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1.
The flavonoid pattern of the monotypic Turkish genus Leucocyclus consists of C-glycosylflavones (isovitexin; isoorientin and derivatives; several di-C-glycosylapigenins; schaftoside, isoschaftoside and vicenin-3; lucenin-2), of flavonol 3-O-glycosides (quercetin and kaempferol 3-O-rhamnoglucoside) and trace amounts of luteolin 7-O-rhamnoglucoside. The systematic significance of the flavonoid diversification within Leucocyclus as well as possible relationships to other genera of the Anthemideae are discussed.  相似文献   

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A survey of over 250 representative taxa in the Umbelliferae has shown that sulphates only accumulate in three genera, Ammi, Daucus and Oenanthe. The presence of quercetin, rhamnocitrin, rhamnetin and isorhamnetin 3-sulphate in Ammi visnaga serves to distinguish it from the related A. majus which lacks sulphates. In Daucus carota leaf, the 7-and 4′-sulphates of luteolin both occur; the two characters are polymorphic and appear to be present more frequently in North temperate than in South temperate populations. Oenanthe is the only genus where sulphates are found abundantly; they occur in 7 of 9 species surveyed. In addition to the known isorhamnetin 3sulphate of O. stolonifera, quercetin 3-sulphate and luteolin 7-sulphate were identified for the first time in the genus. The synthesis of various kaempferol and quercetin sulphates is described.  相似文献   

4.
The flavonoid pigments of Potamogeton praelongus Wulfen, P. perfoliatus L., and P. richardsonii (A. Benn.) Rydberg were isolated and identified. Five flavone glycosides based on three aglycone types and one C-glycosylflavone were identified. Potamogeton perfoliatus and P. richardsonii are most similar in flavonoid composition. The greatest number of compounds are found in P. praelongus with the other two species having a subset of its profile. The flavonoid data suggest that P. richardsonii arose by means other than hybridization between P. perfoliatus and P. praelongus.  相似文献   

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A molecular phylogeny of the genus Artibeus using 19 of the 20 recognized species, many with samples from a broad geographic range, is presented. The analysis shows a clear distinction between the two subgenera (or genera), the 'large'Artibeus and the 'small'Dermanura, in both mitochondrial and nuclear genes. The placement and status of A. concolor remains inconclusive and is presented as the third subgenus Koopmania. The phylogenies and divergence time estimates show a marked influence of the Andes in the formation of the subgenera and the main lineages inside each subgenus. Nuclear genes showed a highly incomplete lineage sorting among species inside subgenera Artibeus and Dermanura. Indeed, shared alleles were also found between Artibeus and Koopmania, which are presumed to have split apart during the Miocene, showing that great care should be taken in using these markers. Cytochrome-b gene divergences and monophyly analyses suggest that A. lituratus and A. intermedius are indeed conspecifics. These analyses also suggested the existence of at least four 'new' species revealing a significant cryptic diversity inside the genus.  相似文献   

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Phylogenetic analyses of cytochrome c oxidasesubunit I (627bp) and mitochondrial controlregion (338bp aligned) sequences for all knownspecies of Allodontichthys wereperformed. Allodontichthys was recoveredas monophyletic, and A. hubbsi wassupported as the most primitive member of thegenus in all analyses. Combined-data analysessuggest that A. polylepis is sister to aclade comprising A. tamazulae and A. zonistius; however, a strict consensus of COIand control region cladograms results in acollapse of this node. The two species thatare broadly sympatric, A. hubbsi and A. tamazulae, are not sister taxa.Allodontichthys was found the sistergroup of a clade including Ilyodon andXenotaenia. These three genera are theonly goodeids to occupy high-gradient riversystems. Ilyodon and Allodontichthys share similar distributions;however, Allodontichthys exhibits greaterthan an order of magnitude more geneticvariation in COI than Ilyodon incomparisons of individuals from the samelocalities in the Ameca and Armeria drainagesystems. This is interpreted to mean Allodontichthys arrived in some westerndrainages significantly before Ilyodon.The Rio Coahuayana appears to be the center oforigin of the genus Allodontichthys. This river basin contains the most primitivemember of the genus, and appears to haveconnected with the Mesa Central, the center of endemism of the Goodeidae. A calibrated rateof molecular change in COI reveals Allodontichthys began diverging approximately6.2 million years ago (mya). Remainingspeciation in the group appears to haveoccurred about 2.7 to 3.3 mya. The hypothesisthat a hard polytomy comprising A. zonistius, A. polylepis, and A. tamazulae could be explained by speciation ofA. polylepis and A. tamazulae fromdifferent A. zonistius ancestors ispresented. Stream capture is evident but notfrequent in the history of Allodontichthys, and speciation does notclearly correlate with documented geologicactivity of the Mexican Transvolcanic Belt.  相似文献   

