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1.
Piper viridescens sp. nov. is proposed based on material from northern Thailand. The new species is described and illustrated, resulting from a revision of the genus in Thailand. The new species is most closely related to P. boehmeriifolium (Miq.) C. DC. A table comparing diagnostic features of P. viridescens, P. boehmeriifolium and P. retrofractum is provided.  相似文献   

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中国鳞毛蕨属泡鳞亚属的分类研究   总被引:2,自引:0,他引:2  
陆树刚   《广西植物》1999,19(2):105-118
鳞毛蕨属DryopterisAdans.泡鳞亚属SubgenusErythrovariae(H.Ito)Fraser-JenkinsinBul.Br.Mus.Nat.Hist.Bot.14(3):195.1986.Type:Dryopterisery...  相似文献   

3.
兰科盆距兰属(Gastrochilus)植物的修订   总被引:1,自引:0,他引:1  
吉占和   《广西植物》1996,16(2):123-154
本文对盆距兰属(Gastrochilus)植物作了修订,共分3个组,含46种和1变种,其中1个组(Sect.Caespitosi)和8个种(G.carnsus,G.garhwalensis,G.linearifolius,G.guangtungensis,G.subpapillosus,G.nanchuanensis,G.saccatusandG.gongshanensis)为新的,首次在本文作了描述报导。本属属的形态特征,研究历史和订正后属下的分类群检索表,种的文献引证、简短的特征记要和地理分布以及在属中被排除的分类单位索引均提供在本文。  相似文献   

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Two new species of Polystachya Hook. are described and illustrated: Polystachya rydingii Baranow & Mytnik occurring from the Democratic Republic of Congo and P. sosefii Baranow & Mytnik from Cameroon. The species belong to the section Polystachya Kraenzl., which is the only pantropical section in the genus. Maps of the distribution for the new species and their closest relatives and a brief discussion with notes on their habitat, ecology, and altitude are provided.  相似文献   

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Didymodon kunlunensis D.P.Zhao, S.Mamtimin & S.He is described as a new species found in Xinjiang, China. The new species is characterised by a combination of the following characters: ovate leaves with laminal cells always smooth, red colour in KOH, recurved leaf margins from base to apex, a percurrent costa without dorsal and ventral stereid bands in cross section, a distinct stem central strand and the presence of gemmae in the leaf axils. Light microscope photographs of the significant characters are provided and its distinctions from closely related taxa are discussed. A key to Chinese Didymodon species with smooth laminal cell is provided.  相似文献   

11.
Pseudoplatystoma is a commercially important genus of Neotropical migratory catfishes widely distributed in all major river basins of South America. Historically, only three species were recognized, but a recent revision proposed eight putative morphospecies for the genus. A molecular study based on mitochondria DNA (mtDNA) provided support for recognition of only some of the species and raised questions about species boundaries in this group. We present a more encompassing analysis based on mtDNA (cytochrome b, 818bp) and nuclear DNA-based phylogenies (Rag1 intron 1, 664bp and S7 intron 1, 635bp) for a more extensive sampling (279 individuals from 42 localities) of all putative species in all major river basins. Patterns generated by individual gene genealogies and a multispecies coalescent analysis provided evidence to suggest recognition of only four distinct species in this genus: Pseudoplatystoma magdaleniatum, Pseudoplatystoma corruscans, Pseudoplatystoma tigrimun (sensu lato) and Pseudoplatystoma fasciatum (sensu lato). The species phylogeny places P. magdaleniatum as the sister group to all the other species in the genus, but the relationships among P. fasciatum s.l, P. tigrimum s.l., and P. corruscans could not be resolved with confidence.  相似文献   

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The present paper deals with the genus Paeonia in Xinjiang, whose taxonomy has been confused. Based on the field observation, population sampling and the examination of herbarium specimens, a taxonomical revision is made in this paper. Two species are recognized, i. e. Paeonia anomala L. and P. sinjiangensis K. Y. Pan. P. altaica K. M. Dai et T. H. Ying is reduced to P. sinjiangensis and P. hybrida (= P. anomala var. intermedia) is reduced to P. anomala. The diagnostic characters of the two species are described and illustrated, and a map of their distribution in Xinjiang is presented. A key to these two species is provided here. 1. Roots straight, not thickened; sepals all caudate, less frequently one or very rarely two non-caudate ................................................ 1. P. sinjiangensis K. Y. Pan. 2. Roots fusiform or tuberous; inner three sepals non-caudate, less frequently one of them caudate .............................................................. 2. P. anomala L. key words Xinjiang; Paeonia; P. anomala; P. sinjiangensis; revision  相似文献   

