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1.
Clematis sect. Atragene is revised in this paper based on the examination of a large number of herbarium specimens, extensive field observations, and morphometric analyses. Brief taxonomic history and geographical distribution of the section are given, the relationships among the species are discussed, and the evolutionary trends of some characters in the section are evaluated. The staminodes of the plants in this section may have evolved from the outer stamens with petaloid filaments and gradually disappearing anthers. Subsequently, they may have evolved in two different ways. One possibility is that the staminodes elongate and become lanceolate, as long as sepals, and their apices turn into attenuate. The other is that the staminodes are spathulate, but not elongating, as long as stamens, and their apices turn into retuse from obtuse and rounded. The evolutionary trend of sepals may be from thin to thick in texture, and the veins from non-prominent to prominent. As a result, five new series are established and nine species, two subspecies and nine varieties (including three new ranks) are recognized in this section. An identification key is provided, and each taxon is described and illustrated. Clematis sibirica and Clematis ochotensis are treated as subspecies of Clematis alpina due to their subtle differences and lack of, or few, overlapping distributions. Clematis fusijamana and Clematisfauriei are recognized as varieties of C. alpina ssp. ochotensis for the continuous variation of the velutinous strips on the sepal margins. Clematis iliensis is treated as variety of C. alpina ssp. sibirica for the continuous variation of leaf division types. Extensive variations in sepal color and basal caruncle size support degrading Clematis chiisanensis as a variety of Clematis koreana. The North American ser. Occientales may be primitive, whereas ser. Macropetalae may be the most advanced taxon in this section. Ser. Alpinae and ser. Koreanae are closely related to each other. However, the systematic position of ser. 相似文献
2.
对毛茛科铁线莲属Clematis
L.的单性铁线莲组sect. Aspidanthera Spach s.l.进行了全面修订,确定此组共含72种和15变种,这些种被归类于6个亚组中,其中包括首次描述的1系、5种和2变种,以及做出的2新等级.对单性铁线莲组的分类学简史和地理分布做了介绍.写出了组、亚组、系的形态特征和地理分布,分亚组检索表及各亚组的分种检索表;以及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.在研究了此组全部种类的标本之后,观察到此组几个重要形态特征的演化趋势(1)萼片在数目上由4枚演变到8枚,在开展方向上由平展到直上展,在形状上由长圆形到狭条形,在长度上由比雄蕊稍长到2-4倍长于雄蕊,其卷叠式由镊合状到次生的覆瓦状;(2)花药药隔顶端由不具突起到具短或长的突起;(3)雌花退化雄蕊的数目由多数到定数、少数,以至完全消失;(4)花序自当年生枝的叶腋发生演变到与数叶同自老枝的一腋芽中发出.根据上述演化趋势推断本组各亚组间的亲缘关系如下subsect.
Dioicae (34种,广布于北美洲和南美洲)的花构造(萼片4,镊合状排列,平展,通常呈长圆形,稍长于雄蕊或近等长,外面边缘被短绒毛;雄蕊花药呈长圆形,药隔顶端无突起;雌花具多数退化雄蕊;花序自当年生枝的叶腋发出)与具两性花的威灵仙组欧洲铁线莲亚组sect.
Clematis subsect. Clematis 的花极为相似,区别主要在于本亚组的花为单性,由此判断subsect.
Dioicae可能是单性铁线莲组sect. Aspidanthera的原始群,源出于欧洲铁线莲亚组.本组的第二亚组subsect.
Lasianthae(2种,分布于北美西南部)与subsect. Dioicae
在亲缘关系上极为相近,区别只在于其花序或具花当年生枝与数叶一同由老枝的一个腋芽中发出,此亚组当是从subsect.
Dioicae衍生出的一个小群.第三亚组subsect. Microphyllae(7种,特产澳大利亚)也与subsect.
Dioicae相近缘,但此亚组的萼片变狭长,多呈条形或狭条形,常2-4倍长于多少变短的雄蕊,雌花的退化雄蕊数目变少,16-2枚,根据这些进化特征,推测此亚组也源出于subsect.
Dioicae.第四亚组subsect. Aristatae (16种,分布于澳大利亚、新几内亚及邻近岛屿)与subsect.
