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1.
Ranunculus is distributed in all continents and especially species-rich in the meridional and temperate zones. To reconstruct the biogeographical history of the genus, a molecular phylogenetic analysis of the genus based on nuclear and chloroplast DNA sequences has been carried out. Results of biogeographical analyses (DIVA, Lagrange, Mesquite) combined with molecular dating suggest multiple colonizations of all continents and disjunctions between the northern and the southern hemisphere. Dispersals between continents must have occurred via migration over land bridges, or via transoceanic long-distance dispersal, which is also inferred from island endemism. In southern Eurasia, isolation of the western Mediterranean and the Caucasus region during the Messinian was followed by range expansions and speciation in both areas. In the Pliocene and Pleistocene, radiations happened independently in the summer-dry western Mediterranean-Macaronesian and in the eastern Mediterranean-Irano-Turanian regions, with three independent shifts to alpine humid climates in the Alps and in the Himalayas. The cosmopolitan distribution of Ranunculus is caused by transoceanic and intracontinental dispersal, followed by regional adaptive radiations.  相似文献   

2.
A new system of classification of the genus Clematis is proposed. The taxonomic history of the genus is briefly reviewed. On the basis of the analyses of various morphological and palynological characters, evolutionary trends of some characters are revealed as follows: 2. Seed germination: epigeal→hypogeal. 3. Leaf: (a) phyllotaxy: alternate→opposite→verticillate. (c) texture: herbaceous→papery→subcoriaceous or coriaceous. 4. Inflorescence: (a) position: terminal→terminal and axillary→axillary. (b) type: pedunculate, bibracteate, several-flowered cyme. (i) 3–4 times branched, 20–35-flowered cyme→many-branched ca. 100-flowered panicle. (ii) 1-flowered cyme→a single flower, pedicellate, but with peduncle and bracts wanting. 5. Flower: (a) Sexuality: bisexual→unisexual. (b) Posture: erect, with straight pedicel→pendulous, with recurved pedicel. 6. Sepal: (a) number per flower: 4 or 5→6–8. (b) aestivation: valvate→imbricate. (c) colour: white or yellow→blue, purple or red. (d) spreading direction: spreading→ascending→erect. (e) texture: herbaceous or papery→subcoriaceous or coriaceous. (f) shape: obovate→obovate-oblong, oblanceolate, lanceolate or oblong→narrowly oblong→linear. (g) apex: rounded or obtuse→acute→acuminate→attenuate (h) margin indumentum: glabrous or puberulous→with a narrow velutinous strip. (i) margin dilation: not dilated→dilated. (j) indumentum of adaxial surface: glabrous→puberulous→velutinous. 7. Stamen: (a) indumentum: glabrous→filament hairy yet anther glabrous→both filament and anther hairy. (b) filament: (i) linear→proximally or distally widened, or entirely so. (ii) flat→rugose. (c) anther: oblong, 0.8–3.5 mm long→narrowly oblong, 2–6 mm long→linear, up to 7–10 mm long. (d) connective: not projected→apex minutely apiculate, with an apiculum ca. 0.1 mm long→apex with a conic or subglobose projection 0.1–0.2 mm long→apex with a subulate projection up to 4 mm long or with a narrowly lamellate projection 1–10 mm long. 9. Staminode: (a) absent in bisexual flower→present in bisexual flower. (b) number per pistillate flower: numerous→few→zero. 10. Style: not elongate→elongate and plumose→slightly elongate and appressed-puberulous, then tail-like or subulate in shape→very short, slightly or not elongate, appressed- puberulous or glabrous. 11. Fruit: not complanate, nor rimmed, nor marginate→complanate, narrowly to tumidly rimmed→complanate, broadly marginate or winged. According to the evolutionary trends mentioned above and mainly according to the floral structure, the relationships among the 15 sections of Clematis are discussed, and four evolutionary stocks are recognized. Of them, the C. montana stock, in which C. brevipes, C. potaninii, C. montana etc., all with spreading, white, obovate sepals and glabrous stamens, are included, is regarded as the primitive group of the genus, whereas the other three, C. vitalba stock, C. connata stock, and C. alpina stock, are regarded as more advanced. All these four stocks might be derived from a putative extinct primitive group of the genus, which might possess the most primitive vegetative and reproductive characters. The four stocks are all treated as subgenera in the present system. Finally, a systematic enumeration of all the infrageneric taxa is presented and their brief diagnoses are given.  相似文献   

