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Recent revision of North African specimens of Isoetes velata A. Braun and the closely related taxon I. longissimum Bory, together with Spanish material conventionally designated I. longissimum , suggests that the Spanish specimens constitute a new species, I. fluitans . This is described and illustrated. The North African taxon I. longissimum is probably not specifically distinct from I. velata .  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 231–236.  相似文献   

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A revision of the genus Tecoma in Bolivia based on the author's herbarium research and extensive field observations is presented. Species delimitation is re-evaluated, resulting in the recognition of only four species, one of which, T. beckii J. R. I. Wood, is described as new. Tecoma sambucifolia is treated as var. sambucifolia (Kunth) J. R. I. Wood of the widespread and variable T. stans (L.) Juss., as it can only be distinguished on the basis of minor morphological characters and is not as geographically restricted as has been supposed. Tecoma fulva (Cav.) D. Don is treated as a variable species extending from central Peru to Chile and northern Argentina with six subspecies: ssp. fulva , ssp. guarume (A. DC.) J. R. I. Wood, ssp. tanaeciiflora (Kränzlin) J. R. I. Wood, ssp. arequipensis (Sprague) J. R. I. Wood, ssp. garrocha (Hieron.) J. R. I. Wood, and ssp. altoandina J. R. I. Wood, the latter described as new. The differences between T. tenuiflora (A. DC.) Fabris and the Peruvian T. rosifolia Kunth are discussed. Hybrids are formally recognized in the genus for the first time, and the implications for the accepted corolla morphology and pollination syndromes are discussed. Maps illustrate the geographical distributions of the species. All taxa discussed in the paper are illustrated.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 143–172.  相似文献   

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A multivariate analysis to differentiate morphologically the populations of wild potatoes Solanum cardiophyllum ssp. cardiophyllum and S. cardiophyllum ssp. ehrenbergii was carried out. An analysis of the morphology and the viability of pollen of these potato populations was also made. The results of the morphometric analysis indicate that both subspecies are phenetically different. The pollen grain shape and size in ssp. cardiophyllum are different in northern and southern populations. Pollen diameter is significantly different between subspecies. Based on these results we propose that these taxa should be considered as two separate species.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 415–426.  相似文献   

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A new species, Oxalis ferae Llorens, Gil & Cardona (Oxalidaceae) from the Balearic islands (Spain) is described and illustrated. It is considered to be endemic to Mallorca. The morphological differences between the more closely related taxa of Oxalis section Corniculatae are discussed. IUCN threatened category and observations on the ecology of the populations are noted.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 489–493.  相似文献   

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Two morphotypes of bracken fern in the genus Pteridium Gled. ex Scop. occur in sub-Saharan Africa. The more common and widespread of these is assigned in contemporary systematic treatments to the European subspecies, P. aquilinum (L.) Kuhn ssp. aquilinum . We show that this African form is separable morphometrically and genomically from the European subspecies, and reinstate its earlier name P. aquilinum ssp. capense (Thunb.) C.Chr. The second African bracken, with a more localized tropical distribution mainly in the drainage basins of the Congo and Zambezi River systems, is confirmed as P. aquilinum ssp. centrali-africanum Hieron. ex R.E. Fr. We reject suggestions that this taxon be treated as a full species. Phenetic cluster analysis based on use of Arbitrarily Primed Polymerase Chain Reaction (A-P PCR) and Inter Simple Sequence Repeat (ISSR) fingerprinting of the nuclear genome provides evidence that the two African brackens are more closely related to each other than to other taxa, and sister to a grouping of the European sspp. aquilinum and pinetorum . The two African subspecies share solely with ssp. aquilinum a distinctive chloroplast haplotype carrying a 5-base direct repeat in the rps 4 –trn S region, confirming the close phyletic relationship between sspp. aquilinum , capense and centrali-africanum .  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 311–321.  相似文献   

