Silene kiusiana (Caryophyllaceae) is an endangered perennial herb of semi-natural grasslands in Japan and Korea. To elucidate the genetic status of S. kiusiana in the Aso region, Kyushu, Japan, in which relatively large populations still remain, we analyzed the genetics of seven populations of S. kiusiana using five novel microsatellite markers. Each population of S, kiusiana has maintained relatively high genetic diversity (mean H_E = 0.791 and mean N_A =12.0). In addition, the values of pairwise F_<ST> indicating the degree of genetic differentiation among populations were significantly larger than zero between all pairs of populations, although the degrees of difference were small. The semi-natural grasslands in the Aso region have decreased in size over the past several decades, and thus habitat fragmentation may have caused genetic differentiation among populations of S. kiusiana. Although the populations of S. kiusiana have maintained relatively high genetic diversity, the genetic dynamics of S. kiusiana populations should be continuously monitored.

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Viola violacea is a morphologically variable and widely distributed species in Japan. Viola violacea var. violacea, distributed in western Japan, has narrowly ovate to widely lanceolate leaves, while V. violacea var. makinoi has lanceolate to narrowly lanceolate leaves and occurs in eastern Japan, but some populations of V. violacea var. violacea populations have been recorded in eastern Japan. Although the nature of these populations is obscure. We sought to uncover the origin of the disjunct V. violacea var. violacea-like populations in Yamagata Prefecture, Tohoku district by comparing leaf morphology, nuclear ribosomal DNA (nrDNA) ITS, and the trnL-trnF intergenic region of the chloroplast DNA (cpDNA). The leaf morphology of V. violacea var. violacea-like plants in Yamagata was identical to V. violacea var. violacea elsewhere, but the nrDNA ITS sequences of the Yamagata plants were more similar to V. violacea var. makinoi. This clear difference was not found in the cpDNA trnL-trnF region. The incongruity between leaf morphology and molecular traits may be due to V. violacea var. violacea populations that are more closely related to V. violacea var. makinoi or to intraspecific hybridization. To confirm these hypotheses, more extensive study is needed.

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A new species, Persicaria geocarpica, from central Honshu, Japan, is described. The plants are known from only a few sites in northeastern Aichi Prefecture nearby the type locality where they were first discovered. After detailed and intensive field studies, it became clear that the habitat of P. geocarpica is restricted to a particular mountainous area in the Tokai district. Persicaria geocarpica exhibits the unique characteristic that the inflorescences are elongated down to ground level at the end of the long flowering season. There are almost no morphological differences between terrestrial and subterranean flowers, but the latter can self-pollinate in the bud and mature underground without the floral parts expanding.

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The nomenclature of Carex henryi (Cyperaceae) is discussed, with clarification of authorship and designation of a lectotype for the basionym C. longicruris Nees var. henryi C. B. Clarke. Carex henryi was thought to be endemic to China, but here we report its occurrence in the Manaslu Himalaya in central Nepal.

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Gynodioecy and floral dimorphism in Salvia omerocalyx Hayata, an endangered species endemic to central Japan, is here reported for the first time. In three populations of flowering individuals, one population had approximately equal numbers of hermaphrodites (= individuals only with perfect flowers) and male sterile individuals, another population was composed entirely of hermaphrodites, and the third was hermaphroditic except for two individuals with perfect- and male sterile flowers. Examination of herbarium specimens suggested two other localities with male sterile individuals. Male sterile flowers are significantly smaller than hermaphroditic flowers, but there was no difference in seed set between the two floral morphs. Additional field surveys are needed to determine the exact sex expression of the species.

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The family Bonnetiaceae, comprising 35 species in three genera, is one of the nine malpighialean families which are unknown or poorly known with respect to chromosome numbers. Here we report the first exact chromosome count for the family based on Ploiarium alternifolium, using somatic cells from young leaves. The chromosome number of 2n = 22 indicates the base number of the genus to be x = 11. Comparisons with other Malpighiales suggest that x = 11 has occurred as a homoplasy several times within the order.

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