著者
Tao Fujiwara Junki Ogiso Sousuke Ishii Kei Togo Narumi Nakato Shunsuke Serizawa Yi-Shan Chao Hyoung-Tak Im Atsushi Ebihara Yasuyuki Watano
出版者
The Japanese Society for Plant Systematics
雑誌
Acta Phytotaxonomica et Geobotanica (ISSN:13467565)
巻号頁・発行日
vol.72, no.3, pp.205-226, 2021-10-31 (Released:2021-11-27)

Phegopteris decursivepinnata harbors diploid and tetraploid strains, forming a polyploid species complex together with P. koreana. Hybridization and polyploidization in the complex blur species boundaries, making it challenging to apply the proper taxonomic treatment. Ploidy determinations, phylogenetic analyses, and morphological investigations to elucidate the origins of the polyploid species and improve species classification for the P. decursivepinnata species complex are reported. Ploidy determinations and phylogenetic analyses revealed that diploid members of the complex were separated into two groups, a diploid P. decursivepinnata and a group consisting of Thelypteris itoana and a diploid P. koreana. The tetraploid P. decursivepinnata was shown to be an allotetraploid derived from hybridization between the two diploid groups. The samples of P. koreana revealed to be diploid suggested intraspecific cytotypic variation in P. koreana. The diploid P. koreana was genetically and morphologically indistinguishable from the diploid T. itoana. The diploid members of the complex previously treated as P. decursivepinnata are described as a new species, P. taiwaniana; and T. itoana is placed in synonymy under P. koreana.
著者
Hiroyuki Nakagawa Hidetoshi Nagamasu Shuichi Nemoto Shizuka Fuse Atsushi Ebihara Kohtaroh Shutoh
出版者
The Japanese Society for Plant Systematics
雑誌
Acta Phytotaxonomica et Geobotanica (ISSN:13467565)
巻号頁・発行日
vol.73, no.2, pp.151-157, 2022-06-30 (Released:2022-07-24)

Leymus komarovii (Roshev.) J. L. Yang & C. Yen (Triticeae, Poaceae) is a rare species in Japan, reported only twice from Hokkaido. In 2018, an additional specimen of L. komarovii was collected in Oketo-cho, Tokoro-gun, Hokkaido. Subsequent examination of specimens in Japanese herbaria revealed that its distribution range in Hokkaido was wider than previously known. Asperella longearistata (Hack.) Ohwi f. glabra Ko. Ito, described from Hokkaido, is reduced to synonym under L. komarovii and a lectotype for Hystrix sachalinensis Ohwi, another synonym of L. komarovii, is designated, superseding a previous lectotypification. A detailed description of L. komarovii based on Japanese materials and a key to the Japanese taxa of Leymus is provided.
著者
Katsuhiro Yoneoka Kiyotaka Hori Toshifumi Kataoka Tao Fujiwara Atsushi Ebihara Noriaki Murakami
出版者
The Japanese Society for Plant Systematics
雑誌
Acta Phytotaxonomica et Geobotanica (ISSN:13467565)
巻号頁・発行日
vol.74, no.1, pp.1-15, 2023-02-28 (Released:2023-03-15)

Haplopteris mediosora (Hayata) X. C. Zhang (Pteridaceae), a fern with linear simple fronds is widely distributed at high elevations from the Himalayas through China, the Philippines and Taiwan to Japan. In Japan, sporophytes of H. mediosora were recorded only from Azusa-shiraiwa, a mountain of Okuchichibu region, and have not been seen for over 50 years. The hypothesis that such rare species still persist as gametophytes was proven during this study when gametophytes were found on several mountains in the Oku-chichibu region. Phylogenetic analysis of rbcL sequences collected in this study demonstrated that the gametophytes, identified as H. mediosora, and sporophytes of H. mediosora formed a clade and were distinct from related species of Haplopteris. The gametophytes were also growing independently because of the absence of sporophytes. A comparison of the haplotypes of the matK and trnL-F regions showed that the gametophytes had two chloroplast DNA haplotypes. The polymorphisms may have been derived from ancestral sporophytes that were present in Japan during the glacial period. Despite the rarity of sporophytes in the area, the independent gametophytes occur in four distant localities in the Oku-chichibu mountains.
著者
Atsushi Ebihara Narumi Nakato Li-Yaung Kuo Hiroki Miyazaki Shunsuke Serizawa
出版者
The Japanese Society for Plant Systematics
雑誌
Acta Phytotaxonomica et Geobotanica (ISSN:13467565)
巻号頁・発行日
vol.70, no.1, pp.19-28, 2019-02-28 (Released:2019-03-09)

Acystopteris taiwaniana, formerly known only from Taiwan, is newly recorded in Japan (northern and central Honshu and Shikoku). Chromosome counts and DNA sequences (plastid rbcL and nuclear PgiC) suggested that it is an allotetraploid species originating from hybridization between diploid A. japonica and an unknown diploid species. Acystopteris taiwaniana differs from A. japonica in having glandular hairs on the indusia of the sori, paler stipes and rachises, wider angles of divergence of pinnae from the rachis and larger spores, although there overlaps in the variation. Triploid sterile hybrids between the two species occur occasionally at the periphery of populations of one of the parental species in Japan.
著者
Akiyo Naiki Takenori Yamamoto Aya Hasegawa Tao Fujiwara Katsuhiro Yoneoka Atsushi Ebihara
出版者
The Japanese Society for Plant Systematics
雑誌
Acta Phytotaxonomica et Geobotanica (ISSN:13467565)
巻号頁・発行日
vol.74, no.2, pp.131-133, 2023-07-31 (Released:2023-09-08)

Hymenophyllum pilosissimum C. Chr. (Hymenophyllaceae), recently discovered on Iriomote Island, is reported for the first time in Japan.