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1.
The endemic South African velvet worm genus Peripatopsis currently contains eight recognized species described from variable morphological characters and the current taxonomy is unsatisfactory. In an attempt to investigate evolutionary relationships within Peripatopsis, we collected 137 individuals from 34 sample localities for six of the eight species. Sequence data derived from two partial mitochondrial (mt)DNA gene loci (COI and 12S rRNA), as well as partial sequence data from the ribosomal nuclear 18S rDNA locus in combination with gross morphological characters and scanning electron microscopy (SEM), was used to examine evolutionary relationships. Phylogenetic relationships were investigated using minimum evolution (ME) and Bayesian inferences (BI). Additionally, we also undertook a maximum likelihood (ML) analyses on the combined DNA sequence data set. The combined DNA evidence topologies derived from the ME, BI, and ML was highly congruent and was characterized by the presence of multiple lineages within recognized taxa. Peripatopsis clavigera, Peripatopsis moseleyi, and Peripatopsis sedgwicki each comprised two evolutionary lineages; Peripatopsis capensis comprised three; and Peripatopsis balfouri comprised six operational taxonomic units respectively. Genealogical exclusivity at both mtDNA and nuclear DNA among the geographically coherent groups coupled with pronounced sequence divergence suggested a two‐fold increase in the number of species within Peripatopsis. Previously used gross morphological characters (such as the number of leg pairs and colour) were either highly variable within operational taxonomic units, or were invariant, suggesting that alternative morphological characters are necessary for species discrimination. SEM results revealed potentially useful diagnostic characters that can discriminate between at least discriminate some of the newly‐identified lineages. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society 2009, 97 , 200–216.  相似文献   

2.
Pulsatilla has been separated from Anemone by many authors. However, molecular phylogenies show that this genus, along with Barneoudia, Knowltonia, Hepatica and Oreithales, is nested with Anemone. For this reason, Pulsatilla is better treated as a section of Anemone. For the Chinese Pulsatilla species, nine species names are already available in Anemone, and the remaining names of three species and four infraspecific taxa are transferred to Anemone here.  相似文献   

3.
Leaf morphology and anatomy of Camellia section Camellia (Theaceae)   总被引:1,自引:0,他引:1  
The delimitations of species in Camellia section Camellia have been disputed for many years, resulting from uncertain relationships among species. Leaf morphological and anatomical characters for 54 species and three varieties in this section were investigated to reveal the relationships. Principal component analysis and cluster analysis were conducted using the transformed data for quantitative and qualitative characters from leaf morphology and anatomy. Combining the results of statistical analysis with comparative leaf characters of morphology and anatomy, we discussed the taxonomic treatment of section Camellia by Chang compared with that of Ming and we conclude that section Camellia consists of c. 50 species. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 456–476.  相似文献   

4.
Metalasia is a genus in tribe Gnaphalieae (Asteraceae), endemic to South Africa and with its main distribution in the Cape Floristic Region. The genus comprises 57 species and, with a number of closely related genera, it constitutes the ‘Metalasia clade’. A species‐level phylogenetic analysis is presented, based on DNA sequences from two nuclear (internal and external transcribed spacer: ITS, ETS) and two plastid (psbA‐trnH, trnL‐trnF) regions together with morphological data. Analyses combining molecular and morphological data attempt not only to resolve species interrelationships, but also to detect patterns in character evolution. Phylogenetic analyses corroborate our earlier study and demonstrate that Metalasia is formed of two equally sized, well‐supported sister groups, one of which is characterized by papillose cypselas. The results differ greatly from earlier hypotheses based on morphology alone, as few morphological characters support the phylogenetic patterns obtained. The two clades of Metalasia do, however, appear to differ in distribution, corresponding to the different rainfall regimes of South Africa. Analyses show a few taxa to be problematic; one example is the widely distributed M. densa which appears to be an intricate species complex. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174 , 173–198.  相似文献   

5.
Leaf surface morphology was analysed in 32 species representing the maculate species complex (the poorly resolved section Pictae) in the genus Aloe (Xanthorrhoeaceae). Few comparative morphological data are available for the complex. Leaf surface and stomatal characters observed by scanning electron microscopy show taxonomically significant interspecific variation. Most species are characterized by irregularly outlined, four‐ to six‐sided epidermal cells, the periclinal walls of which are flat and embellished with micropapillae and the anticlinal walls of which are indicated by channels on the leaf surface. The outer stomatal pore is typically sunken or plane and surrounded by four lobes on the leaf surface that may overarch the epistomatal chamber. The guard cells have distinct outer and inner stomatal ledges. Two geographical groups, comprising southern and east African species, are distinguishable by their leaf surface morphology. These characters are diagnostic in A. ellenbeckii, A. prinslooi and A. suffulta and support changes in the delimitation of A. greatheadii, A. macrocarpa and A. swynnertonii. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 418–428.  相似文献   

