Hydnum atlanticum, a new species from Eastern North America.

A new species of Hydnum subgenus Rufescentia is described based on collections made in Canada (New Brunswick, Newfoundland and Labrador) and the USA (New York). The new species is found in conifer dominated forests (e.g. Abies, Picea) and occurs in bryophyte-covered (Sphagnum, Bazzania) soil. It differs from the ecologically similar H. quebecense in the duller brown colors of the basidiomes, the smaller basidiospores and the basidia predominantly with three or four sterigmata. Phylogenetic analysis of the ITS region place H. subconnatum and H. oregonense as the closest relatives of H. atlanticum, but these taxa differ in the larger basidiospores, number of sterigmata per basidium, caespitose growth and/or geographic distribution. Citation: Justo A, Hood AW, Swenie RA, Matheny PB (2023). Hydnum atlanticum, a new species from Eastern North America. Fungal Systematics and Evolution 11: 63-70. doi: 10.3114/fuse.2023.11.05.

A phylogeny for North American Mallocybe (Inocybaceae) and taxonomic revision of eastern North American taxa.

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. Citation: Matheny PB, Kudzma LV, Graddy MG, Mardini SM, Noffsinger CR, Swenie RA, Walker NC, Campagna SR, Halling R, Lebeuf R, Kuo M, Lewis DP, Smith ME, Tabassum M, Trudell SA, Vauras J (2023). A phylogeny for North American Mallocybe (Inocybaceae) and taxonomic revision of eastern North American taxa. Fungal Systematics and Evolution 12: 153-201. doi: 10.3114/fuse.2023.12.09.

Four new nodulose-spored species of Inocybe (Agaricales) from West Africa.

We describe four new nodulose-spored species of Inocybe from tropical regions of Africa: I. beninensis, I. flavipes, I. fuscobrunnea and I. pallidiangulata. The new species are recognised based on morphological data and phylogenetic analyses of ITS, 28S and RPB2 sequences. Phylogenetic analyses indicated that I. flavipes and I. beninensis are part of a subclade leading to the I. calida group. Inocybe fuscobrunnea appears sister to the I. asterospora group. Inocybe pallidiangulata is nested within a clade of mainly tropical species from South Asia, Africa, and South America, close to the subclade of I. lilacinosquamosa and I. ayangannae from Guyana. Complete descriptions and illustrations, including photographs and line drawings, and a key to nodulose-spored taxa of tropical African species of Inocybe are provided. Citation: Aïgnon HL, Jabeen S, Verbeken A, Matheny PB, Yorou NS, Ryberg M (2022). Four new nodulose-spored species of Inocybe (Agaricales) from West Africa. Fungal Systematics and Evolution 10: 1-18. doi: 10.3114/fuse.2022.10.01.

Scaling up: examining the macroecology of ectomycorrhizal fungi.

Ectomycorrhizal (ECM) fungi play major ecological roles in temperate and tropical ecosystems. Although the richness of ECM fungal communities and the factors controlling their structure have been documented at local spatial scales, how they vary at larger spatial scales remains unclear. In this issue of Molecular Ecology, Tedersoo et al. (2012) present the results of a meta-analysis of ECM fungal community structure that sheds important new light on global-scale patterns. Using data from 69 study systems and 6021 fungal species, the researchers found that ECM fungal richness does not fit the classic latitudinal diversity gradient in which species richness peaks at lower latitudes. Instead, richness of ECM fungal communities has a unimodal relationship with latitude that peaks in temperate zones. Intriguingly, this conclusion suggests the mechanisms driving ECM fungal community richness may differ from those of many other organisms, including their plant hosts. Future research will be key to determine the robustness of this pattern and to examine the processes that generate and maintain global-scale gradients of ECM fungal richness.

Lower level relationships in the mushroom genus Cortinarius (Basidiomycota, Agaricales): a comparison of RPB1, RPB2, and ITS phylogenies.

We sampled and analyzed approximately 2900bp across the three loci from 54 taxa belonging to a taxonomically difficult group of Cortinarius subgenus Phlegmacium. The combined analyses of ITS and variable regions of RPB1 and RPB2 greatly increase the resolution and nodal support for phylogenies of these closely related species belonging to clades that until now have proven very difficult to resolve with the ribosomal markers, nLSU and ITS. We present the first study of the utility of variable regions of the genes encoding the two largest subunits of RNA polymerase II (RPB1 and RPB2) for inferring the phylogeny of mushroom-forming fungi in combination with and compared to the widely used ribosomal marker ITS. The studied region of RPB1 contains an intron of the size and variability of ITS along with many variable positions in coding regions. Though almost entirely coding, the studied region of RPB2 is more variable than ITS. Both RNA polymerase II genes were alignable across all taxa. Our results indicate that several sections of Cortinarius need redefinition, and that several taxa treated at subspecific and varietal level should be treated at specific level. We suggest a new section for the two species, C. caesiocortinatus and C. prasinocyaneus, which constitute a well-supported separate lineage. We speculate that sequence information from RNA polymerase II genes have the potential for resolving phylogenetic problems at several levels of the diverse and taxonomically very challenging genus Cortinarius.