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Echinococcosis is a serious helminthic zoonosis in humans, livestock and wildlife. The pathogenic organisms are members of the genus Echinococcus (Cestoda: Taeniidae). Life cycles of Echinococcus spp. are consistently dependent on predator–prey association between two obligate mammalian hosts. Carnivores (canids and felids) serve as definitive hosts for adult tapeworms and their herbivore prey (ungulates, rodents and lagomorphs) as intermediate hosts for metacestode larvae. Humans are involved as an accidental host for metacestode infections. The metacestodes develop in various internal organs, particularly in liver and lungs. Each metacestode of Echinococcus spp. has an organotropism and a characteristic form known as an unilocular (cystic), alveolar or polycystic hydatid. Recent molecular phylogenetic studies have demonstrated that the type species, Echinococcus granulosus, causing cystic echinococcosis is a cryptic species complex. Therefore, the orthodox taxonomy of Echinococcus established from morphological criteria has been revised from the standpoint of phylogenetic systematics. Nine valid species including newly resurrected taxa are recognised as a result of the revision. This review summarises the recent advances in the phylogenetic systematics of Echinococcus, together with the historical backgrounds and molecular epidemiological aspects of each species. A new phylogenetic tree inferred from the mitochondrial genomes of all valid Echinococcus spp. is also presented. The taxonomic nomenclature for Echinococcus oligarthrus is shown to be incorrect and this name should be replaced with Echinococcus oligarthra.  相似文献   

9.
Data for the flavonoids of 19 species in 10 sections of Ludwigia are presented. Eight flavonoids, comprising four glycoflavones, of which vitexin and isovitexin are reported for the first time in Ludwigia, and four flavonol glycosides, based on quercetin, are present in these species. Each section treated here has either glycoflavones or flavonols; presence of only onte class is considered to be advanced in the genus as a whole, compared with the presence of both glycoflavones and flavonols in the more generalized sects Myrtocarpus Cinerascentes, and Pterocaulon, which were examined earlier. Only glycoflavones are present in sects Macrocarpon (four species), Seminuda (five species), the ditypic African sect. Africana, the monotypic African sects Brenania, Cryptosperma, and Prieurea, the monotypic east Asian sect. Nipponia, and the monotypic pantropical section Fissendocarpa. Only flavonols are present in the monotypic Old Wodd section Caryophylloidea and sect. Oligospermum, which comprises nine species widespread in the OId and New Worlds.  相似文献   

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A review of the genus Semele (Ruscaceae) systematics in Madeira   总被引:2,自引:0,他引:2  
The present study attempts to review the systematics of Semele (Ruscaceae) in Madeira, based on phenotypic diversity. The variation in some vegetative (climbing shoot, second-order branches or 'phylloclades') and sexual (inflorescence and flowers) characters was analysed in 115 plant specimens from 30 field populations, herbaria of the Costa collection and Madeira Botanical Garden (MADJ) and certain gardens. Thirty-one quantitative and qualitative characters have been utilized in the analysis. Kaiser–Meyer–Olkin (KMO) analysis indicates adequate sampling. Principal component analysis (PCA) reveals that the spatial distribution of individuals has a discontinuous behaviour. Principal coordinate analysis (PCO) utilizing the Gower coefficient on standardized data revealed a significantly discontinuous distribution of individuals, such that two different clusters can be defined. The Student's t -test and Tukey test on separate characters, when individuals were classified according to the Costa classification, confirms the significant differences between grouping accessions. This leads to the recognition of two species within the genus in Madeira. Literature and herbarium studies show that these two taxa are conspecific with Semele androgyna (L.) Kunth sensu stricto (s.s.) and Semele menezesi Costa sensu lato (s.l.) . A separated statistical analysis of the S. androgyna cluster shows the possible existence of additional subgroups. Based on field population distribution, ecological behaviour and variation in features, we propose the recognition of two species, S. androgyna (L.) Kunth and S. menezesi (Costa) Pinheiro de Carvalho, and two subspecies S. androgyna (L.) Kunth androgyna Pinheiro de Carvalho and S. androgyna (L.) Kunth pterygophora Pinheiro de Carvalho.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 483–497.  相似文献   

