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1.
中国蚌螨属支序分类分析(蜱螨亚纲:蚌螨科)   总被引:1,自引:0,他引:1  
选择35个特征对我国蚌螨属15种的支序分析结果表明:蚌螨P-Ⅳ(胫节)端腹部的指状突是将它们聚集成两群的主要特征.今村蚌螨P-Ⅳ端腹部仅具有短矩,与外群最近,认为是我国的蚌螨属水螨中最原始的种类;雌螨前殖吸盘板的形态影响戊蚌螨亚属与多盘蚌螨亚属的种类聚类,由此推测可以将蚌螨P-Ⅳ端腹部的指状突与雌螨前殖吸盘板的形态也作为蚌螨亚属的区分特征.由于殖吸盘结构简单是祖征态之一,因此认为具有5对殖吸盘的邻近蚌螨比6对殖吸盘的厚蚌螨更原始.雌螨具有1对殖吸盘板的寄蚌螨亚属种类与沃蚌螨亚属种类在支序系统树中形成姊妹群,结果支持Vidrine 将沃蚌螨亚属从寄蚌螨亚属中分离的修订.  相似文献   
2.
论山毛榉科植物的系统发育   总被引:8,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   
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4.
The dental and cranial morphologies of all species ofSaguinus, S. oedipus, S. geoffroyi, S. leucopus, S. nigricollis, S. fuscicollis, S. labiatus, S. mystax, S. imperator, S. bicolor, andS. midas are examined. The following hypotheses are developed by cladistic methodology, using only synapomorphic characters to assess the interspecific relationships ofSaguinus.Saguinus are divided into two main groups; one consists ofS. oedipus, S. geoffroyi, andS. leucopus, and the other includesS. inustus, S. nigricollis, S. fuscicollis, S. labiatus, S. mystax, S. imperator, S. bicolor, andS. midas. In the former group,S. oedipus is more closely related toS. geoffroyi than either is toS. leucopus. In the latter group,S. labiatus, S. mystax, andS. imperator are classified into one group, andS. bicolor andS. midas form one monophyletic group.  相似文献   
5.
SCOTLAND, R. W., 1992. Systematics, similarity and Acanthaceae pollen morphology. A brief discussion of the history of Acanthaceae classifications is provided. It is argued that several approaches utilizing pollen morphological data for the classification of the family can be identified. The Lindau pollen types are shown to have an indirect relationship to Lindau's own classification. Pollen morphological similarity is explored within the context of cladistic methodology. It is shown that some of the Lindau pollen types are analogous. It is demonstrated that shared similarities can be of three types: conflicting (homoplasious), plesiomorphic and apomorphic.  相似文献   
6.
中国柽柳属植物的分支分类研究   总被引:2,自引:0,他引:2  
选取生长习性、植物形态、解剖结构、花粉特征以及种子微形态特征等共66个性状,采用简约法对国产柽柳属16种植物及外类群红砂Hololachne songarica进行分支分析,并用靴带检验法(Bootstrap)计算内部分支的支持率。分支图表明,国产柽柳属植物分为4个分支,分别属于Baum(1978)所划分的组Ⅰ及组Ⅱ中不同的系,从一个侧面说明基于经典分类所划分的组是比较自然的,同意Baum的属下分类系统。同时,基于分支分类结果并结合分子证据,对国产柽柳属属间亲缘关系及有争议种的分类学地位进行了探讨,认为甘蒙柽柳是独立于中国柽柳的种,多花柽柳是独立于多枝柽柳的种,盐地柽柳是刚毛柽柳的变种,而叶抱茎呈鞘状的沙生柽柳和莎车柽柳系统学关系很近,是较为原始的一类柽柳。  相似文献   
7.
