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1.
Essential oils of B. articulata, B. crispa, B. microcephala, Baccharis milleflora, B. myriocephala, B. stenocephala, B. trimera and B. usterii, all of sect. Caulopterae, have been analyzed by GC and GC/MS. Despite the morphological similarity among these species, differences in composition of their essential oil obtained by hydrodistillation and hexane extract could be observed. Special attention was given to Baccharis trimera and B. crispa since their differentiation during early stages is not possible due to the absence of synflorescences. Carquejyl acetate is suggested as a marker for Baccharis trimera, and a fast method of detection of this compound is given.  相似文献   

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Seed protein electrophoresis confirms the existence of polymorphism among hexaploid populations ofFestuca arundinacea. Both protein and morphological results suggest thatF. pratensis andF. arundinacea should retain independent specific status. High protein homology of these two species withF. gigantea points towards phylogenetic links between these taxa.  相似文献   

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Asplenium basiscopicum is described, illustrated, and compared to the most similar species,A. purpurascens.  相似文献   

4.
Phylogenetic analysis of nrDNA ITS and trnL (UAA) 5 exon-trnF (GAA) chloroplast DNA sequences from 17 species ofPelargonium sect.Peristera, together with nine putative outgroups, suggests paraphyly for the section and a close relationship between the highly disjunct South African and Australian species of sect.Peristera. Representatives fromPelargonium sectt.Reniformia, Ligularia s. l. andIsopetalum (the St. Helena endemicP. cotyledonis) appear to be nested within thePeristera clade. The close relationship between the South African and AustralianPeristera is interpreted as being caused by long-range dispersal to Australia, probably as recent as the late Pliocene.  相似文献   

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Magnolia polytepala Law, R.Z. Zhou & R.J. Zhang sp. nov. (Magnoliaceae) a new species from Fujian, south-east China, is described and illustrated. The species was found growing only in the evergreen broad-leaved forests of Mount Wuyishan at altitudes of 500–1200 m. Notes are also presented on the phenology and conservation status of the new species. It is closely related to Magnolia liliiflora Desr., but differs from the latter in its stunted habit (less than 2 m tall) and tepals, which are more numerous (12–16) and not contorted at the base.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 289–292.  相似文献   

7.
Difficulties in delimiting well-defined entities in the dogroses (Rosa sect.Caninae) has resulted in very variable taxonomic treatments. The present study was undertaken to provide a background for taxonomy as well as plant breeding. Morphometric diversity was analysed on seedlings obtained from field collections in South Sweden of three species,Rosa dumalis, R. rubiginosa andR. villosa. A canonical variates analysis showed that the three species are relatively distinct whereas two subspecies ofR. dumalis were less well discriminated. Analyses of variance demonstrated that intraspecific variation is pronounced inR. dumalis and, to a lesser extent, inR. villosa.  相似文献   

8.
Justicia brevipedunculata, a new species ofJ. sect.Ansellia endemic to Tanzania, is described and illustrated. Detailed palynological information is given, and relationships to other species of the section are discussed.  相似文献   

9.
Pothos crassipedunculatus Sivadasan & Mohanan (Araceae), a new species closely related to the SW. Indian endemic and little known speciesP. thomsonianus Schott is described. It is characterized by the the non-ligulate, shortly vaginate petiole, thickly peduncled inflorescence, broadly ovate spathe and a sessile spadix. It is included in ser.Brevivaginati Engler of sect.Allopothos Schott.  相似文献   

10.
A new species of the genusHypericum, Hypericum carpaticum Mártonfi, is described from Slovakia. It is pentaploid (2n=40) with morphological and chemical features that are most similar to the tetraploid speciesH. dubium Leers from western Europe. The species is most likely of hybridogenous origin, arising as a result of hybridization betweenH. maculatum Crantz andH. perforatum L. It seems that consequent speciation processes and stabilization by inherited apomixis (fromH. perforatum) allowed it to reproduce successfully and to enlarge its distribution area. According to recent knowledge of its distribution, it is necessary to consider it endemic to the Volovské vrchy Mts. in the Carpathians. With regard to its scarcity it merits EN status according to the IUCN criteria.  相似文献   

11.
Among the suffruticose cabbages of Brassica sect. Brassica, a new species from Sicily, named B. raimondoi, is described and illustrated. It is a chasmophyte restricted to some steep limestone cliffs near Taormina (NE Sicily) and is morphologically related to B. incana, with which it shares densely hairy, broad, amplexicaul leaves and winged petioles, but differs principally in its white corolla, larger floral pieces, more developed stigmatic papillae, shorter siliquae with keeled valves and a smaller, seedless beak, smaller seeds differing in testa microsculpture. A key for the identification of the currently known Sicilian taxa of the section is provided.  相似文献   

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Two new species of Justicia L. are described: Justicia ukagurensis Hedrén and Justicia sulphuriflora Hedrén, both from crystalline mountains of eastern Tanzania.  相似文献   

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Rafael Lira  Michael Nee 《Brittonia》1999,51(2):204-209
Sechium mexicanum is described as a new species ofSechium sect.Frantzia. It differs from the remaining species of the section by several features of the inflorescences and staminate flowers, the obovoid and completely unarmed fruits, and pollen grains with 9–10 narrow, poorly defined colpi. It is endemic to Mexico and the first member of sect.Frantzia to be recorded outside of Central America. It grows at 900–2300 m in mesophilous forests and in oak and pineoak forests in the states of Hidalgo, Puebla, Querétaro, and Veracruz.  相似文献   

17.
Cladonia (sect. Cocciferae , subsect. Ochroleucae) norvegica T0nsb. & Holien sp. nov., is closely related to C. bacilliformis (Nyl.) DT. & Sarnth. but is morphologically, chemically, and ecologically distinct. Superficially it may resemble C. (sect. Cladonia) coniocraea auct., which is often growing with it. C. norvegica is known from Norway only.  相似文献   

18.
A new species of Mimosa section Mimosa, Mimosa eurystegia, which is apparently endemic to Paraná in southern Brazil, is described and illustrated. This species is distinguished by plurinerved leaflets and papyraceous, plurinerved, orbicular, amplexicaul stipules. Morphological distinctiveness of this new Mimosa and its relationships with allied species are discussed. Phenological, geographical and ecological data are presented, in addition to a key to the species of Mimosa subser. Sparsae.  相似文献   

19.
Hieracium busambarense (Asteraceae), a new species from calcareous-dolomite cliffs of Rocca Busambra (western Sicily, Italy) is described and illustrated here.  相似文献   

20.
描述了中国云南北部的金丝桃属Hypericum L.(藤黄科)两个新种,即楚雄金丝桃H. fosteri N. Robson和漾濞金丝桃H. wardianum N. Robson.二者均与短柱金丝桃H. hookerianum Wight & Arn.相近.楚雄金丝桃为一地方特有种,目前仅在模式地点发现;漾濞金丝桃在缅甸东北部还有分布.二者主要以蒴果伸长,非卵状近球形,萼片无中脉而有别于短柱金丝桃.此外,将宽萼金丝桃H. latisepalum (N. Robson) N. Robson从亚种提升为种;将变异较大的纤枝金丝桃H. lagarocladum N. Robson划分为两个亚种,即叶较宽、具有开张习性的原亚种纤枝金丝桃H. lagarocladum ssp. lagarocladum和叶较窄、更为直立的新亚种狭叶金丝桃H. lagarocladum ssp. angustifolium N. Robson.  相似文献   

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