Microphyllae 在亲缘关系上相近,但本亚组的花药药隔顶端具短或长的突起而不同,根据此进化特征,推测本亚组系由后者演化而出.第五亚组subsect.
Hexapetalae (11种,特产新西兰)的花构造与分布于澳大利亚的subsect.
Microphyllae相似,但其萼片为覆瓦状排列,外面边缘不被短绒毛,在多数种多于4枚,为5-8枚而不同.据Godley
的研究,本亚组中的C. afoliata的花有4枚萼片,排成2轮,每轮的2枚萼片均为近镊合状排列;另外,在C.
paniculata花的6枚萼片中,4枚为覆瓦状排列,其他2枚有时内向镊合状排列.从上述情况可见此亚组的萼片覆瓦状卷叠式可能是由镊合状卷叠式演变而来的一种次生现象,并由此推测,此亚组可能与subsect.
Microphyllae相同,也源自美洲的subsect.Dioicae.最后一个亚组subsect.
Insidiosae(2种,特产马达加斯加)的雌花萼片直上展,退化雄蕊完全消失,具有这些进化特征,当是单性铁线莲组的进化群,可能源出自具定数或少数退化雄蕊的subsect.
Microphyllae. 相似文献
3.
4.
After examining a large number of type and authoritative specimens of Schizophragma Siebold & Zucc., S. elliptifolium C. F. Wei and S. integrifolium var. glaucescens Rehder were reduced to synonyms of S. hypoglaucum Rehder and S. integrifolium f. cordatum S. Y. Wang was reduced to synonym of S. corylifolium Chun. Schizophragma crassum var. ellipticum J. Anthony was treated as the correct name of S. crassum var. hsitaoanum (Chun) C. F. Wei. The name S. integrifolium var. minus Rehder is reinstated. The taxonomic treatment is supported by leaf epidermal characters. 相似文献
5.
Microtropis macrocarpa C.Y. Cheng & T.C. Kao has been treated as a synonym of Microtropis macrophylla Merr. & Freeman in most taxonomic reports in China. According to our study, M. macrocarpa is an independent species endemic to Yunnan, China. Microtropis macrophylla and Microtropis pachyphylla Merr. & Freeman should be treated as synonyms of Microtropis longifolia Wall. ex Kurz. M. macrocarpa is also identified as a critically endangered species, CR B lab (i,ii,iii,v), based on the IUCN Red List Categories and Criteria. The foliar surface, anther and pollen structures were also observed with a scanning electron microscope. 相似文献
6.
Jinlong LIU Natalia A.ANANJEVA Marina A.CHIRIKOVA Konstantin D.MILTO Xianguang GUO 《亚洲两栖爬行动物研究(英文版)》2014,(1):12-25
The rapid racerunner,Eremias velox,is a widely distributed lizard from the northern Caucasus across entire Central Asia eastward to China.It is increasingly common to accept E.velox as a species complex in its entire range.To date,published morphological and molecular systematic hypotheses of this complex are only partially congruent,and its taxonomic status and evolutionary history are still far from clear.The mitochondrial cytochrome b gene and12S rRNA sequences were used to evaluate the taxonomy of this complex,with particular attention to the phylogenetic placement of populations in northwestern China.Examination of the phylogenetic analyses recovers seven distinct,biogeographically discrete,and well-supported clades,revealing genetically identifiable populations corresponding to some previously morphology-defined subspecies.Chinese E.v.roborowskii appears to have split from other Central Asian rapid racerunner lizards well before differentiation occurred among the latter taxa.Specifically,we corroborate that there are two subspecies occurring in China,i.e.,E.v.velox and E.v.roborowskii.We recommend a novel subspecific status for the phenotypically and genetically distinct populations in southern Aral Sea region of Uzbekistan previously assigned to E.v.velox.Finally,each of the three independently evolving lineages from Iranian Plateau should be recognized as three species new to science under the general lineage concept. 相似文献
7.
A new species, Leptolalax laui sp. nov. is described based on specimens collected from Hong Kong and Shenzhen City, Guangdong Province, China. The new species can be distinguished from other known congeners by morphological and molecular data. The new species is characterized by the following characters: 1) small size (adult males SVL 24.8.1 mm-26.7 mm); 2) near immaculate creamy white chest and belly; 3) broad lateral fringes on toes; 4) head longer or as long as wide; 5) distinct dark brown spots in flank; 6) moderate dermal fringes on fingers; 7) brown or reddish-brown dorsum with fine round scattered tubercles; 8) thin traverse brownish-grey bars on the dorsal surface of tibia and lower arms; 9) longitudinal ridges under toes not interrupted at the articulations. 相似文献
8.
