Ima Fungus最新文献

Historically, Sirococcus (established in 1855) and Gnomoniopsis (proposed in 1893) have been treated as distinct genera within Gnomoniaceae, primarily distinguished by the prevalence of their asexual and sexual morphs, respectively. However, recent molecular data have challenged this distinction. In this study, we re-evaluated the relationship between these two genera using a combined multi-locus phylogeny (ITS, tef1, and tub2) and morphological assessment. Phylogenetic analyses revealed that species of Sirococcus and Gnomoniopsis cluster within a single, robustly supported monophyletic lineage, sharing indistinguishable asexual characteristics. Consequently, we propose to synonymize Gnomoniopsis under Sirococcus following the principle of priority. Thirty-eight new combinations and a new species are proposed. Furthermore, we investigated the life cycle of Sirococcus daii comb. nov., a severe pathogen causing nut rot of Chinese chestnut (Castanea mollissima), for which the teleomorph was previously unknown. Through extensive sampling, we discovered the teleomorph on overwintered leaf litter, confirming the saprobic phase of its life cycle. Additionally, the fungus was isolated from healthy female flowers, young nuts, and husks, suggesting a latent or endophytic infection strategy. Based on these findings, we reconstructed the complete life cycle of S. daii. This study not only resolves the taxonomic controversy surrounding Sirococcus and Gnomoniopsis but also provides crucial epidemiological insights into S. daii, facilitating the development of effective management strategies for chestnut nut rot.

A completely asexual morph of Splanchospora is revealed for the first time. This genus is characterised by clavate-ellipsoid, thick-walled ascospores strongly constricted at the submedian septum, the presence of paraphyses in the conidiomata, and globose to ellipsoid, 1-celled conidia. Through phylogenetic analyses based on the small subunit (SSU) and large subunit (LSU) of the nuclear ribosomal DNA, the nuclear ribosomal internal transcribed spacer (ITS) region, the second largest RNA polymerase II subunit (RPB2) gene, and the translation elongation factor 1-alpha (TEF1) gene, the genus is clarified to belong to the family Neohendersoniaceae (Pleosporales, Dothideomycetes). The type species, Splanchospora ampullacea, is neotypified and found to be a species complex. Because of this, we describe four new Splanchospora species, S. fulviconidia sp. nov., S. microspora sp. nov., S. oblongiconidia sp. nov., and S. pseudomicrospora sp. nov. from the twigs of lindens in Japan. All Splanchospora species examined show slight differences in conidial morphology, such as size, shape, and pigmentation. Species-level analyses suggest that this genus, previously considered to be monotypic, in fact harbours a remarkable diversity of species existing on lindens worldwide.

Mortierellaceae are cosmopolitan, soil-inhabiting fungi that can be found in nearly all terrestrial habitat types and are therefore considered an essential part of the core soil microbiome. Many species of this family are known to endure harsh environments, including highly exposed and nutrient-depleted terrains such as glacier forefields. In these environments, microbial communities are taxonomically and functionally diverse, greatly contributing to nutrient cycling, soil organic matter formation, and plant establishment. However, there is growing understanding that Mortierellaceae diversity in these habitats remains largely undescribed. In this study, we isolated multiple fungal strains belonging to a previously unknown Mortierellaceae taxon from early stages of soil development in calcareous glacier forefields of the Alps and comprehensively characterized them using different tools: physiological tests, detection of associated bacteria, and microscopic observations (e.g., light, fluorescence, and scanning electron microscopy) to visualize their morphology and surface structure. Additionally, whole-genome sequencing and phylogenomics were used to determine their placement within Mortierellaceae. Our results show that the isolated strains represent a new species within a previously undescribed fungal genus. Due to the strains' origin in hidden, calcareous sediments of the earliest soil developmental stages at glacier forefields, we propose the name Cryptocalciella humilis Mandolini, Szedlacsek & Peintner for this fungus.

Powdery mildew is a persistent disease affecting the cultivation of Rosa, a genus of substantial horticultural and economic value worldwide. Despite more than a century of study, the true diversity of powdery mildews infecting roses has remained unclear, largely due to the long-standing and overly broad application of the name Podosphaera pannosa. To reassess this system, we conducted an extensive investigation of powdery mildew specimens infecting Rosa. A total of 112 collections were examined, including recently gathered material from 23 provinces, historical types, representative specimens from the Herbarium Mycologicum Academiae Sinicae (HMAS), China, and a neotype specimen from Germany. Morphological observations combined with phylogenetic analyses (ITS, 28S, and IGS rDNA) resolved several long-standing taxonomic problems and revealed unexpected diversity within the rose powdery mildew complex. Molecular data from Erysiphe rosae provide the first phylogenetic evidence supporting the synonymy of Medusosphaera with Erysiphe. Sphaerotheca rosae, previously treated as a synonym of P. pannosa, is reinstated as a distinct species as Podosphaera rosae comb. nov., and a previously unrecognized lineage is described as Podosphaera rosae-xanthinae sp. nov. In addition, earlier varieties of E. simulans are shown to lack diagnostic morphological or genetic characters and are no longer supported. Taken together, these results demonstrate that powdery mildews on Rosa represent a complex of five species across two genera, structured by host phylogeny. Clear patterns of host preference and distribution indicate a history of co-evolution and ecological differentiation driven by host availability. This study fundamentally revises our understanding of rose powdery mildews, revealing a level of taxonomic and evolutionary complexity much greater than previously recognized and highlighting Rosa as a key host lineage in the diversification of the Erysiphaceae.

