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1.
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   

2.
Abstract: Bennettites are an abundant and frequently well‐preserved component of many Mesozoic fossil floras, often playing an important ecological role in flood plain vegetation communities. During a recent study focusing on stomatal indices of Triassic–Jurassic fossil plants, it became evident that the leaf fragments of two bennettite genera Anomozamites Schimper (1870) emend. Harris (1969) and Pterophyllum Brongniart (1825) display a significant overlap of leaf shape as well as cuticular characters. Owing to the preference of recognition of single taxa (ideally species) for the stomatal method, we use a database of 70 leaf fragments of Anomozamites and Pterophyllum compressions from five isotaphonomic Late Triassic sedimentary beds of Astartekløft in East Greenland to test whether leaf and cuticle fragments of the two genera can be separated using a range of quantitative and qualitative morphological and statistical analyses. None of the observed characters – including stomatal frequencies – could be applied to separate the fragments of the two genera into well‐defined groups. Our results therefore indicate that fragmented material and dispersed cuticles cannot be utilized to distinguish between Anomozamites or Pterophyllum at the genus level, but that instead these cuticle fragments may be used interchangeably as stomatal proxies. Classification of fossil leaves into either of these genera is thus only possible given adequate preservation of macro‐morphology and is not possible based solely on cuticle morphology. We suggest that this large inter‐ and intra‐generic morphological variation in both leaf and cuticle traits within Anomozamites and Pterophyllum may be related to the bennettites’ role as understory plants, experiencing a range of micro‐environmental conditions, perhaps depending mainly on sun exposure. Based on the results obtained in this study, we conclude that Anomozamites and Pterophyllum cuticle fragments can be employed interchangeably in palaeo [CO2] reconstructions based on the stomatal method, thus potentially annexing a plethora of bennettitalean fossil plant material as CO2 proxies, including dispersed cuticles.  相似文献   

3.
Calophyllum (Calophyllaceae), previously placed in Clusiaceae, is easily recognizable by its opposite entire leaves with close parallel venation alternating with resin canals. However, distinction between species has been difficult, because of infraspecific variation in tepal and stamen number and resemblance among species that share similar habitats. Here, I report the results of multivariate analyses of morphological and anatomical characters for Calophyllum in South America, and provide a taxonomic treatment for the genus in South America, the first since that of Vesque in 1893. Thirteen preliminary morphogroups were identified. Thirty‐two morphological characters of the leaf, flower and fruit from 401 specimens, and 17 anatomical leaf characters from 45 specimens were measured and analysed using principal component analyses (PCAs) and discriminant analyses (DAs). PCAs were used to find groups and DAs were used to validate those PCAs that were potential groups. Two main subgroups were identified in the general analysis. Subgroup M1 has terete stems and smaller leaves and flowers than subgroup M2, which, instead, has quadrangular stems. Only subgroup M2 showed distinctive clusters in regional and local analyses. Distinctive clusters and morphological and anatomical characters helped us to recognize four species in South America, including a new species, Calophyllum pubescens sp. nov. . In addition, a new species, Calophyllum mesoamericanum sp. nov. , is described from Central America. © 2013 The Linnean Society of London,  相似文献   

4.
5.
Traditional treatments of Aster were found unsatisfactory in predicting cytological and morphological characteristics of members of various subgenera, sections and subsections of different authors. A realignment of species into these infrageneric categories is presented and is based on sets of shared morphological characteristics of roots or rhizomes, leaves, and phyllaries. Eight subgenera are recognised in Aster. Subgenus Aster is divided into five sections on morphological characteristics: three have X = 9, one has X = 8 and one has X = 7. Subgenus Aster section Dumosi has been redefined and contains all the X = 8 species. Ten X = 5 species and one X = 4 species previously classified in up to six sections of subgenus Aster were found to be morphologically and cytologically related to each other, but unrelated to the other species of Aster. These eleven species have been assigned to the genus Lasallea sensu Semple & Brouillet. Lasallea has been divided in sections and subsections with new combinations presented in this paper.  相似文献   

6.
Li WP  Yang FS  Jivkova T  Yin GS 《Annals of botany》2012,109(7):1341-1357

Background and Aims

The classification and phylogeny of Eurasian (EA) Aster (Asterinae, Astereae, Asteraceae) remain poorly resolved. Some taxonomists adopt a broad definition of EA Aster, whereas others favour a narrow generic concept. The present study aims to delimit EA Aster sensu stricto (s.s.), elucidate the phylogenetic relationships of EA Aster s.s. and segregate genera.

