Biosystematics of Indo-Chinese Flora

1994年6月，岩城K.K.Iwatsuki参观了巴黎自然历史博物馆，并根据标本馆保存的标本对《印度-中国的植物群》进行了调查。在1994年12月至1995年1月期间，K.Iwatsuki、N.Murakami和J.Yokyama(该项目的助理成员)访问了越南、老挝和泰国。我们与泰国的C.Phengklai、老挝的B.Svengsukusa和越南的N.N.Thin合作，收集了2000多份标本和许多DNA样本。今年，我们在越南北部的考察中取得了重要成果。这一地区是植物地理上重要的地方，特别是当我们考虑到日本和中国植物的物种形成时。在种子植物方面，我们采集了许多桑科、天南星科、茜草科、山茶科和菊科在那个季节开花结实的标本。我们在天南星科天南星属Sapa山林中采集到一新种。新种的近缘种尚未在中国采集到，因此在天南星的物种形成研究中具有一定的参考价值。我们对这些标本的研究正在进行中。对于蕨类植物，我们收集了许多膜翅属和新蕨属(侧柏科)的标本。这两个类群的形态都很简单，很难识别该物种。因此，我们从发现这些植物的每个地方收集了DNA样本和标本，并在回到日本后对它们进行了详细的比较。我们已经从其中一些样本中测定了rbcL基因的核苷酸序列，并发现了几个分子上可区分的分类单位。对我们的标本和印支中国标本的进一步分析将使我们对该群体有更深入的了解。

In June, 1994, K.Iwatsuki visited Paris Natural History Museum and investigated "Flora of Indo-China" based on the specimen deposited in their herbarium. During December, 1994 - January, 1995, K.Iwatsuki, N.Murakami and J.Yokoyama (assistant member of this project) visited Vietnam, Laos, and Thailand. Collaborating with C.Phengklai (Thailand), B.Svengsukusa (Laos) and N.N.Thin (Vietnam), we collected more than 2000 numbers of herbarium specimens and many DNA samples.This year, we got important results from our expedition to Northern Vietnam. This area is plant geographically important place, especially when we consider speciation of Japanese and Chinese plants. However, this area has not been well botanized and thus our expedition can contribute to great advances in understanding of the Flora and its evolutionary origin.For seed plants, we collected many specimen of Moraceae, Araceae, Rubiaceae, Cameliaceae and Compositae which had flowers and fruits in that season. We collected a new species of Arisaema (Araceae) from the mountain forest of Sapa. No related species to the new species have ever been collected in China, and thus is valuable when we consider speciation of Arisaema. Our study on these herbarium specimens are in progress.For ferns, we collected many specimens of Hymenasplenium and Neottopteris (Aspleniaceae). Both of the groups are very simple in morphology and hard to recognize the species. Therefore, we collected DNA samples as well as herbarium specimens from every localities where we found these plants, and made detailed comparison between them after we came back to Japan. We already determined nucleotide sequences of rbcL gene from some of these samples, and found several molecularly distinguishable taxonomic units. Further analyzes on our samples and specimen from Indo-China will lead us to deep understanding of the group.