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1.
DNA sequences of the 5' end of the chloroplast ndhF gene for 15 species of Caryophyllaceae have been analyzed by parsimony and neighbor-joining analyses. Three major clades are identified, with little or no support for monophyly of traditionally recognized subfamilies. The first of the three major clades identified (Clade I) is constituted by part of the subfamily Paronychioideae. It includes members of the tribe Paronychieae and members of tribe Polycarpeae. The second (Clade II) contains members of the Paronychieae exclusively. Tribe Paronychieae is thus apparently polyphyletic and tribe Polycarpeae is at least paraphyletic. The third clade (Clade III) includes members of subfamilies Alsinoideae and Caryophylloideae along with the genus Spergularia. The genus Scleranthus is also part of Clade III, while Drymaria groups with the other genera of tribe Polycarpeae in Clade II. We conclude that morphological characters previously used to delimit subfamilial groupings in the Caryophyllaceae are apparently unreliable estimators of phylogeny.  相似文献   

2.
A new genus and species (Caryophylloflora paleogenica genus and species nova G. J. Jord. & Macphail) are proposed for a fossil inflorescence found in Middle-Late Eocene sediments at Locharbour, northeastern Tasmania, Australia. A parsimony analysis of 75 extant species of the order Caryophyllales and five outgroups placed the fossil within Caryophyllaceae, either subfamily Alsinoideae or Caryophylloideae. The analysis used molecular (rbcL and/or matK), morphological, and anatomical data for the extant species and morphological data for the fossil. Tests on extant species imply that the placement of the fossil should be convincing. The fossil appears to be of a lineage distinct from any extant Australian Caryophyllaceae. In situ pollen are consistent with the form species, Periporopollenites polyoratus. This relatively simple pollen type first appears in Australia and New Zealand in the Late Cretaceous, the oldest known record of the Caryophyllaceae. The last appearance of P. polyoratus in Australia is in the Oligocene, and extant Australian members of the Caryophyllaceae are best interpreted as having evolved from species that dispersed from elsewhere during the Neogene or Quaternary.  相似文献   

3.
《Flora》2007,202(4):281-292
The xylem and phloem of 88 Caryophyllaceae from subtropical and temperate regions mainly in Western Europe and the Canary Islands are described and analysed. They are compared with their taxonomic classification, and assigned to their ecological range. The xylem of different life forms (herbaceous plants, dwarf shrubs and shrubs) consists mainly of parenchyma and small vessels that are 20–50 μm in diameter in earlywood. They have simple perforations and pits are pseudosclariform and scalariform. The axial parenchyma is mostly pervasive or paratracheal, and the ray cells are exclusively upright or square. The anatomy of the subfamily Alsinoideae is homogeneous and characterised by the absence of libriform fibres, large rays, crystal druses and sclereids in the cortex. The subfamily Caryophylloideae is less homogeneous and mainly characterised by the presence of crystal druses on the xylem and phloem, as well as the presence of intra-annual fibre bands. The subfamily Paronychioideae is heterogeneous; included phloem is most characteristic. Ecological trends are clearly expressed by the age of plants and the average annual radial growth rates. Plants tend to grow older and slower at higher altitudes. The presence of intra-annual fibre bands in the xylem is characteristic of Caryophylloideae at lower altitudes. The study suggests that taxonomic and ecological classifications and large-scale ecological trend studies must be based on large and homogeneous datasets and well-defined anatomical features.  相似文献   

4.
Cerdia is a poorly understood genus of minute cushiony plants endemic to Mexico that is traditionally placed in subfamily Paronychioideae, tribe Polycarpeae (Caryophyllaceae). Morphological observations and phylogenetic analysis of ITS DNA sequences were carried out to determine the number of species, heretofore controversial, that constitute the genus as well as its position within Caryophyllaceae. Samples of Cerdia were collected through its entire range of distribution and together with previous specimens were used in morphological analyses. Nineteen terminal taxa were considered in a phylogenetic analysis with representatives of the different lineages in Caryophyllaceae. Results indicated that Cerdia is a monotypic genus, including only one variable species, C .  virescens , but its phylogenetic affinities remain doubtful.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 1–13.  相似文献   

