Invasive alien species are serious threats to the biota of the Ogasawara Islands, and Morus australis is one of them. To clarify the invasion routes and the genetic composition of the founding populations, plant samples were collected from 32 populations of M. australis from Japan, including 12 from the Ogas- awara Islands, for population genetic analyses using 14 microsatellite markers. The UPGMA dendro- gram based on Nei’s genetic distance, Principal Coordinate Analysis based on pairwise F _ST values, and Bayesian Clustering using STRUCTURE software indicated that the populations of M. australis in the Ogasawara Islands are genetically similar to those in the Ryukyu Islands, but clearly differentiated from those in the Izu Islands and mainland of Japan. The level of genetic diversity in the Ogasawara Islands (A _R = 4.24; H _E = 0.60) was similar to that in the Ryukyu Islands (A _R = 4.70; H _E = 0.66). The findings from this study strongly suggested that M. australis plants now in the Ogasawara Islands are descendants of those introduced from the Ryukyu Islands; the numbers of transplanted individuals from the Ryukyu Islands were large. Such high genetic diversity may have enhanced the invasiveness of M. australis in the Ogasawara Islands.

抄録全体を表示

Flowering and dispersal phenology, characteristics of fruits, seed shape, and seed and embryo sizes were studied in orchids in the warm temperate zone of Japan. Anemochorous potential was estimated based on the ratio of seed length to embryo length. The data obtained were compared among different life forms: epiphyte, saprophyte (myco-heterotroph), summer green terrestrial and evergreen terrestrial or- chids. The epiphytes, which had the smallest seeds, had the poorest dispersibility. On the other hand, the saprophytes, which had elongated seeds, had excellent dispersibility. Seed size and dispersibility of ter- restrial orchids ranged between those of epiphytes and saprophytes. Most epiphytes had hygroscopic trichomes, which contributed to the release of the seeds from capsule. It was clarified that seed morphol- ogy and dispersal mechanisms in orchids were closely related to their life form.

抄録全体を表示

A new species of Sagittaria (Alismataceae), S. siamaginashi, characterized by a cylindrical branch with numerous tubercles in each leaf axil, is described from Thailand and Myanmar. The scapes and inflores- cences were not seen in nature, but gibberellin-treated individuals flowered under cultivation. In floral morphology, S. siamaginashi is similar to the Chinese endemic, S. lichuanensis. A phylogenetic study based on DNA sequences of the internal transcribed spacer and chloroplast rpl16 intron, psbA–trnH spacer and trnC–petN (ycf6) spacer regions showed that S. siamaginashi and S. lichuanensis were sister taxa. A key to the taxa of Sagittaria in E and SE Asia is also provided.

抄録全体を表示

Ribes fujisanense S. Sakag. & Mit. Oishi (Grossulariaceae), an obligate epiphytic gooseberry, is de- scribed here for the first time. It is narrowly endemic in the cool-temperate forests of Mt. Fuji and adja- cent areas of central Japan. Ribes fujisanense is morphologically most similar to R. ambiguum Maxim., but is distinguished by the reddish apex of the calyx lobes, branchlets armed with prickles, petioles with long glandular trichomes and more deeply lobed leaf blades. Phylogenetic analysis based on genome- wide markers showed that the two species are considerably divergent, even though R. fujisanense fully overlaps the distribution of the wide-ranging R. ambiguum, indicating that they are biologically isolated species.

抄録全体を表示

Species-level identification of aquatic plants, such as duckweeds (Lemnaceae), can be challenging due to reduced morphological features and high phenotypic plasticity. A taxonomic study of sect. Uninerves of the genus Lemna in Japan based on morphological observations and DNA analyses is reported. Two non- indigenous species, L. minuta and L. valdiviana, were confirmed to occur in Japan. Excessively small, enigmatic plants of Lemna apparently specialized to grow in spring-fed waterbodies was determined to be a form of L. minuta. It could not be concluded whether the miniature Lemna represents an ecotype adapted to cool water or an example of phenotypic variation under low temperature conditions.

