ISSN 1346-7565 Acta Phytotax. Geobot. 70 (3): 149–158 (2019) doi: 10.18942/apg.201901 Rediscovery of Liparis hostifolia (Orchidaceae) on Minami-iwo-to Island in the Bonin (Ogasawara) Archipelago, Japan, and its Identification Using Molecular Sequences from a Herbarium Specimen Collected more than 100 Years Ago 1,† 2,† 3 4 Koji TaKayama , Chie TsuTsumi , Dairo KawaguChi , hiDeToshi KaTo anD 2,* Tomohisa yuKawa 1Department of Botany, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan; 2 Department of Botany, National Museum of Nature and Science, 4-1-1 Amakubo, Tsukuba 305- 0005, Japan. *
[email protected] (author for correspondence); 3 Ogasawara Islands Branch Office, Tokyo Metropolitan Government, Nishimachi, Chichi-jima, Ogasawara-mura, Tokyo 100-2101, Japan; 4 Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami Osawa, Hachioji, Tokyo 192-0397, Japan. † These authors contributed equally to this work Liparis hostifolia (Orchidaceae) on Minami-iwo-to Island in the Bonin (Ogasawara) Archipelago was rediscovered for the first time in 79 years during a field survey in 2017. Its identity was confirmed by morphological comparison and DNA extractions from herbarium specimens collected between 1914 and 1938. Results from the molecular phylogenetic analyses demonstrated that L. hostifolia belongs to the L. makinoana complex. In comparison with other members of the L. makinoana complex, the broadly ovate labellum, short dormancy period, and flowering from November to March are unique characteristics of L. hostifolia. Results from the molecular phylogenetic analyses also suggested that L. hostifolia has had a long-isolated history in the Bonin Archipelago and probably migrated from temperate East Asia.