Type Studies on Basidiomycetes. I

Systematic revision of the Roseinae clade of Russula, with a focus on eastern North American taxa

The Roseinae clade is a lineage of the genus Russula primarily composed of species of Russula subsect. Roseinae. Species in this morphologically distinct clade possess a white to pale cream spore print, mild taste, positive reaction to sulfovanillin, and primordial hyphae with acid-resistant crystals in the pileipellis. Here, we present a morphological and phylogenetic assessment that distinguishes seven eastern North American species of the core Roseinae lineage and a new subsection, Russula subsection Albidinae, to accommodate members of the Albida clade. We assign the previously described species R. peckii, R. rubellipes, and R. pseudopeckii to three species-level clades, and three other species, R. cardinalis, R. cordata, and R. rheubarbarina, are described as new. Comparative morphological analyses reveal differences in the conformation of terminal elements in the pileipellis, spore size, hymenial cystidia contents, and pigmentation on the stipe surface as key features to recognize species in the group. Based on the analysis of publicly available data, we recognize a potential total of nine temperate North American species within R. subsect. Roseinae, in addition to four from Central America, two from Europe, and 14 from Asia.

Paxilloboletus gen. nov., a new lamellate bolete genus from tropical Africa

This study presents Paxilloboletus gen. nov., a new lamellate bolete genus represented by two tropical African species, Paxilloboletus africanus sp. nov. and Paxilloboletus latisporus sp. nov. Although the new taxa strongly resemble Paxillus (Paxillaceae), they lack clamp connections and form a separate generic clade within the Boletaceae phylogeny. The new species are lookalikes, morphologically only separable by their spore morphology. Descriptions and illustrations of the new genus and new species are given, as well as comments on ecology, distribution, and morphological differences with other gilled Boletaceae.

Taxonomic revision of Russula subsection Amoeninae from South Korea

RussulasubsectionAmoeninae is morphologically defined by a dry velvety pileus surface, a complete absence of cystidia with heteromorphous contents in all tissues, and spores without amyloid suprahilar spot. Thirty-four species within subsection Amoeninae have been published worldwide. Although most Russula species in South Korea have been assigned European or North American names, recent molecular studies have shown that Russula species from different continents are not conspecific. Therefore, the present study aims to: 1) define which species of RussulasubsectionAmoeninae occur on each continent using molecular phylogenetic analyses; 2) revise the taxonomy of Korean Amoeninae. The phylogenetic analyses using the internal transcribed spacer (ITS) and multilocus sequences showed that subsection Amoeninae is monophyletic within subgenus HeterophyllidiaesectionHeterophyllae. A total of 21 RussulasubsectionAmoeninae species were confirmed from Asia, Australia, Europe, North America, and Central America, and species from different continents formed separate clades. Three species were recognized from South Korea and were clearly separated from the European and North American species. These species are R.bella, also reported from Japan, a new species described herein, Russulaorientipurpurea, and a new species undescribed due to insufficient material.

Clitopilus lampangensis (Agaricales, Entolomataceae), a new species from northern Thailand

A new species of agaricomycetes, Clitopiluslampangensis, is described based on collections from northern Thailand. This species was distinguished from previously described Clitopilus species by its pale yellow to grayish yellow pileus with the presence of wider caulocystidia. Molecular phylogenetic analyses, based on the data of the internal transcribed spacers (ITS) and the large subunit (LSU) of the nuclear ribosomal DNA, and the second largest subunit of RNA polymerase II (rbp2) genes, also support the finding that C.lampangensis is distinct from other species within the genus Clitopilus. A full description, color photographs, illustrations and a phylogenetic tree showing the position of C.lampangensis are provided.