12.
Littorella (Plantaginaceae) is a disjunct, amphibious genus represented by three closely related species. Littorella uniflora occurs in Europe including Iceland and the Azores, L. americana is found in temperate North America, and L. australis grows in temperate South America. Littorella has been recognized in numerous floristic treatments, but its status as a genus has recently been questioned. Rahn (Botanical Journal of the Linnean Society 120: 145-198, 1996) proposed a new phylogeny for Plantaginaceae based on morphological, embryological, and chemical data in which he reduced Littorella to a subgenus of Plantago. This article compares the phylogeny proposed by Rahn to one based on DNA sequence data from the internal transcribed spacer (ITS) region. In our analysis, Littorella forms a strongly supported monophyletic clade sister to Plantago and its recognition at the generic rank appears warranted. Littorella australis is sister to L. americana, and this clade is sister to the European L. uniflora. This more distant relationship between L. uniflora and L. americana provides support for maintaining both taxa at the specific rank and suggests a European origin for Littorella. Our studies also indicate that the monotypic genus Bougueria is deeply nested within Plantago and that its inclusion within Plantago as proposed by Rahn appears justified.  相似文献   

13.
Microsiphum Cholodkovsky (Macrosiphini) is a small genus comprising 11 species and subspecies distributed in the Palaearctic Region. After examination of the collection of the Institute of Zoology (Kazakhstan), Microsiphum diversisetosum sp. n. from Artemisia abrotanum (northern and western Kazakhstan) is described. New synonymies are established: M. nudum Holman, 1961 = M. minus Bozhko, 1963, syn. n., M. ptarmicae Cholodkovsky, 1902 = M. heptapotamicum Kadyrbekov, 2000, syn. n. The taxonomic rank of M. procerae subalpicum Mamontova, 1982 stat. n. and M. jazykovi wahlgreni Hille Ris Lambers, 1947 stat. n. is changed. A key to the known taxa of the genus Microsiphum is given.  相似文献   

14.
Hayataella (Rubiaceae) is a monotypic genus endemic to Taiwan that comprises H. michelloides. In recent years, Hayataella was considered to be synonymous with Ophiorrhiza; however, no specific data have been reported, and the systematic treatment of Hayataella has been unclear. To elucidate the systematic treatment of Hayataella, molecular phylogenetic analyses based on ITS of nrDNA, atpBrbcL, and trnK/matK of cpDNA were conducted with four Ophiorrhiza species. In the Bayesian and the most parsimonious trees, H. michelloides was included in the Ophiorrhiza clade. The monotypic status of Hayataella is, therefore, not considered appropriate, and the combination Ophiorrhiza michelloides (Masam.) H. S. Lo is supported.  相似文献   

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RIVERA NUÑEZ, D., OBON DE CASTRO, C., TOMAS-LORENTE, F., FERRERES, F. & TOMAS-BARBERAN, F. A., 1990. Infrasectional systematics of the genus Sideritis L. section Sideritis (Lamiaceae). A new taxonomic division of the section Sideritis is proposed on the basis of morphological, cytological and chemical characters. The following subsections art-recognized: Grandiflora, Ovata, Camarae, Linearifolia, Gymnocarpae, Stachydioides, Lacaitae, Hirsuta, Chamaedryfolia, Arborescens, Flavovirens, Leucantha, Angustifolia, Serrata and Scordioides . Possible evolutionary pathways are discussed.  相似文献   

