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KATARZYNA MARCYSIAK MAGORZATA MAZUR ANGEL ROMO JOSE M. MONTSERRAT YAKOV DIDUKH KRYSTYNA BORATYSKA ANNA JASISKA PIOTR KOSISKI ADAM BORATYSKI 《Botanical journal of the Linnean Society. Linnean Society of London》2007,155(4):483-495
Juniperus excelsa and J. thurifera are considered to originate from the same ancestor. As a result of occurring in geographically isolated refuges – J. excelsa in SE Europe and SW Asia and J. thurifera in SW Europe and NW Africa – their divergence could have taken place at the end of the Tertiary, with the climate cooling. Juniperus foetidissima occurs in SE Europe and SW Asia in territories shared with J. excelsa and is similar to and sometimes misidentified with it. The occurrence of the latter two species over the same area suggests they should be more similar to each other than to the geographically distant J. thurifera . Four populations of J. excelsa ssp. excelsa , four of J. thurifera and two of Juniperus foetidissima were examined on the basis of features of 10 cones and 10 shoots of 18–36 specimens each. Results of discrimination analysis, Mahalanobis distances and cluster analysis showed great similarity to J. excelsa and J. thurifera , while J. foetidissima was more distant. The results support the hypothesis of a common ancestor of J. excelsa and J. thurifera , but suggest another origin of J. foetidissima . © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 483–495. 相似文献
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Phylogeny and placement of Boganiidae (Coleoptera,Cucujoidea) with a review of Australian and New Caledonian taxa 总被引:1,自引:0,他引:1
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HERMES E. ESCALONA JOHN F. LAWRENCE MAREK WANAT ADAM ŚLIPIŃSKI 《Systematic Entomology》2015,40(3):628-651
A phylogeny of the cucujoid family Boganiidae (Coleoptera) is inferred for the first time based on a parsimony analysis of 102 morphological characters (70 adult and 32 larval). The analysis resulted in a monophyletic Boganiidae divided into two main clades, Boganiinae and Paracucujinae, each supported by a series of synapomorphies. The Boganiinae genera recovered were Afroboganium Endrödy‐Younga & Crowson and Boganium Sen Gupta & Crowson, whereas Paracucujinae includes Paracucujus Sen Gupta & Crowson, Metacucujus Endrödy‐Younga & Crowson, Athertonium Crowson and the New Caledonian Dzumacium caledonicum gen.n. , sp.n. New specimen data and biological information for the Australian taxa are summarized with overviews on biogeography and comments on the fossil Jurassic Parandrexis Martynov (Parandrexidae). Two new species of Boganium, primarily from the Australian mallee are described: B. malleense sp.n. and B. medioflavum sp.n . Boganium malleense is recorded from flowers of Eucalyptus gracilis F. (Myrtaceae). Adults and larvae of Paracucujus rostratus Sen Gupta & Crowson are redescribed. Athertonium parvum Crowson is redescribed and Athertonium williamsi sp.n. is described from coastal New South Wales. Several host records for Athertonium are also presented. 相似文献
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The morphology and the regulation of cortical pattern associated with the cell size, division, and reorganization of Paraurostyla weissei (Stein, 1859) were investigated. The ranges of variation of the Austrian, Polish, and American strains were compared by biometrical analyses. The Austrian population most frequently shows 4 frontal cirri in the anteriormost and 2 in the posterior row, 4 ventral rows, 8 transverse cirri, and 7 dorsal kineties. The oral primordium originates next to the postoral ventral row. The undulating membrane field and 3 frontal-ventral-transverse(FVT)-streaks for the opisthe develop as a result of the dispersion of the basal bodies of 1 or 2 cirri of the 1st ventral row. The farthest-right ventral row is of composite origin from 2 FVT-streaks. Three short dorsal bristle rows originating beside the right marginal row are a constant feature. In reorganizers the oral primordium characteristically possesses a group of kinetosomes extending toward the anterior right, fusing with the undulating membrane field. The development of dorsal primordia always starts in the 3rd dorsal kinety. These results provide important criteria for future species discrimination, if the examination of non-morphological characters supplies evidence that P. weissei is a complex of sibling species. 相似文献
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ADAM SHUTTLEWORTH STEVEN D. JOHNSON 《Botanical journal of the Linnean Society. Linnean Society of London》2012,168(3):278-299
Pollinator‐mediated convergence in floral traits is the fundamental basis for pollination syndromes, but it has seldom been rigorously analysed. Here we synthesize information on a guild of South African plants that are pollinated by functionally similar pompilid wasps in the genus Hemipepsis and investigate the extent of trait convergence in guild members. The guild includes members from three plant families (Apocynaceae, Orchidaceae and Asparagaceae subfamily Scilloideae) and contains remarkably high levels of functional specialization with 18 of the 23 known guild members being pollinated exclusively by Hemipepsis wasps. The distribution of the guild is centred in the moist upland grasslands of eastern South Africa. Qualitative similarities among guild members include dull greenish‐ or brownish‐white flowers, often with purple blotches, mid‐summer flowering, sweet spicy scent and exposed nectar. To assess the extent of convergent evolution within the guild, we compared floral traits of guild members with those of congeneric non‐wasp‐pollinated species. Guild members typically produce moderate volumes (> 4 µL per flower per day) of concentrated (> 50% sugar by weight) sucrose‐dominant nectar. The nectar properties of guild members did not, however, differ significantly from those of congeneric species pollinated by other vectors. Non‐metric multidimensional scaling of scent data for 15 guild members and 17 congeners (obtained through gas chromatography–mass spectrometry of headspace samples and supplemented with published data) yielded little evidence for convergent evolution in the overall scent composition of guild members. However, convergence in floral spectral reflectance was evident in the guild members; in particular, loci for colours of guild members were significantly closer to the guild centroid than loci for colours of congeners, and they formed a distinct cluster in the blue to blue–green region of the hymenopteran colour hexagon. The colours of guild members were also significantly closer to the colour of background vegetation than those of congeneric species, suggesting a role for cryptic colouring in this system. These results confirm convergence in the floral colours of plants that are pollinated by Hemipepsis spider‐hunting wasps, but also suggest that other traits, such as nectar properties, do not necessarily evolve during shifts between pollination systems. Identification of particular scent compounds and non‐sugar nectar constituents that influence wasp behaviour will be essential for illuminating the extent of biochemical convergence in the guild members. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 278–299. 相似文献