Gnomoniopsis comprises parasitic, endophytic, and saprophytic fungi. Since its establishment, this genus has presented considerable taxonomic challenges owing to extensive morphological overlap among species, rendering traditional classification systems that rely predominantly on phenotypic characteristics no longer applicable. To resolve the current taxonomic confusion and clarify the species diversity, phylogenetic relationships, and genomic adaptive characteristics of Gnomoniopsis , the present study was carried out. In this study, the internal transcriptional spacer (ITS), translation extension factor 1-α ( tef1 ), and partial beta-tubulin ( tub2 ) were analyzed and combined to observe morphological characteristics of Gnomoniopsis . The isolates were identified from chestnut ( Castanea ), Embelia vestita , tea ( Camellia sinensis ), and other hosts in Sichuan Province, as well as from Quercus species and partial leaf rot from Fujian Province. Nine new species, namely G. xiaoheijiangensis sp. nov ., G. embeliae sp. nov ., G. yunvfengensis sp. nov ., G. quercus sp. nov ., G. ledongensis sp. nov ., G. yonganensis sp. nov ., G. conghuaensis sp. nov ., G. loropetali sp. nov ., and G. qixiensis sp. nov ., were obtained. Phylogenomic analysis based on 7,942 orthologous proteins’ clusters revealed distinct species boundaries within Gnomoniopsis . Phylogenomics has thus effectively resolved the ambiguous phylogenetic relationships in this genus. This work identifies nine previously undescribed Gnomoniopsis species, clarifies the species diversity and conserved genomic characteristics within the genus, and lays a foundation for subsequent taxonomic analyses of Gnomoniopsis .
Lichen-associated Cystobasidiomycetes have been reported from a wide range of lichens worldwide. Previous studies proposed that lichen-associated Cystobasidiomycetes may be involved in the development of the thallus cortex, suggesting also a contribution to the construction of thallus architecture within the Parmeliaceae . However, Parmeliaceae do not include species with ecorticate thalli. In contrast, Arthoniales encompass a wide diversity of thallus growth forms, including both corticate and ecorticate types, making this order a suitable model to test this hypothesis across a broader evolutionary context. Furthermore, Cystobasidiomycetes have not yet been studied in Arthoniales . This study aims therefore to (1) characterize the diversity of Arthoniales -associated Cystobasidiomycetes ; (2) investigate their selectivity with respect to mycobiont partners and the ecological factors shaping their distribution, and (3) test whether their distribution is consistent with a proposed role in cortex formation and thallus architecture in Arthoniales . The ITS region of Cystobasidiomycetes was sequenced from 169 lichen samples (in majority Arthoniales ) and an exhaustive maximum-likelihood phylogeny, including our sequences and all sequences found in GenBank, was inferred using IQ-tree. The effects of substratum, climate, host taxonomy and geographic location on the distribution of Cystobasidiomycetes were assessed using variation partitioning. Cystobasidiomycetes were found in 60 of our samples. Our sequences belonged to 39 Cystobasidiomycetes OTUs, 21 of which were detected in Arthoniales thalli, and eight of them represent unknown lineages. Globally, OTU selectivity was variable. However, most OTU’s exhibited a preference for particular groups of mycobionts. Mycobiont taxonomy emerged as the primary factor shaping lichen-derived Cystobasidiomycetes community composition. Climate and substrate likely also influence their distribution, although their effects may be underestimated, due to an unbalanced dataset, dominated by sequences from extra-tropical and corticolous specimens. Finally, no evidence was found to support a correlation between Cystobasidiomycetes detection, thallus growth form or cortex presence in Arthoniales . Overall, these results suggest that lichen-derived Cystobasidiomycetes OTUs largely form lineages distinct from those represented by Cystobasidiomycetes from other sources. However, the lifestyle of many sequences remains uncertain because they were obtained through environmental sequencing. Despite their generally low selectivity, a consistent pattern of mycobiont preference was observed across Cystobasidiomycetes orders. This pattern was not associated with thallus growth form or the presence of a cortex.
