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1.
Intergeneric hybridization between the endemic New Zealand species Helichrysum lanceolatum and Anaphalioides bellidioides (Asteraceae: Gnaphalieae) at two Banks Peninsula populations was investigated by DNA sequencing and amplified fragment length polymorphism fingerprinting. Crosses in both directions have contributed to the generation of the F1 hybrids, but in the study season hybridization was far more common with H. lanceolatum as the maternal parent. F1 hybrids have reduced, but considerable, fertility and seed collected from them includes back-crosses. Two hybrid plants sampled from the wild appear to be back-crosses to H. lanceolatum. Despite back-crossing, introgression was not demonstrated and is at most limited in scope. These results also corroborate important roles for small population size and rarity in the formation of hybrid lineages in New Zealand's everlastings.  © 2007 Landcare Research New Zealand Ltd. Journal compilation © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 89–98.  相似文献   

2.
Wild intergeneric hybrids are recorded among six genera in the New Zealand Gnaphalieae, but little evidence substantiating their identity has been published. In this paper we evaluate the identity of putative hybrids between two species of Gnaphalieae endemic to New Zealand, Anaphalioides bellidioides and Ewartia sinclairii . The two species are occasionally sympatric in the north-east of the South Island and wild putative hybrids are rarely encountered. To test the hybridity hypothesis, specimens from nine putative hybrids were collected from one site and analysed for 76 morphological characters. The putative hybrids possessed predominantly intermediate or parental character states in comparison with A. bellidioides and E. sinclairii . Extreme traits were less common and a single novel character state was recorded in two hybrids only. Non-metric multidimensional scaling of dissimilarities derived from both continuous and discrete characters was strongly supportive of the hybridity hypothesis. Canonical discriminant analysis of the continuous characters was supportive for some putative hybrids only, in part reflecting the possession of extreme states in characters with high loadings. One of the putative hybrids was strongly indicated to be a backcross with A. bellidioides . The taxonomic treatment of cross-compatible genera is discussed.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 59−75.  相似文献   

3.
A survey of morphological characters is carried out for Stapeliopsis . The information obtained from this is combined with molecular data from the plastid trn L-F DNA region and ITS1 of the nuclear encoded 18S−26S rRNA cistron, to obtain a hypothesis of the evolutionary relationships among the species. It is shown that Stapeliopsis is monophyletic in a combined molecular and morphological analysis. Stapeliopsis is sister to a clade containing Huernia , Orbea and Tromotriche . The species of Stapeliopsis group into two clades. One contains S. khamiesbergensis , S. neronis and S. urniflora , and this is highly supported. The remaining species fall into an unsupported clade in which S. exasperata is sister to the others. The genera Hermanschwartzia Plowes and Neopectinaria Plowes are rejected. It is shown that a synapomorphy for Stapeliopsis is the laterally flattened inner corona-lobes, which touch the anthers only at their bases. Eight species of Stapeliopsis are recognized, with no subgeneric divisions.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 125–155.  相似文献   

4.
We combined nearly complete sequences of large (LSU) and small (SSU) subunit rDNA from 32 flatworm species to estimate the phylogeny of the Platyhelminthes using maximum parsimony, maximum likelihood and Bayesian inference methods. Rooted against the Catenulida, combined evidence trees offered no support for the Revertospermata, which was also rejected by constraint analysis. Generally, nodal support was higher for groupings estimated from the combined data partitions and all methods of analysis provided congruent estimates of phylogeny. The Monogenea and Proseriata were resolved as monophyletic, rejecting previous suggestions of paraphyly based on SSU and partial LSU data sets and thus supporting widely accepted morphological synapomorphies. Monophyly of the Neodermata was supported and its sister group was a clade of neoophoran 'turbellarians' to the exclusion of the Proseriata which in turn was more basal. Taxa with similar spermatology to the Neodermata ( Ichthyophaga , Notentera , Urastoma and Kronborgia ) were the sister group to Tricladida + Prolecithophora, which in turn were sister to the Rhabdocoela. Polycladida + Macrostomida + Lecithoepitheliata was the earliest divergent offshoot of the Rhabditophora. Among the Neodermata, the Cercomeromorphae (Cestoda + Monogenea) was not supported, whereas Cestoda + Trematoda was well supported. Although there is no known synapomorphy for this latter grouping, our data highlight problems associated with the 'cercomer theory' and we reject putative homologies regarding neodermatan 'cercomers' that have been sustained in the literature without careful scrutiny.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 78, 155–171.  相似文献   

