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1.
中国紫金牛属的分支分类学研究   总被引:2,自引:0,他引:2  
基于60个形态学性状,对中国广义报春花科(Primulaceae s.l.)紫金牛属(Ardisia)90个分类群的系统发育关系运用分支分析方法进行了分析。采用最简约性分析得到了100个同等简约树。50%多数规则一致树的分支结构与以前建立的紫金牛亚属划分系统基本一致。外类群酸藤子属、铁仔属、密花树属聚在分支树的最基部,紫金牛属为一单系类群。形态分支树的一致性指数和保持性指数和各分支内部支持率均较低,只在种与变种或亚种之间获得较高的支持率。高木亚属、腋序亚属、短序亚属、顶序亚属处于分支树较为基部的位置,推测这四个亚属的类群在紫金牛属中较为原始;圆齿亚属和锯齿亚属共同组成一大支,二者亲缘关系紧密,推测这两个亚属为该属中最为进化的类群。结合形态学对属内系统发育关系进行了讨论和推测了一些性状的演化趋势,以期为分类修订提供依据。  相似文献   

2.
翅果形态及其在槭树科分类与演化上的意义   总被引:12,自引:0,他引:12  
徐廷志   《广西植物》1996,16(2):109-122
槭树科(Aceraceae)是北温带分布的科,含2属,全世界约200种,中国是槭树科植物的现代分布中心。对槭树科翅果的专门研究尚未见报道。本文1、引用一套槭属翅果形态学术语;2、观察并描述75种械属植物的翅果;3、研究槭属16个组的翅果的17个可比性状,根据分枝系统分析法得出槭属各组的演化关系及趋势,这趋势与依据其花、叶等性状得出的演化关系基本上是一致的。  相似文献   

3.
基于93个形态形状,采用13个被子植物基部类群做为外类群,对49个单子叶植物科级分类阶元进行了分支系统学分析。经过简约性分析,得到了1684棵同等最大简约分支树。严格一致树的分支结构图表明:1)古草本类植物和单子叶植物是姐妹群关系;2)具有网状脉的类群,薯蓣科,菝葜科,百部科是单子叶植物的最基部类群。由于性状状态间存在着较多的平行和逆转进化,这在一定程度上影响了系统发育重建的准确性;所选择的性状状态之间的演化很可能是平行的、多次的或者是特化的状态,因此这样复杂的演化关系的探索关键在于找到一些能确切反映其系统演化关系的形态性状。目前很难通过简约化的形态分支分析来解开整个单子叶植物的起源和演化之谜。为了避开对系统学分析造成干扰的误导性状,形态数据结合DNA序列分析很可能是必需的。  相似文献   

4.
湘西北发现大片野生蜡梅林   总被引:5,自引:1,他引:4  
陈功锡  李菁  盛忠恒   《广西植物》1995,15(4):373-373
湘西北发现大片野生蜡梅林陈功锡,李菁,盛忠恒(吉首大学生态研究所,湖南416000)蜡梅(Chin。onanthuspraecox(L.)Link)系指蜡梅科蜡梅属的落叶灌木植物,为我国特产,世界著名的园林观赏树种。冬季开花,花色清新淡雅,花香芳郁宜...  相似文献   

5.
槭属(Acer L.)属槭树科(Aceraceae),200种,分布于亚、欧、北美和非洲北缘。本文研究了槭属的系统演化、地理分布、起源与扩散。认为:(1)槭树科与无患于科关系密切,槭属是槭树科2属中较进化的类群。(2)在原始而典型的槭属植物的基础上,槭属沿花的各部减少,有的器官甚至向完全退化的方向演化,但也有少数向增加数目的方向特化。(3)讨论了槭属4亚属23组的演化趋势,并绘制出其系统演化图。(4)槭属起源于侏罗纪的中国四川东部、湖北、湖南及其邻近地区,并向西、东北和南方扩散而进入西亚、欧洲、非洲北缘、北美洲和马来半岛至印尼。  相似文献   

