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A total of nine enzymes coded by 14 loci were assayed for each of six populations (from the north-eastern Atlantic and the Mediterranean) of two sea bream subspecies ( Diplodus sargus sargus and Diplodus sargus cadenati ). Diagnostic alleles were observed for each subspecies, although there were several common alleles. Estimates of variance in allele frequencies among samples ( F ST) revealed significant differences ( P  < 0.05) among both subspecies. Genetic divergence was found between Atlantic and Mediterranean samples: values for genetic distances were higher than 0.163. Furthermore, D. sargus cadenati populations displayed a higher mean weight and length than D. sargus sargus populations and significant differences in growth were found among subspecies and populations. These results are discussed in terms of levels of gene flow and its respective relationships with water circulation in the Strait of Gibraltar and geological events.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 705–717.  相似文献   

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Miniopterus schreibersii is a polytypic bat species, with one of the widest distribution ranges among the mammals. We studied the genetic differentiation and taxonomy of this species in the transition zone between south-eastern Europe and Anatolia (in Asia), where two subspecies have been described. The results indicated a sharp genetic break between the samples from western Anatolia and south-eastern Europe and those of eastern Anatolia. In addition, the samples from western Anatolia and south-eastern Europe were seen to be reciprocally monophyletic, although the differentiation was less drastic. These patterns of genetic differentiation suggest the presence of two distinct groups within the M. schreibersii complex in the region, concordant with previous subspecific recognition. The cause of this genetic break is most likely differentiation in separate glacial refugia followed by secondary contact. However, more samples are needed to assess whether these represent different species, as well as to understand more clearly the causes of this differentiation.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 577–582.  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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Chromosome numbers and measurements were recorded in 47 individuals of ten taxa of Primula , representing eight species and two subspecies from ten populations. The basic numbers of chromosomes were x  = 8, 9 or 11, and they were mostly metacentric, medium-long to medium-small, ranging in length from c . 3.6 µm to 1.6 µm. Diploid chromosome numbers of 2 n  = 2 x  = 24 and 22 were scored for the first time in P. loeseneri Kitag. and P. prenantha Balf. & Sm., respectively. A new ploidy level of 2 n  = 4 x  = 44 was found in P. burmanica Balf. & King. The recorded diploid numbers of the remaining species confirmed earlier reports. Interspecific variability in chromosome numbers was correlated with heterogeneity in their mean length. Comparison of the data with those in the literature revealed that the observed variability of chromosomal characters was compatible with the other taxonomic criteria and supports the current taxonomic delimitation. Chromosomal variation at the diploid level is the predominant feature in Primula evolution, and allopatric speciation has played a major role in its specific diversity. Subgen. Aleuritia could represent the main clade from which the other subgenera have evolved. The origin of the chromosome numbers, geographical distribution and evolution of the species were assessed, and the parallel polyphyletic mode of evolution in the genus was confirmed.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 211–219.  相似文献   

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A distinctive new species of dwarf monocaulous Coffea (Rubiaceae) from Cameroon is described and illustrated. Coffea mapiana is the second dwarf monocaulous known from Cameroon. Its diagnostic characters are elucidated and its taxonomic affinities are discussed; a conservation assessment is provided.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 425–430.  相似文献   

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Population divergence can be detected by the divergence of functional and neutral characters. Under some circumstances, it is desirable to have available a character that is discretely expressed in either of the diverging genomes, rather than the evaluation of qualitative variation of continuous characters. In the present study, we investigated mass peaks of peptide hormones in a model system of population divergence, the hybrid zone of two Chorthippus parallelus subspecies in the French–Spanish Pyrenees. Mass spectra from neuroendocrine tissues have previously been identified as species-specific and may have a sufficient resolution to vary at the subspecies level. For the first time, we succeeded in the detection of a subspecies-specific expression of neuropeptides collected from single individuals. Mass spectra sampled from populations across the C. parallelus grasshopper hybrid zone indicated neuropeptide identity between the sexes and within sample sites. The distribution of a single distinct but variable peptide signal, however, very closely followed the cline of the hybrid zone as derived from the mean variation in several continuous characters. The identity of this peptide in populations from the northern Pyrenees and central Europe supports a neuropeptide differentiation of preglacial origin. The observed differentiation in the peptide profile of the two subspecies demonstrates that a peptidomic approach may be a promising perspective to reconstruct reproductive isolation in an insect hybrid zone.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 541–548.  相似文献   

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Historically, morphological variation has been used to classify many species (and subspecies) of Lepidoptera. However, some of this variation may be unsuitable for inferring the recent evolutionary history of populations. Genetic data provide an alternative. We examine the morphological and genetic variation within and between British subspecies of Coenonympha tullia (Müller 1764) to test the hypothesis that neutral genetic variation corresponds to morphological variation. We find that most morphological and genetic variation occurs within populations and that those populations designated as subspecies based on morphological characters are not necessarily most closely related for mitochondrial DNA or nuclear DNA (amplified fragment length polymorphisms and allozymes). Thus, the notion that wing spot variation reflects population isolation and therefore genetic differentiation does not hold. The present study highlights the need for genetic data where taxonomy may be based on environmentally plastic or locally adapted characters because such characters will not reflect the true population genetic history.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 314–327.  相似文献   

