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1.
基于ITS、rpl16和trnS-trnR DNA序列讨论锥形果属的系统位置   总被引:1,自引:0,他引:1  
基于核基因ITS和叶绿体基因rpll6、trnS-trnR的DNA序列讨论了锥形果属的系统位置,3个基因片段独立以及联合的分析为锥形果属Gomphogyne的系统进化研究提供了足够的信息.结果表明:(1)锥形果属是一个自然属;(2)雪胆属Hemsleya的短柄雪胆H. delavayi和圆锥果雪胆H. macrocarpa曾经被作为锥形果属的种,分子证据表明它们确实隶属于雪胆属;(3)锥形果属单独构成雪胆属的姊妹群,而并非是与绞股蓝属Gynostemma共同构成.  相似文献   

2.
The genus Gynostemma consists of 16 species and 2 varieties, which fall into two subgenera and two sections, i. e. , Subgen. Trirostellum including two new sections, Sect. Pentagynae and Sect. Trirostellae, and Subgen. Gynostemma. The modern distribution centre of the genus ranges from drainage areas of the Yangtze River to Yunnan, southwest China. Northwards, it is distributed to the south slope of the Qinling Range and the south branch of the Huaihe River, eastwards through central-eastern China to Korea Peninsula and northern Japan; in the south, it extends to Indo-China, Malaysia, Philippines, Indonesia and Papua New Guinea, with the west limit of this genus found in northwestern India.The distribution pattern of the genus indicates a nature of Tropical Asia Type. Based on the above mentioned distribution pattern, the centre of diversification and the ecological adaptation of both primitive and advanced groups, also by means of palaeogeological, palaeogeographical and palaeoclimatical evidence and the origin of its out group, the genus Gynostemma, together with its closely allied genera Hemsleya, Gomphogyne, etc. is considered to have originated on the Kham-Dian Oldland during the Early Tertiary.  相似文献   

3.
绞股蓝属植物的分类系统和分布   总被引:34,自引:0,他引:34  
绞股蓝属全世界有16种2变种,隶属于2亚属2组,即喙果藤亚属(包括五柱绞股蓝组和喙果藤组)及绞股蓝亚属。其现代分布中心或多样化中心为我国长江流域至西南的云南,由此向北达秦岭南坡和淮河流域以南,向东北经华中、华东至朝鲜半岛和日本北部,向南经中南半岛、马来西亚达菲律宾、印度尼西亚诸岛和巴布亚新几内亚,向西达印度西北部,为热带亚洲分布类型。根据该属的原始类群和进化类型的现代分布和多样化中心及它们的生态适应性,与古地质、古地理和古气候的变迁以及外类群起源地等推测,绞股蓝属植物可能与其近缘属——雪胆属和锥形果属共同起源于康滇古陆,起源时间可能为早第三纪。  相似文献   

4.
Wu J  Wu Y  Yang BB 《Life sciences》2002,71(18):2161-2170
Hemsleya amabilis extract is derived from the medicinal herb Hemsleya amabilis, which has long been used to treat cancer and many other conditions. The underlying mechanism is not clear. To investigate Hemsleya amabili's anticancer activity, we have treated different types of cancer cells including human astrocytoma U87 cells, breast cancer cells MDA-MB-231and Jurkat cells with Hemsleya amabilis extract. This agent significantly inhibited tumor cell growth and colony formation at various concentrations. When astrocytoma cells were seeded in the presence of Hemsleya amabilis extract at very low concentrations, cell spreading was greatly inhibited. Hemsleya amabilis extract also promoted tumor cell death in all the tested cell lines, but with varied sensitivities. Apoptotic assays with Annexin V staining demonstrated that Hemsleya amabilis extract induced astrocytoma cell apoptosis at different concentrations.  相似文献   

5.
the present paper is a meterial of the genus Hemsleya Cogn. for flora of China-Cucurbitaceae. The genus Hemsleya was established by C. A. Cogniaux in 1889. By 1982 about 7 species had been discovered in China, and most of them are mainly distributed in S. W. China, particularly in Yunnan and Sichuan. Their tubers have been used as a folk medicine for a long time. However, we began to search for them, and meanwhile collect and cultivate them, only about ten years ago. After a general survey and taxonomical study, 20 species of Hemsleya are recorded from Yunnan in the paper. Among them 18 species and 3 varieties are new. All the types are kept in Herb. KUN. According to the characters, of corolla and fruit also the seed condition, widely or narrowly winged, proposed are four sections, namely: Sect. I. Craciliflorae; Sect. II. Amabiles; Sect. III. Carnosiflorae and Sect. IV. Hemsleya, among which 3 are new.  相似文献   

