The Ophiostomatales was erected in 1980. Since that time, several of the genera have been redefined and others have been described. There are currently 14 accepted genera in the Order. They include species that are the causal agents of plant and human diseases and common associates of insects such as bark beetles. Well known examples include the Dutch elm disease fungi and the causal agents of sporotrichosis in humans and animals. The taxonomy of the Ophiostomatales was confused for many years, mainly due to the convergent evolution of morphological characters used to delimit unrelated fungal taxa. The emergence of DNA-based methods has resolved much of this confusion. However, the delineation of some genera and the placement of various species and smaller lineages remains inconclusive. In this study we reconsidered the generic boundaries within the Ophiostomatales. A phylogenomic framework constructed from genome-wide sequence data for 31 species representing the major genera in the Order was used as a guide to delineate genera. This framework also informed our choice of the best markers from the currently most commonly used gene regions for taxonomic studies of these fungi. DNA was amplified and sequenced for more than 200 species, representing all lineages in the Order. We constructed phylogenetic trees based on the different gene regions and assembled a concatenated data set utilising a suite of phylogenetic analyses. The results supported and confirmed the delineation of nine of the 14 currently accepted genera, i.e.Aureovirgo, Ceratocystiopsis, Esteya, Fragosphaeria, Graphilbum, Hawksworthiomyces, Ophiostoma, Raffaelea and Sporothrix. The two most recently described genera, Chrysosphaeria and Intubia, were not included in the multi-locus analyses. This was due to their high sequence divergence, which was shown to result in ambiguous taxonomic placement, even though the results of phylogenomic analysis supported their inclusion in the Ophiostomatales. In addition to the currently accepted genera in the Ophiostomatales, well-supported lineages emerged that were distinct from those genera. These are described as novel genera. Two lineages included the type species ofGrosmannia andDryadomyces and these genera are thus reinstated and their circumscriptions redefined. The descriptions of all genera in the Ophiostomatales were standardised and refined where this was required and 39 new combinations have been provided for species in the newly emerging genera and one new combination has been provided for Sporothrix. The placement of Afroraffaelea could not be confirmed using the available data and the genus has been treated as incertae sedis in the Ophiostomatales. Paleoambrosia was not included in this study, due to the absence of living material available for this monotypic fossil genus. Overall, this study has provided the most comprehensive and robust phylogenies currently possible for the Ophiostomatales. It has also clarified several unresolved One Fungus-One Name nomenclatural issues relevant to the Order.

Citrullus colocynthis grows in the sandy desert soil of the Arabian Peninsula with limited access to water, aside from occasional precipitation or dew. Understanding its ability to produce water-filled fruit and nutrient-rich seeds despite the harsh environment, can be useful for agricultural applications. However, information regarding the microbiome of C. colocynthis is lacking. We hypothesized that C. colocynthis associates with bacteria that aid its survival, like what has been observed in other desert plants. Here, we used 16S rRNA gene data to gain insight into the microbiome of C. colocynthis to identify its associated bacteria. In total, 9818 and 6983 OTUs were generated from root, soil, and leaf samples combined. Overall, bulk soils had the highest alpha diversity, followed by rhizosphere and root zone soils. Furthermore, C. colocynthis is associated with known plant-growth-promoting bacteria (including Acidobacteria, Bacterioidetes, and Actinobacteria), and interestingly a class of non-photosynthetic Cyanobacteria (Melainabacteria) that is more abundant on the inside and outside of the root surface than control samples, suggesting its involvement in the rhizophagy process. This study will provide a foundation for functional studies to further understand how C. colocynthis-microbes interactions help them grow in the desert, paving the path for possible agricultural applications.

Species of Raffaelea (Ophiostomatales: Ascomycota) are obligate symbionts of ambrosia beetles, some of which pose a substantial threat to forest trees. Leucaena leucocephala is a small mimosoid tree species that is considered as an invasive weed in most of its introduced range globally. During a field expedition on the French island of Réunion, dying L. leucocephala trees were observed. Samples were taken from these trees and isolations made from symptomatic wood tissues that included beetle tunnels, but in the absence of the beetles themselves. Multiple isolates of a fungus resembling a Raffaelea species were obtained from the discoloured wood associated with the beetle tunnels. To determine their identity, microscopic examination was performed and DNA sequences for three gene regions (ITS, LSU, TUB) were obtained. Phylogenetic analyses based on these gene regions revealed that the isolates represent a new species of Raffaelea, described here as R. borbonica sp. nov. A pathogenicity test was conducted with the fungus, which was shown to cause lesions on the inoculated seedlings, but with a low level of aggressiveness.

At a routine health check of a female peregrine falcon, 23 trematodes preliminary identified as Prosthogonimus sp. were removed from the bursa of Fabricius. Based on morphological and molecular examination, a new species, Prosthogonimus falconis, was described. The pear-shaped flukes were 4.3–6.9 mm long, with greatest width posterior to testes. Tegumental spines measuring between 17 and 21 μm long covered the whole body. Length and width ratio of oral to ventral suckers were 1:1.3. Extracaecal, multifollicular vitelline glands commenced prior to acetabulum and terminated posterior to testes. Eggs in the distal uterus measured 21 × 12 μm. Molecular analysis of internal transcribed spacer 2, cytochrome c oxidase subunit 1 and NADH dehydrogenase subunit 1 gene regions revealed that the new species described here is phylogenetically closest to Prosthogonimus cuneatus and Prosthogonimus pellucidus clusters.

Anaerobic gut fungi of the class Neocallimastigomycetes are of great importance for herbivorous animals. Their immediate colonization and mechanical breakdown of plant particles pave the way for highly efficient enzymatic fermentation of complex plant polysaccharides. Neocallimastigomycetes are found in a variety of herbivores, yet so far studies almost exclusively investigated domestic or captive animals. Here, the occurrence and diversity of Neocallimastigomycetes in two different populations of sympatric, wild African forest elephants and forest buffaloes were determined. In both hosts together, a total of 16 species-equivalent Operational Taxonomic Units (OTUs) (0.05 cut-off level) were generated. Buffaloes harboured four and elephants five anaerobic fungi genera or genus-equivalent taxa, respectively, with four genera occurring in both hosts. In elephants the majority of gut fungi group within a cluster of yet unknown Neocallimastigomycetes. Similarly, some anaerobic fungi found in buffaloes form a genus-equivalent cluster with likewise undescribed gut fungi. Sequences grouping in these two clusters could potentially qualify as representatives of new anaerobic fungi genera. Further, three sequences have not yet been encountered in any study and cannot be assigned to any genus or genus-equivalent Neocallimastigomycetes taxon. Whether these sequences also represent putative new lineages needs further investigation.