Two new wood-rotting fungi in the family Hymenochaetaceae, Fulvifomes dracaenicolasp. nov. and Hymenochaete dracaenicolasp. nov., are described and illustrated from tropical China based on morphological characteristics and molecular data. It is worth to mention that both of them grow on Dracaena cambodiana which is a kind of angiosperm tree distributed in tropical regions. F. dracaenicola is characterised by perennial, pileate, triquetrous basidioma with yellowish brown fresh pores which becoming honey yellow with silk sheening upon drying, a dimitic hyphal system in trama and monomitic in context, and subglobose basidiospores measuring 4.8–5 × 4–4.1 μm. H. dracaenicola is characterised by annual, resupinate basidioma with a clay buff hymenophore, a dimitic hyphal system, absence of tomentum and cortex, presence of subulate setae, absence of cystidia, presence of cystidioles and simple hyphidia, and oblong ellipsoid basidiospores measuring 5.2–5.8 × 2.5–2.8 µm. The phylogenetic analyses based on ITS + nLSU rDNA sequences confirm the placement of two new species respectively in Fulvifomes and Hymenochaete. Phylogenetically closely related species to the two new species are discussed.

Species in Ceriporia and Meripilus are important wood-decaying fungi causing white rot on both angiosperm and gymnosperm wood. Morphologically, the two genera share similar micromorphology: a monomitic hyphal system of cyanophilous generative hyphae bearing simple septa. Phylogenetic and morphological analyses of Ceriporia and other related genera in Irpicaceae and Meripilus in Meripilaceae were carried out. Ceriporia is characterized by mostly resupinate basidiomata with a white to brightly colored pore surface when fresh, usually without changing color when bruised, and cylindrical to allantoid basidiospores. Meripilus is similar to Ceriporia, but it has resupinate, effused-reflexed to pileate basidiomata, sometimes with an erubescent pore surface when bruised, and ellipsoid to globose basidiospores. Phylogenies of species in the two genera were reconstructed with multiple-loci DNA sequences, including ITS, nLSU, nSSU, TEF1, RPB1, and RPB2, as well as two combined datasets: ITS+nLSU+TEF1+RPB1+nSSU for Ceriporia and ITS+nLSU+TEF1+RPB2+nSSU for Meripilus. Three new species of Ceriporia, one new species of Meruliopsis, and six new species of Meripilus are described and illustrated. Moreover, the evolutionary times of the Polyporales, including Irpicaceae and Meripilaceae, were revealed based on the conserved regions of three-loci DNA sequences (ITS+nLSU+TEF1). Irpicaceae and Meripilaceae are estimated to have emerged at the junction of the early and late Cretaceous, with mean crown ages of 108.9 Myr and 97.23 Myr, respectively. Bayesian evolutionary analysis shows that the divergence of Ceriporia emerged with a mean crown age of 83.61 Myr [95% highest posterior density (HPD): 65.25–106.35 Myr], which occurred during the late Cretaceous; the initial diversification of Meripilus also occurred during the late Cretaceous, with a mean crown age of 81.38 Myr [95% HPD: 61.89–105.78 Myr].

Brown-rot fungi are types of fungi that selectively degrade cellulose and hemicellulose from wood and are perhaps the most important agents involved in the degradation of wood products and dead wood in forest ecosystem. Two new brown-rot species, collected from southern China, are nested within the clades of Fomitopsis sensu stricto and Oligoporus sensu stricto, respectively. Their positions are strongly supported in the Maximum Likelihood phylogenetic tree of the concatenated the internal transcribed spacer (ITS) regions, the large subunit of nuclear ribosomal RNA gene (nLSU), the small subunit of nuclear ribosomal RNA gene (nuSSU), the small subunit of mitochondrial rRNA gene (mtSSU), the largest subunit of RNA polymerase II (RPB1), the second largest subunit of RNA polymerase II (RPB2) and the translation elongation factor 1-α gene (TEF1) sequences. Fomitopsis bambusae, only found on bamboo, is characterised by its resupinate to effused-reflexed or pileate basidiocarps, small pores (6–9 per mm), the absence of cystidia, short cylindrical to oblong-ellipsoid basidiospores measuring 4.2–6.1 × 2–2.3 μm. Oligoporus podocarpi is characterised by white to pale cream pore surface, round or sometimes angular pores (5–6 per mm), broadly ellipsoid to reniform basidiospores measuring 3.8–4.2 × 2–2.3 μm and growing on Podocarpus. Illustrated descriptions of these two novel species, Fomitopsis bambusae and Oligoporus podocarpi, are provided.