6.
巨花雪胆中的两个新化合物   总被引:4,自引:0,他引:4  
从四川石棉县采集的巨花雪胆(Hemsleya gigantha)的根茎中分到2个新化合物,命名为雪胆素G和巨花雪胆皂苷B,通过化学方法和波谱方法鉴定了它们的结构。另外13个已知化合物分别为葫芦素类和雪胆皂苷类化合物,其中β—香树脂醇(3)为首次从该属植物中得到。  相似文献   

7.
8.
Ecnomidae are a family of seven previously accepted extant genera having a typical Gondwanan distribution, except one genus ( Ecnomus ) being widely distributed also in the Oriental and Palearctic regions. We analysed a molecular data set of 3379 characters representing the sum of four different protein-coding genes (COI, CAD, EF-1a and POL-II). Six equally most parsimonious trees were generated from the combined data set, distributed into two distinct islands. In all maximum parsimony (MP) trees the Ecnomidae is monophyletic when the genus Zelandoptila (Psychomyiidae) is included. The sister group to Ecnomidae including Zelandoptila is Pseudoneureclipsis , previously classified in the other families. This sister-group relationship contradicts earlier findings that the Polycentropodidae are the sister group to Ecnomidae. A Bayesian analysis resulted in a monophyletic Ecnomidae when accepting inclusion of Pseudoneureclipsis , which contradicts the results from the MP analysis by leaving Zelandoptila as the sister group to Ecnomidae including Pseudoneureclipsis . In the majority rule tree from this analysis Polycentropodidae form the sister group to Ecnomidae. We were not able to obtain a monophyletic Ecnomus due to the inclusion of Psychomyillodes . We conclude that the genus Zelandoptila or Pseudoneureclipsis probably belongs to the Ecnomidae, and that Psychomyiellodes and Ecnomus are synonyms. Three additional, as yet undescribed monotypic genera from Australia and New Caledonia remain to be erected in Ecnomidae.
© The Willi Hennig Society 2009.  相似文献   

9.
We present the first phylogenetic study on the widespread Middle American microhylid frog genus Hypopachus. Partial sequences of mitochondrial (12S and 16S ribosomal RNA) and nuclear (rhodopsin) genes (1275 bp total) were analyzed from 43 samples of Hypopachus, three currently recognized species of Gastrophryne, and seven arthroleptid, brevicipitid and microhylid outgroup taxa. Maximum parsimony (PAUP), maximum likelihood (RAxML) and Bayesian inference (MrBayes) optimality criteria were used for phylogenetic analyses, and BEAST was used to estimate divergence dates of major clades. Population-level analyses were conducted with the programs NETWORK and Arlequin. Results confirm the placement of Hypopachus and Gastrophryne as sister taxa, but the latter genus was strongly supported as paraphyletic. The African phrynomerine genus Phrynomantis was recovered as the sister taxon to a monophyletic Chiasmocleis, rendering our well-supported clade of gastrophrynines paraphyletic. Hypopachus barberi was supported as a disjunctly distributed highland species, and we recovered a basal split in lowland populations of Hypopachus variolosus from the Pacific versant of Mexico and elsewhere in the Mesoamerican lowlands. Dating analyses from BEAST estimate speciation within the genus Hypopachus occurred in the late Miocene/early Pliocene for most clades. Previous studies have not found bioacoustic or morphological differences among these lowland clades, and our molecular data support the continued recognition of two species in the genus Hypopachus.  相似文献   