6.
7.
Chloroplast DNA cleavage sites for 10 restriction enzymes were mapped for 46 species representing all sections of Anemone, four closely related genera (Clematis, Pulsatilla, Hepatica, and Knowltonia), and three more distantly related outgroups (Caltha, Ranunculus, and Adonis). Comparison of the maps revealed that the chloroplast genomes of Anemone and related genera have sustained an unusual number and variety of rearrangements. A single inversion of a 42-kb segment was found in the large single-copy region of Adonis aestivalis. Two types of rearrangements were found in the chloroplast genome of Clematis, Anemone, Pulsatilla, Hepatica, and Knowltonia: An approximately 4-kb expansion of the inverted repeat and four inversions within the large single-copy region. These rearrangements support the monophyletic status of these genera, clearly separating them from Caltha, Ranunculus, and Adonis. Two further inversions were found in two Clematis species and three Anemone species. While appearing to support a monophyletic grouping for these taxa, these two inversions conflict with data from both chloroplast restriction sites and morphology and are better interpreted as having occurred twice independently. These are the first two documented cases of homoplastic inversions in chloroplast DNA. Finally, the second intron of the chloroplast rps12 gene was shown to have been lost in the common ancestor of the same three Anemone species that feature the two homoplastic inversions.  相似文献   

8.
9.
The genus Vanda and its affiliated taxa are a diverse group of horticulturally important species of orchids occurring mainly in South‐East Asia, for which generic limits are poorly defined. Here, we present a molecular study using sequence data from three plastid DNA regions. It is shown that Vanda s.l. forms a clade containing approximately 73 species, including the previously accepted genera Ascocentrum, Euanthe, Christensonia, Neofinetia and Trudelia, and the species Aerides flabellata. Resolution of the phylogenetic relationships of species in Vanda s.l. is relatively poor, but existing morphological classifications for Vanda are incongruent with the results produced. Some novel species relationships are revealed, and a new morphological sectional classification is proposed based on support for these groupings and corresponding morphological characters shared by taxa and their geographical distributions. The putative occurrence of multiple pollination syndromes in this group of taxa, combined with complex biogeographical history of the South‐East Asian region, is discussed in the context of these results. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 549–572.  相似文献   

10.
Doryopteris adornata is described as a new species from west‐central South America (Brazil, Bolivia, Paraguay, and Argentina). The dense indument of scales on the abaxial surface of the lamina is the most prominent diagnostic feature of this new species. Illustrations of the diagnostic characters are provided, as well as a table comparing the morphological characters of D. adornata with those of the two most similar species. The ecology and distribution are described. The conservation status for the new species using World Conservation Union (IUCN) guidelines/criteria is recommended. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 73–77.  相似文献   

11.
Only a few species belonging to the Proseriata (Platyhelminthes) show a parenchymatic pigmentation, which may aid identification. Among these, Pseudomonocelis agilis has a yellowish body and is provided with a reddish–brown girdle in front of the statocyst. The species is known for limited areas of northern Europe and the Mediterranean. The present study was conducted to assess both the taxonomic status of populations attributed to the species across the unusually wide range for an interstitial flatworm, which lacks an obvious means of dispersal, and the levels of genetic variability within and among populations, by employing an integrative approach that included the analyses, on six populations, of three molecular markers (small subunit ribosomal 18S‐like gene, inter‐simple sequence repeat, allozymes), karyotypes, and 11 morphological characters. Furthermore, crossbreeding experiments were carried out on the Mediterranean populations. The results obtained revealed the existence of four highly divergent genotypic clusters, accompanied by karyological differences, with complete intersterility among the clusters tested. The combination of approaches adopted strongly supports the conclusion that the wide‐ranging European pigmented species P. agilis is actually composed of four species: P. agilis in the Baltic area; Pseudomonocelis cetinae in the Adriatic; and Pseudomonocelis sp. nov. A and Pseudomonocelis sp. nov. B in the western and eastern Mediterranean, respectively. The latter two species are morphologically indistinguishable for the parameters essayed. Reconstruction of the phylogenetic relationships of these taxa, including congeneric and consubfamilial outgroups, showed that pigmentation is a plesiomorphic condition for the genus Pseudomonocelis and that Pseudomonocelis sp. nov. A shares a previously undetected, sister‐group relationship with species of the unpigmented P. ophiocephala complex. The present study thus depicts complex speciation processes in a mesopsammic species, which involves allopatric divergence operating on different scales and ecological shifts, and highlights that the contribution of microturbellarians to marine biodiversity may be seriously underestimated. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98 , 907–922.  相似文献   