3.
铁线莲属一新分类系统   总被引:36,自引:0,他引:36  
提出毛茛科Ranunculaceae铁线莲属Clematis一新分类系统。首先,简要回顾了此属的分类学研究历史,继对此属的营养器官和生殖器官的重要形态特征和花粉特征进行了分析,揭示出一系列演化趋势。这些趋势,尤其是萼片和雄蕊的演化趋势说明在现存的铁线莲属植物中,绣球藤Clematis montana与其少数近缘种的花构造最接近比铁线莲属原始的银莲花属Anemone,因此,包括绣球藤等植物的绣球藤组sect. Cheirpsis被认为是铁线莲属的原始群。主要根据花构造对铁线莲属现存的15组的亲缘关系进行了分析,发现它们是在4条演化干(绣球藤干、欧洲铁线莲干、尾叶铁线莲干、长瓣铁线莲干)的演化过程中先后形成的。本文将此4条演化干处理为亚属。最后做出属下各级分类群的系统排列,并给出简要的形态特征。  相似文献   

4.
5.
The origin and status of the name Ranunculus ficaria L. var. or ssp. fertilis is discussed and the infraspecific name is validated. — Flora Nordica Notes No. 27.  相似文献   

6.
Leaf polymorphism in Ranunculus nanus Hook. (Ranunculaceae)   总被引:1,自引:1,他引:0  
  相似文献   

7.
A new species,Ranunculus lambayequensis, from the department of Lambayeque in Peru with pocket-like nectary scales and smooth and turgid achenes appears to be related toR. donianus andR. bangii of sectionEpirotes.  相似文献   

8.
9.
The alpine white-flowered buttercup, Ranunculus kuepferi Greuter & Burdet, is a polyploid complex with diploids endemic to the southwestern Alps and polyploids – which have been previously described as apomictic – widespread throughout European mountains. Due to the polymorphic status of both its ploidy level and its reproductive mode, R. kuepferi represents a key species for understanding the evolution of polyploid lineages in alpine habitats. To disentangle the phylogeography of this polyploid taxon, we used cpDNA sequences and AFLP (amplified fragment length polymorphism) markers in 33 populations of R. kuepferi representative of its ploidy level and distribution area. Polyploid individuals were shown to be the result of at least two polyploidization events that may have taken place in the southwestern Alps. From this region, one single main migration of tetraploids colonized the entire Alpine range, the Apennines and Corsica. Genetic recombination among tetraploids was also observed, revealing the facultative nature of the apomictic reproductive mode in R. kuepferi polyploids. Our study shows the contrasting role played by diploid lineages mostly restricted to persistent refugia and by tetraploids, whose dispersal abilities have permitted their range extension all over the previously glaciated Alpine area and throughout neighbouring mountain massifs.  相似文献   

10.
( 1 ) Nine species and 4 varieties are described as new, and 2 new ranks, 1 new combination, and 1 new name are proposed. (2) Clematis dioica L. ssp. virginiana (L.) Kuntze var. bahamica Kuntze, C. bahamica (Kuntze) Britton, C. orbiculata Correll, C. brasiliana DC. var. laxa St. Hilaire, C. perulata Kuntze, C. barrancae Jones, C. discolor Gardn., C. laxiflora Baker, C. bathiei Lévl., and C. mauritiana Lam. var. sulfurea Viguier & Perrier are reduced into synonymy. (3) A new classification for the varieties of C. chinensis Osbeck is proposed. (4) The specific status of C. flukenetii DC. is discussed and confirmed. (5) The differences between C. acapulcensis Hook. & Arn., the South American population of which has been misidentified as C. affinis St. Hilaire, and its close ally, C. affinis St. Hilaire, are given. (6) The taxonomical confusion made by Viguier and Perrier about the species belonging to sect. Meclatis subsect. Wightianae distributed in Madagascar and adjoining islands is clarified, and an enumera-tion of them with a key is given.  相似文献   