10.
Bulbuls (Aves: Pycnonotidae) are a fairly speciose (ca. 130 sp.) bird family restricted to the Old World. Family limits and taxonomy have been revised substantially over the past decade, but a comprehensive molecular phylogeny for the family has not been undertaken. Using nuclear and mitochondrial DNA sequences, we reconstructed a well-supported phylogenetic hypothesis for the bulbuls. Three basal lineages were identified: a large African clade, a large Asian clade that also included African Pycnonotus species, and the monotypic African genus Calyptocichla. The African clade was sister to the other two lineages, but this placement did not have high branch support. The genus Pycnonotus was not monophyletic because three species (eutilotus, melanoleucos, and atriceps) were highly diverged from the other species and sister to all other Asian taxa. Additional taxon sampling is needed to further resolve relationships and taxonomy within the large and variable Hypsipetes complex.  相似文献   

11.
The phylogenetic position of the genera Rossithidium and Psammothidium was studied using the plastid gene rbcL. The genus Rossithidium is not an independent taxon and should be transferred to Psammothidium. Taxa from Psammothidium genus formed a sister, but independent clade to taxa with Achnanthidium. Our data has shown that the order Achnathales was not the natural taxon and should be reduced, but the three families included in it were natural. Genera like Psammothidium (including Rossithidium) and Lemnicola should be included into the family Achnanthidiaceae. Therefore, raphe does not play an important role in diatom taxonomy and its loss occurred many times during the evolution of diatoms.  相似文献   

12.
Like many lichen-forming fungi, species of the genus Rhizoplaca have wide geographical distributions, but studies of their genetic variability are limited. The information about the ITS rDNA sequences of three species of Rhizoplaca from Anatolia was generated and aligned with other species from other countries and also with the data belonging to Lecanora species. The examined species were collected from the volcanic rocks of Mount Erciyes which is located in the middle of Anatolia (Turkey). The sequence data aligned with eight other samples of Rhizoplaca and six different species of Lecanora were obtained from GenBank. The results support the concept maintained by Arup and Grube (2000) that Rhizoplaca may not be a genus separate from Lecanora. According to the phylogenetic tree, Rhizoplaca melanopthalma from Turkey with two different samples of R. melanopthalma from Arizona (AF159929, AF159934) and a sample from Austria formed a group under the same branch. R. peltata and R. chrysoleuca samples from Anatolia located in two other branches of the tree formed sister groups with the samples of the same species from different countries. Although R. peltata remained on the same branch with other samples of the same species from other countries it was placed in a different branch within the group. When the three species from Anatolia were considered alone, it was noticed that Rhizoplaca melanopthalma and Rhizoplaca peltata are phylogenetically closer to each other than Rhizoplaca chrysoleuca; the morphological characteristics also support this result.  相似文献   

13.
A review of available Caribbean Island red-lists species (CR and EN categories based on the IUCN guidelines from 2001, and E category established according to the IUCN guidelines from 1980) is presented. A database of over 1,300 endemic species that are either Critically Endangered or Endangered sensu IUCN was created. There are molecular systematic studies available for 112 of them. Six of these species (in six genera) are the only members of early divergent lineages that are sister to groups composed of a large number of clades. Seven of the species (in seven genera) belong to clades that have a small number of taxa but are sister to species/genus-rich clades. Ten of the species (in six genera) are sister to taxa restricted to South America or nested in clades endemic to this region. Fifty-seven of the species (in 35 genera) are sister to Caribbean Island endemic species. Erigeron belliastroides, an Endangered (EN) Cuban endemic, is sister to the Galapagos genus Darwiniothamnus. The phylogenetic placement of four of the threatened species resulted in changes in their taxonomic placement; they belong to polyphyletic or paraphyletic genera.  相似文献   

14.
Abstract—Cyttaria Berkeley (Cyttariaceae, Cyttariales, Class Discomycetes), is a genus of eleven species, seven from South America and four from Australasia (Australia, Tasmania, and New Zealand). Cyttaria is a monophyletic genus defined by the following synapomorphies: fleshy to gelatinous stromata with endostromatic apothecia; and complete lack of fungal chitin in the cell walls, having instead β-1–3-glucan. All Cyttaria are exclusive parasites of Nothofagus species. A cladistic analysis of the genus was performed using 18 characters from macromorphology, micro-morphology, and phenology. Polarity of characters is based on the outgroup comparison method (using the Class Discomycetes as a whole) and on the ontogenetic criterion. A hypothetical outgroup was constructed using all plesiomorphic states. Two equally parsimonious cladograms were produced, each with 40 steps and a consistency index of 0.70. These differed in the position of the South American species C. hookeri and C. johowii. In one cladogram, C. hookeri is the sister group to the rest of the genus, and in the other, both species form a monophyletic group (ascospores ovoid) that is the sister group of the rest of the genus. Our analysis of the two characters causing this difference (position of apothecia on stroma, and shape of ascospores) supports the latter hypothesis. In both cladograms, all of the Australasian species form a monophyletic group (thick ectostroma), and, within that, two subgroups are defined: C. gunnii-C. pallida (papillae present), and C. nigra-C. septentrionalis (ectostroma with black incrustations). The Australasian species form a monophyletic group (spermatangia absent) with C. berteroi , and this last group forms a monophyletic group (conidia absent) with C. espinosae. Cytlaria darwimi and C. exigua form another monophyletic group (very thick ectostroma). Excluding C. hookeri and C. johowii, C. hariotii is the sister group to the remaining eight species.  相似文献   