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Few operational methods exist for delimiting species boundaries, and these usually require sampling strategies that are unrealistic for widespread organisms that occur at low densities. Here we apply molecular, morphological and ecological species delimitation criteria to a wide-ranging, fragmented group of Asian green pitvipers, the Popeia popeiorum complex. A mitochondrial DNA phylogeny for the group indicates two well-differentiated clades, corresponding mainly to northern and southern parts of its range. Strong phylogeographical structure within each clade suggests isolation in forest refugia during the Pliocene and a southward colonization of the Sunda islands during the Pleistocene. Multivariate analysis of morphological characters reveals a generally conserved pattern of geographical variation, incongruent with the recovered phylogenetic history. We compare groups delineated by mtDNA variation to morphological and ecological divisions in the complex, and discuss the implications of these for the taxonomy of the group. Discordance between species boundaries inferred from different criteria suggests that combining independent sources of data provides the most reliable estimation of species boundaries in organisms that are difficult to sample in large numbers.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 343–364.  相似文献   

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The taxonomic position of western Asian members of Gentiana sect. Pneumonanthe has long been a matter of conflict. In this paper, the six western Asian species currently recognized as belonging to sect. Pneumonanthe ( G. boissieri , G. calycina , G. freyniana , G. gelida , G. paradoxa , and G. septemfida ) are compared and their relationships established using a morphological phylogenetic analysis. Seed testa and flower and leaf morphological characters were studied and 11 characters were selected for a cladistic analysis. Euro-Siberian and Far Eastern taxa of sect. Pneumonanthe ( G. pneumonanthe and G. scabra ) were used as outgroups. Our results suggest the presence of two morphologically distinct clades within the western Asian gentians: a Septemfida and a Gelida clade. G. calycina and G. freyniana show close affinities to G. boissieri and G. gelida , and are distinct from G. septemfida s.l. Biogeographical aspects of the two groups are discussed.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 197–208.  相似文献   

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Because of the poor state of knowledge of many of the gymnophthalmid genera, systematic revision is necessary to render the classification consistent with evolutionary history. To that end, I conducted a review of the species of three genera of the Cercosaurinae which appear to form a monophyletic group: Cercosaura , Pantodactylus , and Prionodactylus . Phylogenetic analysis of 61 morphological characters was conducted after specimens of all species were examined to evaluate the composition of each taxon. The phylogenetic reconstruction suggested that the genus Prionodactylus was paraphyletic. A new phylogenetic classification is proposed that synonymizes Pantodactylus and Prionodactylus with Cercosaura. Cercosaura is redefined to include 11 species and seven subspecies. A key is provided to distinguish among species.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 137 , 101−115.  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   

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Although the integration of DNA information in taxonomy has been invaluable, logistical problems relating to sampling can seriously limit its applicability. Here we describe the analysis of a morphologically cryptic species complex, in which we maximize the information present by using both a DNA phylogeny and a multivariate morphometric approach. The green pitviper Trimeresurus stejnegeri s.l. is widespread in Asia, with a number of described subspecies (some of which are considered full species by some workers) and two new species that have recently been described from Thailand. The phylogeny indicates three clades, which can also be discerned in the principal component analyses of morphological variation. Combining molecular and morphological information permits evaluation of the taxonomic position of populations not represented in the phylogeny − in particular, the subspecies T. s. chenbihui and T. s. yunnanensis . We discuss nomenclatural issues raised by this analysis, although these cannot be fully resolved until the holotypes of these subspecies can be examined. Finally, we apply a molecular clock calibrated in New World pitvipers, and discuss some of the palaeoclimatic changes that might have impacted upon diversification in this group.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 82 , 219–235.  相似文献   

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We describe Centrolene bacatum , C. buckleyi , Cochranella posadae , and a new species of Cochranella from Yanayacu Biological Station on the Amazonian slopes of the Ecuadorian Andes. The new species differs from other species in Centrolenidae by a combination of characters, including reduced webbing between Fingers III and IV, and kidneys covered with white peritoneum. We summarize the current generic and infrageneric classification in Centrolenidae and discuss some of its problems. A phylogenetic analysis of morphological and behavioural data shows that the genera Centrolene and Cochranella might not be monophyletic; the genus Hyalinobatrachium and, in particular, the group H. fleischmanni seem to be monophyletic. However, an analysis with many more characters is needed to resolve the relationships of glass frogs.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 489–513.  相似文献   

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Noccaea camlikensis sp. nov. (Brassicaceae) is described and illustrated from a localized serpentine range in southern Turkey. Its close relationship to N. cariensis , from which it differs in leaf and carpological characters, is discussed. The protologue of this fairly unknown species can now be amended to cover better the morphological variability of this taxon. A comparative study of seed-coat anatomy advocates its move from Thlaspi to Noccaea ; the relevant combination N. cariensis (Carlström) Parolly, Nordt & Aytaç is made. The ecology of both vicarious species is discussed and their distribution mapped.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 409–416.  相似文献   

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