Resolving deep phylogenetic relationships remains a central challenge in evolutionary biology due to processes like incomplete lineage sorting (ILS) and introgression/hybridization (IH). Incorporating newly generated genomic data from 121 genome skimming datasets across 98 Pluteineae species, we reconstructed the most robust phylogenetic framework for Pluteaceae, using 672 single-copy orthologs and systematically investigated the underlying causes of hard phylogenetic conflicts. Our data provide evidence for widespread high-level ILS and IH among Pluteaceae. Specifically in Pluteus sect. Pluteus, , phylogenetic network analyses revealed extensive introgression events. These complex IH events may account for the high degree of phylogenetic conflicts within sect. Pluteus.. A divergence time analysis was performed to reconstruct the evolutionary history and revealed that most species emerged between 50 and 15 Ma. We revised the framework for the genus Pluteus, , which comprises two subgenera and four sections. In addition, we employed a taxonomic approach that, based on a multispecies coalescent model inferred by Bayesian phylogenetics and phylogeography (BPP) combined with morphological and ecological criteria, further explores the species delimitation within Pluteaceae. To avoid excessive species splitting, we recommend adopting a BPP support (> 0.995) as a criterion for testing the independence of new species in Pluteaceae, incorporating molecular, ecological, and morphological traits. Having implemented the above-mentioned approaches, this study has recognized and documented a total of 82 species of Pluteaceae in China, with descriptions of a new section and seven new species. Keys for identification of the species are provided.
The order Xenasmatales comprises a diverse group of ecologically significant fungi, yet its species diversity remains insufficiently documented, particularly in understudied regions. Seventeen newly discovered species display macro-and micro-morphological characteristics consistent with the genus Xenasmatella, including membranous to coriaceous basidiomata, pleural basidia, and warted basidiospores. These species also exhibit distinctive morphological traits, such as variations in hymenophoral surface structure and basidiospore morphometrics, that distinguish them from previously described taxa. Phylogenetic analyses of ITS and nLSU sequences indicate that all the newly reported taxa form distinct, independent lineages within Xenasmatales. Phylogenetic trees based on a combined dataset of ITS and nLSU markers further confirm the placement of these taxa within the order. The new species were collected from 15 provinces or autonomous regions across China, encompassing a range of temperate, subtropical, tropical, and alpine-plateau climates. The diversity of climates and pristine habitats contributed to the discovery of this previously unrecognized diversity. The integration of morphological data with multi-locus phylogenetic analyses provides robust support for the recognition of these 17 new species. For each species, a description, illustrations, notes, phylogenetic analysis results, and comparisons with closely related taxa are presented. Additionally, an identification key to the 28 accepted species of Xenasmatella in China is provided.
The generic boundaries and phylogenetic relationships within the Leucoagaricus-Leucocoprinus sensu lato complex have long been a focal point of taxonomic debate. Recently, integrative phylogenomic studies have re-evaluated this group, accommodating it within the newly established subfamily Leucocoprinoideae and recognizing several novel genera. Despite these updated generic frameworks, clarifying species-level boundaries and comprehensively understanding morphological evolutionary patterns within this hyper-diverse complex require further exploration. Based on extensive taxon sampling, multi-locus phylogenetic analyses, and detailed micro-morphological assessments, we investigated the evolutionary relationships within this group. Our analyses demonstrate that Leucoagaricus comprises five major molecular clades encompassing two primary morphological assemblages: the orange-red La. rubrotinctus complex and the whitish La. serenus complex. Concurrently, Leucocoprinus s.l. is resolved into four major clades alongside several transitional lineages. Supported by this comprehensive evidence, we formally describe 41 novel species and report two new geographic records from China. Furthermore, in alignment with the broadly circumscribed generic concept adopted herein, we reinstate the original Leucocoprinus combinations for 60 species and propose eight new combinations into this genus. Mapping specific diagnostic traits onto the phylogeny indicates widespread morphological homoplasy across distantly related lineages. Finally, we provide detailed morphological descriptions and line drawings for all new taxa and records, along with specialized identification keys for species exhibiting fresh guttation or greenish to bluish discoloration upon drying.
