論文

© 2017 The Mycological Society of Japan To compare morphological characters and phylogenetic placement between Japanese and European Russula, 32 specimens of 12 species were collected from Japanese subalpine forests and Northern Europe. Several sequences of nrDNA ITS region (ITS) of these Russula species were obtained. High homological similarities were shown between ITS sequences of several Russula samples collected from Japanese subalpine forests, Europe and North America. These facts show distribution of the same Russula species among these areas. From morphological observations and phylogenetic analyses, two same Russula species, R. velenovskyi, and R. decolorans are found in Japan, Europe and North America. Of these, R. velenovskyi collected from Mt. Fuji, Mt. Nyukasa and Mt. Tateshina in mountainous area of central Honshu is reported as a new Japanese record.

© 2018 Magnolia Press. The life cycle of the aecial stage of a rust fungus found on Elaeagnus umbellata var. rotundifolia in Chiba, Japan was clarified by inoculations. This rust fungus was morphologically identified as Puccinia velutina (anamorph: Aecidium elaeagni) alternating between Carex lenta and Elaeagnus species. This plant is a new host for this rust fungus. However, the current International Code of Nomenclature (ICN, Melbourne 2012) has abolished the distinction between “anamorph” and “teleomorph” names, and we propose a new name, P. neovelutina as a replaced name for A. elaeagni, because Puccinia elaeagni is a preoccupied available name. Its epitype specimen is designated.

© 2018 Magnolia Press. Tricholosporum haitangshanum sp. nov. is described as a new species from China, based on morphological and molecular data. It is morphologically characterized by a yellowish ochre pileus, cruciate basidiospores and ampullaceous cystidia. Phylogenetic analyses based on the nuc rDNA internal transcribed spacer (ITS) region supports that it belongs to Tricholosporum. Comparing it with phenotypically similar and molecular phylogenetically allied taxa concluded that it is a new species in Tricholosporum.

© 2018 International Mycological Association. Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.

© 2018 The Mycological Society of Japan A fungus parasitic on a fern, Dennstaedtia wilfordii (Dennstaedtiaceae), was found at the foothill of Mt. Fuji, Yamanashi Prefecture, Japan. Its hyphae spread within host mesophyll cells and through intercellular spaces, forming coiled haustoria in the epidermal and mesophyll cells. The hyphae emerged either through stomata or by disrupting epidermal cell junctions. The hyphae spreading over the abaxial leaf surface generated one-septate, thin-walled basidia. All the morphological features observed were characteristic of the genus Herpobasidium. The species identification of the fungus as H. filicinum by morphology was supported by molecular phylogenetic analyses of the D1/D2 region of the large subunit rRNA gene.