中国猕猴桃属植物叶表皮毛策形态特征及数量分类分析   总被引:11,自引:0,他引:11  
选取国产猕猴桃35个分类群的代表植株,应用光学显微对其新鲜叶表皮毛的微形态特征,形体大小、细胞结构、分布和密度等多态性状和数量性状进行了观察和测量,该属植物的叶表皮毛微形态特征可归纳为6个类型:1)单细胞毛;2)单列多细胞毛,每形单列毛、泡状单列毛、扭曲毛、直壁单列毛、曲壁单列毛;3)多列渐尖毛和急尖毛,包括多列曲壁渐尖毛和急尖毛,多列直壁渐尖毛和急尖毛;4)多列粗毛,包括柱状毛,多列渐尖粗毛,多  相似文献   
8.
The origin and diversification of RNA secondary structure were traced using cladistic methods. Structural components were coded as polarized and ordered multi-state characters, following a model of character state transformation outlined by considerations in statistical mechanics. Several classes of functional RNA were analyzed, including ribosomal RNA (rRNA). Considerable phylogenetic signal was present in their secondary structure. The intrinsically rooted phylogenies reconstructed from evolved RNA structure depicted those derived from nucleic acid sequence at all taxonomical levels, and grouped organisms in concordance with traditional classification, especially in the archaeal and eukaryal domains. Natural selection appears therefore to operate early in the information flow that originates in sequence and ends in an adapted phenotype. When examining the hierarchical classification of the living world, phylogenetic analysis of secondary structure of the small and large rRNA subunits reconstructed a universal tree of life that branched in three monophyletic groups corresponding to Eucarya, Archaea, and Bacteria, and was rooted in the eukaryotic branch. Ribosomal characters involved in the translational cycle could be easily traced and showed that transfer RNA (tRNA) binding domains in the large rRNA subunit evolved concurrently with the rest of the rRNA molecule. Results suggest it is equally parsimonious to consider that ancestral unicellular eukaryotes or prokaryotes gave rise to all extant life forms and provide a rare insight into the early evolution of nucleic acid and protein biosynthesis. Received: 13 September 2000 / Accepted: 27 August 2001  相似文献   
9.
The relationships between 49 naviculoid diatoms, currently arranged in 14 families and four orders were investigated using cladistic analysis in order to test the types of characters used in diatom systematics and to assess how well the current classification reflects possible phylogenetic relationships in this group. Some of the families and orders comprise taxa with different protoplast characters, or taxa with similar protoplast arrangements are placed in separate families or orders. Therefore as both cell wall and protoplast characters were used, three analyses were undertaken; total data, protoplast data and frustule data. The analyses support the recognition of the Mastogloiales (unequivocally) and the Cymbellales (largely) but indicate that some of the familial groupings are more ambiguous. The members of the Berkeleyaceae, Berkeleya, Parlibellus and Climaconeis, were never grouped together and Achnanthes brevipes never grouped with the other monoraphid diatoms, but usually with members of the Mastogloiales (total and protoplast data). Similarly, Round et al.’s familial groupings within the Cymbellales do not emerge from our analyses. Our results support the hypothesis that monoraphid genera have arisen independently from different naviculoid diatoms, and that Achnanthes sensu stricto should be transferred to the Mastogloiales. Some of the problems associated with incomplete information and inaccurate terminology are discussed briefly.  相似文献   
10.
Phylogenetic systematics of the nymphaeales   总被引:2,自引:0,他引:2  
A cladistic analysis was applied to reveal the phylogenetic relationships among the Nymphaeales. Seventeen out of twenty three characters in gross morphology, anatomy and palynology were analyzed, for their evolutionary polarities. From the results of the present analysis, the phylogenetic status of each genus and their relationships were clarified: 1)Nelumbo is a distinct taxon and is presumed to have originated from an ancestral stock of the Nymphaeales; 2)Ceratophyllum has a close phylogenetic relationship withCabomba; and 3) in the Nymphaeaceaesensu stricto, Nuphar and the remaining genral constitute a monophyletic group. A conclusion obtained from the present analysis was that the following three families should be recognized in the Nymphaeales; Nelumbonaceae Nymphaeaceae, and Ceratophyllaceae. The generaBrasenia andCabomba are traditionally classified in the Nymphaeaceae or in the independent family Cabombaceae. However, they should be included in the family Ceratophyllaceae.  相似文献   
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