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Chromosome numbers, karyotypes, meiotic behaviour and pollen analysis are presented for species of Chamaecrista Moench (Leguminosae, Caesalpinioideae, Cassieae ) native to southern Brazil: C. nictitans ssp. patellaria , C. nictitans ssp. disadena , C. repens , C. rotundifolia , C. flexuosa , C. vestita and C. desvauxii . Meiotic behaviour is reported for the first time for all the taxa and was very regular; only bivalents were formed at diakinesis and metaphase I, chromosome disjunction and segregation were regular at anaphases I and II, meiotic indexes were over 99% and pollen fertility was over 92%. Pollen grains were subprolate in C. flexuosa and C. vestita and prolate–spheroidal in the other taxa. Karyotypes were symmetrical in all six species and the data are original, except for C. nictitans ssp. p atellaria. Chromosome number is presented for the first time for C. repens (2 n  = 16) and has been confirmed for the other taxa: 2 n  = 14 for C. desvauxii , 2 n  = 32 for the tetraploid C. nictitans ssp. patellaria and C. nictitans ssp. disadena , and 2 n  = 16 for the other species. These two basic numbers found in the genus, x  = 7 and x  = 8, point to chromosome evolution by dysploidy, which has also been accompanied by polyploidy.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 429–439.  相似文献   

10.
Endemic Cardamine silana from Calabria (southern Italy) previously reported to be related to C. raphanifolia was found to be hexaploid. Morphological characters and AFLP data were analysed to evaluate the degree of differentiation of C. silana from closely related taxa and to find parental taxa of this polyploid. Cardamine apennina from the C. pratensis group was examined as one putative parent, as indicated in previous studies of nuclear ITS sequences, along with other related taxa based on both cpDNA and ITS sequences. Both multivariate morphometric analyses of quantitative characters and evaluation of qualitative morphological characters showed: (1) closest position of C. silana to two diploids: C. acris from the Balkan Peninsula and C. apennina from Central Italy; (2) good extent of morphological separation of C. silana from related taxa; and (3) within C. acris subspecies, C. acris ssp. vardousiae from Central Greece as closest to C. silana . Neighbour-joining tree and PCoA ordinations of AFLP data, as well as patterns of AFLP bands sharing, corroborated results of multivariate morphometrics. This evidence supports an allopolyploid origin of C. silana , with C. apennina and C. acris as parental taxa. Its origin may be dated to Pleistocene glacial events, because of the presumably wider geographical distributions of its parental taxa during more humid periods at that time.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 101–116.  相似文献   

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A synoptic treatment of the Rubiaceae of São Tomé e Príncipe (Gulf of Guinea) is presented based on herbarium collections kept at BM, COI, K and LISC. There are 36 genera and 64 species of Rubiaceae represented in the flora of São Tomé e Príncipe. Identification keys are provided for genera, species and infraspecific taxa. A new combination is made in Chassalia . Twenty-nine taxa are endemic to these islands, two of which are also endemic to Annobon. The conservation status of the endemic taxa is assessed and IUCN categories of threat are proposed for ten taxa. Nineteen taxa of Rubiaceae are considered under threat in São Tomé e Príncipe and ten are considered nearly threatened.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 85–114.  相似文献   

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The west Asian Viola sintenisii W.Becker, described from temperate woodlands of northern Iran and south-western Turkmenistan on the Caspian coast, was long considered a vicariant geographical subspecies of the mainly south European V. alba Besser. The new findings of V. sintenisii in four geographically separated stations in north-eastern Azerbaijan significantly expands its range of distribution. These occurrences are within the range of V. alba ssp. alba . Here the two taxa frequently co-occur but remain distinct and V. sintenisii is therefore justified at species level. It is likely that the two species are also sympatric in the Hyrcanian region, a range previously attributed uniquely to the latter. Viola sintenisii seems to be fairly common in the eastern parts of the Great Caucasus, but there are reasons to suggest that it has there been misinterpreted as V. suavis . The chromosome number of V. sintenisii , 2 n  = 20, is reported here for the first time.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 91–98.  相似文献   

14.
Aethionema rhodopaeum D. Pavlova is described as a new species from the eastern Rhodope Mountains. The plant was found growing only on serpentines, in two localities, at an altitude of approximately 400 m. The localities are typical open habitats with sparsely colonized debris. The plant communities, composed mainly of xerophytes with a mosaic distribution, contain a large number of rare and endemic species for the Bulgarian flora. The new species belongs to the Aethionema saxatile group and is quite close to the species A. saxatile (L.) R. Br., in particular to ssp. creticum and ssp. graecum . The following diagnostic features are given for the new species: inner filament length always greater than half the petal length, lack of teeth of the filaments, longer [2–3(3.5) mm] style than that of A. saxatile subspecies, and dark purple petals. All leaves are broadly elliptical to suborbicular, obtuse, and fleshy. The chromosome number of the new species is 2 n  = 24. The differences between the new species and related taxa are also discussed.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 533–540.  相似文献   