Foliar fungal communities are essential components of the plant microbiome, playing a vital role in maintaining plant health and influencing ecosystem dynamics. Despite increasing interest in plant-microbe associations, the drivers shaping foliar fungal community composition remain poorly understood, including the roles of host phylogeny, functional traits, and belowground mycorrhizal symbiosis. We used the MycoPhylo experimental field, in which plant species are planted in a replicated, phylogenetically diverse design, to investigate the influence of host plant identity, mycorrhizal type, and leaf functional traits on foliar fungal assemblages. We examined foliar fungal communities across 158 plots representing 110 distinct plant species using a metabarcoding approach. The resulting operational taxonomic units (OTUs) were dominated by Dothideomycetes (44.5%), Tremellomycetes (12.7%), and Taphrinomycetes (9.0%). Functional guild analysis revealed that plant pathogens and saprotrophs were the most abundant ecological groups. Foliar fungal alpha diversity and community composition were significantly influenced by plant growth form and mycorrhizal association. Although plant deciduousness did not affect fungal richness, it significantly affected fungal community composition. The measured leaf traits (hairiness and thickness) showed the least influence on fungal richness. Mantel tests revealed weak, guild-dependent relationships between host phylogenetic distance and foliar fungal community dissimilarity. Moreover, plant phylogenetic eigenvectors accounted for up to 25.8% of the variation in fungal richness. These findings indicate that host phylogeny and plant traits contribute to-but do not solely determine-the structure of foliar fungal assemblages under field conditions.

Steccherinum and its allied genera represent a morphologically complex group of fungi within the Steccherinaceae. In this study, we investigated, through morphological and multigene phylogenetic analyses, the diversity of odontioid/hydnoid Steccherinum s.l. collected in Brazil. Culture studies were conducted to compare mycelial morphology and growth rates among species, and mating tests were performed to assess sexual compatibility among related taxa. In addition, divergence-time estimates for the Steccherinaceae were generated using a concatenated five-gene dataset to contextualize the evolutionary history of the group. Molecular data revealed eight well-defined neotropical lineages in Steccherinum, including S. larssonii, S. perparvulum, S. subochraceum, and five new species: S. bononiae, S. elegantissimum, S. molle, S. resinaceum, and S. undulatum. The five newly described taxa are morphologically very similar and differ only in subtle diagnostic traits. Two additional new species were identified in Cabalodontia: C. albofulva and C. brunnea. Furthermore, the new combinations C. lincangense and C. tenuissima are proposed based on the phylogenetic data. Phylogenetic analyses also demonstrated that S. perparvulum comprises a species complex with three distinct lineages. Mating tests between two of these lineages showed a lack of sexual compatibility, indicating that they represent separate biological species that cannot be distinguished morphologically. Mycelial culture studies also revealed generally similar morphology with variable growth rates among taxa. Divergence-time estimates indicate a crown age of approximately 86.4 Ma for the Steccherinaceae and a predominantly Cenozoic diversification, with Steccherinum originating in the Eocene. Our findings highlight significant cryptic diversity within Steccherinum in the Neotropics and provide new insights into the taxonomy and phylogeny of the genus.

