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1.
The phylogenetic relationships of elasmobranchs, especially sharks, are unclear. All previously made research and hypotheses indicate that there are still unsolved relationships within and between the class Chondrichthyes. To find out the relationship and sister group of this genus, the ribosomal ITS1-2 regions sequence has been chosen to differentiate the genus Carcharhinus from the blue shark (genus Prionace) and from some other genus species as an outgroup. The results show that the blue shark is a member of the genus Carcharhinus, suggesting that maybe the blue shark belongs also to the genus Carcharhinus instead of Prionace, or that there is a misclassification, Prionace being not a separate genus.  相似文献   

2.
The genus Glossodoris Ehrenberg is reviewed and 28 species are placed in the genus. Seventeen species are fully described and of these, seven are named as new species. Four others are considered new to science, but insufficient material is available to name them. Published information on a further 11 species is included as is a discussion on phylogenetic trends within the genus.  相似文献   

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Zhuang WY  Luo J  Zhao P 《Mycologia》2011,103(2):400-406
Studies on the genus Acervus from China are reviewed briefly. Six of the seven known species of the genus are currently recorded in this country. Acervus beijingense and A. changchunense are described as new based on morphological features and molecular data, and A. flavidus with minor emendation is added to the Chinese fungus flora. Phylogenetic relationships among four of the seven species of the genus are investigated based on the 28S rDNA sequence analysis. Species of the genus formed a single clade with high bootstrap support. The sequences of A. epispartius forma epispartius and that of A. flavidus obtained from materials in different geographical regions together formed a group with 100% bootstrap support. Ascospore size and shape are important criteria in the taxonomy of the genus and are phylogenetically informative. A dichotomous key to all described species of the genus is provided.  相似文献   

5.
ABSTRACT. The composition and relationships of the Banchus genus-group are discussed. A key to the genera is provided and for each genus a diagnosis and notes are given. A new genus and species are described. The genus Philogalleria Cameron is revised: six species (five of them new) are recognized, described and keyed. Rhynchobanchus is newly recorded from Britain and a key is given to its European species.  相似文献   

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中国杭子梢属植物的研究   总被引:2,自引:0,他引:2  
傅沛云 《植物研究》1987,7(4):11-55
本文叙述了杭子梢属(gen.Campylotropis)植物的研究历史,说明在中国一共记录过59种杭子梢属植物,经过著者的研究整理,确定并提出了14种新的异名名称,经过详细考订,本属植物在中国已确知为29种、6变种、6变型。其中包括经发现和研究整理的新种4、新变种3、新变型3、新组合变种2、新组合变型3。此外尚有2个存疑种有待今后采集调查解决。本文历述了关于本属是否应该并入胡枝子属(gen.Lespedeza)这一问题所存在的长期争议之后,详细论述了本属与胡枝子属在特征上的异同诸点、进行了比较和分析,据此,明确地肯定本属与胡枝子属亲缘关系极为相近,但特征的分化已经必须确认本属应是与胡枝子属有明确区别的独立的属。此外,从特征分析中也可得出本属应是由胡枝子属大胡枝子组(sect.Macrolespedeza)演化发展而来的。本文在讨论了属内主要特征的演化趋势与种群关系之后,论述了本属在世界主要分布地区的种数和分布概况,同时将此与胡枝子属大胡枝子组的分布概况作了比较和分析,明确地认定我国机子梢属植物的大部分种类是本国西南地区发生的(中国有20个特有种),我国的西南地区是本属植物的分布中心,也是本属植物从较原始特征开始分化的一个特征分化多样化中心,并且此地区正是胡枝子属大胡枝子组与本属多数种类包括较原始种类分布相交叉的地区,因而我国的西南地区有可能即是本属植物的起源中心,并且这一起源应是与胡枝子属大胡枝子组植物分布到中国西南地区以后的分化发展想联系的。  相似文献   

8.
Abstract. The ant genus lshakidris from Sarawak is described as new. Its relationships with the Brasilian monotypic genus Phalacromyrmex Kempf and the Malagasy monotypic genus Pilotrochus Brown are discussed, and the Phalacromyrmex genus-group is established to hold the three genera. The resemblances of lshakidris to the smithistrumiform dacetine genus Glamymmyrmex Wheeler and the agroecomyrmecine genus Tatuidris Brown & Kempf are discussed and the similarities are analysed as the results of convergence in the characters concerned.  相似文献   

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The genus Dichocarpum was established by W. T. Wang and Hsiao in 1964, who divided the genus into 2 sections: Sect. Dichocarpum including 10 species distributed on the mainland of E. Asia, and Sect. Hutchinsonia including 9 species native to Japan. M. Tamura and L. A. Lauener made a revision of the genus in 1968, who divided the genus into 4 sections, three for the species of the mainland of E. Asia, including 3 series and 10 species, and the other for the species of Japan, including 2 subsections, 3 series and 9 species. In the present paper, the genus is divided into 2 sections and 6 series, including 15 species and 3 varieties, and a putative phylogeny of the genus is proposed. The genus may be close to the genus Asteropyrum, and these two genera are rather specialized in Thalictroides (Ranunculaceae), because they have three very similar characters: the petal with a long claw, the stephanocolpate pollen and the chromosome morphology. The genus has 2n=24, 35(36?), which indicates that its basic number is X=6, and the species on the mainland of E. Asia (Sect. Dichocarpum) may well be paleotetraploids, whereas those in Japan (sect. Hutchinsonia) are paleohexaploids. Most of the advanced species are distributed in Japan and the most primitive ones in China and the Himalayas, the distribution pattern seggests that the Japanese members of this genus might have immigrated from China in the Tertiary, and differentiated and evolved there. The putative phylogeny of the genus is shown in Fig. 2 (at series level)  相似文献   

