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1.
A distinctive new species of dwarf monocaulous Coffea (Rubiaceae) from Cameroon is described and illustrated. Coffea mapiana is the second dwarf monocaulous known from Cameroon. Its diagnostic characters are elucidated and its taxonomic affinities are discussed; a conservation assessment is provided.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 425–430.  相似文献   

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Phylogeographic analysis of the Coffea subgenus Coffea was performed using data on plastid DNA sequences and interpreted in relation to biogeographic data on African rain forest flora. Parsimony and Bayesian analyses of trnL-F, trnT-L and atpB-rbcL intergenic spacers from 24 African species revealed two main clades in the Coffea subgenus Coffea whose distribution overlaps in west equatorial Africa. Comparison of trnL-F sequences obtained from GenBank for 45 Coffea species from Cameroon, Madagascar, Grande Comore and the Mascarenes revealed low divergence between African and Madagascan species, suggesting a rapid and radial mode of speciation. A chronological history of the dispersal of the Coffea subgenus Coffea from its centre of origin in Lower Guinea is proposed. No relation was found between phylogenetic topology and the age of emergence of the volcanic islands that Coffea species have colonised in the Indian Ocean, suggesting dispersal from mainland Africa after the emergence of the youngest island, Grande Comore, 500,000 years ago. Additional sequences were obtained from GenBank for 24 species of other Rubiaceae genera, including the Rubia genus whose origin has been dated from the Upper Miocene. Estimates of substitution rates suggested that diversification in Coffea subgenus Coffea occurred about 460,000 years ago or as recently as the last 100,000 years, depending on the cpDNA region considered and calibration. The phylogenetic relationships based on plastid sequences confirmed biogeographic differentiation of coffee species, but they were not congruent with morphological and biochemical classifications, or with the capacity to grow in specific environments. Examples of convergent evolution in the main clades are given using characters of leaf size, caffeine content and reproductive mode.  相似文献   

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In this paper our previous chemical study of the anti-dengue active species Faramea bahiensis, Faramea hyacinthina and Faramea truncata (synonym of Faramea caudata) (Rubiaceae) is complemented by isolating from their stems, through a combination of silica gel and Sephadex LH-20 column chromatography and reversed-phase solid-phase extraction, the known iridoid glucosides monotropein (1), monotropein methyl ester (2) and 10-deacetylasperulosidic acid (3). The structures were established by HPLC-DAD-MS/MS analysis, NMR spectroscopy and comparison with literature data. This is the first report on the occurrence of these compounds in the genus Faramea Aubl. This work contributes to expand the knowledge of the chemical diversity of this botanical genus, of which a limited number of identified compounds have been reported.  相似文献   

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Mantalania longipedunculata De Block & A.P. Davis, a new species of Rubiaceae (Gardenieae) from Île Sainte Marie, Madagascar, is described, illustrated, and compared with the three other species in the genus. An extinction risk assessment is given, using the categories and criteria of the World Conservation Union (IUCN).  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 421–424.  相似文献   

7.
The pollen morphology of 38 representative species and varieties within the genus Coffea L. is described. Eight pollen types, placed in two major groups, have been identified on the basis of the number of colpi, colpus characteristics, exine morphology and pollen size. Differences in pollen structures of the species studied do not correspond to present taxonomic groupings, but support a current proposal to place some of the species in the genus Paracoffea Leroy. Among the four sections in the genus, the section Eucoffea contains a high degree of pollen polymorphism.  相似文献   

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团花树中一个新的环烯醚萜苷(英文)   总被引:1,自引:0,他引:1  
从茜草科团花属植物团花树(Neolamarckia cadamba)枝叶的甲醇提取物中分离得到两个环烯醚萜苷,其中一个为新的环烯醚萜苷,利用现代波谱学技术鉴定了其结构为Δ^13,14-plumieride,并命名为plumieride B.  相似文献   

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从黄棉木(Metadina trichotoma(Zoll.et.Mor.)Bakn.)树皮中分离得到2个新的三萜类化合物:3-oxo-29-hydroxy-urs-12-en-27,28-dioicacid(黄棉木素A,1)和3-oxo-21β-hydroxy-urs-12-en-27,28-dioicacid(黄棉木素B,2)。其结构主要通过MS,1D以及2DNMR等波谱方法鉴定。  相似文献   

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根据对中国蛇根草属Ophiorrhiza植物标本的研究和野外调查,将琼崖蛇根草O.aureolina f.qiongyaensis Lo和溪畔蛇根草O.humilis Tseng归并入短小蛇根草O.pumila Champ.ex Benth.,将海南蛇根草O.hainanensis Tseng归并入垂花蛇根草O.nutans C.B.Clarke,将广西蛇根草O.kwangsiensis Merr.exLi和变黑蛇根草O.nigricans Lo归并入日本蛇根草O.japonica Bl.,将龙州蛇根草O.longzhouensis Lo和圆锥蛇根草O.paniculiformis Lo归并入广州蛇根草O.cantoniensis Hance。  相似文献   

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Brian M. Boom 《Brittonia》2005,57(2):105-107
Remijia hubbardiorum B. M. Boom, endemic to white sandcampinas orerra firme forest in the Rio Uatumã region in the State of Amazonas of north central Brazil, is described and illustrated, and its morphological differentiation with respect toR. asperula Standley is discussed.  相似文献   

