Armillaria korhonenii, designated as Chinese biological species Q (CBSQ) here, is described as a new species based on phylogenetic and morphological evidence as well as the results of mating tests. This species is the sixteenth biological species of Armillaria reported from China following the discovery of 15 previously known biological species. Phylogenetically, A. korhonenii is the earliest divergent lineage of the genus Armillaria as inferred from the nucleotide sequences of the Elongation Factor 1-Alpha (EF1a). Morphologically, it is characterized by its ellipsoid to elongate basidiospores, yellowish orange to honey yellow pileus with fibrillose squamules. Mating tests indicated that A. korhonenii is a tetrapolar heterogeneous species and is inter-sterile with all the tested species except partial compatibility with CBSH.

The JinEr mushroom (“Golden Ear”), a globally rare edible and medicinal macrofungus, comprises a symbiotic complex formed by the symbiotic association of Naematelia aurantialba (Tremellomycetes) and Stereum hirsutum (Agaricomycetes). However, the interactions between these fungi and their associated microbiome remain poorly understood. This study employed high-throughput amplicon sequencing, in situ microbial isolation and culture, and microbial confrontation assays to analyze microbial diversity, community structure, and potential functional roles of the endomycotic bacterial community within JinEr basidiomata and its cultivation substrate. Molecular analysis confirmed the heterogenous composition of the basidiomata, revealing N. aurantialba constitutes less than 20% of the fungal biomass, while S. hirsutum predominates, accounting for approximately 80%. Endomycotic fungi accounted for 0.33% (relative abundance) of the fungal community. Prokaryotic analysis identified Delftia and Sphingomonas as the dominant endomycotic bacterial genera within basidiomata, comprising 85.42% of prokaryotic sequences. Endomycotic bacterial diversity differed significantly (p < 0.05) between basidiomata and substrate, indicating host-specific selection. Cultivation-based approaches yielded 140 culturable bacterial isolates (spanning four families and seven genera) from basidiomata core tissues. In vitro co-culture experiments demonstrated that eight representative bacterial strains exhibited compatible growth with both hosts, while one Enterobacteriaceae strain displayed antagonism towards them. These findings confirm that the heterogeneous JinEr basidiomata harbor a specific prokaryotic assemblage potentially engaged in putative symbiotic or commensal associations with the host fungi. This research advances the understanding of microbial ecology in this unique fungal complex and establishes a culture repository of associated bacteria. This collection facilitates subsequent screening for beneficial bacterial strains to enhance the JinEr cultivation system through the provision of symbiotic microorganisms.

Botryosphaeriaceae is the largest family in Botryosphaeriales, consisting of 22 genera. Members of this family have cosmopolitan distribution, occurring in various life modes: endophytic, saprobic and pathogenic, mainly associated with plants. This study aims to investigate plant-associated saprobic microfungi in Yunnan, China. Here, we establish two novel species in Dothiorella , namely D. fusiformis and D. swieteniae . Both sexual and asexual morphs are provided for D. fusiformis . Additionally, we report two new host records of Barriopsis archontophoenicis S. Konta, Boonmee & K.D. Hyde and D. camelliae W.Li Li & Jian K. Liu. Taxonomic boundaries were confirmed based on morphological characteristics coupled with phylogenetic analyses using maximum likelihood (ML) and Bayesian inference (BI) analyses of combined SSU, LSU, ITS, β-tubulin and tef 1-α sequences. Furthermore, the detailed illustrations, comprehensive descriptions, and taxonomic justifications are provided for each species. This study expands our understanding of the taxonomy, diversity and ecological relationships of Botryosphaeriaceae species in China by introducing new species and reporting new host and geographic records.

Armillaria korhonenii , designated as Chinese biological species Q (CBSQ) here, is described as a new species based on phylogenetic and morphological evidence as well as the results of mating tests. This species is the sixteenth biological species of Armillaria reported from China following the discovery of 15 previously known biological species. Phylogenetically, A . korhonenii is the earliest divergent lineage of the genus Armillaria as inferred from the nucleotide sequences of the Elongation Factor 1-Alpha ( EF1a ). Morphologically, it is characterized by its ellipsoid to elongate basidiospores, yellowish orange to honey yellow pileus with fibrillose squamules. Mating tests indicated that A . korhonenii is a tetrapolar heterogeneous species and is inter-sterile with all the tested species except partial compatibility with CBSH.