Dermoloma is traditionally known as a small genus of agarics classified in the family Tricholomataceae. This study implemented a multilocus phylogeny of six DNA regions to recognize phylogenetic species within the genus. The species concept is reinforced by observations of well-defined morphological characters enhanced by long term sampling effort in Europe and North America. Thirty European Dermoloma species are described, including 16 new species from Europe and three from North American. These species are classified into two subgenera morphologically distinguished by spores with positive or negative amyloid reaction. A new genus Neodermoloma is introduced for the Dermoloma-like species N. campestre. Localized or continental-scale species endemicity was confirmed based on studied material, but more inclusive phylogenetic clustering supported a mixture of North American species among the European clades. Of the 22 names validly published from Europe prior to this study, 11 could be assigned to well-defined Dermoloma species recognized here. Of the remaining 11 names, two were considered representing Dermoloma species not recorded since their description, and nine were established as later synonyms of other species. Morphological studies of Dermoloma are challenging due to the relatively low number of characters suitable for identification of species. The majority of morphological characters showed continuous variation with high overlap throughout the genus. For this reason, species identification requires an awareness of morphological variability within species, and multiple distinguishing characters need to be combined, and furthermore, often a barcode sequence is needed for a certain identification. Stable isotope analysis in Dermoloma of δ¹³C and δ¹⁵N revealed an ecological signature similar to known CHEGD fungi, i.e. Clavariaceae and Hygrocybe s.l. This indicates that Dermoloma species are biotrophic but neither ectomycorrhizal nor saprotrophic and may form mutualistic root endophytic associations with vascular plants.

Trichodermais a cosmopolitan genus with diverse lifestyles and nutritional modes, including mycotrophy, saprophytism, and endophytism. Previous research has reported greater metabolic gene repertoires in endophytic fungal species compared to closely-related non-endophytes. However, the extent of this ecological trend and its underlying mechanisms are unclear. Some endophytic fungi may also be mycotrophs and have one or more mycoparasitism mechanisms. Mycotrophic endophytes are prominent in certain genera likeTrichoderma, therefore, the mechanisms that enable these fungi to colonize both living plants and fungi may be the result of expanded metabolic gene repertoires. Our objective was to determine what, if any, genomic features are overrepresented in endophytic fungi genomes in order to undercover the genomic underpinning of the fungal endophytic lifestyle. Here we compared metabolic gene cluster and mycoparasitism gene diversity across a dataset of thirty-eightTrichodermagenomes representing the full breadth of environmentalTrichoderma’s diverse lifestyles and nutritional modes. We generated four newTrichoderma endophyticumgenomes to improve the sampling of endophytic isolates from this genus. As predicted, endophyticTrichodermagenomes contained, on average, more total biosynthetic and degradative gene clusters than non-endophytic isolates, suggesting that the ability to create/modify a diversity of metabolites potential is beneficial or necessary to the endophytic fungi. Still, once the phylogenetic signal was taken in consideration, no particular class of metabolic gene cluster was independently associated with theTrichodermaendophytic lifestyle. Several mycoparasitism genes, but no chitinase genes, were associated with endophyticTrichodermagenomes. Most genomic differences betweenTrichodermalifestyles and nutritional modes are difficult to disentangle from phylogenetic divergences among species, suggesting thatTrichodermagenomes maybe particularly well-equipped for lifestyle plasticity. We also consider the role of endophytism in diversifying secondary metabolism after identifying the horizontal transfer of the ergot alkaloid gene cluster toTrichoderma.

In the present paper, we revise the taxonomy of the Auriculariales having pedunculate (stalked) basidia. In total, sixteen new species from Europe, East Asia, North and South America, and tropical Africa are described. They are classified among the genera Hydrophana, Mycostilla, Myxarium, Protoacia, Protohydnum, and Protomerulius. In addition, the generic affiliation of eleven extant species is re-established based on phylogenetic and/or morphological evidence. A new genus, Elmericium, is introduced to accommodate a crust-like fungus, E. alabastrinum, from East Asia; phylogenetic data place it in the vicinity of the anatomically similar poroid genera Elmerina and Protodaedalea (Auriculariaceae). The generic description of Protohydnum is amended; in its current scope, the genus encompasses several species formerly assigned to Bourdotia, Ductifera, and Exidiopsis. Available environmental data point to a wider distribution of some Protomerulius spp. and greater species diversity in the genus than currently surmised from physical fungal samples.

We studied the taxonomy of Pluteus podospileus and similar species using morphological and molecular (nrITS, TEF1-α) data, including a detailed study of the type collections of P. inflatus var. alneus, Pluteus minutissimus f. major, and P. granulatus var. tenellus. Within the P. podospileus complex, we phylogenetically confirmed six species in Europe, five in Asia, and eight in North America. Based on our results, we recognize P. seticeps as a separate species occurring in North America, while P. podospileus is limited to Eurasia. We describe six new species and a new variety: P. absconditus, P. fuscodiscus, P. gausapatus, P. inexpectatus, P. millsii, and P. notabilis and its variety, P. notabilis var. insignis. We elevate Pluteus seticeps var. cystidiosus to species rank as Pluteus cystidiosus. Based on the holotype of P. inflatus var. alneus, collections of P. inflatus identified by Velenovský, and several modern collections, we resurrect the name P. inflatus. Based on molecular analyses of syntypes of Pluteus minutissimus f. major and a holotype of Pluteus granulatus var. tenellus, we synonymize them under P. inflatus. We also increase our knowledge about the morphology and distribution of P. cutefractus.

Chromosera cyanophylla was initially described from Europe and, when it was named type of the genus, was thought to be distributed throughout Europe and North America. Molecular phylogenies revealed that Chromosera “cyanophylla” from eastern and western North America represent two separate species and that neither is conspecific with European C. cyanophylla nor with the more recently described C. ambigua. Here we describe a new species from western North America as Chromosera loreleiae. We resurrect the species Peck described from eastern North America as Agaricus lilacifolius by recombining it in Chromosera and describe a new lilac variety lacking yellow pigments. The range of C. cyanophylla s.s. across eastern Eurasia including China is confirmed. Chromosera citrinopallida, described from Washington state, USA, comprised one clade in Washington that we infer is C. citrinopallida s.s. and a separate circumarctic clade distributed in Scandinavia, Iceland and Alaska.