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A multigene phylogenetic assessment of North American species of Mallocybe is presented based on analyses of rpb1, rpb2, ITS, and 28S rDNA nucleotide data. This framework enables a systematic revision of the genus for 16 eastern North American species and captures taxonomic and phylogenetic diversity in a global context. A grade of two unusual and poorly known North American species stems from the most recent common ancestor of the genus that gives rise to three core subgroups named here as clades Unicolores, Nothosperma, and Mallocybe. The grade of taxa includes the poorly known Lepista praevillosa from Florida and a new species from the southern Appalachians, M. montana, both of which appear to be narrow-range endemics. Clade Nothosperma is characterized by Australian and New Zealand species, whereas clade Unicolores is composed of six species from eastern North America and East Asia. Clade Mallocybe is dominated by numerous north temperate taxa and constitutes the sister group to clade Nothosperma. These major clades are distinguished by a combination of phylogeny, morphology, geographic distribution, and ecology. In addition, four North American species are described as new: M. leucothrix, M. luteobasis, M. montana, and M. tomentella. Several names originating in North America, long ignored or misunderstood in the literature, are revitalized and established by type comparisons and modern reference material collected from or near type localities. In addition, 11 species were subjected to mass spectrometry muscarine assays, none of which contained detectable amounts of muscarine except for two: M. sabulosa and M. praevillosa. This confirms a diffuse phylogenetic distribution of muscarine within the genus. Taxonomic descriptions are presented for 16 species, several synonymies proposed, and four new combinations made. A key to species of eastern North American Mallocybe is presented, along with illustrations of important diagnostic features. [ABSTRACT FROM AUTHOR]

As currently delineated, Hygrophorus sect. Olivaceoumbrini is a polyphyletic assembly within subg. Colorati, encompassing glutinous and pigmented taxa. According to available literature, between a dozen and twenty species may belong in the section, mostly represented in continental and boreal forests of Europe and North America. However, the limited phylogenetic and biogeographic coverage of the genus does not presently allow for a reliable assessment of its taxonomic boundaries, nor does it provide a complete picture of species diversity within sect. Olivaceoumbrini. In an ongoing effort to confer an evolutionary backbone to Hygrophorus systematics, we assembled and analysed a dataset comprising 268 intercontinental sequences, including holotypes of 7 taxa previously not positioned phylogenetically, and enriched with collections from largely unexplored Mediterranean and Anatolian ecosystems. Overall, 30 clades are identified within 5 distinct lineages, including 11 species putatively new to science. Seven of these are formally described here as H. agathosmoides, H. albofloccosus, H. canadensis, H. limosus, H. marcocontui, H. pinophilus and H. pustulatoides spp. nov. This enriched coverage of section Olivaceoumbrini s.lat. calls for a re-evaluation of its natural boundaries into a core monophyletic clade, including H. olivaceoalbus and five closely related lookalikes, as well as the assignment of the section rank to the four remaining lineages: sect. Fuscocinerei sect. nov., sect. Limacini sect. nov., sect. Nudolidi sect. nov. and sect. Tephroleuci, respectively. We also stabilize the usage of six historical names, H. glutinifer, H. hyacinthinus, H. mesotephrus, H. olivaceoalbus, H. pustulatus and H. tephroleucus, through designation of two neotypes, three lectotypes and four epitypes. [ABSTRACT FROM AUTHOR]

Several members of the genus Peziza sensu stricto occur at the edge of melting snow. These nivicolous species have been widely reported in the Northern Hemisphere and are also known from Australia and New Zealand. We have used 16 specimens from North America and Australia to study morphology and to perform DNA sequencing. In sequence analyses, we have used ITS1 and ITS2 (internal transcribed spacers), 28S, RPB2 (RNA polymerase II gene), and two genes new to these studies, GAPDH (glyceraldehyde-3-phosphate dehydrogenase) and HSP90 (heat shock protein 90). Although not all regions are available for all samples, we have recognized the following species: Peziza heimii, P. nivalis , and P. nivis . Phylogenetic analyses were done using ITS alone; combined ITS1-5.8S-ITS2, 28S, and RPB2 ; ITS, and 28S, RPB2, GAPDH , and HSP90 . Even with this augmented set of genes and despite their widespread occurrence in North America, Europe, Australia, and New Zealand, we have not definitively distinguished species within this group. To assess these results, pairwise homoplasy index (PHI) analysis was employed. This showed evidence of recombination among the samples of P. nivalis and further supports the view of P. nivalis as a monophyletic cosmopolitan species. As part of this study, we also examined the variation in ITS copies in P. echinospora , for which a genome is available.