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铁线莲属绣球藤组修订   总被引:14,自引:8,他引:6  
笔者在中国科学院植物研究所标本馆和欧、美一些著名植物标本馆研究了铁线莲属植物标本之后,完成了此属绣球藤组的修订,确定此组含有22种和23变种。本文还提供了组下分类群的检索表、各种植物的形态描述、地理分布、生长环境等,并附有多幅插图。笔者曾在2000年根据此组的重要形态特征的演化趋势制定出一个新分类系统,此系统在本修订中继续得到应用。此组重要形态特征的演化趋势的原始状态是:萼片平展,呈倒卵形,顶端圆形或钝,外面边缘无狭短绒毛带;雄蕊花药呈长圆形或狭长圆形,药隔顶端不突出;花组成具花序梗和2枚分生苞片的聚伞花序,生于当年生枝叶腋。衍生状态是:萼片斜上展或近直立,变狭呈长圆形、长椭圆形、披针形或倒披针形,顶端急尖、渐尖或渐狭,外面边缘出现狭短绒毛带(仅文山铁线莲一种);雄蕊花药呈条形,药隔顶端有小突起;花组成具花序梗和2苞片合生形成总苞的聚伞花序,或花单生,只具花梗,而无花序梗和苞片,自老枝的腋芽中生出。在铁线莲属近300种植物中,具有上述原始特征的只有6种:短梗铁线莲C.brevipes、美花铁线莲C.potaninii、绣球藤C.montana、薄叶铁线莲C.gracilifolia、丽叶铁线莲C.venusta和金毛钱线莲C.chrysocoma。这6种中有5种特产我国西南部横断山区一带,只1种(绣球藤)分布较广,东自我国台湾省向西经过我国亚热带山区分布到喜马拉雅西部。此外,简要回顾了本组的分类历史,绘出本组分布区图,以及讨论了铁线莲属中具花序梗和二苞片的聚伞花序在此属各演化路线中出现的简化成仅具花梗单花的现象。  相似文献   

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Astragalus rahiminejadii , a new species endemic to Iran, is described and illustrated. This species, which belongs to section Astragalus , is confined to the western part of Iran (Prov. Kermanshah) and is known only from a single population. Seed testa morphology as viewed under the scanning electron microscope is discussed and photomicrographs are provided. In addition, the geographical distribution and ecology of the species belonging to this section are discussed.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 363–368.  相似文献   

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Protium sectionPepeanthos, a neotropical group of nine species ranging from Costa Rica to the southern perimeter of Amazonia, is described, as are the group's five new species:P. calendulinum, P. gallosum, P. pecuniosum, P. retusum, andP. urophyllidium. Keys are provided to flowering and to fruiting material. The new section is characterized by a milky resin; lateral leaflet pulvinuli inconspicuous or absent; style short-branched and the stigmas caudiculate and spiculate; and the cotyledons plano-convex.  相似文献   

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A taxonomic revision of the genus Phryganogryllacris Karny, 1937 is provided. Twelve species of the genus from China are recorded, including 5 species described as new to science, namely P. sichuanensis Li, Liu Li, sp. nov., P. parva Li, Liu Li, sp. nov., P. truncata Li, Liu Li, sp. nov., P. interrupta Li, Liu Li, sp. nov. and P. longicerca Li, Liu Li, sp. nov. Two new combinations are also reported here, P. gialai(Gorochov, 2004)(Vietnam) comb. nov. and P. alia(Gorochov, 2004)(Vietnam) comb. nov. A key to Chinese species of the genus was provided.  相似文献   

19.
Plants in Paeonia sect. Moutan DC., whose wild types are endemic to China, are deciduous subshrubs. Taxonomic treatments of most species in this section have long been in dispute. To address this question, both intraspecific and interspecific relationships of the species in this section were analyzed using RAPD markers. The dendrogram constructed by UPGMA showed that the accessions of the same species were always grouped together earlier than those of different species. The intraspecific similarity coefficients ranged from 0.60 to 0.90, grouping precisely those species of the same subsection together. Hence, the seven species under question can be well distinguished from each other. The similarity coefficient between P. delavayi and P. ludlowii was 0.60, and they were clustered in a clade. The similarity coefficients between P. jishanensis and the three species P. rockii, P. ostii, P. qiui, and between P. jishanensis and P. decomposita were both 0.48. These five species were clustered in another clade. These two clades corresponded well to Subsect. Delavayanae and Subsect. Vaginatae. Our results support the taxonomic treatment of Sect. Moutan re- cently proposed by Hong (1998,1997).  相似文献   

20.
芍药属牡丹组的系统学研究——基于RAPD分析   总被引:41,自引:5,他引:36  
芍药属牡丹组(Paeonia sect.Moutan DC)是落叶亚灌木,其野生类群为我国特有。长期以来不同 学者根据形态性状对这个组中种的分类处理不断修正,不断有新种描述。我们采用RAPD标记分析了 牡丹组种内与种间遗传关系。从10个RAPD引物获得121个多态位点。用UPGMA方法构建的树系 图表明每个种的所有个体都各自聚为一支,种内的相似性系数为0.60~0.90,因此现有的7个种能很好 地区分开来。P.delavayi与P.ludlowii相似性系数为0.60,聚为一支;P.jishanensis与P.rockii、P. ostii、P.qiui以及P.decomposita之间的相似性系数为0.48,聚为一大支。这两支与肉质花盘亚组和革 质花盘亚组相对应。这些结果与洪德元根据形态性状对该组所做的分类处理基本相符。我们认为RAPD技术用于牡丹基因组分析是灵敏而行之有效的工具。  相似文献   

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