Sequestrate fungi from Patagonian Nothofagus forests: Cystangium (Russulaceae, Basidiomycota)

Loose Ends in the Cortinarius Phylogeny: Five New Myxotelamonoid Species Indicate a High Diversity of These Ectomycorrhizal Fungi with South American Nothofagaceae

This paper is a contribution to the current knowledge of taxonomy, ecology and distribution of South American Cortinarius (Pers.) Gray. Cortinarius is among the most widely distributed and species-rich basidiomycete genera occurring with South American Nothofagaceae and species are found in many distinct habitats, including shrublands and forests. Due to their ectomycorrhizal role, Cortinarius species are critical for nutrient cycling in forests, especially at higher latitudes. Some species have also been reported as edible fungi with high nutritional quality. Our aim is to unravel the taxonomy of selected Cortinarius belonging to phlegmacioid and myxotelamonioid species based on morphological and molecular data. After widely sampling Cortinarius specimens in Patagonian Nothofagaceae forests and comparing them to reference collections (including holotypes), we propose five new species of Cortinarius in this work. Phylogenetic analyses of concatenated rDNA ITS-LSU and RPB1 sequences failed to place these new species into known Cortinarius sections or lineages. These findings highlight our knowledge gaps regarding the fungal diversity of South American Nothofagaceae forests. Due to the high diversity of endemic Patagonian taxa, it is clear that the South American Cortinarius diversity needs to be discovered and described in order to understand the evolutionary history of Cortinarius on a global scale.

Four new species of sequestrate Inocybe from Chilean Nothofagaceae forests

Sequestrate fungi have enclosed hypogeous, subhypogeous, or epigeous basidiomes and have lost the ability to actively discharge their spores. They can be distinguished as gasteroid (basidiome fully enclosed with a loculated hymenophore) or secotioid (basidiome with some agaricoid or pileate-stipitate features, but the lamellae are misshapen and unexposed or mostly unexposed at maturity). There are only four reports of sequestrate taxa within the ectomycorrhizal family Inocybaceae, three from Australia and one from western North America. Recent field work in Nothofagaceae forests in the Chilean coastal range revealed novel sequestrate forms of Inocybe. We examined specimens using a combination of morphological and molecular data from nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and portions of nuc 28S rDNA (28S) and the gene encoding the second largest subunit of RNA polymerase II (rpb2). Here, we describe four new sequestrate Inocybe species, I. ranunculiformis, I. anfractuosa, I. illariae, and I. nahuelbutensis. Results of our phylogenetic analysis resolved the four new species as distinct species-level clades with strong support, suggesting that these fungi have convergently evolved sequestrate forms independently. The species described here were all placed along with members of the "smooth-spored temperate austral clade," which includes almost exclusively Australasian and South American species of Inocybe.

A phylogenetic and taxonomic revision of sequestrate Russulaceae in Mediterranean and temperate Europe

A comprehensive morphological and genetic study of type material and new collections of sequestrate Russulales species formerly belonging to the genera Arcangeliella, Elasmomyces, Gymnomyces, Hydnangium, Hymenogaster, Macowanites, Martellia, Secotium and Zelleromyces is here undertaken, for the purpose of providing a complete taxonomical revision of sequestrate Russulaceae species in the Mediterranean and temperate regions of Europe. As a result, seven distinct taxa in the genus Lactarius and 18 in the genus Russula are identified. Six of them are new species: L. populicola, L. subgiennensis, R. bavarica, R. candidissima, R. hobartiae and R. mediterraneensis, and seven represent new combinations: L. josserandii (≡ Zelleromyces josserandii), L. soehneri (≡ Hydnangium soehneri), R. candida (≡ Hydnangium candidum), R. cerea (≡ Hydnangium cereum), R. messapica var. messapicoides (≡ Macowanites messapicoides), R. meridionalis (≡ Zelleromyces meridionalis) and R. neuhoffii (≡ Hydnangium neuhoffii). Twenty-two of the 25 taxa are illustrated, while descriptions, microscopy images, as well as extensive information on the ecology, chorology and phylogeny for all taxa are provided. A key is further included to facilitate their identification.

Phylogeny, biogeography and taxonomic re-assessment of Multifurca (Russulaceae, Russulales) using three-locus data

Multifurca is a small genus newly established to accommodate lactarioid and russuloid species with some characters reminiscent of corticoid members of Russulaceae. It shows an amphi-pacific distribution with strong preference for the tropical zone of the Northern Hemisphere and thus has particular significance for biogeographical study. Using worldwide samples and three loci (ITS, 28S rDNA and rpb2), we demonstrated that Multifurca is split into two highly supported major clades that are here recognized at the subgeneric level: subg. Furcata subg. nov. exclusively includes lactarioid species, while subg. Multifurca includes species with a russuloid habit. Using phylogenetic species recognition and comparison of genetic distances we recognize five new and six previously described species, almost double the known number of species before this study. Molecular dating using a Bayesian method suggested that Multifurca originated in early Paleocene and diversified in the Eocene. The most recent interspecific divergences occurred both in Asia and America, roughly at the same time around the Pliocene. Ancestral area reconstruction and comparisons of genetic distances and morphology suggested an early divergence within Australasia or tropical Asia. From the early Miocene to Pliocene, multiple dispersals/migrations to Australasia and North America by island hopping or land bridge likely happened. Vicariance at the late Tertiary might be the most likely mechanism accounting for the eastern Asia-southeastern North America and Australasia-tropical Asia disjunct distributions. The shared polymorphisms in the ITS alignment, numerous degenerated base pairs in the rpb2 sequences and weak conflict between the ITS and LSU genealogies of M. subg. Furcata suggest recent speciation. Host specificity of Multifurca species or species pairs is relatively low. Host shifts are believed to have aided establishment in new territories during the dispersals and migrations.