5.
The androecium of the Caryophyllaceae is varied, ranging from a two-whorled condition to a single stamen. A number of species belonging to the three subfamilies, Caryophyl-loideae, Alsinoideae and Paronychioideae have been studied ontogenetically with the SEM to understand their peculiar androecial development in the broader context of the Caryophyllales alliance. Although patterns of initiation are highly variable among species, there are three ontogenetic modes of stamen initiation: all stamens simultaneous within a whorl, the antepetalous stamens simultaneous and the antesepalous sequentially with a reversed direction, or both whorls sequentially with or without a reversed direction. The most common floral (ontogenetic) sequence of the Caryophyllaceae runs as follows: five sepals (in a 2/5 sequence), the stamens in front of the three inner sepals successively, stamens opposite the two outermost sepals, five antepetalous stamens (simultaneously or in a reversed spiral superimposed on the spiral of the antesepalous stamens), five outer sterile (petaloid) organs arising before, simultaneously or after the antesepalous stamens, often by the division of common primordia. A comparison with the floral configurations of the Phytolaccaceae and Molluginaceae indicates that the outer petaline whorl of the Caryophyllaceae corresponds positionally to the alternisepalous stamens of somePhytolacca, such asP. dodecandra. The difference withP. dodecandra lies in the fact that an extra inner or outer whorl is formed in the Caryophyl-laceae, in alternation with the sepals. A comparable arrangement exists in the Molluginaceae, though the initiation of stamens is centrifugal. A comparison of floral ontogenies and the presence of reduction series in the Caryophyllaceae support the idea that the pentamerous arrangement is derived from a trimerous prototype. Petals correspond to sterillized stamens and are comparable to two stamen pairs opposite the outer sepals and a single stamen alternating with the third and fifth sepals. Petals are often in a state of reduction; they may be confused with staminodes and they often arise from common stamenpetal primordia. The antesepalous stamen whorl represents an amalgamation of two whorls: initiation is reversed with the stamens opposite the fourth and fifth formed sepals arising before the other, while the stamens opposite the first and second formed sepals are frequently reduced or lost. Reductive trends are correlated with the mode of initiation of the androecium, as well as changes in the number of carpels, and affect the antesepalous and antepetalous whorls in different proportions. It is concluded that the androecium of the Caryophyllaceae is pseudodiplos-temonous and is not comparable to diplostemonous forms in the Dilleniidae and Rosidae. The basic floral formula of Caryophyllaceae is as follows: sepals 5—petals 5 (sterile stamens)—antesepalous stamens 3+2—antepetalous stamens 5 gynoecium 5.  相似文献   

6.
Bayesian, maximum‐likelihood, and maximum‐parsimony phylogenies, constructed using nucleotide sequences from the plastid gene region trnK‐matK, are employed to investigate relationships within the Cactaceae. These phylogenies sample 666 plants representing 532 of the 1438 species recognized in the family. All four subfamilies, all nine tribes, and 69% of currently recognized genera of Cactaceae are sampled. We found strong support for three of the four currently recognized subfamilies, although relationships between subfamilies were not well defined. Major clades recovered within the largest subfamilies, Opuntioideae and Cactoideae, are reviewed; only three of the nine currently accepted tribes delimited within these subfamilies, the Cacteae, Rhipsalideae, and Opuntieae, are monophyletic, although the Opuntieae were recovered in only the Bayesian and maximum‐likelihood analyses, not in the maximum‐parsimony analysis, and more data are needed to reveal the status of the Cylindropuntieae, which may yet be monophyletic. Of the 42 genera with more than one exemplar in our study, only 17 were monophyletic; 14 of these genera were from subfamily Cactoideae and three from subfamily Opuntioideae. We present a synopsis of the status of the currently recognized genera.
© The Willi Hennig Society 2011.  相似文献   

