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Abstract PremiseThe agaricomycete order Cantharellales contains approximately 1000 species of fungi characterized by diverse morphological forms, ecological guilds, and nutritional modes. Examples include coralloid lichens that form symbioses with unicellular green algae, bulbil‐forming lichenicolous species, corticioid free‐living fungi that degrade dead sources of organic carbon, pathogens that cause plant disease, orchid root endosymbionts, and ectomycorrhizal fungi including popular edible mushrooms. However, evolutionary relationships in the Cantharellales remain poorly understood due to conflicting estimates based on ribosomal DNA loci. MethodsWe constructed a five‐gene phylogeny of the Cantharellales using data from 301 specimens to evaluate family‐level relationships. We used penalized likelihood to estimate divergence times and ancestral state reconstruction to test the hypothesis of multiple independent origins of biotrophic ecologies in the order and whether those transitions are younger than the divergence times of associated plant or lichen hosts. ResultsFour monophyletic families were recovered with strong support: Botryobasidiaceae, Ceratobasidiaceae, Hydnaceae s.l., and Tulasnellaceae, with Hydnaceae containing the greatest species richness and morphological diversity. Our results suggest the Cantharellales diverged during the Carboniferous period with subsequent diversification following the Permian‐Triassic extinction. Ancestral state reconstruction supports a saprotrophic most recent common ancestor with at least three transitions to an ectomycorrhizal ecology, multiple transitions to a lichenicolous habit with one or more subsequent transitions to mutualistic nutritional modes, four transitions to an orchid mycorrhizal ecology, and two transitions to a lichenized lifestyle. ConclusionsThis study represents the first comprehensive examination of the evolution of form and function across this ecologically and morphologically diverse order of fungi. 

The National Ecological Observatory Network (NEON) is gathering select ecological and taxonomic data across 81 sites in the United States and Puerto Rico. Lichens are one of the organismal groups that NEON has not yet assessed across these sites. Here we sampled lichens at Ordway-Swisher Biological Station (OSBS), a NEON site in north central Florida, to provide a baseline survey of the commonly encountered macrolichens (foliose, fruticose, and squamulose lichens). Macrolichens represent a subset of observable lichens and are more commonly surveyed than crustose lichens. Seventy-four species of macrolichens were collected, including 25 occurrences that constitute new records for Putnam County, Florida. The lichen diversity at OSBS comprised approximately 30% of the macrolichen diversity known from the entire state of Florida. Fifty-four taxa are common in the state of Florida, 12 infrequent across the state, and eight are considered rare. Macrolichens were the seventh most species-rich taxonomic groups at OSBS and more diverse than the NEON focal groups of mammals and fish. Lastly, we suggest a theoretical roadmap for how lichenologists could work together with NEON to include lichens in future datasets. We hope that biologists focused on other key organismal groups will sample in NEON sites so that NEON data can be leveraged appropriately in future cross-taxon studies of biodiversity at the continental scale. 

Cistaceae are shrubs, subshrubs and herbs that often occur in stressful, fire-prone or disturbed environments and form ectomycorrhizal (ECM) associations with symbiotic fungi. Although some Cistaceae are long-lived shrubs that grow to significant size, others are herbaceous annuals or short-lived plants. Thus, Cistaceae are atypical ECM hosts that are fundamentally different in their biology from trees that are the more typically studied ECM hosts. The Mediterranean region is the center of diversity for Cistaceae and the ectomycorrhizal fungi associated with Cistaceae hosts have primarily been studied in Europe, North Africa, and the Middle East. Mediterranean Cistaceae often host diverse communities of ECM fungi, but they also act as hosts for some ECM fungi that putatively show host-specificity or strong host preference for Cistaceae (including species of Delastria, Hebeloma, Terfezia, and Tirmania). The ECM associations of Cistaceae in North America, however, remain highly understudied. Here we use fungal DNA metabarcoding to document the ectomycorrhizal fungal communities associated with Crocanthemum and Lechea (Cistaceae) in open, fire-prone sandhill habitats in north Florida. At each site we also sampled nearby Pinus to determine whether small, herbaceous Cistaceae have specialized ECM fungi or whether they share their ECM fungal community with nearby pines. The ECM communities of Florida Cistaceae are dominated by Cenococcum (Ascomycota) and Russula (Basidiomycota) species but were also significantly associated with Delastria, an understudied genus of mostly truffle-like Pezizales (Ascomycota). Although many Cistaceae ECM fungi were shared with neighboring pines, the ECM communities with Cistaceae were nonetheless significantly different than those of pines. 

