Hygrophorus yukishiro sp nov., a new vernal edible mushroom from Nagano Prefecture, Japan

A novel basidiomycetous species, Hygrophorus yukishiro, is described from Japan. The basidiomata of this fungus have been referred to as yuki-shiro, yuki-take, and yuki-wari, and used as an edible mushroom in the central region of Nagano, Japan. Hygrophorus yukishiro fruits in the early spring season under oak-dominated stands. Morphological and phylogenetic analyses of the internal transcribed spacer region of the nuclear ribosomal RNA gene indicated that H. yukishiro is a sister species of H. arbustivus and belongs to section Hygrophorus, subsect. Fulventes. Hygrophorus yukishiro is similar in its external morphology and fruiting phenology to H. roseobrunneus, H. leucophaeo-ilicis, and H. roseodiscoideus, but differs in the color and texture of its pileus surface and microscopic characteristics. (C) 2018 The Mycological Society of Japan. Published by Elsevier B.V. All rights reserved.