AUTHOR=Dong Jun-Hong , Zhang Xun-Chi , Chen Jia-Jia , Zhu Zhong-Long , Zhao Chang-Lin 

TITLE=A phylogenetic and taxonomic study on Steccherinum (Polyporales, Basidiomycota): Focusing on three new Steccherinum species from southern China

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=12

YEAR=2023

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2022.1103579

DOI=10.3389/fcimb.2022.1103579

ISSN=2235-2988

ABSTRACT=<p>The wood-inhabiting fungi play an integral role in wood degradation and the cycle of matter in the ecological system. They are considered as the “key player” in wood decomposition, because of their ability to produce all kinds of enzymes that break down woody lignin, cellulose and hemicellulose. In the present study, three new wood-inhabiting fungal species, <italic>Steccherinum fissurutum</italic>, <italic>S. punctatum</italic> and <italic>S. subtropicum</italic> spp. nov., collected from southern China, are proposed based on a combination of morphological features and molecular evidence. <italic>Steccherinum fissurutum</italic> is characterized by the resupinate, subceraceous basidiomata with cracked hymenophore, a monomitic hyphal system with clamped generative hyphae and cylindrical basidiospores; <italic>S. punctatum</italic> is characterized by the annual, punctate basidiomata with leathery hymenophore, cylindrical, strongly encrusted cystidia and ellipsoid basidiospores (3.6–4.5 ×2.6–3.4 µm); <italic>S. subtropicum</italic> is characterized by its effuse-reflexed basidiomata, a odontioid hymenophore with pink to lilac hymenial surface and ellipsoid basidiospores measuring as (2.8–3.4 × 2.0–2.7 µm). Sequences of ITS and nLSU rRNA markers of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony, and Bayesian inference methods. The ITS+nLSU analysis of the family Steccherinaceae indicated that the three new species clustered into the genus <italic>Steccherinum</italic>. Based on further analysis of ITS+nLSU dataset, the phylogenetic analysis confirmed that <italic>S. subtropicum</italic> was sister to <italic>S</italic>. <italic>enuispinum</italic>; <italic>S</italic>. <italic>fissurutum</italic> formed a monophyletic lineage; <italic>S. punctatum</italic> grouped with a clade comprised <italic>S. straminellum</italic> and <italic>S. ciliolatum</italic>.</p>