著者

Kenji Suetsugu Tian-Chuan Hsu

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.3, pp.177-182, 2023-10-31 (Released:2023-11-04)

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This is the first report of Taeniophyllum complanatum from Yakushima Island, Amami-Oshima Island, and Okinawa Island, Ryukyu Islands, Japan. The species is rare and was previously considered to be endemic to Taiwan. It is distinguishable from T. aphyllum by its strongly flattened roots, minutely papillate inflorescences and the shape of the fully developed fruit.

著者

Kenji Suetsugu Shun K. Hirota Koji Yonekura Atsushi Abe Yoshihisa Suyama Tian-Chuan Hsu

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.121-129, 2023-07-31 (Released:2023-09-08)

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The present study documents the first record of Thrixspermum annamense (Orchidaceae) from Iriomote Island, Ryukyu Islands, Japan, expanding its known distribution beyond Vietnam, Thailand, Taiwan, China, and Malaysia. While the morphologically similar taxon T. fantasticum is present on the island, it can be distinguished from T. fantasticum by its somewhat narrower and more rigid leaves, slightly narrower sepals, densely hairy midlobe of the lip, and the absence of two horn-like appendages at the base of the midlobe. A detailed morphological analysis also revealed that the plants discovered on Iriomote Island closely resemble T. annamense from Taiwan but show consistent morphological and molecular distinctions from T. annamense from Vietnam, the type locality. Despite those differences, the high similarity in gross morphology and most lip structures of the plants from Japan, Taiwan, and Vietnam indicates that they all belong to T. annamense at the species level. Consequently, considering the genetic and morphological differences, we propose resurrecting the name T. devolianum, originally described from Taiwan, and reclassifying it as a variety of T. annamense (T. annamense var. devolianum). A neotype for T. devolianum is also designated.

著者

Shinya Hieda Konomi Ota Kisa Nagamine Hiroki Kobayashi Naohiko Noma

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.47-51, 2023-02-28 (Released:2023-03-15)

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Endozoochorous dispersal of the invasive alien aquatic plant Ludwigia grandiflora subsp. hexapetala through waterfowl in Lake Biwa, Japan, is reported. Germination of seeds collected from the feces of waterfowl in Yabase, southern Lake Biwa proved them to be viable. It is necessary to be vigilant against the sudden appearance of L. grandiflora subsp. hexapetala in water systems where it is absent and to monitor its dispersal by waterfowl.

著者

Toshio Katsuki

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.69, no.2, pp.119-126, 2018 (Released:2018-06-30)

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A new species, Cerasus kumanoensis T. Katsuki (Rosaceae), sp. nov., is described from the southern Kii Peninsula, Japan. It is similar to C. jamasakura var. jamasakura and C. leveilleana because the corymbose inflorescences and extended peduncle are identical in these three taxa. However, C. kumanoensis is distinguished by several morphological and phenological characteristics, an earlier flowering period, narrowly ovate and smaller leaf blade (4–8 cm long, 1.8–3.6 cm wide) and glabrous petiole and pedicel.

著者

Hiroshi Takahashi Tomohisa Yukawa Masayuki Maki

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.265-274, 2021-10-31 (Released:2021-11-27)

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Petrosavia amamiensis (Petrosaviaceae) is described as a new species from Amami-Oshima Island, Kagoshima Prefecture, Japan. The plants were previously identified as P. sakuraii. The flowers of P. amamiensis are autonomously self-pollinated at the beginning of anthesis, while those of P. sakuraii are self-pollinating at a later stage of anthesis. Petrosavia amamiensis has a shorter aerial stem, shorter internodes, more densely flowered inflorescence and smaller seeds than P. sakuraii. Moreover plastid and nuclear DNA differ greatly between P. amamiensis and P. sakuraii.

著者

Kenji Suetsugu

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.3, pp.211-217, 2022-11-30 (Released:2022-12-15)

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Gastrodia (Orchidaceae) is a species-rich, achlorophyllous genus containing more than 100 species. Recently, several species of Gastrodia with only closed, self-pollinating, cleistogamous flowers were discovered in Japan and Taiwan. Here, an additional taxon of Gastrodia with completely cleistogamous flowers from a lowland evergreen forest on Yakushima, Japan, is described as G. takeshimensis Suetsugu var. shirataniensis Suetsugu. It is most similar to G. takeshimensis var. takeshimensis, but is distinguishable by its peloric labellum and column with a prominent ventral appendage. The assignment of taxonomic rank to a peloric, completely cleistogamous orchid, is discussed. Comparison between G. takeshimensis var. shirataniensis and other taxa of Gastrodia revealed that G. qingyunshanensis is conspecific with G. clausa. The ecological significance of the column appendage in G. takeshimensis var. shirataniensis and G. clausa is also discussed.

