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1.
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   

2.
Cytology and taxonomy of Coptis teeta Wall.(Ranunculaceae)   总被引:1,自引:0,他引:1  
Cytological investigations of 13 natural populations of Coptis teeta indicated that the species has a somatic number of 18 chromosomes which form nine homomorphic pairs. The species did not possess any supernumerary chromosomes. The chromosome number, size and morphology were similar in all populationS. Based on the taxonomic studies the 13 natural populations are grouped into two well-defined subspecies, teeta and lohitensis, for which a key is provided.  相似文献   

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A morphological study, both in the field and from herbarium material, showed that there are no convincing characteristics separating the Turkish endemics Iris stenophylla ssp. stenophylla and ssp. allisonii . A cytological survey revealed chromosome numbers of 2 n  = 24, 26 and 26 + 1B. No variation in either chromosome number or karyotype was found in ssp. allisonii , which always had 2 n  = 26, although the chromosome number and karyotypes of ssp. stenophylla were variable. Since neither morphological nor cytological differences were sufficient to separate the two subspecies, I. stenophylla ssp. allisonii is therefore reduced to a synonym of I. stenophylla .  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 115−127.  相似文献   

5.
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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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   

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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   

10.
The high-ploid species Papaver dahlianum , P. lapponicum , P. laestadianum and P. radicatum were compared by means of enzyme electrophoresis. The diploid P. alpinum from the Alps and garden material of the assumed diploid P. croceum from Asia were also included. The results are compared with those of previous morphological and cytological investigations. Generally, only small differences were found among the species. The maintenance of 13 subspecies of P. radicatum as published from the Nordic area was not supported. The octoploid P. laestadianum was nearly identical to the decaploid P. radicatum and inclusion in P. radicatum is justified. The octoploid P. lapponicum was also very similar to P. radicatum and inclusion of it in the latter should be considered. The most distinct of the taxa was the decaploid P. dahlianum , and the maintenance of two subspecies, ssp. polare and ssp. dahlianum can be defended. A hybrid origin of P. radicatum (10x) from P. lapponicum (8x) and P. alpinum (2x), and of P. dahlianum (10x) from P. lapponicum and P. croceum (2x) has been proposed, but a more likely explanation might be that P. dahlianum , P. radicatum and P. lapponicum have all arisen by polyploidization from closely related diploids without hybridization.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 255−269.  相似文献   

11.
A re-evaluation of Minuartia graminifolia has been undertaken based on comparative morphological studies. M. graminifolia subsp. rosani (an endemic of the south-central Apennines and Sicily) and subsp. hungarica (an endemic of the Banat region of Romania) are accepted infraspecific taxa. M. graminifolia subsp. hungarica is lectotypified. M. graminifolia subsp. clandestina is confirmed for Italy; the taxon is neotypified. The type subspecies is considered an endemic to the east-central Alps. Keys to the species of Minuartia ser. Graminifoliae and to the subspecies of M. graminifolia are provided.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 419–432.  相似文献   

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Two subspecies of the grasshopper Chorthippus parallelus form a hybrid zone in the Pyrenees. Transitions across the zone, including changes in mating signals and reproductive isolation have been intensively studied. Cuticular pheromones have been identified as likely mate recognition signals. Since the major role of the cuticle is in waterproofing, environmental adaptation of cuticular composition has the interesting potential to generate assortative mating as an incidental by-product. We describe the pattern of variation in cuticular hydrocarbon blend in four transects through the hybrid zone. We find no evidence for a previously observed displaced cline in one blend component. There were differences between subspecies but these varied among transects and were small compared with variation between transects. We examined environmental variation within one transect and found a correlation between vegetation and cuticular composition, suggesting that environment influences the constitution of the cuticle, and hence natural selection may interact with mating signals in this species.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 78 , 193−201.  相似文献   

14.
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   

15.
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   

16.
The Deschampsia cespitosa complex in Russia is revised. Related taxa common to Russia and adjacent regions (i.e. northern Europe, Arctic America and Japan) are also considered. Deschampsia cespitosa s.l. is characterized by open to less commonly rather contracted panicles, spikelets (1) 2 (3)-flowered, 4-toothed lemmas with the lateral teeth larger, and awns straight or bent, inserted from the base to the top of the lemmas. Due to extensive overlapping in diagnostic characters, it is not possible to accept the specific status for D. borealis (Traut.) Roshev., D. brevifolia R.Br., D. macrothyrsa Tatew. et Ohwi and D. obensis Roshev; instead, they are treated as subspecies of D. cespitosa (L.) Beauv. Morphological differences are insufficient for a clear differentiation among subspecies, and geographical distributions also need to be considered. A total of 14 subspecies is accepted. Observations on ecology, problems of specific and subspecific delimitation, a distribution map, and considerations of evolution of the complex are provided. One new combination is made, Deschampsia cespitosa ssp. sukatschewii (Popl.) Chiapella & Prob.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 213–228.  相似文献   

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18.
Allozyme diversity was studied within and among populations of five related taxa of Antirrhinum L. endemic to the Iberian Peninsula ( A. graniticum Rothm. ssp. graniticum , ssp. brachycalyx Sutton and ssp. ambiguum (Lange) Mateu & Segarra, A. boissieri Rothm. and A. onubensis (Fdez. Casas) Fdez. Casas). All of the studied taxa are obligate outcrossing endemic perennial herbs which form isolated populations. However, the taxa vary in range and population sizes, and are found on different soil types. The level and distribution of allozyme diversity differed widely between taxa: A. graniticum ssp. brachycalyx had the lowest level of allozyme diversity (HT = 0.09), whilst the highest level was detected in A. boissieri (HT = 0.25). Total variation was partitioned into within- and among-population variation. The proportion attributable to variation within populations varied from about 67% up to 84.3% and 89.5% in A. graniticum ssp. brachycalyx and A. graniticum ssp. ambiguum , respectively. Both these subspecies also showed little population divergence (GST = 0.10 and 0.09, respectively) and had high levels of estimated gene flow (Nm = 2.18 and 2.62, respectively). These results are discussed in relation to geographical proximity of populations and habitat continuity. Isolation by distance was not detected in any of the studied taxa. This result suggests that divergence among populations is due to random genetic drift.  © 2003 The Linnean Society of London . Biological Journal of the Linnean Society , 2003, 79 , 299–307.  相似文献   

19.
Cytogenetic investigations of 13 natural populations of Coptis teeta , an endemic and endangered medicinal plant from the Eastern Himalaya, were carried out. About 70–80% individuals in some of the populations were synaptic mutants. The predominantly sexually breeding plant populations were confined to higher cooler latitudes, whereas the mutant apomict inhabited lower warmer latitudes. The breeding systems were observed to be associated with morphological differentiation and ecological preference of some populations. Individuals of subsp. teeta reproduced sexually as well as vegetatively, but those of subsp. lohitensis have adapted almost entirely to a vegetative mode of reproduction. Though no variation was observed in somatic chromosome number and karyotypes, the two subspecies differed significantly with respect to their male meiotic behaviour and rhizome morphology. The mutants either produced little fertile pollen or were completely sterile, leading to low seed production or none at all. This has resulted in low reproductive fitness, localized distribution and small population sizes of the taxon.  相似文献   

20.
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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