5.
The taxonomy of the New World species of the genus Trichadenotecnum is revised. A total of 44 species, including 29 new species, were treated. These species are classified into 12 monophyletic species groups, eight of them newly proposed here. Two species previously assigned to Trichadenotecnum , T. pichincha New & Thornton and T. sylvaticum Turner, are recognized as not belonging to this genus. Phylogenetic relationships among 16 previously and presently proposed species groups are estimated based on a data matrix of 58 morphological characters. Trees from these analyses support monophyly of Trichadenotecnum and the proposed species groups. The New World species were divided into three major clades. Based on the phylogenetic hypothesis and distributional pattern of the species groups, the biogeographical history of the New World Trichadenotecnum is discussed.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 153 , 651–723.  相似文献   

6.
Specimens belonging to Tortula subulata complex ( T. inermis , T. mucronifolia and T. subulata ) were analysed using a combination of morphometric methods based on quantitative characters [principal component analysis (PCA), discriminant analysis (DA); 76 samples)] and molecular methods (ITS1 – 5.8S rRNA gene and ITS2; 47 samples) to assess patterns of morphological and molecular differentiation within this complex of taxa. The study shows that four species can be recognized: T. mucronifolia , T. subulata , T. inermis and T. subulata var. angustata with bistratose border, which is elevated to the species rank as T. schimperi nom. nov. The most valuable quantitative characters for identification of these species are the strata number of the marginal laminal cells, the ratio of middle marginal laminal cell width/middle marginal laminal cell length, basal membrane of peristome length, middle laminal cell width and papillae number on the middle laminal cells. The internal transcribed spacer (ITS) data suggest that this group of taxa is not monophyletic, T. mucronifolia being close to Protobryum bryoides (= Tortula protobryoides ). The remaining species seem to be a monophyletic group, T. schimperi being the sister group of the clade composed by T. inermis and T. subulata . T. subulata is considered to be of high morphological variability, for which ITS sequences did not resolve the internal relationships.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 333–350.  相似文献   

7.
This paper studies the speciation of two land snail species in south-east France. By using two mitochondrial and one nuclear gene, the species are shown to be sister species within the larger clade of western European Candidula species. The species never occurred syntopically, but a narrow contact zone population was identified. Recent range expansions inferred from phylogeographical methods indicated that the present day distributions are not limited by the colonization capacity of the species. Analysis of environmental variables suggested distribution along an ecotone. The gastropod community is also correlated to this gradient. Morphometric shell analysis showed that the divergence between the sister species is a result of desiccation-resistant shell characters. We therefore conclude that the cause for the ecological speciation is most probably the establishment of the Mediterranean climate ≈ 3.2 mya. A model of ecological speciation with a moving ecotone is put forward.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79, 611–628.  相似文献   

8.
Hexabathynella is the only cosmopolitan genus of the order Bathynellacea (Crustacea). The known species number 18, found in Europe (9), Africa (1), South America (2), North America (3) and Australia and New Zealand (3). Phylogenetic analysis suggests that the least derived species are those from South America and the most derived those from the Iberian Peninsula, North America and Australia. The five species with the most plesiomorphic characters occur in salt or brackish water, which supports a marine origin for the genus. Phylogenetic and biogeographical analyses suggest that the distribution of the genus can be explained by dispersion and a double vicariant biogeographical model based on plate tectonics and the evolution of the Tethys during the Mesozoic and Cenozoic.  © 2003 The Linnean Society of London . Biological Journal of the Linnean Society , 2003, 78 , 457–466.  相似文献   

9.
Comprehensive taxonomic sampling can vastly improve the accuracy of phylogenetic reconstruction. Here, we present the most inclusive phylogenetic analysis of Arvicolinae (Mammalia, Rodentia) to date, combining all published cytochrome  b gene sequences of greater than 1097 bp and new sequences from two monotypic genera. Overall, the phylogenetic relationships between 69 species of voles and lemmings, representing 18 genera and 10 tribes, were studied. By applying powerful modern approaches to phylogenetic reconstruction, such as maximum likelihood and Bayesian analysis, we provide new information on the early pulse of evolution within the Arvicolinae. While the position of two highly divergent lineages, Phenacomys and Ondatra , could not be resolved, the tribe Lemmini, appeared as the most basal group of voles. The collared lemmings (Dicrostonychini) grouped together with all of the remaining tribes. The two previously unstudied monotypic genera Dinaromys and Prometheomys form a moderately well-supported monophyletic clade, possibly a sister group to Ellobius (Ellobiusini). Furthermore, with one exception, all tribes ( sensu Musser & Carleton, 2005) proved to be monophyletic and can thus be regarded as meaningful evolutionary entities. Only the tribe Arvicolini emerged as paraphyletic in both analyses because of the unresolved phylogenetic position of Arvicola terrestris . Steppe voles of the genus Lagurus were solidly supported as a sister group to the Microtus and allies clade.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 825–835.  相似文献   