Dermatophytosis is a common skin infection worldwide. In recent years, Trichophyton mentagrophytes var. indotineae has rapidly emerged as a leading cause of recalcitrant dermatophytosis. Iran shows high genetic diversity within the T. mentagrophytes complex, suggesting local emergence of new genotypes, yet nationwide data remain limited. We performed a one-year multicentre, hospital-based survey of referred cases (September 2023-September 2024) in nine provinces of Iran to describe the current epidemiology of dermatophytosis and to analyse mutations in the squalene epoxidase (SQLE) gene associated with terbinafine (TRB) resistance. Clinical samples were obtained from 2211 patients with suspected dermatophytosis. Dermatophytes were recovered from 1568 samples (71%). Species-specific PCR identified T. mentagrophytes var. indotineae in 1191 cases (76%), confirming it as the dominant agent across all clinical forms, age groups and provinces. The remaining isolates comprised other dermatophytes, mainly other members of the T. mentagrophytes complex, T. tonsurans and Microsporum canis. Trichophyton mentagrophytes var. indotineae caused most cases of tinea cruris, tinea corporis, mixed infections and generalised dermatophytosis. It also accounted for 59% of tinea unguium and 37% of tinea capitis cases. No significant sex bias was observed and most patients were 20-49 years old. The data did not indicate recent introduction of the infection from outside Iran, supporting ongoing local transmission. SQLE sequencing of 410 isolates revealed resistance-associated mutations in 45% of strains, mainly F397L (72%) and L393S (28%), with the highest frequencies in southern provinces. ITS sequencing of a subset of isolates confirmed their identity as T. indotineae and revealed two ITS genotypes, including a dominant genotype VIII and a new sub-genotype XXIX. These findings show that T. indotineae is now the dominant dermatophyte in Iran and carries a substantial burden of SQLE mutations, highlighting the urgent need for continued molecular surveillance and antifungal stewardship.

Entomopathogens constitute a unique and specialized trophic group of fungi, most of which belong to Hypocreales (Sordariomycetes, Ascomycota). In this study, eight species were collected and isolated from China and Thailand. Through comprehensive morphological analyses and multigene phylogenetic studies (ITS, nrSSU, nrLSU, tef1-α, rpb1, rpb2), seven novel species (Ophiocordyceps jinguangensis sp. nov., O. northeastensis sp. nov., Polycephalomyces bannaensis sp. nov., Po. chiangraiensis sp. nov., Pleurocordyceps shibingensis sp. nov., Pl. tengchongensis sp. nov., and Dingleyomyces yunnanensis sp. nov.) and one known species (O. formicarum) were identified. Additionally, the pairwise homoplasy index (PHI) test results and morphological differences between the new species and their closely related taxa are provided. Notably, as the number of reported hirsutella-like species continues to increase, their phylogenetic placement has become increasingly unclear in previous classifications. To address this issue, this paper presents the first comprehensive summary of the distribution of hirsutella-like species within the families Ophiocordycipitaceae and Polycephalomycetaceae, along with an analysis of the similarities and differences in their phialidic characteristics. These findings significantly expand our knowledge of the diversity, taxonomy, and phylogenetic relationships of entomopathogenic fungi in these families, providing a valuable framework for future studies on their ecology and evolution.

Ambrosia beetles (Coleoptera, Curculionidae) form obligate nutritional symbioses with ambrosia fungi cultivated within their galleries. Among them, the pinhole borers (Platypodinae) are predominantly tropical, with only two representatives native to Europe. One of them, the rare and understudied Treptoplatypus oxyurus, primarily colonises Abies alba. We investigated its fungal symbionts using a cultivation-dependent approach. We identified three numerically dominant associates in the prothorax containing mycangia: Candida schatavii, Magnusiomyces fungicola, and a novel member of Ophiostomatales. The latter, Wilhelmdebeerea oxyuri gen. et sp. nov., was the most abundant and exhibited both leptographium-like and hyalorhinocladiella-like morphs. Additionally, two new yeast species of low abundance and uncertain ecological roles were isolated and described: Blastobotrys sasensis sp. nov. and Sugiyamaella casensis sp. nov., both belonging to the family Trichomonascaceae (Dipodascales). Multigene and phylogenomics analyses confirmed the distinct taxonomic placement of all three new species. The ecological roles of the identified fungi and the strength of their association with T. oxyurus require confirmation through further studies at additional locations. Our findings reveal a previously undocumented fungal diversity tightly linked to a unique pinhole borer, T. oxyurus, thereby enriching our understanding of the fungi associated with conifer-colonising beetles and their ecological and biotechnological importance.

Complex life-cycles are common among fungi. Dimorphism in basidiomycetes involves alternation between a unicellular yeast phase and a filamentous phase, frequently forming basidiomata. Here we have studied the dimorphic life cycle of the lichen-inhabiting basidiomycetes in the Tremella caloplacae species complex, with particular focus on the newly distinguished Tremella parietinae. Using FISH-CLSM, PCR and Sanger sequencing, we have investigated the presence and distribution of the different life-cycle phases of T. parietinae within the lichen Xanthoria parietina, and also conducted an exploratory investigation into the presence of a Tremella yeast phase in other lichens of the Teloschistaceae. We could show that the filamentous phase of T. parietinae is restricted to the hymenium of X. parietina, whereas the yeast phase also grows elsewhere in the thallus. Tremella caloplacae s. str. is detected by PCR in Calogaya, Flavoplaca and Gyalolechia lichens, whereas its basidiomata are restricted to Variospora lichens. These findings suggests different lichen-specificity of T. caloplacae in the different phases of its life-cycle.