12.
Relationships among the roughly 55 species of Iris subgenus Scorpiris have been studied. A matrix of six plastid DNA regions (matK, rpl14‐rps8 spacer, infArpl36 spacer, trnEtrnT spacer, trnL intron and trnL‐F spacer) was produced from 57 accessions (52 taxa) and analysed with both parsimony and Bayesian methods. Five major clades are identified, of which four have strong geographical correlations, whereas the fifth corresponds to Iris section Physocaulon. In our results, several species are placed with species not previously considered to be related, although, in some cases, there are morphological characters that suggest that these newly indicated relationships are reasonable. For some of the other oddly grouped species, we can only assume that remarkable parallelisms in morphology have occurred or hybridization is involved. Presently, with plastid DNA as our only comprehensive data resource, we are not able to evaluate more thoroughly these more puzzling associations of species. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167 , 281–300.  相似文献   

13.
The taxonomic status of Primula ranunculoides and other members of section Ranunuculoides is reappraised here based on data from morphological, reproductive and molecular characters. Multivariate analysis of morphological characters indicates that P. ranunculoides is a coherent species that can be distinguished from its sectional congeners P. cicutariifolia and P. merrilliana by the characters of simple kidney‐shaped outer leaves and the unique clonal reproductive ability by which apices of the scape differentiate into bulblets at the late phases of flowering. Recognition of P. ranunculoides at the specific level is also supported by palynological characters, breeding system, cross pollination results and molecular phylogenetic analysis of nrDNA internal transcribed spacer sequences. A taxonomic revision of section Ranunuculoides is presented and a possible mechanism of speciation discussed. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169 , 338–349.  相似文献   

14.
We tested the hypothesis of species taxonomy in the genus Gnopharmia (Macariini, Ennominae) that was recently established in a review based on discrete morphological characters. For this objective we integrated both DNA‐based and morphometric approaches in order to infer species boundaries. A 658‐bp fragment of the mitochondrial cytochrome c oxidase subunit 1 (CO1) (DNA barcode) was analysed from populations of five species distributed throughout the Middle East to assess their consistency with traditionally defined morphospecies. Signals in the morphological variation of the aedeagus of all relevant populations were evaluated using geometric landmarks. Consistent groupings compatible with the current taxonomic classification were found with both approaches. The results strongly support the distinction of seven closely related species. © 2013 The Linnean Society of London  相似文献   

15.
 Using two molecular data sets, the plastid atpB-rbcL intergenic spacer region and the nuclear ribosomal internal transcribed spacer regions (ITS), the taxonomic affinities of two newly available Anemone species from the Southern Hemisphere were tested. From previous work based on morphology and geographic distribution, it was assumed that A. tenuicaulis from New Zealand was most closely related to the Tasmanian A. crassifolia, whereas the affinity of A. antucensis from Chile and Argentina was regarded as uncertain. Analyses of molecular sequence data from these and 18 other species of Anemone s.lat. (with Clematis as outgroup) result in trees largely congruent with past analyses based on morphology and plastid restriction site data. They strongly support A. richardsonii and A. canadensis (with boreal distributions in the Northern Hemisphere) as paraphyletic to a well supported Southern Hemisphere clade consisting of A. antucensis and A. tenuicaulis. This group of four species is part of an otherwise predominantly Northern Hemisphere assemblage (subgenus Anemonidium s.lat., chromosome base number x=7), including A. narcissiflora, A. obtusiloba, A. keiskeana and A. (=Hepatica) americana. All other austral species included in the present sampling, A. crassifolia (Tasmania), A. knowltonia (=Knowltonia capensis), and A. caffra (both South African), form a separate clade, sister to A. (=Pulsatilla) occidentalis and other Northern Hemisphere anemones (subgenus Anemone s.lat., x=8). Possible phytogeographical links of the Southern Hemisphere species are discussed. Received April 23, 2001 Accepted October 4, 2001  相似文献   

16.
The family Galatheidae is among the most diverse families of anomuran decapod crustaceans, and the South‐West Pacific is a biodiversity hot spot for these squat lobsters. Attempts to clarify the taxonomic and evolutionary relationships of the Galatheidae on the basis of morphological and molecular data have revealed the existence of several cryptic species, differentiated only by subtle morphological characters. Despite these efforts, however, relationships among genera are poorly understood, and the family is in need of a detailed systematic review. In this study, we assess material collected in different surveys conducted in the Solomon Islands, as well as comparative material from the Fiji Islands, by examining both the morphology of the specimens and two mitochondrial markers (cytochrome oxidase subunit I, COI, and 16S rRNA). These two sources of data revealed the existence of eight new species of squat lobster, four of which were ascribed to the genus Munida, two to the genus Paramunida, one to the genus Plesionida, and the last species was ascribed to the genus Agononida. These eight species are described along with phylogenetic relationships at the genus level. Our findings support the taxonomic status of the new species, yet the phylogenetic relationships are not yet fully resolved. Further molecular analysis of a larger data set of species, and more conserved genes, will help clarify the systematics of this group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 465–493.  相似文献   