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The genus Cephalotaxus contains a small number of species. It is adequately appreciated as a newly discovered cancerresistant medicament for the alkaloids obtained from its branches leaves and barks are of curative effect. This paper deals with the classificatory revision based on the morphological features, with the reference to the anatomical characters of leaves, types of alkaloids and pollen morphology observed. Two new combinations are proposed, and 4 species and varieties are reduced in the paper. The genus Cephalotaxus is thus suggested to consist of 2 sections and 9 species. The trees occur in East Asia and the north of Indo-China, with 88% found in China where is the distribution centre and refuge of the genus. The genus in discussion is of unique morphological features which are distinctly different from these of Amentotaxus, Cephalotaxaceae, containing a single genus of Cephalotaxus, is closely related to Taxaceae, and therefore the Cephalotaxaceae is best placed in the Taxinieae of Coniferales.  相似文献   

13.
A phylogenetic analysis based on 16S rRNA gene sequences reveals that Alysiella filiformis belongs to the family Neisseriaceae. The genus Simonsiella is phylogenetically separated by the genera Kingella and Neisseria. The species Simonsiella crassa and A. filiformis show a close phylogenetic relationship, with the 16S rDNA sequence similarity and the DNA-DNA hybridization representing 98.7% and 35%, respectively. Therefore, S. crassa should be transferred from the genus Simonsiella to the genus Alysiella as Alysiella crassa comb. nov. Simonsiella steedae and Simonsiella sp. of cat origin show strong genetic affinities and are distantly related with the type species of Simonsiella, S. mulleri. Thus, a new genus, Conchiformibium is proposed; Conchiformibium steedae comb. nov. and Conchiformibium kuhniae sp. nov. are accommodated in this new genus. On the basis of the phylogenetic, phenotypic and chemotaxonomic distinction from the genus Neisseria, N. denitrificans should be reclassified, for which a new genus and new combination Bergeriella denitrificans are proposed.  相似文献   

14.
中国筇竹属植物志资料   总被引:4,自引:0,他引:4  
筇竹属是近年来新建立的一个属。本属原发表时仅有3种,标本採自四川、云南、贵州及湖北西部。以后又陆续发表了4种。作者在编写中国植物志筇竹属的过程中,对本属又做了初步整理,其中包括一新种及一新变型也在此一并发表。本文引证的标本均藏于本院标本室(代号SWFC)。  相似文献   

15.
Abstract. The South African genus Pameridea and its two species are redescribed. The tribe Pamerideini, founded for this genus only, is removed from synonymy with Mirini (subfamily Mirinae) and transferred to Dicyphini (subfamily Bryocorinae), falling as a synonym of the subtribe Dicyphina. The bugs live only on intensely viscid small shrubs of the genus Roridula. This plant genus is the only member of its family but the bug genus is closely related to two widespread tropical dicyphine genera.  相似文献   

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中国木兰科11属40种植物的核形态研究   总被引:12,自引:0,他引:12  
为了探讨木兰科属间系统学关系和一些种的分类学地位,对中国木兰科11属40种进行了核形态研究。所研究的20种木莲属植物都为二倍体,表明木莲属植物主要是在二倍体水平上进化的,不同的种类具有各自的遗传组成,细微的染色体结构变异可能导致种间形态发生了明显的变化。木兰属的染色体数目具多样性,表明属内存在着不同倍性水平上的进化,说明木兰属分布广泛、形态复杂多样有其细胞学基础。细胞学证据支持木莲属应为独立的属,不宜于归并到木兰属。已观察的含笑属都为二倍体,而木兰属玉兰亚属的大多数种类为多倍体。我们认为维持现有的含笑属的分类地位和范围是恰当的,不支持将含笑属和玉兰亚属合并为一属。拟单性木兰属都是多倍体。木兰科植物形态特征重叠,性状呈网状进化,细胞学证据在探讨一些大属属下种的分类地位时具有一定价值,但论及整个科的分类系统和属间亲缘关系时,作用比较微弱。本文在细胞学基础上,结合形态和地理分布,重点对木莲属一些种类的分类地位进行了讨论。  相似文献   

18.
A detailed morphological and anatomical study of the tropical African genus Virectaria is presented. The observations are used to characterize the genus, to propose a key to all eight species, and to unravel the relationships between the species using cladistics. A taxonomic survey of the genus is also given. Verdcourt's infraspecific taxa based on calyx morphology in V major are adopted, but it was found that morphological distinction is correlated with ecological, habit and distributional differences. Hence, it is better to recognize Verdcourt's varieties spathulata and major as subspecies of V. major. The problematic systematic position of the genus is discussed in detail. New evidence is given for the exclusion of the genus from the Hedyotideae and Ophiorrhizeae (subfamily Rubioideae). The recently proposed position in the Sabiceeae (subfamily Ixoroideae) is not convincing either, since none of the genera included in the Sabiceeae matches Virectaria with respect to pollen, fruit, flower and growth habit. Exclusion from the Rubioideae and a position near the Sabiceeae is supported by lack of raphides, seed anatomy, placentation, stipule morphology and molecular evidence. Molecular data from a larger number of taxa are needed to confirm the position of the genus.  相似文献   

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Knížek M 《ZooKeys》2010,(56):191-206
Fivenew species of the genus Triotemnus from Morocco and Yemen are described. Triotemnus is a new genus of Scolytinae for the Yemen region. External morphology of the new species and all morphologically related species of the genus were studied. While the new species from Morocco are morphologically similar to the known species from the corresponding region, all three newly described species from Yemen, mainly two of them living in Socotra, are morphologically very different from all other known species of the genus. Geographical distribution and the probability of endemicity are discussed.  相似文献   

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