Morphology and multigene phylogeny revealed four new species of Xylodon (Schizoporaceae, Basidiomycota) from southern China

Abstract

Fungi are one of the most diverse groups of organisms on Earth, amongst which wood-inhabiting fungi play a crucial role in ecosystem processes and functions. Four new wood-inhabiting fungi, Xylodon cremeoparinaceus, X. luteodontioides, X. poroides and X. wumengshanensis are proposed, based on morphological features and molecular evidence. Xylodon cremeoparinaceus is distinguished by a cream hymenial surface with a pruinose hymenophore, a monomitic hyphal system with clamped generative hyphae and ellipsoid basidiospores. Xylodon luteodontioides is characterised by flavescens hymenophore surface with odontioid hymenophore, monomitic hyphal system with clamped generative hyphae and ellipsoid basidiospores. Xylodon poroides bears coriaceous basidiomata with a poroid hymenophore surface, monomitic hyphal system with clamped generative hyphae and ellipsoid basidiospores. Xylodon wumengshanensis is a distinct taxon by its grandinoid hymenophore surface, monomitic hyphal system with clamped generative hyphae and ellipsoid basidiospores. Sequences of ITS and nLSU rRNA markers of the studied samples were generated and phylogenetic analyses were performed using the Maximum Likelihood, Maximum Parsimony, and Bayesian Inference methods. The phylogram, based on the ITS+nLSU rDNA gene regions, included three genera within the Schizoporaceae as Fasciodontia, Lyomyces and Xylodon. The four new species were grouped into the genus Xylodon. The topology, based on the ITS sequences, revealed that Xylodon cremeoparinaceus was grouped closely with X. pruinosus, X. detriticus and X. ussuriensis. The taxon X. luteodontioides was sister to X. nesporii. The species X. poroides separated from X. pseudotropicus, while X. wumengshanensis was grouped with four taxa: X. patagonicus, X. radula, X. subtropicus and X. taiwanianus.