7.
新疆石竹科的繁缕亚科、裸果木亚科共有植物14属63种3变种。占新疆石竹总属数66.7%总种数48.2%。从垂直分布来看,主要分布于阿尔泰山和天山的亚高山草甸带和森林草甸带,昆仑山的高寒荒漠草原也有一定的分布。从水平分布看,主要有五个分布较集中的区域,即:阿尔泰泰山地,准噶尔西部山地,天山中西部山地、天山东部山地、昆仑山和帕米尔高原。在区系组成中,北温带成分21种,占31.9%;温带亚洲成分14种,  相似文献   

8.
The family Asclepiadaceae (Dicotyledones) was created by Brown in 1810 by splitting in two the family Apocynaceae of Jussieu established in 1789. The morphological characters used to make this distinction were mainly palynological, such as presence of tetrads or pollinia and number and orientation of pollinia. Those characters, still used in higher taxonomic delimitation (families, subfamilies, and tribes), are here critically reexamined and compared to a molecular phylogeny obtained with one of the more variable plastid genes (matK) of 46 species in the order Gentianales. In this molecular phylogeny, Asclepiadaceae form a monophyletic group derived from within Apocynaceae. Each of the subfamilies of Asclepiadaceae is monophyletic and based on reliable palynological characters, but palynological characters are not useful to delimit tribes of the subfamily Asclepiadoideae. Based on the molecular data, these tribes have undergone parallelisms in several reproductive traits.  相似文献   

9.
Ladybird beetles (family Coccinellidae) are a species-rich, ecologically diverse group of substantial agricultural significance, yet have been consistently problematic to classify, with evolutionary relationships poorly understood. In order to identify major clades within Coccinellidae, evaluate the current classification system, and identify likely drivers of diversification in this polyphagous group, we conducted the first simultaneous Bayesian analysis of morphological and multi-locus molecular data for any beetle family. Addition of morphological data significantly improved phylogenetic resolution and support for early diverging lineages, thereby better resolving evolutionary relationships than either data type alone. On the basis of these results, we formally recognize the subfamilies Microweisinae and Coccinellinae sensu?lipiński (2007). No significant support was found for the subfamilies Coccidulinae, Scymninae, Sticholotidinae, or Ortaliinae. Our phylogenetic results suggest that the evolutionary success of Coccinellidae is in large part attributable to the exploitation of ant-tended sternorrhynchan insects as a food source, enabled by the key innovation of unusual defense mechanisms in larvae.  相似文献   

10.
Ranunculus is a large genus with a worldwide distribution. Phylogenetic analyses of c. 200 species of Ranunculus s.l. based on sequences of the nrITS using maximum parsimony and Bayesian inference yielded high congruence with previous cpDNA restriction site analyses, but strongly contradict previous classifications. A large core clade including Ranunculus subg. Ranunculus, subg. Batrachium, subg. Crymodes p.p., Ceratocephala, Myosurus, and Aphanostemma is separated from R. subg. Ficaria, subg. Pallasiantha, subg. Coptidium, subg. Crymodes p.p., Halerpestes, Peltocalathos, Callianthemoides, and Arcteranthis. Within the core clade, 19 clades can be described with morphological and karyological features. Several sections are not monophyletic. Parallel evolution of morphological characters in adaptation to climatic conditions may be a reason for incongruence of molecular data and morphology-based classifications. In some mountainous regions, groups of closely related species may have originated from adaptive radiation and rapid speciation. Split decomposition analysis indicated complex patterns of relationship and suggested hybridization in the apomictic R. auricomus complex, R. subg. Batrachium, and the white-flowering European alpines. The evolutionary success of the genus might be due to a combination of morphological plasticity and adaptations, hybridization and polyploidy as important factors for regional diversification, and a broad range of reproductive strategies.  相似文献   