Methods

The internal and external transcribed spacers of nuclear ribosomal DNA and the plastid DNA trnL-F region were used to reconstruct the phylogeny of EA Aster through maximum parsimony and Bayesian analyses.

Key Results

The analyses strongly support an Aster clade including the genera Sheareria, Rhynchospermum, Kalimeris (excluding Kalimeris longipetiolata), Heteropappus, Miyamayomena, Turczaninowia, Rhinactinidia, eastern Asian Doellingeria, Asterothamnus and Arctogeron. Many well-recognized species of Chinese Aster s.s. lie outside of the Aster clade.

Conclusions

The results reveal that EA Aster s.s. is both paraphyletic and polyphyletic. Sheareria, Rhynchospermum, Kalimeris (excluding K. longipetiolata), Heteropappus, Miyamayomena, Turczaninowia, Rhinactinidia, eastern Asian Doellingeria, Asterothamnus and Arctogeron should be included in Aster, whereas many species of Chinese Aster s.s. should be excluded. The recircumscribed Aster should be divided into two subgenera and nine sections. Kalimeris longipetiolata, Aster batangensis, A. ser. Albescentes, A. series Hersileoides, a two-species group composed of A. senecioides and A. fuscescens, and a six-species group including A. asteroides, should be elevated to generic level. With the Aster clade, they belong to the Australasian lineages. The generic status of Callistephus should be maintained. Whether Galatella (including Crinitina) and Tripolium should remain as genera or be merged into a single genus remains to be determined. In addition, the taxonomic status of A. auriculatus and the A. pycnophyllus–A. panduratus clade remains unresolved, and the systematic position of some segregates of EA Aster requires further study.  相似文献   

7.
瑞香属和荛花属为瑞香科瑞香亚科的落叶或常绿灌木,中国西南部是瑞香属和荛花属的重要分化中心。全世界共有瑞香属95种、荛花属70种,中国分布有瑞香属52种、荛花属49种。瑞香属和荛花属的分类学研究一直存在不同程度的分歧。花盘形状和果实类型在传统分类中一直是区分瑞香属和荛花属的典型特征,而花盘形态和果实类型在2个属中存在交叉和过渡,部分植物分类学家根据这些特征将两个属进行过不同程度的归并。该研究采用数量分类法对瑞香属77种(变种)和荛花属62种(变种)植物,选取32个形态学性状进行聚类分析和主成分分析。结果表明:聚类分析和主成分分析均显示两属均未形成单系类群。在主成分分析中,前3个主成分分析的贡献值为35.56%,传统分类中用来区分两属的花盘形状、叶序及果实类型等特征对前3个主成分贡献相对较小,因此,传统分类学中对这两个属进行区分的性状并没有典型的分类学意义。同时,聚类图和主成分分析得到的散点图均不能将这两个属区分开来。数量分类研究结果显示两属植物存在明显的交叉,支持瑞香属和荛花属不是两个独立自然类群的观点。  相似文献   