10.
A new family of eupodine Prostigmata, Eriorhynchidae fam.n. , is established to accommodate Eriorhynchus gen.n. , and five species from Australia: E.australicus (Womersley), E.hades sp.n. , E.ramosus sp.n. , E.walteri sp.n. and E.womersleyi sp.n. The new family is unique in the possession of 15–34 setae on the gnathosomatic base, a naso-prodorsal process with 9–28 setae and a palp tibia with 6 or 7 setae. A key to the families of Eupodoidea is provided. A cladistic analysis of twenty-seven eupodoid species from Australia and New Zealand is presented. Results indicate that the genus Eriorhynchus gen.n. (thus Eriorhynchidae) is monophyletic, and the Australian and New Zealand species of Halotydeus Berlese, Penthaleus C. L. Koch, Rhagidia Thorell and Stereotydeus Berlese form separate monophyletic goups, while the Penthaleidae are not monophyletic. The new family Eriorhynchidae is a sister group to a clade consisting of Penthaleus and Chromotydaeus quartus Qin & Halliday.  相似文献   

11.
Gondwanan biogeography has fascinated zoologists and botanists for over a century, but most biogeographical work has used continent-scale areas as analytical units. More finely resolved patterns, as can be obtained from small invertebrates with limited dispersal abilities, will be obscured in those studies. A common case is treating Australia as a single biogeographical region. In the present study, the necessity of splitting Australia into multiple microareas is demonstrated using centipedes as an example. The lithobiomorph centipede Paralamyctes is distributed on fragments of Gondwana, with species in southern Africa, Madagascar, southern India, Patagonia, eastern Australia, and New Zealand. A cladogram for Paralamyctes is based on morphology and sequences for four molecular markers for 30 terminals that sample 20 of 26 known ingroup species and four outgroups. Analysis with direct optimization across a range of indel costs and transversion : transition cost ratios identifies two main clades: Paralamyctes ( Paralamyctes ) unites species from southern Africa, Madagascar, tropical and warm temperate Australia, and New Zealand. The other group includes the temperate Australian/New Zealand Paralamyctes ( Haasiella ) and Paralamyctes ( Thingathinga ) and a Chilean clade. Subtree analysis finds that different parts of Australia have closest affinities to other Gondwanan fragments, and some of these relationships (such as that between north Queensland and New Zealand) are based on taxonomically stable clades. Area delimitation for large continental fragments should use sufficiently fine resolution to test the 'monophyly' of those fragments and attempt to eliminate spurious geographical paralogy.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 65–78.  相似文献   

12.
The Gnaphalieae are a group of sunflowers that have their greatest diversity in South America, Southern Africa, and Australia. The objective of this study was to reconstruct a phylogeny of the South African Gnaphalieae using sequence data from two noncoding chloroplast DNA sequences, the trnL intron and trnL/trnF intergenic spacer. Included in this investigation are the genera of the Gnaphalieae from the African basal groups, members of the subtribes Cassiniinae, Gnaphaliinae, and Relhaniinae, and African representatives from the large Old World genus Helichrysum. Results indicate that two Gnaphaloid genera, Printzia and Callilepis, should be excluded from the Gnaphalieae. In most trees the Relhaniinae s.s. (sensu stricto) and some of the basal taxa comprise a clade that is sister to the remainder of the tribe Gnaphalieae. The Relhaniinae, which are restricted to Africa, are not a monophyletic group as presently circumscribed, nor are the South African members of Helichrysum, the Cassiniinae and Gnaphaliinae. There is general agreement between our molecular analysis and that of morphology, particularly in the terminal branches of the trees.  相似文献   

13.
Granite outcrops represent an isolated island habitat and, in ancient landscapes, may harbour species with complex evolutionary histories. Phylogenetic analysis of these species may reveal the influences of evolutionary processes over long time frames. Phylogenetic relationships from chloroplast and nuclear genome analysis were investigated in Eucalyptus caesia , a bird-pollinated mallee endemic to granite outcrops in the South-western Australian Floristic Region. The results obtained revealed high population and haplotype divergence, suggesting restriction to the specific habitat of granite outcrops over long time frames with genetic drift as the most significant evolutionary force. The hypothesis of derivation of ssp. magna from ssp. caesia was not supported by the pattern of diversity in either the chloroplast or the nuclear genome and the two subspecies were not monophyletic. Eucalyptus caesia displays significant clonality yet little evidence of inbreeding depression, suggesting deleterious mutations causing inbreeding depression have been purged.  © 2008 Department of Environment and Conservation. Journal compilation © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 177–188.  相似文献   

14.
A new genus and species in the eucalypt group of the Myrtaceae is described. Stockwellia quadrifida D.J. Carr, S.G.M. Carr & B.Hyland gen. et sp. nov. is a rainforest tree of restricted distribution on the Atherton Tableland, North Queensland, Australia. Molecular data suggest that it is the sister taxon to Eucalyptopsis and this is supported by morphological characters. The prolonged hypanthium and reduced perianth appear to be synapomorphies for these two genera and the circumscissile hypanthium a synapomorphy shared with Allosyncarpia . Stockwellia differs from Eucalyptopsis by the distinct, albeit reduced, perianth and the hypanthium splitting into four segments at anthesis. The relationship of these two genera indicates an historical biogeographical link between New Guinea and the Queensland wet tropics region.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 415–421.  相似文献   