11.
12.
The infrageneric phylogeny and temporal divergence of Sorghum were explored in the present study. Sequence data of two low-copy nuclear (LCN) genes, phosphoenolpyruvate carboxylase 4 (Pepc4) and granule-bound starch synthase I (GBSSI), from 79 accessions of Sorghum plus Cleistachne sorghoides together with those from outgroups were used for maximum likelihood (ML) and Bayesian inference (BI) analyses. Bayesian dating based on three plastid DNA markers (ndhA intron, rpl32-trnL, and rps16 intron) was used to estimate the ages of major diversification events in Sorghum. The monophyly of Sorghum plus Cleistachne sorghoides (with the latter nested within Sorghum) was strongly supported by the Pepc4 data using BI analysis, and the monophyly of Sorghum was strongly supported by GBSSI data using both ML and BI analyses. Sorghum was divided into three clades in the Pepc4, GBSSI, and plastid phylograms: the subg. Sorghum lineage; the subg. Parasorghum and Stiposorghum lineage; and the subg. Chaetosorghum and Heterosorghum lineage. Two LCN homoeologous loci of Cleistachne sorghoides were first discovered in the same accession. Sorghum arundinaceum, S. bicolor, S. x drummondii, S. propinquum, and S. virgatum were closely related to S. x almum in the Pepc4, GBSSI, and plastid phylograms, suggesting that they may be potential genome donors to S. almum. Multiple LCN and plastid allelic variants have been identified in S. halepense of subg. Sorghum. The crown ages of Sorghum plus Cleistachne sorghoides and subg. Sorghum are estimated to be 12.7 million years ago (Mya) and 8.6 Mya, respectively. Molecular results support the recognition of three distinct subgenera in Sorghum: subg. Chaetosorghum with two sections, each with a single species, subg. Parasorghum with 17 species, and subg. Sorghum with nine species and we also provide a new nomenclatural combination, Sorghum sorghoides.  相似文献   

13.
14.
The relationships among and within the main lineages of the order Clupeiformes have been explored in few morphological studies and still remain poorly understood. Using whole mitogenome sequences, we inferred the relationships among 25 clupeiform species, sampled from each clupeiform family and subfamily, and a large selection of non-clupeiform teleosts. Our character sets, including unambiguously aligned, concatenated mitogenome sequences that we have divided into four (1st and 2nd codon positions, tRNA genes, and rRNA genes) or five partitions (same as before plus the transversions at 3rd codon positions, using 'RY' coding), were analyzed by the partitioned Bayesian method. The result strongly supported the monophyly of the Clupeiformes within the Otocephala, with Denticeps clupeoides as the sister group of a clade comprising all the remaining clupeiforms species (= suborder Clupeoidei). Within the Clupeoidei, the family Engraulidae was the sister group of the remaining taxa, comprising members of Sundasalangidae, Pristigasteridae, Clupeidae and Chirocentridae. Relationships among the latter four families remained ambiguous. In particular, the position of the Chirocentridae was difficult to estimate possibly owing to its higher molecular evolutionary rate. Of the five subfamilies in the family Clupeidae, monophylies of three (Alosinae, Clupeinae and Dorosomatinae) were statistically rejected. Instead, our mitogenomic data provide strong support for new clades within the Clupeidae, some of which are composed of members of more than one of the previously accepted subfamilies.  相似文献   