9.
Populations of Thismia tentaculata (Burmanniaceae tribe Thismieae) are described and illustrated from Tai Mo Shan in Hong Kong, southern China. This represents the first report of the genus and tribe from continental China. 相似文献
10.
Qing-Song Zhou Yu-Qiang Xi Fang Yu Xu Zhang Xue-Jun Li Chun-Lai Liu Ze-Qing Niu Chao-Dong Zhu Ge-Xia Qiao Yan-Zhou Zhang 《Entomologia Sinica》2014,(3):363-373
Aphis glycines Matsumura is an important pest of soybean in Asia and North America. Hymenoptera parasitoids play a key role in the control of the soybean aphid. Thecorrect identification of parasitoids is a critical step that precedes the assessment of their potential biological control agents. Accurate identification of the majority of the speciesattacking the soybean aphid often requires elaborate specimen preparation and expert taxonomic knowledge. In this study, we facilitated the identification of soybean aphidparasitoids by applying a DNA barcoding approach following a preliminary morphological identification. We generated DNA sequence data from the mitochondrial COI gene andthe D2 region of 28S rDNA to assess the genetic variation within and between parasitoid species emerging from the soybean aphid in China. Fifteen Hymenoptera parasitoid speciesbelonging to 10 genera of five families were identified with little intra-specific variation (0.09% ± 0.06% for 28S and 0.36% ± 0. 18% for COI) and large inter-specific divergence(30.46% ± 3.42% for 28S and 20.4% ± 1.20% for COI). 相似文献
11.
The taxonomy of Lepisorus (J. Sm.) Ching sect. Lepisorus in China was revised based on herbarium specimen examinations, field observations, and microscopic study of rhizome scales, soral paraphyses, leaf epidermis and spores. As a result nine species were recognized: Lepisorus macrosphaerus (Baker) Ching, L. asterolepis (Baker) Ching, L. marginatus Ching, L. kuchenensis (Y. C. Wu) Ching, L. megasorus(C. Chr.) Ching, L. kawakamii (Hayata) Tagawa, L. subsessilis Ching & Y. X. Lin, L. affinis Ching and L. nudus (Hook.) Ching. Lepisorus kawakamii (Hayata) Tagawa was reinstated; L. gyirongensis Ching & S. K. Wu and L. longus Ching were reduced to synonyms of L. nudus and L. affinis respectively. The subdivision of L. macrosphaerusis was not accepted. Rhizome scales and paraphyses are the most useful characters for species delimitation as well as for infrageneric classification. Characteristics of the leaf epidermis and spore ornamentation are usually stable and thus of great significance in understanding the relationships among groups within the genus. 相似文献
12.
对毛茛科Ranunculaceae铁线莲属Clematis的菝葜叶铁线莲组sect. Naraveliopsis进行了全面修订, 确定此组共含21种1亚种和1变种; 写出此组的分类学简史和地理分布, 并讨论了此组在铁线莲属中的系统位置; 将此组划分为3亚组, 写出分亚组、分种检索表, 以及各种植物的形态描述、地理分布、生长环境等, 并附有多数种的墨线图。根据对此组植物形态特征的分析, 观察到以下重要演化趋势: (1)叶从单叶演变到二回羽状复叶或二回三出复叶; (2)花从两性到单性, 从无退化雄蕊到有退化雄蕊; (3)雄蕊从无毛到有毛; (4)药隔突起从短(0.5-0.7 mm)到长(8.5-10 mm)。根据上述演化趋势,花两性、雄蕊被毛、退化雄蕊存在的荔波铁线莲亚组subsect. Liboenses(1种,特产贵州荔波)和花由两性变为单性的亚组subsect. Macgregorianae(2种,特产菲律宾)被认为是菝葜叶铁线莲组的进化群。在原始的菝葜叶铁线莲亚组subsect. Smilacifoliae(花两性,雄蕊无毛; 18种,广布亚洲热带地区)中,具单叶,花无退化雄蕊,药隔突起较短的菝葜叶铁线莲C. smilacifolia和滇南铁线莲C. fulvicoma被认为是较原始的种,而具三出复叶和退化雄蕊的C. vietnamensis和丝铁线莲C. loureiriana,以及具羽状复叶和长药隔突起(长达10 mm)的C. papillosa等3种则被认为是此亚组的进化种。自中南半岛北部山地向西经云贵高原南部至喜马拉雅东部山区集中分布有菝葜叶铁线莲组的13种植物,这一山区地带被认为是此组的分布中心。在此山区地带中,菝葜叶铁线莲的分布区和滇南铁线莲的分布区重叠部分的山区可能是此组的起源中心。 相似文献
13.