15.
A new species of Helichrysum Gaertn., H. orbicularifolium Sümbül, R. S. Göktürk & O. D. Düşen sp. nov. , is described and illustrated. The species is restricted to the south Anatolia Province, Antalya, Turkey, growing in humid calcareous rock crevices and on limestone cliffs. The species is compared with the closely related H. chasmolycicum . © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 251–254.  相似文献   

16.
A new subfamily, Delturinae, is described to accommodate the loricariid catfish genera Delturus Egenmann & Eigenmann, 1889 and Hemipsilichthys Eigenmann & Eigenmann, 1889, a clade recently demonstrated to be the sister group of all remaining loricariids except Lithogenes . The genus Hemipsilichthys is restricted to three species, H. gobio (Lütken, 1874), its sister species H. papillatus Pereira et al ., 2000, and H. nimius Pereira et al ., 2003. Relationships among species of Delturus were not resolved and a new species, D. brevis , is described from the Rio Jequitinhonha basin in eastern Brazil. The geographical distribution of Delturinae, exclusively on the south-eastern Brazilian Shield, indicates that south-eastern Brazil acts as either a refugium for basal loricariid taxa or a point of origin for the Loricariidae. Lectotypes are designated for D. parahybae Eigenmann & Eigenmann, 1889 and Plecostomus angulicauda Steindachner, 1877. Keys are presented for subfamilies of Loricariidae and for genera and species of Delturinae. Diagnoses are provided for all delturine clades and species.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 277–299.  相似文献   

17.
We assessed relationships between acoustic frequency, body mass, and habitat in tinamous. This monophyletic group of primitive birds comprises c. 47 ground dwelling species whose habitats range from dense humid forest to open grasslands. The relationship between frequency and body mass was found to be negative, while the songs of open-habitat species exhibited higher frequencies and a wider bandwidth than the closed-habitat ones. Residual variation in song frequency, after controlling for the effect of body mass and phylogeny, tends to differ among habitats. However, a statistical test of this pattern was not possible because of the existence of only five pairs of sister species differing in habitat. In spite of this, positive contrasts of bandwidth were associated with positive contrasts of habitat, confirming that songs of open-habitat species have a wider bandwidth than those of their more closed habitat relatives.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 77 , 423–430.  相似文献   

18.
The cladistic relationships of endemic Commidendrum (four species) and Melanodendron (one species) from St Helena were inferred from sequences of ITS1 and ITS2 of nuclear ribosomal DNA. Despite showing a range of morphological and ecological variation, the four species of Commidendrum , C. spurium , C. robustum , C. rotundifolium , and C. rugosum , form a closely related monophyletic group with percentage sequence divergence between 0.2 and 0.9%. Melanodendron integrifolium is sister to Commidendrum indicating that the two genera may have evolved from a common ancestor that arrived in St Helena via a single dispersal event. The closest relatives of Commidendrum and Melanodendron appear to be South African, in the predominantly shrubby genus Felicia , although further sampling of South African Astereae is required. We discuss the evolution and adaptive radiation of these rare and threatened species with particular reference to the possible role of heterochrony.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 69–83.  相似文献   

19.
A cladistic analysis that includes representatives of all recent genera of mysticetes and several fossil species that were previously referred to the family Cetotheriidae, with tooth-bearing mysticetes and an archaeocete as an outgroup, is presented here. The result of this analysis forms the base of a revised classification of Mysticeti. Cetotheriidae is redefined as a monophyletic family, which includes the genera Cetotherium , Piscobalaena , and a new subfamily Herpetocetinae, including Herpetocetus , Nannocetus , Metopocetus , and Cephalotropis . Eschrichtiidae is the closest sister taxon to Cetotheriidae. A few species are referred to Eomysticetoidea, whereas the remaining species that were previously referred to Cetotheriidae appear in four clades that branch off from the lineage leading to Balaenopteridae. These are a Mauicetus clade and three clades that are named as new families Aglaocetidae, Pelocetidae, and Diorocetidae.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 150 , 875–894.  相似文献   

20.
New findings are given for the Astragalus sect. Incani , which occurs within the area covered by the Flora of Iran. Astragalus wojciechowskianus Ranjbar is described as a new species. A. procerus Boiss. & Hausskn . , A. cottonianus Aitch. & Baker, A. achundovii Grossh., A. orduabadensis Grossh. and A. glaucophyllus Bunge are reported as new records for the flora of Iran .   © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 443–447.  相似文献   

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