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)

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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.