Xylaria karyophthora: a new seed-inhabiting fungus of Greenheart from Guyana

Phylogenetic analysis of termite-associated Xylaria from Africa reveals hidden diversity

Fungus-farming termite colonies host members of the genus Xylaria as stow-away fungi that emerge from deteriorating fungal gardens (combs) or dying termite nests. Fungus-farming termites originated in Africa, where the highest host diversity - eleven termite genera - exists, and later colonised parts of Asia, where five extant termite genera are known. Theory predicts that symbiont diversity should correlate with host diversity, but while 17 termite-associated Xylaria species have been described from Asia, a mere three African species have been formally described. This suggests that the diversity of termite-associated Xylaria in Africa is underestimated due to under-sampling. To test this, we obtained 34 Xylaria isolates from 20 termite colonies in Côte d'Ivoire and placed them in a multi-locus phylogenetic analysis alongside 278 Xylaria and outgroup specimens. This revealed 18 putatively novel Xylaria species, confirming our hypothesis. In addition, our findings revealed the capacity for termite-associated Xylaria species to colonize fungus gardens associated with diverse termite host genera, and that individual termite colonies can host multiple Xylaria species. Given the relatively limited scope of our sampling, including Xylaria strains derived from only four of 11 farming termite genera, it is imperative that substantial diversity likely remains to be discovered, particularly in Africa.

The contribution of tropical long-term studies to mycology

Fungi are arguably the most diverse eukaryotic kingdom of organisms in terms of number of estimated species, trophic and life history strategies, and their functions in ecosystems. However, our knowledge of fungi is limited due to a distributional bias; the vast majority of available data on fungi have been compiled from non-tropical regions. Far less is known about fungi from tropical regions, with the bulk of these data being temporally limited surveys for fungal species diversity. Long-term studies (LTS), or repeated sampling from the same region over extended periods, are necessary to fully capture the extent of species diversity in a region, but LTS of fungi from tropical regions are almost non-existent. In this paper, we discuss the contributions of LTS of fungi in tropical regions to alpha diversity, ecological and functional diversity, biogeography, hypothesis testing, and conservation-with an emphasis on an ongoing tropical LTS in the Pakaraima Mountains of Guyana. We show how these contributions refine our understanding of Fungi. We also show that public data repositories such as NCBI, IUCN, and iNaturalist contain less information on tropical fungi compared to non-tropical fungi, and that these discrepancies are more pronounced in fungi than in plants and animals.

Revisiting Xylaria diversity in Southern China: Descriptions of 40 new species

The genus Xylaria comprises a diverse group of fungi with a global distribution and significant ecological importance, known for being a source of bioactive secondary metabolites with antibacterial, antioxidative, anticarcinogenic, and additional properties. In this study, we present a comprehensive taxonomic revision of the species of Xylaria found in some parts of southern China, characterized by an extensive multilocus phylogeny analysis based on internal transcribed spacer (ITS), TUB2 (β‐tubulin), and DNA‐directed RNA polymerase II subunit 2 (rpb2) gene regions. Morphological examination and detailed comparative analyses of the collected specimens were conducted to determine the distinctiveness of each species. The multilocus phylogeny approach allowed us to infer evolutionary relationships and assess species boundaries accurately, leading to the identification of 40 novel Xylaria species hitherto unknown to science. The newly described species are: X. baoshanensis, X. bawanglingensis, X. botryoidalis, X. dadugangensis, X. doupengshanensis, X. fanglanii, X. glaucae, X. guizhouensis, X. japonica, X. jinghongensis, X. jinshanensis, X. kuankuoshuiensis, X. liboensis, X. negundinis, X. orbiculati, X. ovata, X. pseudoanisopleura, X. pseudocubensis, X. pseudobambusicola, X. pseudoglobosa, X. pseudohemisphaerica, X. pseudohypoxylon, X. puerensis, X. qianensis, X. qiongzhouensis, X. rhombostroma, X. serratifoliae, X. shishangensis, X. shuqunii, X. shuangjiangensis, X. sinensis, X. tongrenensis, X. umbellata, X. xishuiensis, X. yaorenshanensis, X. yinggelingensis, X. yumingii, X. yunnanensis, X. zangmui, and X. zonghuangii. The study's findings shed light on the distinctiveness of the newly described species, supported by both morphological distinctions and phylogenetic relationships with their close relatives. This taxonomic revision significantly contributes to our understanding the diversity of Xylaria in China and enriches the knowledge of fungal biodiversity worldwide.