15.
Koelreuteria Laxm., a genus in the tribe Koelreuterieae (Sapindaceae), includes three tree species that are widely recognized as having horticultural merit. The two more closely related species, K. bipinnata Franch. and K. elegans (Seem.) A. C. Sm., are easily distinguished from K. paniculata Laxm. by their bipinnate leaves. In this study, both species were investigated cytogenetically and their karyotypes and heterochromatic patterns were compared. Koelreuteria bipinnata and K. elegans ssp. formosana (Hayata) F. G. Mey. both have 2 n  = 32 but their karyotypes present slight morphological differences when observed using conventional staining. Chromosome banding patterns are reported for the first time for this genus. Both species exhibit terminal heterochromatic blocks, as revealed by C-Giemsa and C-CMA3, but the band size varies between the species. Koelreuteria bipinnata has larger heterochromatic blocks and more GC-rich segments, while in K. elegans ssp. formosana these bands are smaller. The relationship between the karyotype features in these closely related species is discussed.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 451–455.  相似文献   

16.
A synopsis of Acantholimon in Turkey is given on the basis of a revisional study conducted in Turkey by the authors. An account of 52 species, ten subspecies, and 17 varieties is given, including keys to the species, subspecies, and varieties, and a general indication of their distribution, as well as their conservation status in Turkey. Seven new taxa, namely A .  ekimii sp. nov. , A. capitatum ssp. sivasicum ssp. nov. , A. calvertii var. glabrum var. nov. , A. huetii var. breviscapum var. nov. , A. acerosum ssp. longibracteolorum ssp. nov. , A. lycaonicum ssp. cappadocicum ssp. nov. , and A. halophilum var. coloratum var. nov. , are described, together with a few new combinations. A. wiedemannii , A. iconicum , and A. lycaonicum , described from Turkey in the past, but placed under other species as synonyms in the Flora of Turkey , are recognized once again as good species. A. multiflorum and A. parviflorum are given a species status. In Turkey, the presence of A. latifolium , A. araxanum , A. lepturoides , A. hohenackerii , A. senganense , A. fominii , A. petraeum , and A. tragacanthinum is also confirmed.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 397–419.  相似文献   

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Hesperis turkmendaghensis A.Duran & A.Ocak sp. nov. (Cruciferae) is described and illustrated from Anatolia, Turkey. The species grows under mixed forest, open forest and shady slopes in Türkmen Dağı (B3 Eskişehir) in Central Anatolia. It is closely related to H. matronalis L. ssp. matronalis , an endemic confined to Central Anatolia. Diagnostic morphological characters are discussed. Notes are also presented on its ecology, biogeography and conservation status. In addition, the pollen characteristics and seed coat surface of H. turkmendaghensis and H. matronalis are examined by SEM.   © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 239–247.  相似文献   

19.
A new species of Achillea L., Achillea occulta Constantin. & Kalpoutz., from the summit area of Mount Koulochera in south-east Peloponnisos, Greece, is described and illustrated. It belongs to A . sect. Ptarmica and further, to a small group of taxa known under the illegitimate sectional name 'Anthemoideae'. In Greece, A. occulta has no close allies. The taxonomically related taxa, i.e. A. barrelieri (Ten.) Sch. Bip., A. mucronulata Bertol., A. oxyloba (DC.) Sch. Bip. and A. schurii Sch. Bip. are found in the Italian Peninsula, the Alps and the Carpathians. Phytogeographically, the finding of a species with such taxonomic connections in south-east Greece was unexpected. The new species grows in semi-shade, often hidden in suitable limestone rock hollows and the foot of rocks, together with several other Greek endemics. Its chromosome number of 2 n  = 18, counted in root tips, is also reported and illustrated.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 249–256.  相似文献   

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A new species of Arabis L., A. erikii Mutlu sp. nov. , is described and illustrated. The species is restricted to inner Anatolia, south-west of Sivas. It grows on steppes. Diagnostic morphological characters are given for discrimination from the most similar taxa.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 251–256.  相似文献   

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