15.
为了探讨中国黄粉蝶亚科属间的系统发育关系,我们对其中6属9种的细胞色素氧化酶Ⅱ(COⅡ)的部分序列和延伸因子基因(EF-1α)部分序列进行了分析。分别采用最大简约法(maximum parsimony, MP)、最大似然法(maximum likelihood, ML)和贝叶斯推论法(bayesian inference, BI)构建黄粉蝶亚科分子系统树。结果表明:在测得的COⅡ基因的648 bp序列和EF-1α基因的504 bp序列中,有261个变异位点,151个简约信息位点,黄粉蝶亚科内各属COⅡ基因A+T含量(77.3%)均明显偏高。系统发育分析显示黄粉蝶属为亚科中较为原始的类群,分化较早,豆粉蝶属和迁粉蝶属亲缘关系较近,但钩粉蝶属与豆粉蝶属、迁粉蝶属之间的亲缘关系还不能确定。本研究结果和传统的基于形态学的黄粉蝶亚科的分类体系有所不同,最显著的分歧是本研究支持内群中分化最早的属应为黄粉蝶属,而不是豆粉蝶属和迁粉蝶属。  相似文献   

16.
The diversity of lacertid lizards in Africa is highest in the southern African subcontinent, where over two-thirds of the species are endemic. With eleven currently recognized species, Pedioplanis is the most diverse among the southern African genera. In this study we use 2200 nucleotide positions derived from two mitochondrial markers (ND2 and 16S rRNA) and one nuclear gene (RAG-1) to (i) assess the phylogeny of Pedioplanis and (ii) estimate divergence time among lineages using the relaxed molecular clock method. Individual analyses of each gene separately supported different nodes in the phylogeny and the combined analysis yielded more well supported relationships. We present the first, well-resolved gene tree for the genus Pedioplanis and this is largely congruent with a phylogeny derived from morphology. Contrary to previous suggestions Heliobolus/Nucras are sister to Pedioplanis. The genus Pedioplanis is monophyletic, with P. burchelli/P. laticeps forming a clade that is sister to all the remaining congeners. Two distinct geographic lineages can be identified within the widespread P. namaquensis; one occurs in Namibia, while the other occurs in South Africa. The P. undata species complex is monophyletic, but one of its constituent species, P. inornata, is paraphyletic. Relationships among the subspecies of P. lineoocellata are much more complex than previously documented. An isolated population previously assigned to P. l. pulchella is paraphyletic and sister to the three named subspecies. The phylogeny identifies two biogeographical clades that probably diverged during the mid-Miocene, after the development of the Benguella Current. This probably led to habitat changes associated with climate and, in conjunction with physical barriers (Great Escarpment), contributed towards speciation within the genus Pedioplanis.  相似文献   