11.
铁线莲属研究随记(Ⅴ)   总被引:3,自引:0,他引:3  
(1)描述了9新种,4新变种;做出了2新等级,1新组合和1新名称。(2)归并了以下拉丁学名: Clematis dioica L.ssp.virginiana(L.)Kuntze var.bahamica Kuntze,C.bahamica (Kuntze) Britton,C.orbic- ulata Correll,C.brasiliana DC.var.laxa St.Hilaire,C.perulata Kuntze,C.barranacae Jones,C.discolor Gardn., C.laxiflora Baker,C.bathiei Lévl.和C.mauritiana Lam.var.sulfurea Viguier &; Perrier。(3)对威灵仙C.chinensis Osbeck的5个变种进行了分类;特产日本的C.fujisanensis Hisauti &; Hara与C.chinensis 极为相近,主要区别在于具较大的花,但有时花与C.chinensis的花同样大,由于区别不大,在本文中被 降级作变种处理;与其近缘、具强烈退化花序、特产华东的C.anhweiensis M.C.Chang也随之被处理为 变种。(4)瑞典学者Johnson在最近出版的铁线莲属专著中将特产西印度群岛东部的C.Flukenetii DC. 归并于特产美国东南部的C.catesbyana Pursh;本文不同意他做出的归并,并列出了这两个种的明显区 别特征,确认后者是一个应该得到承认的独立的种。(5)根据墨西哥标本描述的C.acapulcensis Hook. &; Arn.原知分布于中美一带,而其在南美的居群和一小叶多毛的新变种(var.puberula)过去长期间被误 定为其近缘种C.affinis St.Hilaire;这个混乱在本文中得到澄清,同时,本文给出了这二近缘种的区别 特征。(6)Viguier和Perrier两位学者在上世纪四十年代末研究马达加斯加一带的黄花铁线莲组-怀特铁 线莲亚组(sect.Meclatis subsect.Wightianae)植物时做出了不少错误鉴定:(a)将特产马达加斯加的具三 出复叶的C.mauritiana Lam. var.mauritiana,var.coriacea和C.microcuspis Baker,以及具单叶的C.ac- tinostemmatifolia W.T.Wang均鉴定为分布于非洲大陆的C.simensis Fresen., 并将后者作为分布于亚洲和欧洲的C.orientalis L.的亚种处理;(b)将特产马达加斯加具三出复叶的C.laxiflora Baker和具一回羽状复叶的C.ibarensis Baker鉴定为特产印度南部的C.wightiana Wall.,也将后者作为C.orientalis的亚种处理;(c)将特产科摩罗(Comoros)具二回羽状复叶的C.comoresensis W.T. Wang鉴定为C.brachiata Thunb.,也将后者作为C.orientalis L.的亚种处理;(d)将C.ibarensis Baker(具一回羽状复叶和两性花)这一拉丁学名用在了另一特产马达加斯加具2~3回羽状复叶和单性花、应属于单性铁线莲组sect. Aspidanthera的种(C.rutoides W.T.Wang)之上;(e)将另一特产马达加斯加具一回羽状复叶和单性花、 也属于单性铁线莲组的C.edentata Baker(=C.insidiosa Baill.)降级作为这两位学者曲解的C.ibarensis Baker的亚种处理;(f)将特产马达加斯加的C.dissecta Baker归并到属于茴芹叶铁线莲组(sect. Pseudanemone)的C.pimpindllifolia Hook.中。此次本文第五部分继去年第一、二部分之后对上述混乱情况做出了完全澄清,并给出了分布于马达加斯加及其邻近岛屿的怀特铁线莲亚组8种植物的检索表;由于C.ibarensis Baker的定义被上述两位学者严重误解,本文根据较多具花、果的标本写出了此种完整、正确的形态描述。  相似文献   

