Phylogenetic relationships within Litsea (Lauraceae) and possibly related genera (Actinodaphne, Lindera and Neolitsea) in the tribe Laureae in the Malesian region were investigated at the molecular level. The nucleotide sequences of chloroplast matK and the nuclear ribosomal DNA ITS regions were analyzed. The results were compared with sequence data in a publication based on materials from China. Among the four sections recognized in Litsea, the molecular data confirmed monophyly only of sect. Litsea. Several species of sect. Conodaphne were nested within sect. Cylicodaphne. Sect. Tomingodaphne and sect. Litsea were found to be more closely related to several species of the Lindera than to Litsea sections Conodaphne and Cylicodaphne. Actinodaphne and Neolitsea, were found to be monophyletic. Combined analysis of the matK sequences of the Malesian and Chinese taxa suggested that a careful reexamination of the taxa in China is necessary. Mapping morphological characters on the molecular trees revealed that dimerous flowers were derived from trimerous flowers and two-celled anthers were derived from four-celled anthers.

View full abstract

Arenaria katoana (Caryophyllaceae) is a rare endemic plant that occurs disjunctly on ultramafic rock sites in Japan. This study assessed the degree of genetic distinctness of small, disjunct, isolated populations of A. katoana in Japan. We sequenced several non-coding regions of the chloroplast DNA (trnL intron, trnL-trnF intergenic spacer, psbA-trnH intergenic spacer, and petG-trnP intergenic spacer) and nuclear ribosomal DNA (ITS1, 5.8S nrDNA, and ITS2) to determine the relationships between populations and to evaluate the level of intraspecific genetic variation. Eight different chloroplast DNA haplotypes were detected, and each population exhibited a unique cpDNA haplotype. Four different ITS types, which were shared between populations, were detected. The phylogeny and distribution patterns of the cpDNA haplotypes and the ITS types indicated that A. katoana can be divided into three groups; a central Hokkaido group (Mt. Yubari, Mt. Bozu, and Mt. Furano-nishi-dake), a Mt. Apoi and Mt. Shibutsu group, and a Mt. Hayachine group. The populations of A. katoana have been subjected to the effects of genetic drift and restricted gene flow, both of which promote population differentiation.

View full abstract

The taxonomy of the Vandenboschia radicans complex in the Japanese Archipelago was revised to reflect recent DNA and ploidy analyses. Four diploid species (V. kalamocarpa comb. nov., V. nipponica comb. nov., V. birmanica and V. subclathrata), four tetraploid (amphidiploid) species (V. orientalis, V. hokurikuensis sp. nov., V. miuraensis sp. nov. and V. oshimensis stat. nov.) and four hybrids are recognized. A key to the species excluding the hybrids is given.

View full abstract

A new species, Carex benkei is described on the basis of the specimen from Mt. Tatta-san, Kumamoto Pref., Kyushu, Japan. It is similar to C. brownii, but it differs from C. brownii in having utricles 1.4 times longer, being stipitate at the base, having a beak two times longer, the beak of the achene with or rarely without an annular appendage and the pistillate scales, excluding the awn, two times longer. It is also similar to C. transversa, but it differs in having bidentate, stipitate utricles, the beak of the achene with or rarely without an annular appendage, pistillate scales about two times longer, excluding the awn, and basal sheaths light brown. Carex benkei occurs in Japan (Honshu, Shikoku and Kyushu) and China (An-hui Province). A distribution map of the species is given. A key to the three similar species is presented.

View full abstract

Three new species of the genus Boesenbergia (Zingiberaceae) from Borneo, B. imbakensis, B. laevivaginata and B. subulata are described. A revised key to the Bornean species of Boesenbergia is also provided.

View full abstract

Field observations of Bornean gingers have revealed that Alpinia havilandii and Plagiostachys strobilifera exhibit flexistyly-a novel floral strategy involving extreme stigmatic movement that enhances outcrossing. Alpinia, Amomum, and Etlingera are known to exhibit flexistyly; however, flexistyly in Plagiostachys has remained unconfirmed, although the genus was believed to possess this floral strategy. This report provides concrete evidence of flexistyly in Plagiostachys.

View full abstract