6.
槭属的系统演化与地理分布   总被引:23,自引:3,他引:20  
槭属(AcerL)属槭树科(Aceraceae),200种,分布于亚、欧、北美和非洲北缘。本文研究了槭属的系统演化、地理分布、起源与扩散。认为:(1)槭树科与无患子科关系密切,槭属是槭树科2属中较进化的类群。(2)在原始而典型的槭属植物的基础上,槭属沿花的各部减少,有的器官甚至向完全退化的方向演化,但也有少数向增加数目的方向特化。(3)讨论了槭属4亚属23组的演化趋势,并绘制出其系统演化图。(4)槭属起源于侏罗纪的中国四川东部、湖北、湖南及其邻近地区,并向西、东北和南方扩散而进入西亚、欧洲、非洲北缘、北美洲和马来半岛至印尼。  相似文献   

7.
红豆杉科植物RAPD分析及其系统学意义   总被引:23,自引:2,他引:21  
王艇  黄超 《西北植物学报》2000,20(2):243-249
利用随机扩增多态性DNA(RAPD)技术分析了红豆杉科(Taxaceae)红豆杉属(Taxus)、白豆杉属(Pseudotaxus)、穗花杉属(Amentotaxus)和榧树属(Torreya)的6种植物:红豆杉(Taxus chinensis (Pilger)Rehd)、南方红豆杉(Taxus chinensis var.mairei(Lemee etLevl.)Cheng etMaireYew  相似文献   

8.
中国树蟋属的研究:直翅目:树蟋科   总被引:1,自引:0,他引:1  
中国树蟋属的研究(直翅目:树蟋科)刘宪伟,殷海生,夏凯龄(中国科学院上海昆虫研究所,上海200025)关键词树蟋科;树蟋属;新种;中国树蟋属Oecanthus隶属蟋蟀总科Grylloidea树蟋科()ecanthidae。本属体细长而纤弱,体色一般呈...  相似文献   

9.
选用锦鸡儿属在秦岭和秦岭以北的20余种和59个形态性状作为分析基础。表征图和分支图共同提示出羽状和掌状叶类群形成两大类。分支图说明了树锦鸡儿C.arborescens和柄荚锦鸡儿C.stipitata等为原始类群。沿树锦鸡儿的分布区,本属植物向西和西南方向适应辐射成以温度和降水为主导因子的生态序列:(1)森林种→森林草原种→草原种→荒漠种,森林种→高寒山地种;(2)湿润地带→亚湿润地带→半干旱地带  相似文献   

10.
蜡梅科植物的叶表皮特征及其在分类上的意义   总被引:9,自引:1,他引:9       下载免费PDF全文
用扫描电镜和光学显微镜观察了蜡梅科3属5种植物成熟叶片远轴面的表皮特征,认为这些表皮细胞特征和气孔器特征在分类上有比较重要的意义。蜡梅属、夏蜡梅属和美国蜡梅属植物的叶表皮毛均为单细胞毛、非腺毛,上、下表皮细胞均为多边形,垂周壁呈深波状,气孔器均为平列型.这三个属的亲缘关系密切,应该归属于同一个大类群-蜡梅科。这为蜡梅属、夏蜡梅属、美国蜡梅属的分类提供了有用的性状特征。这三个属气孔器的演化趋势为:气孔器在保卫细胞的两极无"T"型加厚到有"T"型加厚,气孔器由单层外拱盖到双层外拱盖.  相似文献   