铁线莲属茴芹铁线莲组修订 总被引:3,自引:1,他引:3
对毛茛科铁线莲属Clematis L.的茴芹铁线莲组sect.Pseudanemone进行了分
类学修订,确定此组包含约16种、3亚种和2变种;写出了此组的分类学简史和地理分布,讨论
了此组在铁线莲属的系统位置;将此组划分为3系,写出了分系、分种检索表,以及各种植物
的形态描述、地理分布、生长环境等,并附有多幅插图。(2)本组植物的花具4枚平展的萼
片,雄蕊花丝条形,被柔毛。在铁线莲属中,这样的花构造与对枝铁线莲组sect.Brachiata
e的花较为相似。但本组植物为直立的亚灌木或小灌木,萼片常部分镊合状排列,部分覆瓦状
排列,通常呈卵形或宽卵形,内面常密被短柔毛或短绒毛,雄蕊花药通常条形,较长,常长
达5-9.5mm。因为具有这些较为特化的特征,此组遂比对枝铁线莲组为进化(在对枝铁线莲组
,所有的种均为木质藤本植物,萼片4枚镊合状排列,通常呈长圆形,内面常被短柔毛,但不
被短绒毛,雄蕊花药通常长圆形,较短,长1-3mm),可能由后者演化而来,因此,茴芹铁线
莲组和对枝铁线莲组一样,也是属于铁线莲属中欧洲铁线莲演化干的一个成员。(3)如前所
述,本组的萼片常部分镊合状排列,部分覆瓦状排列。在铁线莲属中,绣球藤组sect.Cheir
opsis特产日本的单型亚组subsect.Williamsianae和单性铁线莲组sect.Aspidanthera特产新
西兰的亚组subsect.Hexapetalae的萼片卷叠式也有类似情况,这说明在铁线莲属中不同演化
干上出现的部分萼片呈覆瓦状排列的情况应当是次生的,而不是原初的现象。(4)根据萼片
的毛被和花药的长度,本组被划分为3系:第1系,茴芹铁线莲系ser.Pimpinellifoliae,是本
组的原始群,含7种,特产马达加斯加中亚山区,其特征为萼片薄纸质,内面无毛或多少疏被
短柔毛,花药条形或狭长圆形,长2.2-4mm。第2系,绒毛铁线莲系ser.Villosae,含3种,特
产非洲大陆中部及南部,其特征为萼片常较厚,呈纸质或亚革质,内面密被短绒毛或密短柔
毛,花药通常条形,有时狭长圆形,长2.5-4(-5)mm。第3系,黄果铁线莲系ser.Chrysoca
rpae,含6种,特产非洲大陆中部之南,其特征为萼片较厚,呈纸质或亚革质,内面通常被密
短柔毛或短绒毛,只1种无毛,花药条形,在多数种长5.8-7mm,在特产扎伊尔南部的C.kata
ngensis则长8-9.5mm,是茴芹铁线莲组中最长的花药。 相似文献
14.
(1)对毛莨科铁线莲属Clematis的铁线莲组sect.Viticella进行了分类学修订,确定此组包含13种,1亚种和2变种(包括2新种和1新变种等级),写出此组的分类学简史和地理分布;将此组划分为3亚组,4系,写出区分组下各级分类群的检索表,以及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。(2)特产我国东部的单型毛萼铁线莲亚组subsect.Hancockianae(花具4枚平展,不展宽的萼片,雄蕊无毛)被认为此组的原始群。铁线莲亚组subsect.Floridae(花具5-8枚平展,强烈展宽的萼片,雄蕊无毛,花粉具散孔)和湖州铁线莲亚组subsect.Viticellae(花具4枚渐升,多少展宽的萼片,雄蕊花丝常被缘毛,花粉具3沟)可能均由毛萼铁线莲亚组衍生而出。(3)在我国东部集中分布此组的3亚组,3系的8种,1亚种和1变种,这里是此组的分布中心,也可能是此组的起源中心。 相似文献
15.