Multi-Gene Phylogenetic Analyses Reveals Heteroxylaria Gen. Nov. and New Contributions to Xylariaceae (Ascomycota) from China

An in-depth study of the phylogenetic relationships of Xylaria species associated with nutshells of fruits and seeds within the genus Xylaria and related genera of Xylaceaecea was conducted in China. The multi-gene phylogenetic analyses were carried out based on ITS, RPB2, and TUB sequences of 100 species of 16 known genera in Xylariaceae around the world. Based on molecular phylogenetic analyses, morphological observations, and ecological habitats, a new genus, Heteroxylaria, is established to accommodate four new species, viz. H. cordiicola, H. juglandicola, H. meliicola, and H. terminaliicola, and four new combinations, viz. H. oxyacanthae, H. palmicola, H. reevesiae, and H. rohrensis. The genus is characterized by cylindrical stromata with conspicuous to inconspicuous perithecial mounds, surface black, having brown to dark brown ascospores with a germ slit, and it grows on nutshell of fruits. The combined ITS+RPB2+TUB sequence dataset of representative taxa in the Xylariaceae demonstrate that Heteroxylaria is grouped with Hypocreodendron but forms a monophyletic lineage. All novelties described herein are morphologically illustrated and compared to similar species and phylogeny is investigated to establish new genera and species.

Morphology and multigene phylogeny reveal four new Xylaria (Xylariales, Xylariaceae) species from karst region in China

This study presents the identification of four novel Xylaria species, discovered in the karst region of China. The discovery was facilitated by a rigorous analysis that encompassed both morpho-anatomical features and multi-locus phylogenetics utilizing sequences from the ITS, rpb2, and TUB2 loci. The newly identified species are designated as Xylariajichuanii sp. nov., X.nanningensis sp. nov., X.orientalis sp. nov., and X.taiyangheensis sp. nov. The distinction of these species from their known counterparts was verified through comparison of morphological features and phylogenetic analysis. The study further provides detailed morphological descriptions, illustrative representations, and a phylogenetic tree, all of which contribute to the taxonomic positioning of these novel species.

Novel discoveries of Xylariomycetidae (Ascomycota) taxa from peat swamp forests and other terrestrial habitats in Thailand

In a comprehensive survey of fungi conducted in the northern (Chiang Rai Province) and southern (Narathiwat Province) regions of Thailand, several xylariales-like specimens were discovered. Through the integration of molecular phylogeny and morphological analyses, one previously undocumented taxon, Oxydothisnarathiwatensis sp. nov., was identified, along with Xylariabawanglingensis and Hypoxylonhypomiltum as new host and geographical records from Afzeliaxylocarpa, and Dalbergiacana, respectively. In addition, Annulohypoxylonthailandicum was identified as a new host record from Swieteniamacrophylla in Thailand. The morphological characters, including ascomata, asci, and ascospores, were compared with known Oxydothis, Xylaria, Hypoxylon, and Annulohypoxylon species. Multi-locus phylogenetic analyses based on ITS, LSU, and SSU (for Oxydothidaceae), ITS, rpb2, tub2, and act (for Xylariaceae), and ITS, LSU, rpb2, and tub2 (for Hypoxylaceae) gene regions were carried out to refine the taxonomic classifications of these specimens further. This research contributes to understanding fungal diversity in these ecologically significant regions, highlighting insights into the relationships among xylariales-like species.

Multi-gene phylogenetic and taxonomic contributions to Xylaria (Ascomycota) associated with fallen fruits from China

Morphological and phylogenetic analyses on samples of Xylaria species associated with fallen fruits from China were carried out, and two new species were described, namely X.aleuriticola and X.microcarpa. Xylariaaleuriticola is found on fallen fruits of Aleuritesmoluccana, and characterized by stromata dichotomously branched several times with long acute sterile apices, fertile parts roughened with perithecia and tomentose, and ellipsoid to fusiform ascospores. Xylariamicrocarpa differs in its very small stromata with dark brown tomentum, light brown ascospores with an inconspicuous straight germ slit, and grows on leguminous pods. The differences between the new species and morphologically similar species are discussed. Phylogenetic analyses on ITS-RPB2-TUB sequences confirmed that the two species are clearly separated from other species of the genus Xylaria. Xylarialiquidambaris is reported as a new record from China. A key to the Xylaria species associated with fallen fruits and seeds reported from China is provided to facilitate future studies of the genus.

