Edible and medicinal mushrooms are extensively cultivated and commercially consumed around the world. However, green mold disease (causal agent, Trichoderma spp.) has resulted in severe crop losses on mushroom farms worldwide in recent years and has become an obstacle to the development of the Ganoderma industry in China. In this study, a new species and a new fungal pathogen on Ganoderma sichuanense fruitbodies were identified based on the morphological characteristics and phylogenetic analysis of two genes, the translation elongation factor 1-α (TEF1) and the second-largest subunit of RNA polymerase II (RPB2) genes. The new species, Trichoderma ganodermatigerum sp. nov., belongs to the Harzianum clade, and the new fungal pathogen was identified as Trichoderma koningiopsis. Furthermore, in order to better understand the interaction between Trichoderma and mushrooms, as well as the potential biocontrol value of pathogenic Trichoderma, we summarized the Trichoderma species and their mushroom hosts as best as possible, and the phylogenetic relationships within mushroom pathogenic Trichoderma species were discussed.

Lycogala is one of the most widely known genera of myxomycetes due to its distinct characteristics and cosmopolitan distribution. This study introduces a new species, Lycogala heterospora, based on its morphological characteristics and molecular analyses using the small subunit of the ribosomal RNA (nrSSU) gene. It is characterized by its spores of varying sizes and yellowish-brown peridial vesicles. The characteristics of the new species were examined under a stereomicroscope and a light microscope. The micrographs of relevant details are included. Moreover, Lindbladia cribrarioides is documented for the first time in China.

The genus Gymnopus plays a significant role in ecological systems, with certain species holding potential as food or medicinal resources. However, the species diversity of Gymnopus in China remains unclear. In recent years, more than one thousand Gymnopus specimens have been collected across China. Thus, through the integration of ecological evidence, detailed morphological studies, and phylogenetic analysis using a multiloci dataset of ITS + nLSU + tef1-ɑ, four new species—Gymnopus longistipes, Gymnopus striatipileatus, Gymnopus viridiscus, and Gymnopus spadiceus—have been differentiated from known species. Gymnopus similis has been newly documented from Jiangxi Province, China. Detailed descriptions and vivid illustrations have been provided based on the newly collected specimens, along with comparisons to closely related species. Additionally, a key to the reported species of Gymnopus s.l. from East China has been included.

The Calocybe species possess notable economic and medicinal value, demonstrating substantial potential for resource utilization. The taxonomic studies of Calocybe are lacking in quality and depth. Based on the specimens collected from northeast China, this study provides a detailed description of two newly discovered species, namely Calocybe betulicola and Calocybe cystidiosa, as well as two commonly found species, Calocybe decolorata and Calocybe ionides. Additionally, a previously unrecorded species, C. decolorata, has recently been discovered in Jilin Province, China. The two newly discovered species can be accurately distinguished from other species within the genus Calocybe based on their distinct morphological characteristics. The primary distinguishing features of C. betulicola include its grayish-purple pileus, grayish-brown to dark purple stipe, smaller basidiomata, absence of cellular pileipellis, and its habitat on leaf litter within birch forests. Calocybe cystidiosa is distinguished by its growth on the leaf litter of coniferous forests, a flesh-pink pileus, a fibrous stipe with a white tomentose covering at the base, non-cellular pileipellis, larger basidiospores, and the presence of cheilocystidia. The reconstruction of phylogenetic trees using combined ITS, nLSU, and tef1-α sequences, employing maximum likelihood and Bayesian inference analyses, showed that C. betulicola formed a cluster with C. decurrens, while C. cystidiosa clustered with C. vinacea. However, these two clusters formed separate branches themselves, which also supported the results obtained from our morphological studies. A key to the Calocybe species reported from northeast China is provided to facilitate future studies of the genus.

Hydnum, a well-defined genus in the family Hydnaceae (order Cantharellales), is characterized by its distinctive spine-bearing hymenophores. In this study, we performed a multi-locus phylogenetic analysis (ITS-nrLSU-tef1) of Hydnum species. Integrating morphological examinations and phylogenetic evidence, we identified and delineated five Hydnum species in China, which include four novel species (Hydnum crassipedum, H. albomarginatum, H. fulvostriatum, and H. bifurcatum) and the first record (H. orientalbidum) in Anhui Province. This study provides a comprehensive morphological description (including macroscopic morphology and microscopic structure), hand-drawn illustrations (encompassing basidiocarps, basidiospores, basidia, and pileipellis hyphae), morphological comparative analysis with similar species, and comparative phylogenetic analysis with related taxa. Furthermore, we developed a dichotomous key for identifying Hydnum species distributed in China.

Myxomycetes are an important component of terrestrial ecosystems, and in order to understand their diversity and phylogenetic relationships, taxonomic issues need to be addressed. In our 1985–2021 biodiversity investigations in Shaanxi Province, Jilin Province, the Inner Mongolia Autonomous Region, Hubei Province, and Henan Province, China, Diderma samples were observed on rotten leaves, rotten branches, and dead wood. The samples were studied, based on morphological features coupled with multigene phylogenetic analyses of nSSU, EF-1α, and COI sequence data, which revealed two new species (Diderma shaanxiense sp. nov. and D. clavatocolumellum sp. nov.) and two known species (D. radiatum and D. globosum). In addition, D. radiatum and D. globosum were newly recorded in Henan Province and the Inner Mongolia Autonomous Region, respectively. The paper includes comprehensive descriptions, detailed micrographs, and the outcomes of phylogenetic analyses for both the newly discovered and known species. Additionally, it offers morpho-logical comparisons between the new species and similar ones.