8.
Phylogenetic analyses were conducted to determine the relationships between and characterize the morphological variation among three genera of Anacardiaceae:Bonetiella, Pseudosmodingium, andSmodingium. The first two genera are endemic to Mexico and the third to South Africa.Bonetiella andSmodingium are monotypic.Pseudosmodingium has eight species, six extant and two fossil, and all were included in the analyses. Fifty-six anatomical characters for leaves, wood, and fruit, as well as morphological characters, were considered. Our results indicate thatSmodingium is not closely related toPseudosmodingium andBonetiella, and that these last two genera are sister taxa.Pseudosmodingium is a monophyletic group and the two fossil species are related to species from the same geographical area of central Mexico where they were found. Fruit anatomical characters were significant at the generic level, while leaf anatomical characters were important at the species level inPseudosmodingium.
Resumen  En este trabajo se llevaron a cabo análisis filogenéticos para determinar las relaciones filogenéticas así como caracterizar la variación morfológica de tres géneros de Anacardiaceae:Bonetiella, Pseudosmodingium ySmodingium. Los dos primeros son endémicos a México y el terceroo a Sudáfrica.Bonetiella ySmodingium son monotípicos.Pseudosmodingium incluye ocho especies, dos fósiles y el resto vivientes, y todas fueron consideradas en los análisis. Se consideraron 56 caracteres tanto anatómicos como morfológicos de hojas, madera y frutos. Nuestros resultados indican queSmodingium no está cercanamente relacionado aPseudosmodingium yBonetiella, y que estos dos últimos géneros son taxa hermanos.Pseudosmodingium es un grupo monofilético y las dos especies fósiles están relacionadas a especies que crecen en las mismas áreas geográficas del centro de México, donde fueron descubiertas. Los caracteres anatómicos del fruto fueron significativos a nivel genérico, mientras que los de hoja fueron importantes a nivel de especies enPseudosmodingium.
  相似文献   

9.
Alstroemerieae is an exclusively Central and South American tribe belonging to Alstroemeriaceae, which comprises two large genera, Alstroemeria and Bomarea. Alstroemeria has two areas of distribution, mediterranean Chile and central southeastern Brazil. Most Bomarea species grow in forests and hedges in moist areas, however, some species are adapted to dry Andean valleys and high altitudes. Previous leaf anatomical data were obtained from a limited group of species. To assess the value of the anatomical characters for the systematics and their importance as adaptations to different environments, we compared representative species from different geographical areas and habitats. Data regarding leaf anatomy and micromorphology were obtained from light microscopy and scanning electron microscopy and were combined with macromorphology for 27 Alstroemerieae species. In accordance with earlier studies, our results show variation in relation to several leaf morpho‐anatomical characters. Based on these we define seven types. We furthermore analyzed the morpho‐anatomical characters in a phylogenetic context. Morpho‐anatomical characters are highly homoplastic within the family. Leaf anatomy may support monophyly of Baker's informal grouping of Alstroemeria Brazilian species with rigid leaves, however, a more thorough study of Brazilian Alstroemeria species are needed to confirm this.  相似文献   

10.
11.
Previous taxonomic assessments of the hydrophytic genus Nuphar Sm. (Nymphaeaceae) have inadequately considered the range of morphological variation existing in the genus. A comprehensive statistical analysis of morphological features among the recognized taxa of Nuphar is presented here, first using 10 fruit characters to delimit the separation of two infrageneric groups of taxa, and secondly using 31 characters to quantify the morphological variation found within sect. Nuphar. Results from combined phenetic analyses provided empirical support for recognition of two infrageneric groups of species in the genus (largely by fruit, stigmatic disk margin, neck, and stigmatic disk size) and for separation of taxa within sect. Nuphar (by leaf size, and fruit disk and neck size). Statistical analyses demonstrate that extensive variation in ranges of character states exists among sect. Nuphar taxa. However, a suite of qualitative and quantitative characters can be used to recognize five species and three subspecies within this predominantly Old World assemblage.  相似文献   

12.
Relationships of the eight species of the liverwort genus Radula occurring in Portugal (mainland, the Madeira and Azores archipelagos), including the Macaronesian endemics R. jonesii and R. wichurae, were evaluated based on molecular, phytochemical and morphological–anatomical data. Maximum parsimony and Bayesian analyses were performed with sequences from three plastid DNA markers (trnS GGA-rps4 spacer, rps4 gene, trnL UAA intron), volatile oil compounds, as well as qualitative morphological–anatomical characters. In addition, the molecular data were subjected to maximum likelihood analysis. The eight taxa, R. aquilegia, R. carringtonii, R. complanata, R. holtii, R. jonesii, R. lindenbergiana, R. nudicaulis and R. wichurae, can be clearly distinguished from each other, either by molecular data alone or by combination of characters from all three data sets. Radula aquilegia is monophyletic according to the molecular data, but shows considerable, yet undescribed intraspecific morphological and phytochemical variability. Recognition of R. complanata and R. lindenbergiana as separate species, previously based solely on the paroecious vs. dioecious sexual condition, is moderately supported by the molecular phylogenetic analyses and strongly supported by the phytochemical data. The Radula species, narrowly distributed in Macaronesia and Atlantic Europe, probably have two different origins. For Radula holtii and R. nudicaulis, connections with Radula species from the Neotropics are indicated. The other species, among them the two Macaronesian endemics, are closely related with the R. complanata/R. lindenbergiana complex, which is widely distributed in the northern hemisphere.  相似文献   