17.
The floral development of two Clematis species and four Anemone species (including Pulsatilla) (Anemoneae, Ranunculaceae) is described. Shared features are: (1) sepals shortly after initiation broad, crescent‐shaped, as opposed to the other organs, which are narrow and hemispherical; (2) outermost organs of the androecium often smaller than the others and sometimes sterile; (3) carpels ascidiate, with distinctive stalk, stigma papillate, decurrent; the carpels have one median fertile ovule and a few lateral sterile ovules in all species studied; the fertile ovule appears before the carpel closes. Generic differences are: (1) In Clematis, four sepals are initiated in two pairs; sometimes one of the sepals in the second pair appears to be divided into two organs (double position) resulting in a pentamerous perianth; the first eight stamens are positioned in two alternating whorls, the outer whorl alternating with the four sepals. In Anemone, the perianth organs, if five, are initiated in spiral sequence; in the Pulsatilla group of Anemone, six sepals are initiated in two whorls; the first three organs of the androecium (staminodes) alternate with the inner sepals. (2) Further androecial organs are mostly in complex whorls (i.e. including double positions) in Clematis, but in an irregular spiral or in irregular complex whorls in Anemone. (3) Anther maturation is largely centripetal in Clematis, but centrifugal or bidirectional in Anemone. In Clematis macropetala, the outermost organs of the androecium lack anthers and the filaments expand and become petal‐like. In contrast, in the Pulsatilla group of Anemone, these organs retain sterile anthers and become small, capitate organs. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 162 , 77–100.  相似文献   

18.
Linaria incarnata has been treated as a widely distributed Ibero‐North African species in the latest taxonomic reviews. Morphological and phylogenetic disparity between populations of this species has been previously reported. Here we present new morphological and phylogenetic evidence for the disintegration of L. incarnata into three distinct species: L. incarnata from the western Iberian Peninsula; L . mamorensis sp. nov. from north‐western Morocco; and L. onubensis from south‐western Spain. The relatively poor morphological differentiation between these taxa (which can be regarded as cryptic species) and their distinct phylogenetic positions indicate that characters of the L. incarnata morphotype have been acquired multiple times in the evolution of Linaria section Versicolores. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 00, 000–000.  相似文献   

19.
With c. 85 species, the genus Micranthes is among the larger genera of the Saxifragaceae. It is only distantly related to the morphologically similar genus Saxifraga, in which it has frequently been included as Saxifraga section Micranthes. To study the molecular evolution of Micranthes, we analysed nuclear ribosomal (internal transcribed spacer, ITS) and plastid (trnLtrnF) DNA sequences in a comprehensive set of taxa comprising c. 75% of the species. The molecular phylogenetic tree from the combined dataset revealed eight well‐supported clades of Micranthes. These clades agree in part with previously acknowledged subsections or series of Saxifraga section Micranthes. As these eight groups can also be delineated morphologically, we suggest that they should be recognized as sections of Micranthes. New relationships were also detected for some species and species groups, e.g. section Davuricae sister to sections Intermediae and Merkianae, and M. micranthidifolia as a member of section Micranthes. Species proposed to be excluded from the genus Micranthes for morphological reasons were resolved in the molecular tree in Saxifraga. Many morphological characters surveyed were homoplasious to varying extents. Micromorphological characters support comparatively well the clades in the phylogenetic tree. An updated nomenclature and a taxonomic conspectus of sections and species of Micranthes are provided. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178 , 47–66.  相似文献   

20.
Integrative taxonomy is considered a reliable taxonomic approach of closely related and cryptic species by integrating different sources of taxonomic data (genetic, ecological, and morphological characters). In order to infer the boundaries of seven species of the evacanthine leafhopper genus Bundera Distant, 1908 (Hemiptera: Cicadellidae), an integrated analysis based on morphology, mitochondrial DNA, and hyperspectral reflectance profiling (37 spectral bands from 411–870 nm) was conducted. Despite their morphological similarities, the genetic distances of the cytochrome c oxidase subunit I (COI) gene among the tested species are relatively large (5.8–17.3%). The species‐specific divergence of five morphologically similar species (Bundera pellucida and Bundera spp. 1–4) was revealed in mitochondrial DNA data and reflectance profiling. A key to identifying males is provided, and their morphological characters are described. Average reflectance profiles from the dorsal side of specimens were classified based on linear discriminant analysis. Cross‐validation of reflectance‐based classification revealed that the seven species could be distinguished with 91.3% classification accuracy. This study verified the feasibility of using hyperspectral imaging data in insect classification, and our work provides a good example of using integrative taxonomy in studies of closely related and cryptic species. © 2015 The Linnean Society of London  相似文献   

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