11.
中国菌蚊科属的系统发育关系分析(双翅目:眼菌蚊总科)   总被引:1,自引:1,他引:0  
采用Hennig 86程序,以柄菌蚊科和喙菌蚊科代表种为外群,选取48个特征,使用mhen-nig^*和bb^*指令在586微机上运算,首次对菌蚊科中5亚科28属的28种进行支序分析,探讨各分类单元系统发育关系。结果表明:菌蚊亚科与滑菌蚊亚科的亲缘关系较近,二者互为姐妹群,粘菌蚊亚科属于原始类群;菌蚊亚科为5个亚科中的进化类群;邻菌蚊亚科可能为并系群;真菌蚊亚科是介于邻菌蚊亚科与菌蚊亚科之间的类群。  相似文献   

12.
论山毛榉科植物的系统发育   总被引:10,自引:2,他引:8  
本文运用分支分类学方法,对山毛榉科植物进行了系统发育的分析。山毛榉科作为单元发生群包括柯属、锥属、粟属、三棱栎属、水青冈属和栎属。桦木科和南山毛榉属被选择作为外类群。对大量的性状进行评估之后,选择了25对性状作为建立数据矩阵的基本资料。性状极化以外类群比较为主,同时也采用了化石证据和通行的形态演化的基本原则。数据矩阵由7个分类群、2个外类群和25个性状组成。采用最大同步法、演化极端结合法和综合分析法对该数据矩阵进行了分析。在得到的3个树状分支图中按照最简约的原则,选出演化长度最短的谱系分支图作为本文讨论山毛榉科属间的系统演化关系的基础。关于山毛榉科植物的系统发育,作者的观点如下:(A)现存的山毛榉科的6个属形成了4条平行进化的分支路线,它们分别被处理作4个亚科,即:栗亚科,三棱栎亚科,水青冈亚科和栎亚科;(B)平行进化是山毛榉科植物系统发育过程中的主要形式。生殖过程中的一些特征,如:果实第二年成熟,胚珠通常败育等,是影响山毛榉科植物属间基因交流的主要原因。在现存的山毛榉科植物中,柯属是最原始的类群。三棱栎属和锥属的起源也较早,而栗属、水青冈属和栎属是特化的类群。  相似文献   

13.
In the present paper,both cladistic analysis and phenetic analysis were conducted to evaluate the phylogenetic relationships of the Taxodiaceae based on an extensive literature review and study of herbarium. In the cladistic analysis,the Sciadopityaceae was chosen as outgroup.The polarity of characters was determined mainly according to outgroup comparison,fossil evidence and generally accepted viewpoints of morphological evolution.By the result of compatibility analysis,character 2(leaf type),which possessed a much higher coefficient than others whether or not its polarity was altered,was deleted. Finally,a data matrix consisting of all the extant nine genera and 24 characters was analyzed using Maximal Same Step Method,Synthetic Method,Evolutionary Extremal Aggregation Method and Minimal Parallel Evolutionary Method,and four cladograms were generated,of which only the most parsimonious one (Fig.1)was presented for discussion. The cladogram shows that the Taxodiaceae are assorted along five lines of evolution: 1)Metasequoia;2)Sequoiadendron,Sequoia;3)Cryptomeria;4)Glyptostrobus and Taxodium;5)Cunninghamia,Athrotaxis and Taiwania. Ten genera(including Sciadopitys)and 59 characters were used in the phenetic analysis.The phenogram(Fig.2)indicates that Sciadopitys is a very distinct group with remote affinity to the other genera,and the Taxodiaceae are divided into four groups:1)Sequoia,Sequoiadendron;2)Athrotaxis,Cunninghamia and Taiwania;3)Cryptomeria,Glyptostrobus and Taxodium;4)Metasequoia. Based primarily on the result of cladistics,with reference to that of phenetics,the main conclusions were drawn as follows:(1)Generic relationships:Cryptomeria should be considered the most primitive genus in the extant groups of the Taxodiaceae. Glyptostrobus and Taxodium, close to Cryptomeria, are sister taxa and relatively primitive groups. Sequoiadendron and Sequoia are closely related and intermediate advanced. Metasequoia is a more or less isolated taxon, relatively close to Sequoiadendron and Sequoia. Cunninghamia. Athrotaxis and Taiwania might represent a single lineage and form a very advanced group, of which Taiwania may be the most specialized. (2) Systematic treatments: The authors support the viewpoint that Sciadopitys should be treated as an independent family, and suggest that the Taxodiaeae should be divided into five tribes. Systematic arrangements are as follows: Taxodiaceae Warming Trib. 1. Cryptomerieae Vierhapper Gen. 5. Sequoia Endl. Gen. 1. Cryptomeria D. Don Trib. 4. Metasequoieae Pilger et Melchior Trib. 2. Taxodieae Benth. et Hook. Gen. 6. Metasequoia Miki ex Hu et Cheng Gen. 2. Glyptostrobus Endl. Trib. 5. Cunninghamieae Zucc. Gen. 3. Taxodium Rich. Gen. 7. Cunninghamia R. Br. Trib. 3. Sequoieae Wettstein Gen. 8. Athrotaxis D. Don Gen. 4. Sequoiadendron Buchholz Gen. 9. Taiwania Hayata  相似文献   