13.
Cassia L. sensu lato, a large heterogeneous genus of flowering plants, occurs naturally in the tropics around the world. Recent works based on floral morphology have supported a division of this genus into three genera, namely Cassia L. s. str., Chamaecrista Moench and Senna Mill. In order to investigate this new classification, 508 specimens of 18 taxa of the genus Cassia s.l. grown in Thailand were analyzed using cluster analysis and canonical discriminant analysis. The total 32 vegetative and reproductive morphological characters were employed in these analyses. In cluster analysis, Cassia s.l. can be separated into four groups, respectively viz. Chamaecrista, Senna alata, Senna and Cassia s /str. The four-cluster grouping is discussed. From a canonical discriminant analysis using the four-cluster grouping as a priori groups, it can be concluded that Cassia s. str., Senna, and Chamaecrista are indeed distinct taxa. The three most important characters that separate the three genera are filament length, fruit length, and ovary stalk length. These quantitative characters, together with some qualitative characters, were useful in constructing an identification key to these genera. Among the three genera, it was also found that Senna is rather a heterogeneous taxon. The difference between the studied species was discussed.  相似文献   

14.
Schisandraceae are traditionally subdivided in two genera, Schisandra and Kadsura, based on differences in the organisation of the floral receptacle, the carpels, and the presence or absence of a ``pseudostigma'. Recently, phylogenetic analyses utilizing ITS sequence data and morphological data resulted in incongruent tree topologies, with the morphological trees suggesting monophyly of the two genera, whereas ITS trees did not resolve Schisandra and Kadsura as monophyletic clades. In the present paper we study seed morphology and leaf epidermal features of 22 species of Schisandraceae in order to provide additional data for a morphological data matrix. Seed morphological characters are highly homoplastic and do not yield further evidence for monophyly of the two genera. Instead, a number of characters appear to support sister group relationships between taxa within the genera, such as, for instance, for K. coccinea and K. scandens, both of which have large seeds along with a multi-layered mesotesta. Considering leaf epidermal characteristics, species of Kadsura were found to be consistently amphistomatic, whereas species of Schisandra are always hypostomatic. Phylogenetic analysis using the extended data matrix resulted in weakly supported Kadsura and Schisandra clades with five and four synapomorphies indicating monophyly of Kadsura and Schisandra, respectively. Fossils ascribed to Schisandraceae date back to the Late Cretaceous. These are tri-and hexacolpate pollen types displaying a combination of features found in modern Schisandraceae and partly also in Illiciaceae. Leaf remains from this period are poorly preserved and difficult to ascribe to Schisandraceae because of the lack of synapomorphies for the family. In the Early Cainozoic, leaf and seed remains from North America and Europe unambiguously belong to the family. Seeds from the Eocene of North America show some similarities to the modern Schisandra glabra from North America, while fossils from Europe show more similarities to modern Asian species.  相似文献   

15.
Annona emarginata (Annonaceae) has two morphological variations (A. emarginata ‘mirim’ and A. emarginata ‘terra-fria’). The species has agricultural value and produces specialized metabolites of pharmacological interest. The objective of this work was to analyze whether chemical and morphological differences contribute to differentiate A. emarginata ‘terra-fria’ from A. emarginata ‘mirim’, as chemophenetic variations of A. emarginata. The analysis of chemical compounds was based on the quantification, profile of root alkaloids and on the leaves volatile profile, together with morphometric analyses of the leaf blade. The samples were collected in three phenological stages (flowering, fruiting, and vegetative) at two places in São Paulo, Brazil. Differences in the composition of the alkaloid profile and leaf volatiles (in both places and in the three phenological stages) allowed us to separate the two morphotypes by multivariate statistical analysis. These differences agreed with the leaf blade morphology and flower color. This first chemophenetic report of A. emarginata demonstrates that, in addition to morphological variations, the specialized metabolism of roots and leaves can be phytochemical characters, which suggest the existence of at least morphochemotypes of A. emarginata.  相似文献   