15.
Abstract Phylogenetic relationships of Pamphagidae were examined using cytochrome oxidase subunit II (COII) mtDNA sequences (684 bp). Twenty‐seven species of Acridoidea from 20 genera were sequenced to obtain mtDNA data, along with four species from the GenBank nucleotide database. The purpose of this study was analyzing the phylogenetic relationships among subfamilies within Pamphagidae and interpreting the phylogenetic position of this family within the Acridoidea superfamily. Phylogenetic trees were reconstructed using neighbor‐joining (NJ), maximum parsimony (MP) and Bayesian inference (BI) methods. The 684 bp analyzed fragment included 126 parsimony informative sites. Sequences diverged 1.0%–11.1% between genera within subfamilies, and 8.8%–12.3% between subfamilies. Amino acid sequence diverged 0–6.1% between genera within subfamilies, and 0.4%–7.5% between subfamilies. Our phylogenetic trees revealed the monophyly of Pamphagidae and three distinct major groups within this family. Moreover, several well supported and stable clades were found in Pamphagidae. The global clustering results were similar to that obtained through classical morphological classification: Prionotropisinae, Thrinchinae and Pamphaginae were monophyletic groups. However, the current genus Filchnerella (Prionotropisinae) was not a monophyletic group and the genus Asiotmethis (Prionotropisinae) was a sister group of the genus Thrinchus (Thrinchinae). Further molecular and morphological studies are required to clarify the phylogenetic relationships of the genera Filchnerella and Asiotmethis.  相似文献   

16.
The phylogenetic relationships of microhylid frogs are poorly understood. The first molecular phylogeny for continental African microhylids is presented, including representatives of all subfamilies, six of the eight genera, and the enigmatic hemisotid Hemisus. Mitochondrial 12S and 16S rRNA sequence data were analysed using parsimony, likelihood and Bayesian methods. Analyses of the data are consistent with the monophyly of all sampled subfamilies and genera. Hemisus does not nest within either brevicipitines or non-brevicipitines. It is possibly the sister group to brevicipitines, in which case brevicipitines might not be microhylids. Phrynomantis and Hoplophryne potentially group with non-African, non-brevicipitine microhylids, in agreement with recent morphological and molecular data. Within brevicipitines, Breviceps is recovered as the sister group to a clade of Callulina+Spelaeophryne+Probreviceps. The relationships among the genera within this latter clade are unclear, being sensitive to the method of analysis. Optimal trees suggest the Probreviceps macrodactylus subspecies complex might be paraphyletic with respect to P. uluguruensis, corroborating preliminary morphological studies indicating that P. m. rungwensis may be a distinct species. P. m. loveridgei may be paraphyletic with respect to P. m. macrodactylus, though this is not strongly supported. Some biogeographic hypotheses are examined in light of these findings.  相似文献   

17.
The Aizoaceae is the largest family of leaf succulent plants, and most of its species are endemic to southern Africa. To evaluate subfamilial, generic, and tribal relationships, we produced two plastid DNA data sets for 91 species of Aizoaceae and four outgroups: rps16 intron and the trnL-F gene region (both the trnL intron and the trnL-F intergenic spacer). In addition, we generated two further plastid data sets for 56 taxa restricted to members of the Ruschioideae using the atpB-rbcL and the psbA-trnH intergenic spacers. In the combined tree of the rps16 intron and trnL-F gene region, three of the currently recognized subfamilies (Sesuvioideae, Mesembryanthemoideae, and Ruschioideae) are each strongly supported monophyletic groups. The subfamily Tetragonioideae is polyphyletic, with Tribulocarpus as sister to the Sesuvioideae and Tetragonia embedded in the Aizooideae. Our study showed that the group consisting of the Sesuvioideae, Aizooideae, and Tetragonioideae does not form a monophyletic entity. Therefore, it cannot be recognized as a separate family in order to accommodate the frequently used concept of the Mesembryanthemaceae or "Mesembryanthema," in which the subfamilies Mesembryanthemoideae and Ruschioideae are included. We also found that several genera within the Mesembryanthemoideae (Mesembryanthemum, Phyllobolus) are not monophyletic. Within the Ruschioideae, our study retrieved four major clades. However, even in the combined analysis of all four plastid gene regions, relationships within the largest of these four clades remain unresolved. The few nucleotide substitutions that exist among taxa of this clade point to a rapid and recent diversification within the arid winter rainfall area of southern Africa. We propose a revised classification for the Aizoaceae.  相似文献   

