The Russula globispora lineage is a morphologically and phylogenetically well-defined group of ectomycorrhizal fungi occurring in various climatic areas. In this study we performed a multi-locus phylogenetic study based on collections from boreal, alpine and arctic habitats of Europe and Western North America, subalpine collections from the southeast Himalayas and collections from subtropical coniferous forests of Pakistan. European and North American collections are nearly identical and probably represent a single species named R. dryadicola distributed from the Alps to the Rocky Mountains. Collections from the southeast Himalayas belong to two distinct species: R. abbottabadensis sp. nov. from subtropical monodominant forests of Pinus roxburghii and R. tengii sp. nov. from subalpine mixed forests of Abies and Betula. The results suggest that speciation in this group is driven by a climate disjunction and adaptation rather than a host switch and geographical distance.

Fungal endophytes live asymptomatically within plants and are widespread inhabitants of leaves and other organs (Wilson, 1995). Similarly, endolichenic fungi live asymptomatically within lichens, occurring in healthy lichen thalli worldwide (Arnold et al., 2009). Endophytes and endolichenic fungi are ecologically similar, living in symbiosis with either a plant or the photobionts of lichens (Arnold et al., 2009), and both functional groups represent the same major lineages of fungi (U’Ren et al., 2012).

Powdery mildews are highly destructive fungal plant pathogens that have a significant economic impact on both agricultural and ecological systems worldwide. The intricate relationship between powdery mildews and their host plants has led to cospeciation. In this study, we conducted an extensive evaluation of powdery mildew hosts to provide an updated understanding of the host ranges and distributions of these fungi. The “United States National Fungus Collections Fungus-Host Dataset” is the primary source of information for our analyses. The analysis of the dataset demonstrated the worldwide prevalence of powdery mildews; the data contained over 72,000 reports of powdery mildews, representing ∼8.7% of all host-fungal records. We have updated the taxonomy and nomenclature of powdery mildews. In total, powdery mildews infect ∼10,125 host taxa belonging to 205 families of flowering plants, which accounts for 1,970 genera in 200 countries across six continents. Furthermore, we estimate that powdery mildews infect approximately 2.9% of described angiosperm species. Our study underscores the need for regular updates on powdery mildew host information due to the continuously evolving taxonomy and the discovery of new host taxa. Since 1986, we estimate an additional 1,866 host taxa, 353 genera, and 36 families have been reported. Additionally, the identification of powdery mildew hosts provides valuable insights into the coevolutionary dynamics between the fungi and their plant hosts. Overall, this updated list provides valuable insights into the taxonomy and geographic distribution of powdery mildew species, which builds upon the previous work of Amano in 1986. Discerning the geographic spread and host range of economically significant plant pathogens is vital for biosecurity measures and identifying the origins and expansion of potentially harmful pathogens.

The literature on teleomorph-anamorph connections in the Orbiliaceae and the position of the family in the Leotiales is reviewed. 18S data show that the Orbiliaceae occupies an isolated position in relationship to the other members of the Leotiales which have so far been studied. The following form genera have been studied in cultures derived from ascospores of Orbiliaceae: Anguillospora, Arthrobotrys, Dactylella, Dicranidion, Helicoon, Monacrosporium, Trinacrium and conidial types that are referred to as being Idriella-like. Characteristics of the anamorphs are discussed and illustrated. Analyses of the ITS region of several of the isolates indicate that there are several well-supported clades within the Orbiliaceae. These clades can be recognized based on the anamorphs produced. They are: an Arthrobotrys-Monacrosporium clade, a Dicranidion clade, and a Helicoon clade. Outside of these clades is a well-supported clade which contains two Arthrobotrys isolates which were derived from conidia produced on natural substrates. The taxonomic and phylogenetic implications of this information are discussed. The Orbiliaceae occur in nature on substrates that are either continually wet or on substrates that periodically dry out. Field observations indicate that those taxa which occur on wet substrates produce perennial mycelia. Some discussion is provided on the way in which scientific information is viewed and can be used.

Arthropod–fungus interactions involving the Laboulbeniomycetes have been pondered for several hundred years. Early studies of Laboulbeniomycetes faced several uncertainties. Were they parasitic worms, red algal relatives, or fungi? If they were fungi, to which group did they belong? What was the nature of their interactions with their arthropod hosts? The historical misperceptions resulted from the extraordinary morphological features of these oddly constructed ectoparasitic fungi. More recently, molecular phylogenetic studies, in combination with a better understanding of life histories, have clearly placed these fungi among filamentous Ascomycota (subphylum Pezizomycotina). Species discovery and research on the classification of the group continue today as arthropods, and especially insects, are routinely collected and examined for the presence of Laboulbeniomycetes. Newly armed with molecular methods, mycologists are poisedto use Laboulbeniomycetes–insect associations as models for the study of a variety of basic evolutionary and ecological questions involving host–parasite relationships, modes of nutrient intake, population biology, host specificity, biological control, and invasion biology. Collaboration between mycologists and entomologists is essential to successfully advance knowledge of Laboulbeniomycetes and their intimate association with their hosts.