16.
17.
Scirpus L. s.l. is well known as one of the polyphyletic groups in Cyperaceae. Recent molecular phylogenetic studies clearly suggested that Scirpus s.l. should be separated into several independent genera. In this study, we intend to present the morphological variations and patterns of phenotypic evolution based on molecular phylogeny of Korean Scirpus s.l. Five genera, including 21 taxa from Korean Scirpus s.l., were examined: three species of Bolboschoenus, three species of Schoenoplectus, eight species of Schoenoplectiella including one hybrid, five species of Scirpus, and two species of Trichophorum. For morphological analyses, 23 and 48 characters were selected from vegetative and reproductive organs, respectively. Molecular phylogeny was inferred from a nuclear ribosomal internal transcribed spacer, the chloroplast rbcL gene, and the chloroplast trnL-F region. Distinct characteristics and quantitative variation was presented for identification of the five genera and their species. A pronounced pattern of morphological character change was reduction, although many other character states seem to be homoplastic. We suggest that the reduction of phenotypic characteristics has been expressed in terms of condensation of internodes, reduction of leaf blade, and simplification of inflorescence among five genera of Korean Scirpus s.l.  相似文献   

18.
A morphological, anatomical, and molecular study of the two genera (Heterocladia and Trigenea) and three species of the tribe Heterocladieae (Rhodomelaceae, Ceramiales) is presented. First collections of male and female gametophytes of Heterocladia australis Decaisne and Trigenea umbellata J. Agardh and of tetrasporophytes of the type species of Trigenea, T. australis Sonder, have allowed a much clearer assessment of these taxa from a classical morphological standpoint. Reproductive and vegetative characters of the two Trigenea species are shown to be virtually identical to those of Heterocladia, which differs from Trigenea principally in having both flattened and terete lateral branches, as opposed to exclusively terete axes throughout. As a consequence, we propose to transfer the Trigenea species to the earlier‐named genus Heterocladia as H. caudata L. Phillips, H.‐G. Choi, G.W. Saunders et Kraft, nom. nov. and H. umbellata ( J. Agardh) L. Phillips, H.‐G. Choi, G.W. Saunders et Kraft, comb. nov. The close relationship of the three species is supported by molecular data, as nucleotide sequences of the 18S rRNA gene from each are nearly identical. The same sequences from species of eight other rhodomelaceous genera plus those from five outgroup taxa are analyzed to provide grounds for preliminary phylogenetic inferences about the position of the Heterocladieae in the Rhodomelaceae. Both the Heterocladieae and the Rhodomelaceae are monophyletic taxa in our analyses, the Heterocladieae grouping weakly with the Bostrychieae and the problematic Australian endemic genus Sonderella, the latter yet to be assigned to a tribe. Representatives of groups with which Heterocladia has been associated previously, such as the Lophothalieae and Brongniartelleae, appear to be only distantly related, although many more taxa need to be analyzed before the systematic position of the genus becomes clear.  相似文献   

19.
20.
The anatomy and morphology of leaves in Carex have the potential to be taxonomically useful. However, studies on the variability of leaf characteristics in the genus are sparse. Researchers therefore risk using leaf anatomical characters without the knowledge of whether they are consistent in a species. We examined 22 qualitative and seven quantitative leaf anatomy characters from transverse leaf sections to test their consistency across 11 Carex spp. The characters were clearly described and primarily microscopic. Some characters were found to exhibit high levels of intraspecific variation, whereas other characters exhibited high levels of consistency in a species, including the shape of the leaf section, the density of papillae and the size of epidermal cells. Caution must be applied when choosing leaf anatomy to delimit taxa because of the intraspecific variability found in some characters, but sufficient numbers of invariant characters exist to provide useful taxonomic separation. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 371–384.  相似文献   

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