著者

Shotaro Midorikawa Kohtaroh Shutoh Takashi Shiga

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.71, no.1, pp.55-63, 2020-02-29 (Released:2020-03-17)

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Najas minor and N. oguraensis (Hydrocharitaceae) are annual submerged plants and are difficult to distinguish owing to their similarities. While the number of anther locules and the size of the leaf epidermal cells differ between the two species, the anther locules are often difficult to observe on herbarium specimens and the effectiveness of using the size of the leaf epidermal cells as a taxonomic key character is currently unknown. We examined the size of the leaf epidermal cells in living plants and in dried specimens to evaluate the effectiveness of this feature in species identification. We first identified the two species by observing the anther locule number and then compared the size of the leaf cells in fixed and dried specimens. To identify plant fragments, we examined differences in epidermal cell length and width depending on the position of the cells within the plant. The length and width significantly differed in both fixed and dried leaves between the species. In particular, the epidermal cells of N. oguraensis ( > 160 μm) were about twice as long as those of N. minor regardless of leaf position. We therefore concluded that cell size, especially length, is a valid method for identifying the species in both fresh and dried condition. This method is effective where precise identifications are necessary, such as in floristic surveys and environmental assessments.

著者

Kenji Suetsugu Hirokazu Fukunaga

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.69, no.1, pp.63-67, 2018 (Released:2018-03-02)

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Here we describe a new variety of the mycoheterotrophic genus Lecanorchis, L. triloba J. J. Sm. var. clausa Suetsugu & Fukunaga, discovered during a botanical survey in Okinawa Island, Ryukyu Islands, Japan. The new variety resembles Lecanorchis triloba var. triloba due to its densely flowered rachis and small fruits. However, the new variety differs in that it has complete cleistogamous flowers and a nonrecurved and narrowly triangular midlobe of the lip.

著者

Kenji Suetsugu Takaomi Sugimoto

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.69, no.1, pp.69-74, 2018 (Released:2018-03-02)

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We report three new localities of the mycoheterotrophic plant Sciaphila corniculata (Triuridaceae) from Ishigaki Island, Ryukyu Islands, Japan. Previously, S. corniculata was reported only from Kolombangara Island (Solomon Islands), Waigeo Island (New Guinea) and Obi and Aru islands (the Moluccas). We also update a description of its morphology, in particular on stylar characteristics based on new materials. A key to the Japanese species of Sciaphila based on total flower and stylar characteristics is also provided for easy identification of these rare mycoheterotrophic plants.

著者

Kenji Suetsugu Phetlasy Souladeth Shuichiro Tagane Tetsukazu Yahara

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.69, no.2, pp.139-141, 2018 (Released:2018-06-30)

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A new locality of Lecanorchis taiwaniana from Nam Ha National Protected Area, Luang Namtha Province, northern Laos is reported and a description of the species based on the Laos material is provided. Lecanorchis taiwaniana was known previously only from Japan and Taiwan. Considering that species of Lecanorchis are easily overlooked in the wild due to their short flowering season and dwarf habit, it is possible that L. taiwaniana is more widely distributed.

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.

著者

Satoshi Aoki Tetsuo Ohi-Toma Jin Murata

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.3, pp.159-172, 2019-10-31 (Released:2019-11-28)

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The classification of Oxalis subsect. Oxalis (Oxalidaceae) is revised based on phylogenetic, cytological and morphological evidence. For the flora of Japan, one new species and one new variety are described, and five new combinations are proposed. The new species, O. nipponica, resembles O. griffithii, but is distinguished by its unique phylogeny, larger genome and distribution. Oxalis nipponica is subdivided into two subspecies, nipponica and kantoensis based on phylogeny and fruit length. Subsp. kantoensis is further divided into two varieties based on ploidy level, length of the fruit and seeds and habitat. While diploids correspond to var. kantoensis, the tetraploids correspond to the newly described var. alpigena. Variety alpigena resembles O. acetosella and has been confused with it. Fourteen taxa, including one hybrid, are recognized in subsect. Oxalis.

著者

Kenji Suetsugu Jing-Zhi Lin Tian-Chuan Hsu Hiroshi Hayakawa

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.71, no.2, pp.177-184, 2020-06-30 (Released:2020-07-31)

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Two closely related species, Spiranthes sinensis and S. australis (Orchidaceae), have often been distinguished based on the presence or absence of hairs in their inflorescence and on the stems and ovaries: the stems and ovaries of S. australis are generally pubescent, whereas those of S. sinensis are reported to be glabrous. Although S. australis has not been documented to occur in Taiwan, we found a population of Spiranthes with slightly pubescent stems and ovaries at Tahanshan, southern Taiwan. Because the slightly pubescent plants may represent an undocumented extension of the distribution of S. australis, we attempted to identity the slightly pubescent plants by sequencing the ITS and trnL–F intergenic spacer regions. We also compared the lip and column morphology, which have diagnostic characteristics in Spiranthes, and the molecular and morphological data from S. australis, S. sinensis, their close relative, S. hongkongensis, and the unknown plants. The molecular analysis revealed the slightly pubescent plants to be heterozygous for the ITS sequences from S. australis and S. sinensis or from S. hongkongensis and S. sinensis, whereas the trnL–F intergenic spacer region was identical to that of S. sinensis. While we could not completely exclude the possibility that the unknown plants were hybrids between S. hongkongensis and S. sinensis based on the molecular data, we concluded that they were hybrids between the pubescent S. australis and the glabrous S. sinensis (Taiwan type) based on the lip and column morphology.

