Four new corticioid species in Trechisporales (Basidiomycota) from East Asia and notes on phylogeny of the order

Morphological and molecular identification for four new wood-inhabiting species of Trechispora (Basidiomycota) from China

Four new wood-inhabiting fungi, Trechisporaalbofarinosa, T.bisterigmata, T.pileata and T.wenshanensisspp. nov., are proposed based on a combination of morphological features and molecular evidence. Trechisporaalbofarinosa is characterized by the farinose basidiomata with flocculence hymenial surface, a monomitic hyphal system with clamped generative hyphae, and ellipsoid, warted basidiospores. Trechisporabisterigmata is characterized by the membranous basidiomata with odontioid hymenial surface, rhizomorphic sterile margin, barrelled basidia and subglobose to broad ellipsoid, smooth basidiospores. Trechisporapileata is characterized by the laterally contracted base, solitary or imbricate basidiomata, fan shaped pileus, radially striate-covered surface with appressed scales, odontioid hymenophore surface, and subglobose to broad ellipsoid, thin-walled, smooth basidiospores. Trechisporawenshanensis is characterized by a cottony basidiomata with a smooth hymenial surface, and ellipsoid, thin-walled, warted basidiospores. Sequences of ITS and LSU marker of the studied samples were generated, and phylogenetic analyses were performed with the maximum likelihood, maximum parsimony, and Bayesian inference methods. The phylogenetic tree inferred from the ITS+nLSU sequences highlighted that four new species were grouped into the genus Trechispora.

A Molecular Systematics and Taxonomy Research on Trechispora (Hydnodontaceae, Trechisporales): Concentrating on Three New Trechispora Species from East Asia

Trechispora are an important genus of wood-inhabiting fungi that have the ability to decompose rotten wood in the forest ecosystem. In this study, we reported three new species of Trechispora: T. murina, T. odontioidea, T. olivacea from a subtropical region of Yunnan Province, China. Species descriptions were based on a combination of morphological features and phylogenetic analyses of the ITS and LSU region of nuclear ribosomal DNA. Trechispora murina is characterized by the resupinate basidiomata, grandinioid hymenial surface with a greyish tint, monomitic hyphal system and ellipsoid, thick-walled, ornamented basidiospores; T. odontioidea has an odontioid hymenial surface with cylindrical to conical, blunt aculei and subglobose to globose, colorless, slightly thick-walled, ornamented basidiospores; T. olivacea has a farinaceous hymenial surface with olivaceous tint, basidia clavate and thick-walled, ornamented, broadly ellipsoid to globose basidiospores. Sequences of the ITS and nLSU rDNA markers of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony, and Bayesian inference methods. After a series of phylogenetic analyses, the 5.8S+nLSU dataset was constructed to test the phylogenetic relationship of Trechispora with other genera of Hydnodontaceae. The ITS dataset was used to evaluate the phylogenetic relationship of the three new species with other species of Trechispora. Using ITS phylogeny, the new species T. murina was retrieved as a sister to T. bambusicola with moderate supports; T. odontioidea formed a single lineage and then grouped with T. fimbriata and T. nivea; while T. olivacea formed a monophyletic lineage with T. farinacea, T. hondurensis, and T. mollis.

Outline, Divergence Times, and Phylogenetic Analyses of Trechisporales (Agaricomycetes, Basidiomycota)

Phylogenetic analyses inferred from the nuc rDNA ITS1-5.8S-ITS2 (ITS) data set and the combined 2-locus data set [5.8S + nuc 28S rDNA (nLSU)] of taxa of Trechisporales around the world show that Sistotremastrum family forms a monophyletic lineage within Trechisporales. Bayesian evolutionary and divergence time analyses on two data sets of 5.8S and nLSU sequences indicate an ancient divergence of Sistotremastrum family from Hydnodontaceae during the Triassic period (224.25 Mya). Sistotremastrum family is characterized by resupinate and thin basidiomata, smooth, verruculose, or odontoid-semiporoid hymenophore, a monomitic hyphal structure, and generative hyphae bearing clamp connections, the presence of cystidia and hyphidia in some species, thin-walled, smooth, inamyloid, and acyanophilous basidiospores. In addition, four new species, namely, Trechispora dentata, Trechispora dimitiella, Trechispora fragilis, and Trechispora laevispora, are described and illustrated. In addition, three new combinations, namely, Brevicellicium daweishanense, Brevicellicium xanthum, and Sertulicium limonadense, are also proposed.

