Despite the recent molecular systematic analyses of the Entolomataceae (Agaricales, Basidiomycota), a robust classification of genera supported by morphological and phylogenetic evidence remains unresolved for this cosmopolitan family of pink-spored fungi. Here, a phylogenetic analysis for one of the two major clades (Rhodocybe-Clitopilus) was conducted using three nuclear protein-coding gene regions, the mitochondrial ATP synthase subunit 6 (atp6), the nuclear RNA polymerase subunit II (rpb2) and the nuclear translation elongation factor subunit 1-α (tef1). Five monophyletic groups are resolved with strong statistical support and a set of morphological features for delineation of genera is presented. In the revised classification proposed here, Clitopilus is retained, Rhodocybe is emended, two genera previously accepted as synonyms of Rhodocybe (Clitopilopsis and Rhodophana) are resurrected and Clitocella is described as new.

Due to their submerged and cryptic lifestyle, the vast majority of fungal species are difficult to observe and describe morphologically, and many remain known to science only from sequences detected in environmental samples. The lack of practices to delimit and name most fungal species is a staggering limitation to communication and interpretation of ecology and evolution in kingdom Fungi. Here, we use environmental sequence data as taxonomical evidence and combine phylogenetic and ecological data to generate and test species hypotheses in the class Archaeorhizomycetes (Taphrinomycotina, Ascomycota). Based on environmental amplicon sequencing from a well-studied Swedish pine forest podzol soil, we generate 68 distinct species hypotheses of Archaeorhizomycetes, of which two correspond to the only described species in the class. Nine of the species hypotheses represent 78% of the sequenced Archaeorhizomycetes community, and are supported by long read data that form the backbone for delimiting species hypothesis based on phylogenetic branch lengths. Soil fungal communities are shaped by environmental filtering and competitive exclusion so that closely related species are less likely to co-occur in a niche if adaptive traits are evolutionarily conserved. In soil profiles, distinct vertical horizons represent a testable niche dimension, and we found significantly differential distribution across samples for a well-supported pair of sister species hypotheses. Based on the combination of phylogenetic and ecological evidence, we identify two novel species for which we provide molecular diagnostics and propose names. While environmental sequences cannot be automatically translated to species, they can be used to generate phylogenetically distinct species hypotheses that can be further tested using sequences as ecological evidence. We conclude that in the case of abundantly and frequently observed species, environmental sequences can support species recognition in the absences of physical specimens, while rare taxa remain uncaptured at our sampling and sequencing intensity.

In boreal systems, soil profiles typically consist of distinct stratified horizons, with organic layers at the surface overlying deeper mineral horizons providing microhabitat variation along a depth gradient, and vertical stratification of fungal communities along such soil profiles is commonly observed. We studied fungal community structure in a coastal pine forest along a gradient of decreasing influence from the coast. In this system, the vertical stratification pattern of soil microhabitats (defined here as organic, mineral with roots and mineral without roots: O, MR and MN, respectively) is non-uniform; organic horizons are sometimes buried under drifting sand dunes. Our results show that soil microhabitats are distinct with respect to physiochemical characteristics, community composition and OTU richness. While community composition was partly related to depth and distance from the coastal forest edge, microhabitat appeared to have the strongest influence. A closer inspection of the OTUs with the highest relative sequence abundance within each microhabitat revealed that microhabitats support functionally distinct fungal communities with respect to trophic mode and growth morphology. These results suggest that in coastal pine forests, variation in soil microhabitats contributes to the high fungal diversity found belowground and may play an important role in optimizing nutrient cycling.