铁线莲属威灵仙组修订 总被引:21,自引:11,他引:10
对铁线莲属铁线莲亚属 Clematis subgen. Clematis 中的欧洲铁线莲 C. vitalba L.演化干的原始群威灵仙组sect. Clematis 进行了全面修订,确定此组共含有73种和45变种。写出了威灵仙组的分类学简史及地理分布;对威灵仙组中各亚组的亲缘和主要区别特征以及铁线莲亚属欧洲铁线莲演化干中各群的亲缘关系进行了讨论。将威灵仙组分为5个亚组,写出了分亚组检索表和各亚组的分种检索表,以及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。在5亚组中,欧洲铁线莲亚组(钝萼铁线莲亚组) subsect. Clematis 为此组的原始群,其主要特征:藤本;小叶通常草质或纸质,通常边缘具齿,有时全缘;萼片4,外面的毛长1 mm以下;花药长圆形、椭圆形或狭长圆形,稀条形,药隔顶端不突起,稀稍突起。此亚组的瘦果两侧扁压,但多数不扁平,不具边缘,只在短毛铁线莲 C. puberula Hook. f. &; Thoms.强烈扁压,扁平,周围具宽边缘。在铁线莲属中,除短毛铁线莲外,特产朝鲜的 C. brachyura Maxim. (sect. Pterocarpa Tamura)也具有近似这种进化类型的瘦果。铁线莲组的其他4个亚组各含有较进化的特征,可能均自欧洲铁线莲亚组演化而出:单种的厚叶铁线莲亚组subsect. Crassifoliae (Tamura) Tamura为藤本;小叶革质,全缘,很像威灵仙亚组的小叶;雄蕊花丝皱缩,花药宽长圆形或长圆形。单种的长毛铁线莲亚组subsect. Baominianae (W. T. Wang) W. T. Wang为藤本;小叶纸质,具齿;花大,具6枚萼片;萼片外面的毛长1.6-3 mm; 花药长圆形。棉团铁线莲亚组subsect. Angustifoliae 的主要特征:茎直立;花常具5-6枚萼片。威灵仙亚组subsect. Rectae Prantl的主要特征:藤本,稀茎直立;小叶常革质,全缘,稀具齿;萼片通常4枚,稀较多,外面的毛长在1 mm以下;花药条形,有时狭长圆形,药隔顶端常突起。此亚组的威灵仙系ser. Rectae Prantl具有进化类型的瘦果,其瘦果强烈扁压,扁平,有膨胀的框状边缘。主要分类学处理为:(1)披针叶铁线莲 C. lancifolia Bur. &; Franch.、准噶尔铁线莲 C. songarica Bunge、 C. ispahanica Boiss.、银叶铁线莲 C. delavayi Franch.和 C. phlebantha Williams 5种过去被Tamura和其他学者与灌木铁线莲 C. fruticosa Turcz.等同置于灌木铁线莲组sect. Fruticella Tamura中,但这5种的花构造(萼片水平方向开展,白色,边缘不展宽;花丝条形或狭条形)与灌木铁线莲(萼片斜上方开展,黄色,在花开放后边缘展宽成狭翅;花丝较宽,条状披针形)不同,而与棉团铁线莲 C. hexapetala Pall.的花构造相似。据此,本修订将此5种从灌木铁线莲组移到威灵仙组的棉团铁线莲亚组subsect. Angustifoliae Tamura中。(2)在欧洲铁线莲群 C. vitalba group与威灵仙群C. flammula group之间有不少过渡类型,因此,这两个群不易区分。根据这种情况,本修订将这两个群作为亚组处理,同置于威灵仙组sect. Clematis 中,而未采用Tamura和Grey_Wilson将这两个群分别置于两个亚属中,以及Johnson将这两个群分别置于两个组中的分类学处理。描述了2新系、6新种和1新变种;建立了5个新等级。 相似文献
16.