The family Verrucosporaceae , a recently resurrected lepiotoid fungal lineage, has historically been subject to unstable generic delimitations and polyphyletic infrageneric classifications. To resolve these taxonomic ambiguities, we conducted comprehensive morphological examinations and multi-locus phylogenetic analyses (nrITS, nrLSU, rpb2 , and tef1-α ) based on extensive specimen sampling across China. Our results strongly support the monophyly of Verrucosporaceae and clarify the evolutionary boundaries among its core genera, including Cystolepiota , Echinoderma , Lepiota , Pulverolepiota , and Smithiomyces . Within Lepiota , seven formally defined sections and four unplaced distinct clades were recovered. A novel subsection, Lepiota sect. Eriophorae subsect. Pseudocystolepiotae , is proposed to accommodate an evolutionary transitional lineage between Cystolepiota and Lepiota sect. Eriophorae . Based on an integrative taxonomic approach, we describe 17 species new to science, introduce three new combinations, and reinstate Lepiota squamulosa . Furthermore, micromorphological observations indicate that the microstructure of the pileus and stipe coverings shares structural homology, reinforcing its reliability as a criterion for infrageneric delimitation. Ultimately, this study expands the current understanding of cryptic diversity within Verrucosporaceae in China and provides useful morphological and phylogenetic data for future evolutionary studies on lepiotaceous fungi.
Decomposing litter is a critical driver of fuel bed formation and forest fire regimes, yet how divergent plant fire-adaptive strategies influence litter chemistry and subsequent fungal decomposition dynamics remains poorly understood. Here, we conducted a 6-month reciprocal litterbag experiment by incubating litter from two contrasting pine species—the fire-tolerant Pinus taiwanensis and the fire-avoiding P. morrisonicola —in both their own native habitat and that of the other species, coupled with genome-resolved metagenomics to track fungal succession and lignocellulolytic functional profiles. We found that the fire-avoiding P. morrisonicola exhibited significantly accelerated decomposition, driven by inherently lower initial C:N ratio and less recalcitrant litter, whereas the fire-tolerant P. taiwanensis exhibited slower decomposition rates. Metagenomic profiling revealed a distinct functional succession underlying this process. Early decomposition was dominated by Ascomycota (e.g., Leotiomycetes ), which rapidly colonized the litter to initiate biopolymer breakdown. As easily decomposable substrates depleted, a functional shift occurred. Specifically, the highly recalcitrant P. taiwanensis litter selectively recruited Basidiomycota (e.g., Agaricales and Trechisporales ) equipped with diverse lignin-modifying enzymes, reflected by a late-stage temporal surge in ligninolytic gene abundances. Ultimately, these findings demonstrate that plant fire-adaptive strategies act as a strong filter, shaping litter chemistry to drive specific taxonomic and functional fungal succession. This study provides a mechanistic understanding of the eco-evolutionary linkage between plant traits, microbiome assembly, and ecosystem-level fire dynamics.
Uncovering the identity of “dark fungi” is crucial for understanding fungal taxonomy, diversity, and phylogenetic relationships. Previous exploratory analysis of the mycorrhizal fungi of the partially mycoheterotrophic orchid Nervilia nipponica revealed an association with a particular group of Agaricomycetes, tentatively designated “unidentified Agaricomycetes X” (uAX). Two culture strains were successfully isolated from the mycorrhiza, which enabled the phylogenetic position of this fungus to be determined using ultrastructural and multigene phylogenetic analyses. Transmission electron microscopy observations of the two cultures of uAX revealed that the dolipore septum is associated with perforate septal pore caps (SPCs), the margins of which are reflexed outwards. This combination of characters has not previously been reported in any order of Basidiomycota. Combined phylogenetic analyses based on sequence data from four loci [5.8S and 28S ribosomal DNA (rDNA), translation elongation factor 1-α, and RNA polymerase II second large subunit] indicate that uAX is an early-diverging clade of Agaricomycetes that cannot be accommodated in any known order of Basidiomycota. The name Reflexicalyptrales is proposed here for this new order of Basidiomycota. Furthermore, BLAST searches of the internal transcribed spacers of nuclear ribosomal DNA (nrDNA) and phylogenetic analyses reveal that closely related taxa have previously been detected in soil, leaf litter, and living root samples collected at various locations worldwide. This suggests that the group is ubiquitously distributed and probably exhibits a saprotrophic lifestyle
