basidiospores (8.0-8.9 × 1.8-2.3 μm). Xylodongranulanoides is characterized by grandinioid hymenial surfaces, various cystidia, and broadly ellipsoid, thick-walled basidiospores (4.7-5.3 × 3.6-4.1 μm). Xylodongranulans is characterized by grandinioid hymenial surfaces, capitate and clavate cystidia, and broadly ellipsoid basidiospores (3.8-4.2 × 2.9-3.3 μm). Phylogenetic analysis based on internal transcribed spacer (ITS) and nuclear large subunit RNA (nLSU) shows that the four species are members of Hymenochaetales, and one belongs to Cantharellales. All five new species are compared with morphologically and phylogenetically closely related species. The present study contributes to understanding the species diversity, taxonomy, and phylogeny of macrofungi in Southwestern China.