对毛茛科铁线莲属Clematis L.的对枝铁线莲组sect. Brachiatae进行了全面修订,确定此组共含24种和4变种(包括2新种),写出了此组的分类学简史和地理分布,对其在铁线莲属中的系统位置和起源以及组下分类进行了讨论;还写出了组下分类群检索表,以及每系和每种植物的形态描述、地理分布、生长环境等,并附有多幅插图。本组各种的花构造相当一致:萼片4,镊合状排列,水平开展,白色,通常呈长圆形、卵形或披针形,只在2进化种呈宽椭圆形,外面边缘上密被短绒毛;雄蕊花丝狭条形,被柔毛,花药通常长圆形或狭长圆形,无毛,药隔顶端通常不突出;心皮密被柔毛。上述花构造与威灵仙组欧洲铁线莲亚组sect. Clematis subsect. Clematis 的花构造极为相似,与后者的区别仅在于本组被毛的雄蕊花丝。本组是在1992年由黄花铁线莲组sect. Meclatis (萼片4,通常向斜上方开展,黄色,卵形、长圆形或披针形;花丝由于下部变宽而呈狭披针形,被柔毛)中分出建立的,可能与黄花铁线莲组有亲缘关系,并可能同自威灵仙组欧洲铁线莲亚组演化而出。本组的叶变异较大,自单叶至三出复叶、1-3回羽状复叶,最后到3-4回羽状细裂,表现出一明显演化趋势。根据叶的上述特征,以及萼片形状,本组被划分为2系。第1系,对枝铁线莲系ser. Wightianae: 叶为单叶、三出复叶或1-2(-3)回羽状复叶,萼片呈长圆形至披针形,含22种,其中20种分布于科摩罗、马达加斯加、毛里求斯、非洲大陆和阿拉伯半岛西南部,另2种分别分布于印度南部和喜马拉雅山区西部。第2系,细裂铁线莲系ser. Dissectae: 叶3-4回羽状全裂,萼片呈宽椭圆形,含2种,特产马达加斯加。本组各种植物中具单叶的只有1种,即盒子草铁线莲C. actinostemmatifolia (特产科摩罗)。特产马达加斯加的伏毛铁线莲C. strigillosa和特产毛里求斯及马达加斯加的毛里求斯铁线莲C. mauritiana的叶全部为三出复叶。特产非洲大陆中部的扎伊尔铁线莲C. zaireensis的叶多数为三出复叶,有少数叶为具5枚小叶的羽状复叶;此种与产马达加斯加的伏毛铁线莲相近缘,但比后者进化,可能系由后者或后者的近缘种演化而来,并代表了非洲大陆对枝铁线莲组的原始类型,因为非洲大陆该组的其他13种均具1-2回羽状复叶。此外,特产印度南部的怀特铁线莲C. wightiana具1回羽状复叶,特产喜马拉雅山区西部的浓香铁线莲C. graveolens则具2-3回羽状复叶。根据上述,推测科摩罗、马达加斯加和毛里求斯这一群岛地区可能是对枝铁线莲组的起源中心。 相似文献
17.