Four New Pale-Spored Species of Xylaria (Xylariaceae, Xylariales) with a Key to Worldwide Species on Fallen Fruits and Seeds

Xylaria, a large and cosmopolitan genus of Ascomycota, plays an important ecological role in forest ecology as wood-decomposers, and serve as a source of bioactive secondary metabolites. The present work concerns a survey of Xylaria from Southwest China. Four new species of Xylaria with pale-colored ascospores associated with fallen fruits and seeds are described and illustrated based on morphological and phylogenetic evidences. The phylogeny inferred from a combined dataset of ITS-RPB2-β-tubulin sequences supports these four species as distinct species. The four new taxa, namely Xylariarogersii, X. schimicola, X. theaceicola, and X. wallichii, are compared and contrasted against morphologically similar species. A dichotomous identification key to all the accepted species of Xylaria associated with fallen fruits and seeds is given.

Metagenomic Analyses of the Soybean Root Mycobiome and Microbiome Reveal Signatures of the Healthy and Diseased Plants Affected by Taproot Decline

Invading pathogens interact with plant-associated microbial communities, which can be altered under the pressure of pathogen infection. Limited information exists on plant-microbe interactions occurring during natural outbreaks in agricultural fields. Taproot decline (TRD) of soybean is an emerging disease caused by Xylaria necrophora. TRD disease occurrence and yield loss associated with TRD are outstanding issues in soybean production. We applied nuclear ribosomal DNA Internal Transcribed Spacers and 16S rRNA gene taxonomic marker sequencing to define the composition of the fungal and bacterial communities associated with healthy and diseased soybean roots collected from the Mississippi Delta. The plant compartment was a significant factor regulating taxonomic diversity, followed by the disease status of the plant. TRD impacted the root endophytes, causing imbalances; at the intermediate and advanced stages of TRD, X. necrophora decreased mycobiome diversity, whereas it increased microbiome richness. Networks of significant co-occurrence and co-exclusion relationships revealed direct and indirect associations among taxa and identified hubs with potential roles in assembling healthy and TRD-affected soybean biomes. These studies advance the understanding of host-microbe interactions in TRD and the part of biomes in plant health and disease.

Fungal diversity notes 1387-1511: taxonomic and phylogenetic contributions on genera and species of fungal taxa

This article is the 13th contribution in the Fungal Diversity Notes series, wherein 125 taxa from four phyla, ten classes, 31 orders, 69 families, 92 genera and three genera incertae sedis are treated, demonstrating worldwide and geographic distribution. Fungal taxa described and illustrated in the present study include three new genera, 69 new species, one new combination, one reference specimen and 51 new records on new hosts and new geographical distributions. Three new genera, Cylindrotorula (Torulaceae), Scolecoleotia (Leotiales genus incertae sedis) and Xenovaginatispora (Lindomycetaceae) are introduced based on distinct phylogenetic lineages and unique morphologies. Newly described species are Aspergillus lannaensis, Cercophora dulciaquae, Cladophialophora aquatica, Coprinellus punjabensis, Cortinarius alutarius, C. mammillatus, C. quercoflocculosus, Coryneum fagi, Cruentomycena uttarakhandina, Cryptocoryneum rosae, Cyathus uniperidiolus, Cylindrotorula indica, Diaporthe chamaeropicola, Didymella azollae, Diplodia alanphillipsii, Dothiora coronicola, Efibula rodriguezarmasiae, Erysiphe salicicola, Fusarium queenslandicum, Geastrum gorgonicum, G. hansagiense, Helicosporium sexualis, Helminthosporium chiangraiensis, Hongkongmyces kokensis, Hydrophilomyces hydraenae, Hygrocybe boertmannii, Hyphoderma australosetigerum, Hyphodontia yunnanensis, Khaleijomyces umikazeana, Laboulbenia divisa, Laboulbenia triarthronis, Laccaria populina, Lactarius pallidozonarius, Lepidosphaeria strobelii, Longipedicellata megafusiformis, Lophiotrema lincangensis, Marasmius benghalensis, M. jinfoshanensis, M. subtropicus, Mariannaea camelliae, Melanographium smilaxii, Microbotryum polycnemoides, Mimeomyces digitatus, Minutisphaera thailandensis, Mortierella solitaria, Mucor harpali, Nigrograna jinghongensis, Odontia huanrenensis, O. parvispina, Paraconiothyrium ajrekarii, Parafuscosporella niloticus, Phaeocytostroma yomensis, Phaeoisaria synnematicus, Phanerochaete hainanensis, Pleopunctum thailandicum, Pleurotheciella dimorphospora, Pseudochaetosphaeronema chiangraiense, Pseudodactylaria albicolonia, Rhexoacrodictys nigrospora, Russula paravioleipes, Scolecoleotia eriocamporesi, Seriascoma honghense, Synandromyces makranczyi, Thyridaria aureobrunnea, Torula lancangjiangensis, Tubeufia longihelicospora, Wicklowia fusiformispora, Xenovaginatispora phichaiensis and Xylaria apiospora. One new combination, Pseudobactrodesmium stilboideus is proposed. A reference specimen of Comoclathris permunda is designated. New host or distribution records are provided for Acrocalymma fici, Aliquandostipite khaoyaiensis, Camarosporidiella laburni, Canalisporium caribense, Chaetoscutula juniperi, Chlorophyllum demangei, C. globosum, C. hortense, Cladophialophora abundans, Dendryphion hydei, Diaporthe foeniculina, D. pseudophoenicicola, D. pyracanthae, Dictyosporium pandanicola, Dyfrolomyces distoseptatus, Ernakulamia tanakae, Eutypa flavovirens, E. lata, Favolus septatus, Fusarium atrovinosum, F. clavum, Helicosporium luteosporum, Hermatomyces nabanheensis, Hermatomyces sphaericoides, Longipedicellata aquatica, Lophiostoma caudata, L. clematidis-vitalbae, Lophiotrema hydei, L. neoarundinaria, Marasmiellus palmivorus, Megacapitula villosa, Micropsalliota globocystis, M. gracilis, Montagnula thailandica, Neohelicosporium irregulare, N. parisporum, Paradictyoarthrinium diffractum, Phaeoisaria aquatica, Poaceascoma taiwanense, Saproamanita manicata, Spegazzinia camelliae, Submersispora variabilis, Thyronectria caudata, T. mackenziei, Tubeufia chiangmaiensis, T. roseohelicospora, Vaginatispora nypae, Wicklowia submersa, Xanthagaricus necopinatus and Xylaria haemorrhoidalis. The data presented herein are based on morphological examination of fresh specimens, coupled with analysis of phylogenetic sequence data to better integrate taxa into appropriate taxonomic ranks and infer their evolutionary relationships.

