論文

Crepidotus crocophyllus, one of the most common species of the genus Crepidotus (Basidiomycota, Fungi)in Japan, were morphologically and phylogenetically reexamined based on the materials collected from Choshi, Chiba Prefecture, Central Japan. Morphologically, Japanese C. crocophyllus were well match with previous descriptions of the present species based on European and American materials. To reveal the phylogenetic placement of Japanese specimens of C. crocophyllus, molecular phylogenetic analysis of the present species were conducted. By maximum parsimony analysis of nuclear rRNA ITS region, materials of C. crocophyllus collected from Japan (Choshi, Chiba) and North America (USA) were placed within well-supported, different clades each other. The present analysis revealed for the first time that Japanese and North American specimens of C. crocophyllus are polyphyletic, and a taxonomic revision of the species tentatively identified as C. crocophyllus is therefore needed.

The activity concentration of 131I, 134Cs and 137Cs radionuclides in lichens was traced one and a half months after the Fukushima nuclear accident. The samples were collected in Tsukuba City, which is located c. 170 km south of the Fukushima Daiichi nuclear power plant (NPP). The activity concentrations differed depending on species and habitat. For example, the maximum activity concentration of 137Cs was 22596 Bq kg-1 dry weight in Physcia orientalis (collected from the trunk of Zelkova serrata on 30 June 2011), and 1928 Bq kg-1 in Hyperphyscia crocata (from the trunk of Quercus myrsinaefolia collected on 8 March 2012). The activity concentration of 137Cs in Dirinaria applanata and Phaeophyscia spinellosa growing on vertical habitats decreased by c. 50% within a year, indicating radionuclides might have been washed off by rain. The radionuclides were apparently derived from the Fukushima NPP accident because: 1) one specimen collected at the same place one year before the accident did not contain radionuclides, 2) high activity concentrations of radionuclides were detected after the accident, 3) 131I, which has a short half-life of 8 days, was detected one and a half months after the accident, and 4) the ratio of 134Cs/137Cs in lichens was 0·90-0·98 on 26 April 2011, which is consistent with the values reported for radiocesium from the Fukushima NPP accident. Copyright © British Lichen Society 2013.

日本新産のチャツムタケ属菌，Gymnopilus decipiens （ヤケノヒメチャツムタケ），について，北海道で採集された標本に基づき，形態的特徴の記載と図を添えて報告した．北海道産 G. decipiens は火山性ガスを含む高温の水蒸気が噴出する噴気孔周辺に発生し，子実体は小型で温和な味であることが特徴である．分子系統解析の結果， 日本産標本の核 rDNA の ITS 領域は，ロシア（ ヤクーツク） 産 G. decipiens のものと完全に一致する塩基配列を有し，本菌がシベリアから北海道の亜寒帯にかけて連続的に分布することが示された．