Megasporoporia sensu lato has recently been intensively studied in China and South America, and four independent clades representing four genera have been recognized phylogenetically. In this study, more samples, mostly from subtropical and tropical Asia, Oceania, and East Africa, are analyzed. A phylogeny based on a 4-gene dataset of sequences (ITS + nLSU + mtSSU + tef) has confirmed the presence of four genera in Megasporoporia sensu lato: Jorgewrightia, Mariorajchenbergia, Megasporia, and Megasporoporia sensu stricto. Six new species, Jorgewrightia austroasiana, Jorgewrightia irregularis, Jorgewrightia tenuis, Mariorajchenbergia subleucoplaca, Megasporia olivacea, and Megasporia sinuosa, are described based on morphology and phylogenetic analysis. Three new combinations are proposed, viz. Jorgewrightia kirkii, Mariorajchenbergia epitephra, and Mariorajchenbergia leucoplaca. To date, 36 species of Megasporoporia sensu lato are accepted and an identification key to these species is provided. In addition, the identification of Dichomitus amazonicus, Dichomitus cylindrosporus, and Megasporoporia hexagonoides is discussed.

The wood-inhabiting fungi refer to large basidiomycetes that grow on various woody materials and are distributed in various forest ecosystems, some of which have important economic value. In the present study, two new resupinate, adnate, wood-inhabiting fungal taxa, Botryobasidium latihyphum and B. zhejiangensis, are introduced based on morphological and molecular characteristics. A molecular phylogenetic study based on sequence data from the internal transcribed spacers (ITS) and the large subunit (nLSU) regions supported the two new species in the genus Botryobasidium. Maximum likelihood (ML), maximum parsimony (MP), and Bayesian inference (BIBI) were employed to perform phylogenetic analyses of these datasets. The new species B. latihyphum is characterized by its cream hymenial surface when fresh, olivaceous buff when dry, a monomitic hyphal system with clamp connections, the presence of clavate to tubular cystidia, basidia with six sterigmata, and broadly oval basidiospores measuring 7.9–10.2 × 3.2–4.3 μm. Botryobasidium zhejiangensis sp. nov. is characterized by its white to buff-yellow hymenial surface when fresh, cream when dry, a monomitic hyphal system with clamp connections, lacking cystidia, basidia with six sterigmata, and broadly navicular basidiospores measuring 7.9–9.2 × 2.6–3.4 μm. The phylogenetic result inferred from ITS + nLSU sequence data revealed that B. latihyphum is closely related to B. vagum, B. laeve, B. subincanum, and B. incanum, while B. zhejiangensis is closely related to B. leptocystidiatum, B. subcoronatum, B. xizangense, and B. intertextum.

Bark is vital for woody plants, providing protection, transporting nutrients and water, and storing essential resources. For fire-prone ecosystems, bark thickness is a key adaptive trait conferring fire resistance. Few studies have been conducted on the drivers of variation in bark thickness of the widely distributed Larix gmelinii (Rupr.) Kuzen in the Great Xing’an Mountains region, on the southern edge of East Siberia, where surface fire disturbances are frequent. To elucidate the relationships between variation in bark thickness (inner vs. outer bark) of L. gmelinii and plant size, environmental factors, and co-variation with other fire-tolerance traits, we selected 26 sites to set up plots and carried out a survey and bark sampling. Results showed that stem diameter primarily determines variation in bark thickness, especially outer bark. The proportion of outer bark to total bark increased accordingly as the tree increased in size. We also observed stronger correlated variation in outer bark thickness, tree height, and self-pruning capacity, implying that larger trees have thicker protective outer bark and taller heights with greater self-pruning, mitigating crown fire risks. Environmental factors appear to have a relatively limited effect on changes in bark thickness in L. gmelinii. Mean air temperature, annual precipitation, and total soil nitrogen content had some effect on outer bark thickness, and mean air temperature had some effect on inner bark thickness.