Two New Species of Fibrodontia (Trechisporales, Basidiomycota) with a Key to Worldwide Species

Fibrodontia is a genus of wood-inhabiting fungi consisting of four species so far, including F. gossypina as generic type. Two new species, Fibrodontia austrosinensis and F. subalba, are described and illustrated from China. Fibrodontia austrosinensis from southwestern China is characterized by a grandinioid to odontioid hymenophore with numerous small aculei, a dimitic hyphal system with scattered, smooth skeletal hyphae and ellipsoid basidiospores measuring 4.2–5.2 × 3.5–4.5 μm. Fibrodontia subalba from the West Tianshan Mountain in northwestern China is distinguished by an odontioid to hydnoid hymenophore, a dimitic hyphal system, and ellipsoid basidiospores measuring 3.7–4.4 × 2.8–3.4 μm. The phylogenies inferred from the data set of nuc rDNA ITS1-5.8S-ITS2 (ITS) and D1–D2 domains of nuc 28S rDNA (28S), and that of ITS, 28S, translation elongation factor (tef1α), and RNA polymerase II second largest subunit (rpb2) supported Fibrodontia as a monophyletic genus in the Trechisporales, and F. austrosinensis and F. subalba as separate lineages within Fibrodontia. Multi-rate Poisson Tree Processes, Automatic Barcode Gap Discovery and genetic distance methods based on ITS sequences of Fibrodontia also supported F. austrosinensis and F. subalba as distinct species. The taxonomic status of F. fimbriata that was recently transferred from Cystidiodendron, is briefly discussed. A key to all six known species of Fibrodontia is provided.

On Sistotremastrum and similar-looking taxa (Trechisporales, Basidiomycota)

The taxonomy of Sistotremastrum (Trechisporales, Basidiomycota) is revised based on morphology and DNA data. The genus is shown to be polyphyletic, and therefore it is split into two units—Sistotremastrum s. str. and Sertulicium, gen. nov. (typified with Corticium niveocremeum). Sistotremastrum s. str. is retained for eleven species of which eight are described as new while Sertulicium encompasses at least six species, including one new to science. Both of these genera are only distantly related to other representatives of the Trechisporales. Additionally, a new poroid neotropical species, Porpomyces abiens (Hydnodontaceae), is described as morphologically similar to some members of Sistotremastrum s. str.

The Phylogenetic Relationship Revealed Three New Wood-Inhabiting Fungal Species From Genus Trechispora

Wood-inhabiting fungi play a significant role in wood degradation and the cycle of matter in the ecological system. In the present study, three new wood-inhabiting fungal species, Trechispora bambusicola, Trechispora fimbriata, and Trechispora fissurata spp. nov., are nested in Trechispora, which are proposed based on a combination of morphological features and molecular evidence. Sequences of internal transcribed spacer (ITS) and large subunit (nLSU) regions of the studied samples were generated, and the phylogenetic analyses were performed with maximum likelihood, maximum parsimony, and Bayesian inference methods. The phylogenetic analyses inferred from ITS showed that T. bambusicola was sister to Trechispora stevensonii, T. fimbriata grouped with Trechispora nivea, and T. fissurata grouped with Trechispora echinospora. The phylogenetic tree based on ITS + nLSU sequences demonstrated that T. bambusicola formed a single lineage and then grouped with Trechispora rigida and T. stevensonii. T. fimbriata was sister to T. nivea. T. fissurata grouped with Trechispora thelephora.

Morphologically similar but not closely related: the long-spored species of Subulicystidium (Trechisporales, Basidiomycota)

Species boundaries and geographic distribution of corticioid fungi (resupinate Basidiomycota) are often poorly known. Our recent study on Subulicystidium showed that species diversity in this genus is at least twice as high as previously recognized. This re-estimation of the species diversity was based on a study of only a part of the genus. The present study sheds light on molecular and morphological diversity of three more species. We generated 27 ITS and 24 28S nuclear ribosomal DNA sequences from 49 specimens labelled as Subulicystidium cochleum, S. longisporum and S. perlongisporum and collected in distant geographic localities. We assessed pairwise dissimilarities and phylogenetic relationships of DNA sequences with Bayesian and maximum likelihood methods. We correlated phylogenetic information with morphological data on spores and cystidia. We found that the three species are not closely related, despite their similarity in spore shape and size. In one of the species, S. perlongisporum, we detected the presence of two sympatric lineages. These lineages are not morphologically distinct, except for a small difference in the mean length of cystidia. Our study provides a further example of transoceanic species distribution in Agaricomycetes.