17.
Molecular phylogenies and estimates of divergence times within the sister genera Macaranga and Mallotus were estimated using Bayesian relaxed clock analyses of two generic data sets, one per genus. Both data sets were based on different molecular markers and largely different samples. Per genus three calibration points were utilised. The basal calibration point (crown node of all taxa used) was taken from literature and used for both taxa. The other three calibrations were based on fossils of which two were used per genus. We compared patterns of dispersal and diversification in Macaranga and Mallotus using ancestral area reconstruction in RASP (S-DIVA option) and contrasted our results with biogeographical and geological records to assess accuracy of inferred age estimates. A check of the fossil calibration point showed that the Japanese fossil, used for dating the divergence of Mallotus, probably had to be attached to a lower node, the stem node of all pioneer species, but even then the divergence time was still younger than the estimated age of the fossil. The African (only used in the Macaranga data set) and New Zealand fossils (used for both genera) seemed reliably placed. Our results are in line with existing geological data and the presence of stepping stones that provided dispersal pathways from Borneo to New Guinea-Australia, from Borneo to mainland Asia and additionally at least once to Africa and Madagascar via land and back to India via Indian Ocean island chains. The two genera show congruence in dispersal patterns, which corroborate divergence time estimates, although the overall mode and tempo of dispersal and diversification differ significantly as shown by distribution patterns of extant species.  相似文献   

18.
基于ITS序列探讨杜鹃属的亚属和组间系统关系   总被引:10,自引:0,他引:10  
首次报道了 15种杜鹃属 (Rhododendron)植物、1种杜香属 (Ledum)植物和Cassiopefastigiata的内转录间隔区(ITS) (包括 5 .8S)序列。加上从GenBank下载的 13种杜鹃属植物和Bajiariaracemosa的ITS序列 ,以C .fastigiata和B .racemosa为外类群 ,用最大简约法对杜鹃属的亚属和组间的系统关系进行了分析。结果表明 :1)杜鹃属是一个单系类群 ,叶状苞亚属为杜鹃属的基部类群 ;2 )杜香属确应归并到杜鹃属中 ,且与有鳞杜鹃亚属有较近的亲缘关系 ;3)有鳞杜鹃亚属和杜香构成一个单系分支 ,该分支是其余无鳞杜鹃花的姐妹群 ;4 )由无鳞杜鹃花组成的一个分支的内部支持率较低 ,其中常绿杜鹃亚属和映山红亚属均为内部支持率很高的单系类群 ,而羊踯躅亚属和马银花亚属均为多系类群 ;5 )在马银花亚属中 ,长蕊杜鹃组和马银花组均分别得到强烈支持 ,马银花组与异蕊杜鹃亚属可能构成姐妹群关系 ,异蕊杜鹃亚属和马银花组组成的一个分支可能与映山红亚属构成姐妹群关系。  相似文献   

19.
A phylogenetic analysis of the family Lemuridae was accomplished using multiple gene partitions and morphological characters. The results of the study suggest that several nodes in the lemurid phylogeny can be robustly resolved; however, the relationships of the species within the genus Eulemur are problematically nonrobust. The genus Varecia is strongly supported as the basal genus in the family. Hapalemur and Lemur catta are strongly supported as sister taxa and together are the sister group to the genus Eulemur. E. mongoz is the most basal species in the genus Eulemur. E. fulvus subspecies form a monophyletic group with three distinct lineages. E. coronatus is strongly supported as the sister taxon to E. macaco. The relationships of E. rubriventer, E. fulvus, and the E. macaco-E. coronatus pair are unresolved. Our combined molecular and morphological analysis demonstrates the lack of influence that morphology has on the simultaneous analysis tree when these two kinds of data are given equal weight. The effects of several extreme weighting schemes (removal of transitions and of third positions in protein-coding regions) and maximum-likelihood analysis were also explored. We suggest that these other forms of inference add little to resolving the problematic relationships of the species in the genus Eulemur.  相似文献   

20.
The cestode family Taeniidae consists of 2 genera, Taenia and Echinococcus, which both have been the focus of intensive taxonomic and epidemiological studies because of their zoonotic importance. However, a comprehensive molecular phylogeny of this family has yet to be reconstructed. In this study, 54 isolates representing 9 Taenia species were characterized using DNA sequences in the mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes. Phylogenetic relationships within the family Taeniidae were inferred by combining cox1 and nad1 sequence data of the present and previous studies. In the phylogenetic analysis, the genus Echinococcus was shown to be monophyletic, but Taenia proved to be paraphyletic due to the position of T. mustelae as a probable sister taxon of Echinococcus. This indicates that T. mustelae should form a genus of its own. Taenia ovis krabbei was placed distant from T. ovis ovis, as a sister taxon of T. multiceps, supporting its recognition as a distinct species, T. krabbei. High intraspecific sequence variation within both T. polyacantha and T. taeniaeformis suggests the existence of cryptic sister species.  相似文献   

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