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The Malagasy representatives of the large African genus Tricalysia (tribe Coffeeae s.l.) are revised. Three Malagasy species were hitherto recognized in the genus, namely T. cryptocalyx , T. madagascariensis , and T. ovalifolia . In this study, two species, T. boiviniana and T. leucocarpa , are transferred from the genus Hypobathrum and seven new species and two new subspecies are described, raising the species number for Tricalysia to a total of 12. This marked increase in species number is a recurring pattern for many Malagasy genera in systematically poorly known families such as Rubiaceae. All the species are described in detail and illustrated, and a list of exsiccatae and a distribution map are provided. Furthermore, the characters of the Malagasy taxa are compared with those of the continental African species, and their infrageneric status is discussed. With the exception of T. ovalifolia , a member of subgenus Empogona , all Malagasy species belong to subgenus Tricalysia . Because of their unisexual flowers, these species cannot be accommodated within one of the four existing sections in subgenus Tricalysia . A new section, Androgyne , is therefore recognized.  © 2007 National Botanic Garden of Belgium. Journal compilation © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 83–126.  相似文献   

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根据对保存于湖南师范大学生命科学学院植物标本馆(HNNU)、中国科学院华南植物园植物标本馆(IBSC)、中国科学院昆明植物研究所植物标本馆(KUN)和中国科学院植物研究所植物标本馆(PE)的茜草科(Rubiaceae)蛇根草属(Ophiorrhiza Linn.)标本的研究,将金黄蛇根草(Ophiorrhiza aureolina Lo f. aureolina)和绿春蛇根草(O. luchunensis Lo)处理为变红蛇根草(O. subrubescens Drake)的新异名。  相似文献   

14.
耳草属(茜草科)植物的两个新种=Two new species of the genus Hedyotis (Rubiaceae) from China[刊,中]/ 王 瑞 江(中国科学院华南植物研究所 广州 510650),邢 福 武//植物分类学报.—2002,41(1).—85~88 摘要:描述了国产耳草属(茜草科)植物的两个新种,启无耳草Hedyotis wangii R. J. Wang和崖州耳草H. yazhouensis F. W. Xing et R. J. Wang。  相似文献   

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A new species of Coffea from southern central Madagascar, C. toshii, is described and illustrated. The new species is similar to C. buxifolia but differs due to its short, broad spreading habit (vs narrow habit), conspicuous domatia (vs inconspicuous), consistently red fruit (vs reddish purple to dull purple or red), longer fruiting pedicel (vs shorter), presence of bracts (vs absence) and occurrence at lower elevations (vs high elevation).  相似文献   

16.
对螺序草属(Spiradiclis B1、)16种2变型共18个样品的种子形态特征的初步研究表明,本属植物种子为小型(0.2—0、3mm)或中型(0.3—2mm),整体形状不太规则,表面纹饰为蜂窝状,种脐稍突出。种子的外壁由内外2层种皮组成。依据表面突起分布方式,螺序草属的种子大致分为2种类型:(1)平周壁微下陷,疣突均匀分布于其上,如大叶螺序草、螺序草、尖叶螺序草、柳叶螺序草、峨嵋螺序草和龙州螺序草;(2)平周壁下陷成穴状,突起分布在穴边缘,如红花螺序草、心叶螺序草、两广螺序草、广东螺序草、海南螺序草、宽昭螺序草、疏花螺序草、多枝螺序草、罗氏螺序草、小叶螺序草、石生螺序草和紫花螺序草。螺序草属的种子形态特征对属下类群的划分具有重要的参考价值。  相似文献   

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The potential application of DNA barcodes of plastid (matK, trnH–psbA, petD, and rbcL) and nuclear (internal transcribed spacer (ITS) of rDNA) DNA regions was investigated for 25 Hedyotis taxa. The ITS showed the best species discrimination by resolving 23 of the species as exclusive lineages with no shared alleles between any of the 24 distinct species (H. assimilis and H. mellii are not supported as distinct species based on our molecular and morphological data). Conversely, rbcL performed the worst and only resolved 10 of the species as exclusive lineages, and 10 species with shared alleles. Using ITS has the advantage of high PCR amplification success and it provides good intra- and interspecific variation distribution patterns. The most powerful plastid markers were petD and trnH–psbA, but we could amplify and sequence trnH–psbA for only 83% of the accessions sampled. Combination of ITS and petD performed extremely well, with all 24 of the distinct species resolved as exclusive lineages and no shared alleles between any of the distinct species. We therefore recommend ITS, or a combination of ITS and petD, as the standard DNA barcode in Hedyotis, but acknowledge that there are no shared alleles between distinct species for matK and rbcL combined.  相似文献   

18.
螺序草属(茜草科)的花粉形态   总被引:3,自引:0,他引:3  
首次对螺序草属(Spiradiclis B1.)的11种和1变型共16份植物的花粉样品在光镜和电镜下进行了观察。结果表明,本属植物花粉为单粒,小型和中型花粉,近球形至椭球形,辐射对称,常具3孔沟,偶为4孔沟,外壁表面纹饰为孔状。花粉外壁由不连续的具穿孔的覆盖层、柱状结构和基层组成,内外壁明显。此外,本属植物的花粉具有花粉2型和“芽状”结构的现象。螺序草属植物的花粉形态在属下分类上有一定的局限性,但是在个体的系统发育上却可以提供极有价值的信息,如具有花粉单型的种类比花粉二型的种类进化。  相似文献   

19.
Mussaenda yunnanensis, a new dioecious species of Rubiaceae from Yunnan Province, China, is described and illustrated. The new species can be recognized by its slender stem, congested‐cymose inflorescences and long corolla tubes. Differences between M. yunnanensis and two morphologically similar species (M. pubescens and M. antiloga) are presented. We also provide a key to all dioecious species of Mussaenda in China. The delimitation of the new species is further supported by molecular phylogenetic analyses based on eight plastid loci.  相似文献   

20.
A new species, Pavetta puffii, is described and illustrated from Assam, northeast India. The taxonomic relationships of the new species with the hitherto known species of genus Pavetta are examined and discussed.  相似文献   

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