18.
An exception to the generally conservative nature of plastid gene evolution is the gene coding for the beta" subunit of RNA polymerase, rpoC2. Previous work by others has shown that maize and rice have an insertion in the coding region of rpoC2, relative to spinach and tobacco. To assess the distribution of this extra coding sequence, we surveyed a broad phylogenetic sample comprising 55 species from 17 angiosperm families by using Southern hybridization. The extra coding sequence is restricted to the grasses (Poaceae). DNA sequence analysis of 11 species from all five subfamilies within the grass family demonstrates that the extra sequence in the coding region of rpoC2 is a repetitive array that exhibits more than a twofold increase in nucleotide substitution, as well as a large number of insertion/deletion events, relative to the adjacent flanking sequences. The structure of the array suggests that slipped-strand mispairing causes the repeated motifs and adds to the mechanisms through which the coding sequence of plastid genes are known to evolve. Phylogenetic analyses based on the sequence data from grass species support several relationships previously suggested by morphological work, but they are ambiguous about broad relationships within the family.   相似文献   

19.
Euphorbia (Euphorbiaceae) comprises over 2150 species and is thus the second-largest genus of flowering plants. In Europe, it is represented by more than 100 species with highest diversity in the Mediterranean area; the majority of taxa belong to subgenus Esula Pers., including about 500 taxa. The few available phylogenetic studies yielded contrasting results regarding the monophyly of subg. Esula, and the phylogenetic relationships among its constituents remain poorly understood. We have sampled DNA sequences from the nuclear ribosomal internal transcribed spacer (ITS) and the plastid trnT-trnF region from about 100, predominantly European taxa of subg. Esula in order to infer its phylogenetic history. The plastid data support monophyly of subg. Esula whereas the ITS phylogeny, which is generally less resolved, is indecisive in this respect. Although some major clades have partly incongruent positions in the ITS and plastid phylogenies, the taxonomic content of the major terminal clades is congruent in both trees. As traditional sectional delimitations are largely not corroborated, an improved classification is proposed. Character state reconstruction illustrates that the annual life form developed independently several times in different clades of subgenus Esula from perennial ancestors, and that several morphological traits used in previous classifications of Euphorbia developed in parallel in different lineages.  相似文献   

20.
Magnoliaceae, an assemblage of early diverged angiosperms, comprises two subfamilies, speciose Magnolioideae with approximately 300 species in varying numbers of genera and monogeneric Liriodendroideae with two species in Liriodendron L. This family occupies a pivotal phylogenetic position with important insights into the diversification of early angiosperms, and shows intercontinentally disjunct distribution patterns between eastern Asia and the Americas. Widespread morphological homogeneity and slow substitution rates in Magnolia L. s.l. resulted in poorly supported phylogenetic relationships based on morphology or molecular evidence, which hampers our understanding of the genus’ temporal and spacial evolution. Here, based on the newly generated genome skimming data for 48 Magnolia s.l. species, we produced robust Magnolia phylogenies using genome-wide markers from both plastid genomes and single nucleotide polymorphism data. Contrasting the plastid and nuclear phylogenies revealed extensive cytonuclear conflicts in both shallow and deep relationships. ABBA-BABA and PhyloNet analyses suggested hybridization occurred within sect. Yulania, and sect. Magnolia, which is in concordance with the ploidy level of the species in these two sections. Divergence time estimates and biogeographic reconstruction indicated that the timing of the three tropical Magnolia disjunctions coincided with the mid-Eocene cooling climate and/or late Eocene climate deterioration, and two temperate disjunctions occurred much later, possibly during the warm periods of the Miocene, hence supporting the boreotropical flora concept of Magnolia s.l.  相似文献   

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