12.
中国乌头属植物药用亲缘学研究   总被引:17,自引:0,他引:17  
毛莨科Ranunculaceae乌头属Aconitum L.植物作为有毒植物及药用植物一直受到广泛的关注。本属全世界约有300余种,其中超过半数分布在中国。本文在总结乌头属二萜生物碱的化学分类及其分布、特征性二萜生物碱及其分类价值以及二萜生物碱的生源关系及其分类学意义的基础上,结合其毒性和疗效讨论了国产乌头属植物亲缘关系、化学成分和疗效及毒性之间的相关性,亦即药用亲缘学的初步研究。发现牛扁亚属subgen.Lycoctonum是以牛扁碱和C18-二萜生物碱为主的类群,由于其毒性中等,因而是寻找镇痛、抗炎等新药的一个对象。从二萜生物碱化学成分来看,露蕊乌头亚属subgen.Gymnaconitum并不显得最为进化,对其分类位置尚难作出最后的结论。乌头亚属subgen.Aconitum亚属下系之间的化学分类表现出如下特征:(1)唐古特乌头系ser.Tangutica和圆叶乌头系set.Rotundifolia是以内酯型二萜生物碱为主的类群,毒性较小,是新药寻找的重点研究类群。保山乌头系ser.Bullatifolia以C20-二萜生物碱如光翠雀碱和宋果灵以及C19-二萜生物碱如乌头碱、滇乌碱和尼奥灵等为主。短柄乌头系see Brachypoda显示以3-乙酰乌头碱、乌头碱、伏乌碱等高度进化的乌头碱型二萜生物碱为主,胺醇类如尼奥灵次之,有时共存其他纳哌啉型C20-二萜生物碱的特征。准噶尔乌头系ser.Grandituberosa的化学特征是以高度进化的乌头碱型如乌头碱等和比较原始的胺醇如塔拉萨敏、尼奥灵等以及C20-二萜生物碱为主,均有较大毒性。褐紫乌头系ser.Brunnea则以C20-二萜生物碱如光翠雀碱和宋果灵为主,杂有高度进化的乌头碱型二萜生物碱如乌头碱等成分。化学分类上不支持其独立成为一个分支。以上各系组成乌头亚属的原始和中间过渡类群。其中唐古特乌头系和圆叶乌头系最为相近,褐紫乌头系可能是连接保山乌头系和短柄乌头系的“桥梁”,而准噶尔乌头系更靠近保山乌头系。(2)显柱乌头系set.Stylosa是以含大茴香酸酯基的乌头碱型二萜生物碱以及塔拉萨敏和查斯曼宁胺醇类为主的类群,是块根较大的“大乌头”的主要来源,具有很大的毒性。兴安乌头系ser.Ambigua以含大茴香酸酯基的乌头碱型和原始胺醇类如塔拉萨敏、尼奥灵等二萜生物碱为主。蔓乌头系ser.Volubilia是以含大茴香酸酯基/苯甲酸酯基的乌头碱型和塔拉萨敏胺醇类以及高度进化的乌头碱型二萜生物碱为主的中间过渡类群。乌头系ser.Inflata以含15-羟基的单酯、双酯或多酯以及胺醇类鸟头碱型二萜生物碱为主,且酯基中无大茴香酸酯基,此系是草乌的主要植物来源,具有很大的毒性,应十分慎用。这些系可能代表乌头亚属进化的类群。其中显柱乌头系与兴安乌头系可能较近缘。蔓乌头系可能是连接显柱乌头系/兴安乌头系与乌头系的中间类群。另外,保山乌头系、短柄乌头系和准噶尔乌头系可能是直接向显柱乌头系、蔓乌头系和乌头系过渡的较为原始的类群。(3)岩乌头系set.Racemulosa从化学分类角度来看是一个特殊的类群,支持其独立成一个分支。其化学特征以牛扁碱型和乌头碱型的胺醇二萜生物碱如牛扁碱、异塔拉萨亭定和C20-二萜生物碱为主。如果单纯从化学成分来看,它与牛扁亚属植物似乎有一定关系。  相似文献   

13.
The genus Gaultheria has been classified into ten sections (one with two subsections) and 22 series of which five are new combinations and 21 are new taxa. Seven of these sections are composed primarily of solitary flowered species and the other three sections of racemose species. About half of the species of the genus are included in section Brossaea. A summary of the classification is here presented.  相似文献   

14.
讨论了Clematis eriopoda Maxim.和sect.Atragenopsis Boiss.的地位,认为这二分类群均应成立;描述了2新种,1新变种;过去长期被归并的卷萼铁线莲C.tubulosa得到恢复;Clematisheracleifoliavar.ichangensis被转移改作卷萼铁线莲的变种;首次给出光叶铁线莲Clematisglabrifolia的果实的形态描述。  相似文献   

