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1.
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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New information on (1) Hippophae goniocarpa Y.S. Lian et al . ex Swenson et Bartish and (2) H. goniocarpa ssp. litangensis (Lian et X.L. Chen ex Swenson et Bartish) Lian et K. Sun from China is provided and illustrated. Based on morphological characters and distribution, H. litangensis Y.S. Lian et X.L. Chen ex Swenson et Bartish is re-described as a subspecies. H. goniocarpa (including ssp. litangensis ) is a distinct species and should be placed in Section Gyantsensis of Hippophae , although it has been suggested that sspp. litangensis and goniocarpa are the result of hybridization between H. rhamnoides ssp. sinensis and H. neurocarpa ssp. neurocarpa , and H. rhamnoides ssp. yunnanensis and H. neurocarpa ssp. stellatopilosa , respectively. The type subspecies of H. goniocarpa is distributed in Songpan and Hongyuan Counties of Sichuan Province and Qilian County of Qinghai Province, at 3500–3750 m, whereas ssp. litangensis is found only in Jiawa, Litang County, Sichuan Province at c . 3700 m. A key including the four taxa of sect. Gyantsensis is provided.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 425−430.  相似文献   

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Contemporary systematic treatments of the Central and South American bracken ferns in the genus Pteridium Gled. ex Scop. recognize morphotype caudatum as either a full species or a variety of P. aquilinum (L.) Kuhn. Geographically representative sporophytes of morphotype caudatum , including the type in the Linnaean Herbarium, are shown using spore size, guard-cell length and morphology of the cells of the false indusium to be tetraploid (based on 4 n  = 208). DNA fingerprinting of field-collected Venezuelan samples supports the generalization that morphotype caudatum is a fertile allotetraploid containing genomic elements otherwise distinctive of the southern hemisphere diploid P. arachnoideum (Kaulf.) Maxon, together with elements characteristic of northern hemisphere diploids including the North American P. aquilinum var. pubescens Underw. and P. aquilinum var. pseudocaudatum (Clute) A. Heller. Evidence of genetic isolation from taxa with overlapping distributions, as well as morphological, biochemical and ecological data, validate recognition of P. caudatum (L.) Maxon at species level. Heterogeneity observed within P. caudatum is consistent with multiple origins through independent hybridization events. Pteridium caudatum is strikingly analogous to the tropical Asian/Australasian allotetraploid P. semihastatum (N. Wallich ex J. G. Agardh) S. B. Andrews [= P. yarrabense (Domin) N. A. Wakef.].  © 2002 The Linnean Society of London . Botanical Journal of the Linnean Society , 2002, 140 , 237−248.  相似文献   

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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   

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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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The molecular biogeography of the disjunctly distributed and morphologically highly variable species Saxifraga paniculata Mill. was analysed using amplified fragment length polymorphism (AFLP) and chloroplast microsatellites. The study comprised 77 samples from mountain regions in Europe and North America throughout the complete range of distribution. AFLP data revealed clear genetic differentiation between samples from the Arctic, the Caucasus, and the eastern European mountains. Samples from the Alps were divided into two groups. One group clustered with the samples from central Europe and the Pyrenees, whereas another group with individuals from southern Norway. AFLP diversity was lowest in the Arctic and highest in the Alps. Chloroplast microsatellite analysis revealed eight haplotypes but no unequivocal phylogeographical pattern. However, haplotype diversity was highest in the Alps and central Europe whereas, in the Arctic, only few widespread haplotypes could be found. The results indicate in situ survival of S. paniculata in the Caucasus, the eastern European mountains, and the Alps. The Arctic has presumably been colonized postglacially from North American refugia south of the ice shield. Southern Norway and the Pyrenees have most likely been colonized from two phylogeographically different groups in the Alps. The origin of the central European samples remains ambiguous. In situ survival seems to be as possible as several postglacial recolonization events from the Alps. The obtained molecular data clearly support the subdivision of S. paniculata into three subspecies: ssp. cartilaginea from the Caucasus, ssp. laestadii from northern Norway, Iceland, and North America, and ssp. paniculata from the other geographical regions.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 385–398.  相似文献   

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Paeonia (Paeoniaceae) in the Caucasus   总被引:1,自引:0,他引:1  
The taxonomy of the genus Paeonia in the Caucasus has been controversial, with recognized species varying in number from one to 13. The taxonomic history of Paeonia in this area is reviewed (including an analysis of the characters used by previous authors) based on extensive field observations, population sampling and critical examination of a large number of herbarium specimens. The results show that Paeonia may be divided into three groups. The P. intermedia group is known from only a single population. In the P. tenuifolia group, all the characters used for distinguishing the three previously recognized species were found to be polymorphic. In the P. daurica group, petal colour, shape and size of leaflets, and indumentum of leaflets and carpels were used to distinguish nine species, but these characters were found to be polymorphic or continuous in variation, and thus can only be used for infraspecific classification. Thus, three species are recognized: P. intermedia , P. tenuifolia and P. daurica . The last species is further divided into five subspecies: sspp. coriifolia , wittmanniana , mlokosewitschii , macrophylla and tomentosa stat. nov .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 143 , 135–150.  相似文献   