Long amplicon metabarcoding has opened the door for phylogenetic analysis of the largely unknown communities of microeukaryotes in soil. Here, we amplified and sequenced the ITS and LSU regions of the rDNA operon (around 1500 bp) from grassland soils using PacBio SMRT sequencing. We tested how three different methods for generation of operational taxonomic units (OTUs) effected estimated richness and identified taxa, and how well large‐scale ecological patterns associated with shifting environmental conditions were recovered in data from the three methods. The field site at Kungsängen Nature Reserve has drawn frequent visitors since Linnaeus's time, and its species rich vegetation includes the largest population of Fritillaria meleagris in Sweden. To test the effect of different OTU generation methods, we sampled soils across an abrupt moisture transition that divides the meadow community into a Carex acuta dominated plant community with low species richness in the wetter part, which is visually distinct from the mesic‐dry part that has a species rich grass‐dominated plant community including a high frequency of F. meleagris. We used the moisture and plant community transition as a framework to investigate how detected belowground microeukaryotic community composition was influenced by OTU generation methods. Soil communities in both moisture regimes were dominated by protists, a large fraction of which were taxonomically assigned to Ciliophora (Alveolata) while 30%–40% of all reads were assigned to kingdom Fungi. Ecological patterns were consistently recovered irrespective of OTU generation method used. However, different methods strongly affect richness estimates and the taxonomic and phylogenetic resolution of the characterized community with implications for how well members of the microeukaryotic communities can be recognized in the data.

Forests and woodlands in the West African Guineo-Sudanian transition zone contain many tree species that form symbiotic interactions with ectomycorrhizal (ECM) fungi. These fungi facilitate plant growth by increasing nutrient and water uptake and include many fruiting body-forming fungi, including some edible mushrooms. Despite their importance for ecosystem functioning and anthropogenic use, diversity and distribution of ECM fungi is severely under-documented in West Africa. We conducted a broad regional sampling across five West African countries using soil eDNA to characterize the ECM as well as the total soil fungal community in gallery forests and savanna woodlands dominated by ECM host tree species. We subsequently sequenced the entire ITS region and much of the LSU region to infer a phylogeny for all detected soil fungal species. Utilizing a long read sequencing approach allows for higher taxonomic resolution by using the full ITS region, while the highly conserved LSU gene allows for a more accurate higher-level assignment of species hypotheses, including species without ITS-based taxonomy assignments. We detect no overall difference in species richness between gallery forests and woodlands. However, additional gallery forest plots and more samples per plot would have been needed to firmly conclude this pattern. Based on both abundance and richness, species from the families Russulaceae and Inocybaceae dominate the ECM fungal soil communities across both vegetation types. The community structure of both total soil fungi and ECM fungi was significantly influenced by vegetation types and showed strong correlation within plots. However, we found no significant difference in fungal community structure between samples collected adjacent to different host tree species within each plot. We conclude that within plots, the fungal community is structured more by the overall ECM host plant community than by the species of the individual host tree that each sample was collected from.

-Three new Inocephalus species with cuboid spores are described from central New South Wales and northern Queensland, Australia. Inocephalus plicatus is diagnosed by its yellow pileus becoming plicate-striate and yellowish orange when mature, pungent odor, bitter taste, and pseudocystidia on all lamellar surfaces. Inocephalus hypipamee is differentiated by its brown umbonate pileus, white lamellae and stipe, obclavate cheilocystidia, subisodiametric basidiospores and clampless hyphae. Inocephalus parvisporus possesses small basidiospores and a Leptonia-like stature.

-Descriptions and illustrations are provided for five Leptonia species. Three species are new to science: Leptonia boardinghousensis possesses unusual basidiomes colours, L. ambigua has subisodiametric basidiospores that atypically have obscure angles at the apex and a lignicolous habit, and L. omphalinoides is distinguished by its lignicolous omphalinoid tiny basidiomes. Two species were previously reported: L. poliopus from Europe and L. umbraphila comb. nov from the Seychelles.

Multiple collections of a new member of the Entolomataceae were found in W National Park of Niger during a survey of macrofungi. This new species with a dark reddish brown scaly pileus surface and a yellow stipe belongs in the genus Rhodophana of the Rhodocybe-Clitopilus clade in the Entolomataceae. Using a three-gene analysis of the phylogenetic position of Rhodophana flavipes it is most closely related to the recently described Rhodophana squamulosa from India and is a sister taxon to Rhodophana nitellina and R. melleopallens. Micromorphological examination of the type of Rhodocybe fibulata, another African species with a scaly cap, confirms that it belongs in Rhodophana, thus a new combination Rhodophana fibulata is proposed.