15.
The pollen morphology of forty taxa of the genus Nepeta L. was studied and documented in detail using light microscopy (LM) and scanning electron (SEM) microscopy in this study. Nepeta L. pollen grains are small to large (P = 18.64–63.46 μm, E = 15.62–46.33 μm), suboblate to perprolate (P/E = 0.86–2.09) in shape and hexacolpate (very rarely tetracolpate) with granular membranes. Alternate position of colpi occurs in six Nepeta taxa, N. nuda ssp. glandulifera, N. concolor, N. crinita, N. congesta var. cryptantha, N. stricta var. stricta and N. sibthorpii ssp. tumeniana. In examinations of exine ornamentation with SEM, two types of pollen grains were recognized: (1) type I, with microreticulate sculpture; and (2) type II with bireticulate sculpture, type I and II to be divided into two and five subtypes, respectively. In the two taxa with microreticulate pattern, N. pilinux and N. sulfuriflora, a tendency towards a bireticulum could be recognized due to traces of secondary tectal connections. The bireticulate exine ornamentation is characterized with varying characteristics of the primary muri and secondary reticulum. Pollen morphology within the genus is compared with infrageneric relationships.  相似文献   

16.
A palynological study of the genus Mentha L. (Lamiaceae)   总被引:1,自引:0,他引:1  
The pollen morphology and exine structure of 10 Mentha L . species were investigated using light microscopy and scanning electron microscopy. The pollen grains of all 11 species were hexazonocolpate with granular membranes and a circular amb, varying in shape from prolate-spheroidal to suboblate. Different colpus shapes were recognized in M . ×  dumetorum . The exine was bireticulate in section Pulegium , and reticulate in section Menthae . A correlation was found between pollen size and chromosome number. The results indicate that the pollen characters of the genus Mentha are valuable for taxonomic applications and may be useful for classification.  © 2008 Uludag University. Journal compilation © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 141–154.  相似文献   

17.
陕西毛茛科一新记录属—扁果草属   总被引:5,自引:0,他引:5  
中国毛茛科扁果草属植物有 2种 ,1种为东北扁果草 (Isopyrum manshuricumKom.) ,分布于东北 ;一种为扁果草 (Isopyrum anemonoides Kar.et Kir.) ,分布于甘肃南部、青海、新疆、西藏等省。陕西无分布记载。笔者于 1 999年在秦岭主峰太白山进行巴山冷杉林群落学研究中于 3个不同地点采集到扁果草属扁果草植物标本 3份 (现收藏于西北农林科技大学森林生态研究室 ) ,系陕西首次发现 ,予以报道。1 .扁果草Isopyrum anemonoides Kar.et Kir.In Bull.Soc.Imp.Not.Mosc.1 5:1 3 5.1 84 2 ;Icon.Corm.Sin.1 :670 .f.1 3 40 .1 972 ;Fl.Tsinl…  相似文献   

18.
Morphological and karyological investigations as well as crossing experiments were carried out withR. cacuminis, R. crenatus, andR. alpestris. A key is presented including all 6 taxa of theR. alpestris-group. Ecological and geographical data for the Balkan Peninsula are also presented.R. cacuminis is diploid with 2n = 16 chromosomes as all taxa of the group, its karyotype exhibits no statistically significant differences to those from the 5 other taxa. In crossing experiments betweenR. cacuminis andR. alpestris, no hybrids could be obtained, whereas those betweenR. cacuminis andR. crenatus were slightly successful. According to its morphology, geographical distribution, and crossing behaviour,R. cacuminis is closely related toR. crenatus, and probably has originated fromR. crenatus by quantum speciation.  相似文献   

19.
Ranunculus L. represents the largest genus within Ranunculaceae, comprising more than 600 species with a worldwide distribution. However, there are still many gaps in our knowledge of the infrageneric taxonomy and evolution of Ranunculus. In this regard, intraspecific variation of the polyploid complex Ranunculus parnassiifolius remains under discussion. To reconstruct the biogeographical history of the polyploid complex R. parnassiifolius, 20 populations distributed throughout the Cantabrian Mountains, Pyrenees, and Alps were investigated. Phylogenetic studies were based on nuclear internal transcribed spacers (ITS) and plastid (rpl32‐trnL, rps16‐trnQ) sequence data, analysed using Bayesian approaches as well as the evolution of morphological characters. Additionally, biogeographical patterns were conducted using statistical dispersal–vicariance analysis. The analyses presented here support the recognition of two evolutionary independent units: R. cabrerensis sensu lato (s.l.) and R. parnassiifolius s.l. Furthermore gradual speciation depending on the biogeographical territory is proposed, and optimal reconstructions have probably favoured the ancestor of Ranunculus parnassiifolius as originating in the Iberian Peninsula. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 107 , 477–493.  相似文献   

20.
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