著者

Yasuro Kadono Tomoyoshi Noda Kazumasa Tsubota Kohtaroh Shutoh Takashi Shiga

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.2, pp.129-134, 2019-06-30 (Released:2019-07-10)

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An alien member of the Utricularia (Lentibulariaceae) discovered in Japan is currently assigned to U. inflata, a native of North America. However, some morphological traits differ between the plants in Japan and U. inflata, including the apex of the floral spur and filament of the stamens. The alien plants are completely sterile, while U. inflata is capable of seed production. DNA analysis revealed that the chloroplast DNA sequences of the alien also differ from those of U. inflata in four regions. We provisionally determine the alien plants to be U. cf. platensis, a South American species with which it shares many traits.

著者

Koji Takayama Chie Tsutsumi Dairo Kawaguchi Hidetoshi Kato Tomohisa Yukawa

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.3, pp.149-158, 2019-10-31 (Released:2019-11-28)

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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.

著者

Tetsukazu Yahara Mutsuko Nakajima

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.69, no.3, pp.203-208, 2018-10-31 (Released:2018-11-02)

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Gastrodia albida T. C. Hsu & C. M. Kuo is reported from Yaku Island, Kagoshima Prefecture, Japan, as a new record of this species to Japan. Traits of G. albida are described and illustrated based on specimens collected on Yaku Island. This species has a unique combination of characters, such as only partly united lateral sepals, curved perianth tube and white triangular lip. The population on Yaku Island differs from the population at the type locality in Taiwan in having widely opening lateral sepals and a flat-topped disk of the lip and epichile slightly 2-ridged along the margin.

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)

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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

Norikazu Okabe Tetsukazu Yahara Shuichiro Tagane Chika Mitsuyuki Ayumi Matsuo Takanori Sasaki Etsuko Moritsuka Kengo Fuse Usun Shimizu-Kaya Julia Anak Sang Runi Sylvester Pungga Yoshihisa Suyama

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.1, pp.43-59, 2021-02-28 (Released:2021-03-21)

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A new species, Actinodaphne lambirensis Tagane, Yahara & N. Okabe (Lauraceae) from Lambir Hills National Park, Miri District, Sarawak, Malaysia, is described and illustrated. It is characterized by glabrous twigs and leaves, small lamina (4.3–9.2 × 1.7–2.8 cm), and long fruiting peduncles. Because only fruiting specimens were available, the position of A. lambirensis was determined by the phylogenetic trees based on 22 species of Actinodaphne, including the type species of the genus, A. pruinosa Nees, and 11 species of Neolitsea from Southeast Asia using multiplexed inter-simple sequence repeats genotyping by sequencing (MIG-seq). Additionally, a phylogenetic tree was constructed using internal transcribed spacer (ITS) sequences for 36 species of Actinodaphne and 40 species of Neolitsea that include our MIGseq samples and additional species for which ITS sequences were determined in previous studies. Both the MIG-seq tree and ITS tree supported A. lambirensis as belonging with Actinodaphne.

著者

Kohtaroh Shutoh Mitsuru Usuba Hiroki Yamagishi Yushi Fujita Takashi Shiga

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.71, no.1, pp.33-44, 2020-02-29 (Released:2020-03-17)

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Potamogeton ×angustifolius (P. gramineus × P. lucens) was newly recorded in Japan from a pond in Tsugaru-shi, Aomori Prefecture. The hybrid nothospecies was identified based on morphological observations and measurements, molecular analyses using cloned nuclear adhA gene and chloroplast rpl20–rps12 intergenic spacer, and pollen viability. The putative hybrid had morphological traits intermediate between P. gramineus and P. lucens, nuclear haplotypes matching those of the two parental lineages, and lower pollen viability than P. lucens (not compared with P. gramineus). The maternal lineage of the hybrid was presumed to be P. gramineus, based on chloroplast sequences. The hybrid characteristically shows well-branched stems in the upper part of shoots, as in P. gramineus, and both clearly petiolate and sessile submerged leaves with distinctive netted venation. Similar plants were collected in the 1980s from a ditch near the pond, suggesting that the hybrid may have been present for more than 30 years in this area.

著者

Kenji Suetsugu Tian-Chuan Hsu

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.39-45, 2023-02-28 (Released:2023-03-15)

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The taxonomic status of Taeniophyllum aphyllum (Makino) Makino, described from Kochi, Japan, is reevaluated. It has often been treated as a synonym of T. glandulosum Blume from Java, Indonesia, but is distinguishable from T. glandulosum by the pubescence of the inflorescence rachis, the arrangement of the flowers, inflorescence length, and shape of the fully developed fruit. It is therefore proposed that T. aphyllum is recognized as a distinct species. A lectotype for T. aphyllum is also proposed.