16.
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   

17.
DNA sequences from the mitochondrial DNA cytochrome-b gene were used to infer the systematic relationships of 13 species of wood rats (genus Neotoma). Parsimony, likelihood, and neighbor-joining analyses produced similar topologies in most cases and produced six systematic conclusions. First, results of previous studies were supported in the recognition of N. floridana magister as distinct species (N. magister). Second, evidence was provided for the recognition of cryptic species within N. albigula (N. albigula and N. leucodon) and N. mexicana (N. mexicana, N. isthmica, and N. picta). Third, the subgenus Neotoma is composed of four species groups (floridana, lepida, mexicana, and micropus). Fourth, support was provided for placement of N. stephensi within the lepida species group. Fifth, support was provided for the recognition of Hodomys as a separate genus, sister to Xenomys. Sixth, support for the elevation of the subgenus Teonoma to generic status is discussed.  相似文献   

18.
Angel sharks of the genus Squatina represent a group comprising 22 extant benthic species inhabiting continental shelves and upper slopes. In the present study, a comprehensive phylogenetic reconstruction of 17 Squatina species based on two mitochondrial markers (COI and 16S rRNA) is provided. The phylogenetic reconstructions are used to test biogeographic patterns. In addition, a molecular clock analysis is conducted to estimate divergence times of the emerged clades. All analyses show Squatina to be monophyletic. Four geographic clades are recognized, of which the Europe–North Africa–Asia clade is probably a result of the Tethys Sea closure. A second sister group relationship emerged in the analyses, including S. californica (eastern North Pacific) and S. dumeril (western North Atlantic), probably related to the rise of the Panamanian isthmus. The molecular clock analysis show that both lineage divergences coincide with the estimated time of these two geological events.  相似文献   

19.
With c. 85 species, the genus Micranthes is among the larger genera of the Saxifragaceae. It is only distantly related to the morphologically similar genus Saxifraga, in which it has frequently been included as Saxifraga section Micranthes. To study the molecular evolution of Micranthes, we analysed nuclear ribosomal (internal transcribed spacer, ITS) and plastid (trnLtrnF) DNA sequences in a comprehensive set of taxa comprising c. 75% of the species. The molecular phylogenetic tree from the combined dataset revealed eight well‐supported clades of Micranthes. These clades agree in part with previously acknowledged subsections or series of Saxifraga section Micranthes. As these eight groups can also be delineated morphologically, we suggest that they should be recognized as sections of Micranthes. New relationships were also detected for some species and species groups, e.g. section Davuricae sister to sections Intermediae and Merkianae, and M. micranthidifolia as a member of section Micranthes. Species proposed to be excluded from the genus Micranthes for morphological reasons were resolved in the molecular tree in Saxifraga. Many morphological characters surveyed were homoplasious to varying extents. Micromorphological characters support comparatively well the clades in the phylogenetic tree. An updated nomenclature and a taxonomic conspectus of sections and species of Micranthes are provided. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178 , 47–66.  相似文献   

20.
Despite the number of evolutionary, ecological and conservation studies that are conducted on Carabus, the global evolutionary history of the genus remains poorly understood. Here, we analysed 7.5 kilobases of DNA sequence data (six mitochondrial and four nuclear genes) from a worldwide sample of 45% of the known subgenera (99 species and 14 subspecies). We compared the nuclear and mitochondrial phylogenies obtained from Maximum likelihood and Bayesian analyses through topological tests of congruence and dating analyses. Our results mostly corroborate the monophyly of the morphological subgroups of Carabus. However, current morphological and molecular data appear unable to accurately infer the deep branchings within the genus. We show that Carabus originated ca. 16.7-25.1Ma, approximately 25Myr later than previously estimated. Major groups of Carabus are subdivided into clades that diverged from each other in a relatively short period of time around 10Ma (6.6-14.8). This time frame suggests that the present-day distribution of Carabus subgroups may be explained by isolation resulting from Eurasian forest fragmentation brought on by Miocene climate changes and by mountain orogenesis. Finally, we highlight several conflicts between mitochondrial and nuclear topologies that may be explained by mitochondrial introgression.  相似文献   

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