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Xerampelinae is a subsection composed of species of ectomycorrhizal fungi belonging to the hyperdiverse and cosmopolitan genus Russula (Russulales). Species of Xerampelinae are recognized by their fishy or shrimp odor, browning context, and a green reaction to iron sulfate. However, species delimitation has traditionally relied on morphology and analysis of limited molecular data. Prior taxonomic work in Xerampelinae has led to the description of as many as 59 taxa in Europe and 19 in North America. Here we provide the first multilocus phylogeny of European and North American members based on two nrDNA loci and two protein-coding genes. The resulting phylogeny supports the recognition of 17 species-rank Xerampelinae clades; however, higher species richness (~23) is suggested by a more inclusive nuclear rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS barcode) analysis. Phylogenetic and morphological analyses support three new species with restricted geographic distributions: R. lapponica, R. neopascua , and R. olympiana . We confirm that the European species R. subrubens is present in North America and the North American species R. serissima (previously known as R. favrei ) is present in Europe. Most other Xerampelinae appear restricted to either North America or Eurasia, which indicates a high degree of regional endemism; this includes R. xerampelina , a name widely applied to North American taxa, but a species restricted to Eurasia.

As a recent group mainly defined by molecular data the genus Lactifluus is in need of further study to provide insight into the morphological and molecular variation within the genus, species limits and relationships. Phylogenetic analyses of nuc rDNA ITS1-5.8S-ITS2 (ITS), D1 and D2 domains of nuc 28S rDNA (28S), and part of the second largest subunit of the RNA polymerase II (rpb2) (6-7 region) sequences of 28 samples from southern China revealed three new lineages of Lactifluus. Two of them are nested in a major clade that includes the type of Lactifluus and here is treated as two new sections: L. sect. Ambicystidiati and L. sect. Tenuicystidiati. Lactifluus ambicystidiatus, described here as a new species (= sect. Ambicystidiati), has both lamprocystidia and macrocystidia in the hymenium, a unique combination of features within Russulaceae. Furthermore, only remnants of lactiferous hyphae are present in L. ambicystidiatus and our results suggest that the ability to form a lactiferous system has been lost in this lineage. Lactifluus sect. Tenuicystidiati forms a strongly supported monophyletic group as a sister lineage to L. sect. Lactifluus. We recognize it based on the thin-walled macrocystidia and smaller ellipsoid spores with an incomplete reticulum compared with L. sect. Lactifluus. The former placement of L. tenuicystidiatus in the African L. sect. Pseudogymnocarpi is not supported. Using genealogical concordance we recognize five phylogenetic species within L. sect. Tenuicystidiati and describe two of these as new, L. subpruinosus and L. tropicosinicus. The third lineage, represented by L. leoninus, forms a sister group to L. subg. Lactariopsis sensu stricto. The three lineages provide further evidence for morphological features in Lactifluus being homoplasious. Some sections and species complexes are likely to be composed of more species and merit further investigations. Subtropical-tropical Asia is likely a key region for additional sampling., (© 2015 by The Mycological Society of America.)

This contribution to the genus Cantharellus in North America deals with the smaller, reddish pink species from the Gulf of Mexico states and eastern United States. C. texensis sp. nov. is presented as a new southern lookalike of C. cinnabarinus. The morphological species concepts are supported by newly generated molecular sequence data from the protein coding gene tef1. Similarities to C. persicinus, a third pinkish taxon, are discussed. The very different microscopic features for the three taxa are illustrated in detail. C. cinnabarinus is neotypified. C. minor forma intensissima is considered to be possibly unrelated not only to the discussed taxa in this paper but also to typical C. minor.

Russula parvovirescens sp. nov. is described from the eastern United States. It is a rather common species that previously was mistaken for a small R. virescens or a green form of R. crustosa. The large and characteristic extremities that compose the pileipellis allow easy identification with the microscope or even with a good hand lens. The new species is described here, illustrated in detail and compared with R. virescens and R. crustosa.

Detailed illustrated descriptions are given for Russula panamae sp.nov, Russula aucarum, R. puiggarii and R. venezueliana, all of which are reported for the first time from Panamá. For Russula venezueliana and R. aucarum, it is also the first record since their original description. Taxonomy, systematic position, and related species are discussed for each species. Russula ochrostraminea is probably a synonym of R. venezueliana and section Delicoarchaeae is considered a possible synonym of subsection Lactarioideae or of section Metachromaticae.