抄録全体を表示

Ardisia imbakensis Utteridge & Julius (Primulaceae-Myrsinoideae), a new species of Ardisia subgenus Pyrgus, is described and illustrated from the Malaysian state of Sabah. Remarkable for the massive, elliptic leaves and the lateral reproductive branches with ovate to oblong foliose bracts, the new species is endemic to the Imbak Canyon Conservation Area in northern Borneo.

抄録全体を表示

The taxonomic identity of Garcinia bonii Pit. (Clusiaceae) in Vietnam was re-evaluated based on the original description and type materials and reclassified in sect. Oxycarpus, not in sect. Hebradendron (previous treatment). Garcinia bokorensis H. Toyama & Yahara of Cambodia is proposed as a new syn- onym of G. bonii based on a morphological comparison. A lectotype of G. bonii is designated and an updated distribution map is provided.

抄録全体を表示

The parentage of the Potamogeton hybrids P. ×nomotoensis Kadono & T. Noguchi and P. ×yamaga- taensis Kadono & Wiegleb (Potamogetonaceae) was studied by analyzing the plastid-encoded rbcL gene and nuclear-encoded internal transcribed spacer (ITS) from the hybrids and putative parents. The results showed P. ×nomotoensis to be a hybrid between P. natans and P. maackianus and P. ×yamagataensis a hybrid between P. natans and P. oxyphyllus. The latter is the first documentation of a hybrid between diploid and tetraploid species in Japan.

抄録全体を表示

Acanthophippium sylhetense Lindl. (Orchidaceae) is reported as a new record for the Vietnamese flora. Taxonomic notes and a key to the species of Acanthophippium in Vietnam are also provided.

抄録全体を表示

Twelve polymorphic EST-SSR markers were developed and characterized for Tephroseris furusei (Kitam.) B. Nord., an endangered species endemic to limestone habitats in central Japan, and related spe- cies. In the two T. furusei populations, the total numbers of alleles for each locus ranged from 5 to 16 (average = 8.75). The observed (H_O) and expected (H_E) heterozygosities ranged from 0.33 to 0.76 (average = 0.58) and 0.50 to 0.89 (average = 0.75), respectively. The inbreeding coefficient (fixation index, F_IS) ranged from 0.14 to 0.50 (average = 0.24) and five loci deviated significantly from Hardy–Weinberg equi- librium. The versatility of the markers was evaluated for three congenerics: T. flammea (Turcz. ex DC.) Holub subsp. flammea, T. integrifolia (L.) Holub subsp. kirilowii (Turcz. ex DC.), and T. pierotii (Miq.) Holub. All of the EST-SSR markers were transferrable among them.

抄録全体を表示

Tadashi Yamashiro, Asuka Yamashiro, Michiyuki Maruoka, Tomiki Kobayashi and Masayuki Maki. 2021. Genetic Structure of a Rare Interspecific Hybrid of Vincetoxicum atratum and V. pycnostelma (Apocynaceae–Asclepiadoideae). Acta Phytotaxonomica et Geobotanica 72 (3): 227–239.

“oblong–oblanceolate leaves” (p. 227, right, l. 7) should be replaced by “oblong–lanceolate leaves”.

抄録全体を表示

Kana Watanabe-Toma, Jin Murata and Tetsuo Ohi-Toma. 2021. Aristolochia kaempferi var. laevipes (Aristolochiaceae): A New Variety from the Ise-Shima and Owari Regions, Japan. Acta Phytotaxo- nomica et Geobotanica 72 (3): 281–287.

“(fig. 3-6, 10, 11 & 12) in Ohi-Toma et al. 2014)” (p. 281, left, l. 20) should be replaced by “(fig. 3-6, 10, 11 & 12 in Ohi-Toma et al. 2014)”. “Bote 2 (Geography).” (p. 285, left, l. 15) should be replaced by “Note 2 (Geography).”

抄録全体を表示