Xylaria necrophora, sp. nov., is an emerging root-associated pathogen responsible for taproot decline of soybean in the southern United States

Taproot decline (TRD) is a disease of soybean that has been reported recently from the southern United States (U.S.). Symptoms of TRD include foliar interveinal chlorosis followed by necrosis. Darkened, charcoal-colored areas of thin stromatic tissue are evident on the taproot and lateral roots along with areas of necrosis within the root and white mycelia within the pith. Upright stromata typical of Xylaria can be observed on crop debris and emerging from infested roots in fields where taproot decline is present, but these have not been determined to contain fertile perithecia. Symptomatic plant material was collected across the known range of the disease in the southern U.S., and the causal agent was isolated from roots. Four loci, ⍺-actin (ACT), β-tubulin (TUB2), the nuclear rDNA internal transcribed spacers (nrITS), and the RNA polymerase subunit II (RPB2), were sequenced from representative isolates. Both maximum likelihood and Bayesian phylogenetic analyses showed consistent clustering of representative TRD isolates in a highly supported clade within the Xylaria arbuscula species complex in the "HY" clade of the family Xylariaceae, distinct from any previously described taxa. In order to understand the origin of this pathogen, we sequenced herbarium specimens previously determined to be "Xylaria arbuscula" based on morphology and xylariaceous endophytes collected in the southern U.S. Some historical specimens from U.S. herbaria collected in the southern region as saprophytes as well as a single specimen from Martinique clustered within the "TRD" clade in phylogenetic analyses, suggesting a possible shift in lifestyle. The remaining specimens that clustered within the family Xylariaceae, but outside of the "TRD" clade, are reported. Both morphological evidence and molecular evidence indicate that the TRD pathogen is a novel species, which is described as Xylaria necrophora.

New curtachalasin from the Xylaria sp. DO 1801

One new cytochalasin, named curtachalasin Q (1), together with 8 known cytochalasins were isolated from the ethyl acetate extract of the Xylaria sp. DO1801. The structure of the new compound was elucidated on the basis of IR, UV, HR-ESI-MS, NMR spectra and X-ray diffraction. Compound 1 and 2 were not cytotoxic (IC₅₀>50uM) against four tumour cell lines (SW-1990, ASPC-1, HepG2 and Hep3B).