14.
Abstract— The classical view of rust phylogeny is that rusts found on ferns and conifers are primitive, while rusts that parasitize angiosperms are advanced. This belief was based on the theory that primitive hosts harbor primitive parasites; that is, it assumed coevolution (co-speciation) of hosts and parasites. A cladistic analysis of 30 genera and 28 characters representative of the major patterns of rust fungi diversity is presented. The results of this analysis suggest that tropical short-cycle rusts on angiosperms form the cladistically basal group of rusts, while the rusts on conifers and ferns (Melampsoraceae sensu lato ) form a nested terminal clade. These results suggest that rusts and their hosts have not undergone a long period of parallel cladogenesis (co-speciation); host transfer has probably been at least as frequent as co-speciation. The cladograms indicate evolutionary trends of spore stages and life history: urediniospores evidently preceded the evolution of aeciospores and pycniospores within Uredinales, and heteroecism is a derived condition which evolved at least several times. This study stresses the importance of making use of independent cladistic analyses of both host and parasite in order to test assumptions of coevolution and host transfer.  相似文献   

15.
龙胆属的系统发育分析   总被引:2,自引:0,他引:2  
本文运用支序分类的原理和方法,对龙胆科龙胆属的属下等级进行了重新归类和系统发育分析。龙胆属是一个单系群,以3项近裔共性为归类依据。性状分析作了性状同源性分析和性状极性分析。性状极化主要以外类群比较、性状相关性及染色体资料为依据,其它方法,如生物重演律原则、地理递进原则以及孢粉形态等也被结合使用。分析结果,双蝴蝶属和蔓龙胆属被选择为外类群,71个性状被选择作为建立数据矩阵的基本资料。使用PAUP程序对矩阵进行了运算,得到4个最简约的谱系分支图,它们均具一致性系数0.637,支序长度为160步,f-比值范围为0.179~0.189,其中具最低f-比值的图被选作为类群归类和讨论亲缘关系的基础。在支序图上龙胆属归为15个组;其中5个组又划分为系,共包括23个系,其余组为单型组,故共有33个属下类群。一个严格的一致性谱系分支图总结了所有的一致点,从而支持了支序分析的结果。  相似文献   

16.
A cladistic, phylogenetic analysis of the Retiolitidae, using 18 genera and parataxa and 23 characters, reveals that two distinct clades can be recognized within this family, as well as a primitive stem-group that includes the genus Pseudoretiolites . One of the derived clades includes Pseudo-plegmatograptus, Stomatograptus and Retiolites , which are assigned to the revised subfamily Retiolitinae. The other derived clade, the early part of which shows a paraphyletic relationship, includes the remaining known genera Rotaretiofites s.l., Paraplectograptus s.l., Sokolovograptus, Plectograptus, Agastograptus, Spinograptus, Gothograptus, Eisenackograptus, Neogothograptus, Semiplectograptus, Plectodinemagraptus and Holoretiolites . These genera are all included within an expanded Plectograptinae. The biostratigraphic distribution of these taxa suggests that these two clades diverged from a Pseudoretiolites-like ancestor in mid-Aeronian time.  相似文献   

