Veronicastrum sibiricum var. zuccarinii (Plantaginaceae) is an endangered perennial herb native to semi-natural grasslands in southern Korea and Kyushu, Japan. To elucidate the genetic status of V. sibiricum var. zuccarinii in the Aso region of Kyushu, in which relatively large populations still remain, we analyzed seven populations using five novel microsatellite markers. Each population of V. sibiricum var. zuccarinii has a maintained moderate level of genetic diversity (mean H E = 0.596, mean N A = 5.6, and mean AR = 4.7). Pairwise F ST indicated significant genetic differentiation between all population pairs (0.065−0.309). The semi-natural grasslands in the Aso region have decreased in area over the past decades. Thus, habitat fragmentation may be causing genetic differentiation among populations of V. sibiricum var. zuccarinii. Although the populations of this variety have maintained a moderate degree of genetic diversity, the dynamics of gene flow among them should be continuously monitored.
A new section, Euphorbia sect. Bokorenses under subgenus Euphorbia is established for Euphorbia bokorensisH. Toyama & Tagane, sp. nov., endemic to Bokor National Park, Cambodia. Euphorbia sect. Bokorenses is distinguished from related sections Denisophorbia and Goniostema by unbranched stems and smooth seeds, respectively. Bayesian phylogeny using matK, ndhF, and ITS regions supports its monophyly from the currently recognized 21 sections. It has a sister relationship with the Malagasy clade, including sections Denisophorbia, Deuterocalli and Goniostema, and to the northeastern African clade, including sect. Rubellae. A description, illustration, photographs and preliminary conservation status of the new species, and an updated identification key to the sections of Euphoria subg. Euphorbia is provided.
Previous studies recorded two genera and three species of Podostemaceae from a single river in Phitsanulok Province, northern Thailand. Recent extensive field research resulted in finding six additional species, i.e., two new species (Dalzellia sparsa and Hydrobryum mandaengense ) and four new records for the province (Terniopsis minor, Thawatchaia trilobata, Hy. phetchabunense , and Hy. tardhuangense ). Dalzellia sparsa is characterized by the various leaves on the cupule, and Hy. mandaengense has disporangiate anthers with tortuous dehiscence. In total, five genera and nine species (five of which belong to Hydrobryum ) occur in the province, with the result that Phitsanulok is the second most species-rich province, next to the adjacent Loei, for Thai Podostemaceae. Eight of the nine species known from the province are endemic to Thailand; Hy. tardhuangense occurs also in Laos. Among the endemics, D. sparsa, Hy. bifoliatum, Hy. kaengsophense and Hy. mandaengense are restricted to one or two river systems in Phitsanulok; the remaining four species occur widely. The descriptions of Hanseniella heterophylla, Hy. phetchabunense , and Hy. tardhuangense is emended using new collections. A key to all 49 species of Thailand has been updated.
A plant morphologically intermediate between Viola rostrata Pursh var. japonica (W. Becker et H. Boissieu) Ohwi and V. violacea Makino var. makinoi (H. Boissieu) Hiyama ex F. Maek. was found in Iwate Prefecture, Tohoku District, northern Japan. Molecular analysis based on sequences of internal transcribed spacer regions of nuclear ribosomal DNA and trnL-trnF intergenic region of chloroplast DNA indicated that the intermediate plant was a hybrid between those two species and that the maternal parent was V. rostrata var. japonica . This is the first report of a naturally occurring intersubsectional hybrid of subsect. Rostratae Kupffer and subsect. Adnatae W. Becker.
Cyperus pacificus (Ohwi) Ohwi var. margoinflatus S. Fujii, a new variety of C. pacificus (Cyperaceae) is described. It closely resembles C. pacificus var. pacificus in the oblong-ellipsoid achenes with winged margins, but the margins are well inflated with spongy parenchyma. It usually occurs in the dried bottoms of irrigation ponds, and often intermixed with other species of Cyperaceae such as C. extremiorientalis Ohwi, C. nipponicus Franch. et Sav. var. nipponicus and var. spiralis Ohwi, Fimbristylis dipsacea (Rottb.) C.B. Clarke, and F. squarrosa Vahl var. esquarrosa Makino. A key to the new variety and closely related taxa is also provided.