Abstract BackgroundTruffles are subterranean fungal fruiting bodies that are highly prized for their culinary value. Cultivation of truffles was pioneered in Europe and has been successfully adapted in temperate regions throughout the globe. Truffle orchards have been established in North America since the 1980s, and while some are productive, there are still many challenges that must be overcome to develop a viable North American truffle industry. These challenges include extended delays between establishment and production, comparatively low yields, high spatial heterogeneity in yield distribution, and orchard contamination with lower-value truffle fungi. AimHere we review known requirements for truffle production including necessary environmental conditions, reproductive biology, and effective agronomic practices. ContentWe consider the potential limitations of importing exotic host-fungal associations into North America where there is already a rich community of competing ectomycorrhizal fungi, host pests and pathogens. We also describe the status of the North American truffle industry with respect to market potential, including production costs, pricing, and biological and socioeconomic risk factors. A critical aspect of modern trufficulture involves monitoring with genetic tools that supply information on identity, abundance and distribution of fungal symbionts, abundance of competitive and contaminating fungi, and insight into the interactions between fungal mating types that are fundamental to the formation of truffle primordia. ImplicationsCultivation of the ectomycorrhizal truffle symbiosis requires application of pragmatic agronomic practices, adopting rigorous quality control standards, and an understanding of fungal biology, microbiology, and molecular biology. Consequently, significant interdisciplinary collaboration is crucial to further develop the North American truffle industry. 

Pezizales are a diverse and economically important order of fungi. They are common in the environment, having epigeous form, such as morels and hypogeous, forms called truffles. The mature ascospores of most epigeous Pezizales are forcibly discharged through an opening at the ascus apex created with the lifting of the operculum, a lid-like structure specific to Pezizales. The axenic cultures of Pezizales fungi isolated from single ascospores are important for understanding the life cycle, development, ecology, and evolution of these fungi. However, obtaining single-spore isolates can be challenging, particularly for collections obtained in locations where sterile work environments are not available. In this paper, we introduce an accessible method for harvesting ascospores from fresh ascomata in the field and laboratory for obtaining single-spore isolates. Ascospores are harvested on the inside cover of Petri plate lids in the field, air dried, and stored. At a later date, single-spore isolates are axenically cultured through serial dilution and plating on antibiotic media. With this approach, we were able to harvest ascospores and obtain single-spore isolates from 12 saprotrophic and 2 ectomycorrhizal species belonging to six Pezizales families: Discinaceae, Morchellaceae, Pezizaceae, Pyronemataceae, Sarcosomataceae, and Sarcoscyphaceae. This method worked well for saprotrophic taxa (12 out of 19 species, 63%) and was even effective for a few ectomycorrhizal taxa (2 out of 13 species, 15%). This process was used to study the initial stages of spore germination and colony development in species across several Pezizales families. We found germination often commenced with the swelling of the spore, followed by the emergence of 1–8 germ tubes. This method is sufficiently straightforward that, provided with sterile Petri dishes, citizen scientists from distant locations could use this approach to capture spores and subsequently mail them with voucher specimens to a research laboratory for further study. The generated single-spore Pezizales isolates obtained through this method were used to generate high-quality genomic data. Isolates generated in this fashion can be used in manipulative experiments to better understand the biology, evolution, and ecogenomics of Pezizales. 

Presentation and illustration of a new species of the genus Paragalactinia, P. pseudomichelii, collected in Canada and the USA, based on morphological and molecular characters. An updated key to the genus Paragalactinia is also provided. 

The genus Rugosporella is proposed to accommodate Peziza atrovinosa in the modern classification scheme of the Pezizaceae. We used DNA sequences of ITS, LSU and RPB2 to resolve the phylogenetic placement of this taxon. The species occupies a distinct position within a large and diverse clade of hypogeous and epigeous taxa, all of which are either known to be or presumed to be ectomycorrhizal. Although no DNA sequences of this species have been identified from ectomycorrhizal roots, we provide isotopic data supporting its ectomycorrhizal lifestyle. Peziza atrovinosa is distinctive in its moderately large vinaceous brown apothecia with thick flesh and the relatively small ascospores that are ornamented with a high reticulum and that become yellow-brown at maturity. This species is found across eastern North America. 

Cortinarius watsoneae, a new species in subgenus Myxacium, sect. Myxacium, is described from pine and mixed pine and hardwood forests from the Gulf States region of North America. It is characterized by the young lamellae that are grayish violet to pale violet, and relatively large basidiospores in comparison to C. mucosus. The ITS sequence is distinct from other members of sect. Myxacium, with 97% similarity to the closest known species, C. collinitus and C. mucosus. The new species is named in honor of the late Geraldine Watson.