17.
A cladistic analysis of Lophopidae was performed, using 73 observed morphological characters and 41 taxa. This analysis involved 36 genera belonging to the Lophopidae family and 5 outgroups. For a better understanding of the selected characters some illustrations are provided. The most parsimonious cladograms obtained show that the Lophopidae cannot be considered as a monophyletic lineage unless two genera are withdrawn from this family: Hesticus Walker, 1862, and Silvanana Metcalf, 1947. The systematic position of these two genera remains uncertain. They cannot yet be included in another family of Fulgoromorpha. A cladistic analysis of each of the 19 remaining Fulgoromorphan families must be performed first. A new family could be created for these two genera, but not before we are sure that these two genera are in no way members of an existing family. The outgroup problem is discussed. The monophyletic lineage represented by the Lophopidae can be divided into four natural groups: Carriona+, Makota+, Sarebasa+, and Bisma+. When a cladistic analysis is completed using a data matrix without characters linked to females, the cladogram obtained presents a disrupted basal resolution. Female characters appear to bring a phylogenetic signal important basally in the evolution of the Lophopidae but also apically, directly between the relationships of some genera. A similar analysis, using a matrix without characters linked to males, provides a phylogeny disrupted between the groups that form the Lophopidae and in the basal resolution in these groups. The respective impacts of the genitalic characters are discussed in relation to sexual selection conflict.  相似文献   

18.
A phylogeny of sparoid fishes (Perciformes, Percoidei) based on morphology   总被引:2,自引:0,他引:2  
 The putative percoid superfamily Sparoidea includes the Nemipteridae, Lethrinidae, Sparidae, and Centracanthidae. Although a rigorous cladistic analysis has never been attempted, two hypotheses regarding relationships among these families have been proposed. One early noncladistic hypothesis considered the Sparidae to be intermediate between the more primitive Nemipteridae and the more derived Lethrinidae. A later nonformal phylogenetic treatment provided evidence for a close relationship between Sparidae and Centranthidae and suggested a closer affinity between the Nemipteridae and Lethrinidae. We examine 54 osteological, ligament, and squamation characters in representatives of all 45 genera of these families and 4 outgroup taxa. The results of our cladistic analysis are congruent with a cladistic interpretation of the earlier hypothesis, with strong support for the phyletic sequence Nemipteridae, Lethrinidae, Sparidae plus Centracanthidae, with placement of centracanthids unresolved with respect to sparid genera. Received: May 21, 2001 / Revised: October 26, 2001 / Accepted: November 19, 2001  相似文献   

19.
With the discovery of Alteuthoides kootare gen. et sp. no v. , found living inside an hexactinellid sponge from offshore waters of New Zealand, and the synonymization herein of Paralteutha T. Scott with Eupelte Claus, the number of genera in the harpacticoid copepod family Peltidiidae Sars now stands at eight. In the morphology of the maxillipeds and the armature of the first leg exopods, Alteuthoides is most similar to Alteuthella (A. Scott) and Alteuthellopsis Lang. These shared apomorphies are regarded as convergent ecological specializations to a lifestyle as close associates of other marine invertebrates. Results of a cladistic analysis further assist in the interpretation of relationships within the family. Lang's speculation that Peltidium and Parapeltidium form an independent lineage from the ancestral peltidiid gains further support. Alteutha remains as the basal group to the second lineage in comparison with which all remaining genera are derived in some respect. Alteuthellopsis would appear to be the most advanced genus in the family. Because of recent additions to Neopeltopsis Hicks and Alteuthellopsis , revised diagnoses, together with a revised key to genera, are also presented.  相似文献   

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