对毛茛科铁线莲属Clematis的黄花铁线莲组sect. Meclatis进行了全面修订, 确定此属含13种和13变种(包括1新变种和2新变种等级); 写出了此组的分类学简史和地理分布, 并对其在铁线莲属中的系统位置和组内诸种的亲缘关系进行了讨论; 还写出了此组的分种、分变种检索表, 以及各种植物的形态描述、地理分布、生长环境等, 并附有各种的插图。此组的花构造与对枝铁线莲组sect. Brachiatae的近似, 与后者在亲缘关系上相近, 区别在于此组的萼片通常斜上方开展, 呈黄色, 被毛的花丝下部变宽, 呈狭披针形, 而在对枝铁线莲组, 萼片水平开展, 呈白色, 被毛的雄蕊花丝呈狭条形, 下部不变宽; 二组可能均起源于欧洲铁线莲组的sect. Clematis subsect. Clematis, 因此, 均应是隶属欧洲铁线莲亚属subgen. Clematis的成员。根据对此组植物形态特征的分析, 观察到以下演化趋势: (1)叶的颜色由于适应干旱气候, 由绿色变为灰绿色; (2)卵形或宽卵形、掌状分裂、边缘具齿的小叶可能是原始的特征, 而披针形或条形、不分裂、全缘的小叶是衍生的特征; (3)单独、顶生、只是花梗的花是由具花序梗和二苞片的聚伞花序发生减化(reduction)而衍生的; (4)萼片形状的演化趋势与小叶形状的演化趋势近似, 也由卵形演变到披针形或条形; (5)萼片内面无毛是原始现象, 而被毛则是衍生现象; (6)萼片顶端无突起是原始现象, 出现突起则为衍生现象; (7)花药形状由长圆形演变到狭长圆形和条形。根据上述演化趋势, 推测具较多原始特征的甘川铁线莲C. akebioides和甘青铁线莲C. tangutica为此组的原始种, 而具较多衍生特征的尾尖铁线莲C. caudigera和角萼铁线莲C. corniculata为此组的进化种。组成世界屋脊的青藏高原西缘、帕米尔高原和邻近山地集中分布有此组10种(包括7特有种), 当是此组的分布中心; 而甘川铁线莲和甘青铁线莲二种分布区的主要重叠部分所在的青藏高原东缘则可能是此组的起源中心。过去,一些铁线莲属专家将属于欧洲铁线莲组的C. ispahanica Boiss.和属于对枝铁线莲组的C. graveolens Lindl.误置于黄花铁线莲组中, 对此, 本文予以纠正。 相似文献
18.
对毛茛科铁线莲属Clematis的灌木铁线莲组sect. Fruticella进行了全面修订,确定此组共含5种、2 变种和3变型;对此组的分类学简史和地理分布做了介绍;写出本组2系的形态特征和地理分布,组下分类 群检索表,以及各种植物的形态描述、地理分布、生长环境等,并附有各分类群的3幅插图。根据花的构造 认为在铁线莲属中,灌木铁线莲组与黄花铁线莲组sect. Meclatis在亲缘关系上最为接近。二组拥有的共 同特征为: 花的4枚萼片呈黄色,斜上方开展;雄蕊花丝下部变宽,呈披针状条形。二组的区别为: 灌木铁 线莲组的萼片边缘在花开放后展宽成膜质狭翅,雄蕊无毛;而在黄花铁线莲组,萼片边缘不展宽,雄蕊花丝 被柔毛。本组5种的花构造一致;在其他营养器官形态特征方面观察到以下演化趋势: (1)叶由不分裂到羽 状全裂,由绿色到灰绿色,由狭菱状卵形到条形;(2)花序含数朵花,具花序梗和2苞片,生于当年生枝顶端, 到花数目减少到1朵,花序梗和苞片消失,花生于当年生枝的腋生短枝顶端。根据上述演化趋势认为灌木 铁线莲的模式变型C. fruticosa f. fruticosa (叶绿色,狭卵形或披针形;花序通常含数朵花,顶生于当年生枝 上)是本组的原始类型,其他种可能均源出于此类型。根据花序特征,本组被划分为2系。第1系,灌木铁线 莲系ser. Fruticosae,含4种,分布于我国黄土高原及相邻干旱地区,向北达蒙古戈壁荒漠,向南在甘肃越过 秦岭到达甘肃南部。在黄土高原北部及相邻的内蒙古西南部集中分布本系全部4种,这里是灌木铁线莲 组的分布中心。第2系,绿叶铁线莲系ser. Virides,含绿叶铁线莲C. viridis 1种,分布于我国横断山区北部的 高山灌丛草地。 相似文献
19.
WANG Wen-Tsai 《植物分类学报:英文版》2004,42(4):289-332
Clematis sect. Brachiatae is revised in this paper. Twenty-four species and four varieties are recognized. They are keyed, described, and illustrated in most cases, and classified into two series. Brief taxonomic history and geographical distribution of the section are given, and its systematic position and origin are discussed. A western Himalayan species, C. graveolens Lindl., which has long been misplaced in the C. orientalis group (sect. Meclatis), is transferred to sect. Brachiatae on the basis of its floral structure being identical with that of C. brachiata Thunb. and its allies. Two new combinations, sect. Brachiatae Snoeijer ser. Wightianae (W. T. Wang) W. T. Wang and ser. Dissectae (W. T. Wang) W. T. Wang, are made, and two species, C. zaireensis W. T. Wang and C. bowkeri Burtt Davy, are described as new. 相似文献