11.
On the basis of the study of c . 1100 herbarium specimens, field observations and molecular (ITS, AFLPs) evidence, Primula sect . Auricula is classified into two subsections, 25 species and six subspecies. Primula auricula L. ssp. widmerae (Pax) L. B. Zhang stat. nov. , P. auricula Linn. ssp. tatriaca L. B. Zhang ssp. nov. , and P. latifolia Lapeyr. ssp. cynoglossifolia (Widmer) L. B. Zhang stat. nov. are newly described or combined; P. auricula s.l. is divided into two species: P. auricula Linn. and P. balbisii Lehm., representing the northern and the southern populations of P. auricula s.l. resolved in the molecular study, respectively; P. cottia Widmer and P. balbisii Lehm. are recovered from synonymy; P. grignensis D. M. Moser and P. pedemontana E. Thomas ex. Gaudin ssp. iberica Losa et P. Monts. are synonymized with P. hirsuta All. and P. pedemontana , respectively; P. clusiana is postulated to be an allopolyploid species. Phylogenetic relationships in the section are discussed based on morphological and molecular variation and geographical distribution.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 1–26.  相似文献   

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The delimitation of species is a major issue in systematic biology and has been a re-emerging discipline in the last decade. A number of studies have shown that the use of multiple data sets is critical for the identification of cryptic species, particularly in groups with complex evolutionary histories. Liolaemus monticola is a montane lizard species distributed in central Chile (32°–42°S), with four described subspecies in a latitudinal gradient from north to south: L. m. monticola , L. m. chillanensis , L. monticola ssp. and L. m. villaricensis . In order to test the systematic status and phylogenetic relationships of the taxa included in the L. monticola group, we analysed morphological (morphometric and meristic) and molecular (allozyme and mitochondrial DNA) data sets. The results of the morphological analyses showed that meristic variables correctly assigned individuals with higher accuracy than did morphometric characters. The results of the analyses of allozyme data revealed eight diagnostic loci that are evidence for significant differences among the four L. monticola subspecies. Phylogenetic analyses with mitochondrial DNA data, including additional species, showed that the L. monticola group is polyphyletic. We postulate that the four current subspecies represent independent evolutionary lineages and must be raised to the specific level as L. monticola , L. chillanensis and L. villaricensis . The taxonomic status of the unnamed L. monticola ssp. remains unresolved, although we provide a preliminary proposal.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 635–650.  相似文献   

13.
In Cyclamen subgenus Psilanthum , previous authors have recognized three species ( C. repandum, C. balearicum and C. creticum ), with C. repandum subdivided into three subspecies (ssp. repandum , ssp. peloponnesiacum and ssp. rhodense ), and two varieties (var. vividum and var. peloponnesiacum ) within C. repandum ssp. peloponnesiacum . To examine the validity of this classification and the degree of morphological differentiation among closely related endemic taxa with disjunct distributions, we undertook analyses of three quantitative and eight qualitative morphological traits of flowers and leaves, most of which have previously been used without statistical comparison in the classification of the different taxa. Cyclamen balearicum showed high levels of morphological differentiation from all other taxa in subgenus Psilanthum consistent with its specific status. In contrast, morphological differentiation between C. creticum and subspecies of C. repandum was similar to that among the three subspecies of C. repandum . When compared with a recent molecular phylogeny of this subgenus, our results suggest that C. creticum may best be described as a geographical subspecies of C. repandum . The two varieties of C. repandum ssp. peloponnesiacum showed few significant differences for individual traits and their overall morphology is very similar to each other. The morphology of plants at three sites on Corsica strongly suggest, consistent with molecular data, the occurrence of hybrid populations between C. balearicum (outside of its previously recognized distribution) and local C. repandum .  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 133–144.  相似文献   

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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   

15.
The peony in the Crimea of Ukraine and its allied populations have been variously taxonomically treated, as Paeonia daurica Andrews or P. mascula ssp. triternata (Pall. ex DC.) Stearn & P. H. Davis. Supported by the National Geographical Society, we have conducted extensive field observations and population sampling of this group in Turkey. In addition, relevant herbarium specimens from the herbaria B, BEO, BM, BUCA, E, G, GZU, K, P, SA, SOM, UPA, and WU were critically examined. Principal coordinate analysis was performed using MVSP-Version 3.13b analysis software. As a result, P. daurica was shown to be clearly differentiated from P. mascula in the number of leaflets/segments of the lower leaves and the shape of the terminal leaflets. P. daurica is diploid, except for three local tetraploids in the Caucasus, whereas P. mascula is consistently tetraploid. The two units were not found growing together, even in southern Turkey, where they are sympatric. P. daurica is considered to be a good species, which ranges from Croatia to Iran through Turkey and the Caucasus, and comprises six subspecies.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 1–11.  相似文献   

16.
Fossil mandibles of the Bornean shrew Crocidura foetida recovered from excavations at the west mouth of Niah cave, Sarawak, Malaysia, show that the late Pleistocene population at this lowland location was comparable in size with the large subspecies Crocidura foetida doriae , presently occurring at inland, upland locations. Two Holocene specimens fall in the size range of the smaller lowland subspecies C. f. foetida . Comparable post-Pleistocene size-reduction is known among other mammals of Borneo, but this is the first instance of dated examples. The evolutionary trend conforms with Bergmann's 'rule' but, other than climate change, no selective agent is apparent.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 413–419.  相似文献   

17.
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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