首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
狭义五福花科(Adoxaceae.s.s)仅含3属4种,但该科的物种分化、系统发育和分类一直存在争议。本文通过测定东方五福花和血满草的ITS(核糖体DNA内转录间隔区)序列,构建了包括狭义五福花科(4种)、广义忍冬科接骨木属、荚属以及其余4属植物在内的系统发育树。研究结果不支持狭义五福花科内根据形态学证据做出的系统发育假设四福花不是该科中最早分化出来的种;该物种与五福花属的两个物种形成一个单系群,与另一分支华福花属相对应。该科中3个物种,四福花、五福花和华福花之间的分化主要是在二倍体水平上的异域分化,而东方五福花则是通过多倍化形成的。粗略的时间估算表明这些物种之间的分化较晚,可能在第三纪末至第四纪早中期,与青池高原近期强烈隆升以及冰期气候反复变化形成的环境变迁密切相关。  相似文献   

2.
五福花科花部维管结构的比较研究   总被引:3,自引:3,他引:0  
首次报道了华福花属华福花Sinadoxacorydalifolia和东方五福花Adoxaorientalis花部维管结构,并对五福花科3属4种植物的花部维管系统进行了比较研究。3属4种的花部维管系统表现出不同的对称性和不同的复化、减化以及不同的融合程度。基于花部维管系统的证据,本工作支持四福花属四福花Tetradoxaomeiensis为科内原始类群代表的看法。  相似文献   

3.
五福花科植物的染色体数目及其系统学意义   总被引:3,自引:3,他引:0  
  相似文献   

4.
Sequences of the chloroplast trnL-F region and 3(') end ndhF gene were used to elucidate phylogenetic relationships and the delimitation of families within Dipsacales s.l. Parsimony analyses of individual and combined data were conducted using maximum parsimony method. The most parsimonious tree based on combined trnL-F and 3(') end ndhF data set recognizes seven major clades of Dipsacales s.l. with the following relationships: Apiales (Adoxaceae ((Diervillaceae, Caprifoliaceae s.str.) (Linnaeaceae (Morinaceae (Dipsacaceae, Valerianaceae))))). Both Sambucus and Viburnum have close relationships with Adoxaceae, supporting their inclusion in this family. Caprifoliaceae s.l. (excluding Sambucus and Viburnum) is polyphyletic, and comprises three clades or families, i.e., Linnaeaceae (Abelia, Dipelta, Kolkwitzia, and Linnaea), Diervillaceae (Weigela and Diervilla) and Caprifoliaceae s.str. (Heptacodium, Leycesteria, Lonicera, Symphoricarpos, and Triosteum). This study focuses on the systematic position of Heptacodium, Triplostegia, and Morinaceae; and suggests that Heptacodium is closely related to the other Caprifoliaceae s.str.; Triplostegia is a sister to Dipsacaceae; Morinaceae, which has an affinity with Dipsacaceae, is possibly a sister group with Dipsacaceae-Valerianaceae clade. Our results are highly congruent with those of and.  相似文献   

5.
Sinadoxa corydalifolia is the only species of Sinadoxa (Adoxaceae) with the aberrant morphology. This species has become extremely endangered in the Qinghai-Tibetan Plateau. To provide a population-level genetic profile for investigation and conservation of genetic diversity of this species, we developed 10 new microsatellite loci for this species by the combining biotin capture method. About 31 microsatellites were screened from the library, 10 of the screened microsatellites are polymorphic. The number of alleles per locus in 18 individuals ranged from 3 to 11, expected heterozygosity and observed heterozygosity ranged from 0.3071 to 0.6243 and from 0.1675 to 0.4357, respectively. We further performed cross-priming tests of these primers in another species of the Adoxaceae: Adoxa moschatellina and found 9 of 10 successfully amplified the targeted sequences. These newly developed loci provide a useful tool to investigate the genetic diversity and design the conversation measures of S. corydalifolia and study the genetic divergence and the initial speciation pattern between it and the related species in the Adoxaceae.  相似文献   

6.
从叶绿体DNA trnL-F序列论双参属的归属问题   总被引:13,自引:0,他引:13  
双参属Triplostegia Wall.ex DC.由分布于东南亚地区的2个种组成,为多年生草本植物。它的归属一直存在争议,有时置于川续断科Dipsacaceae或败酱科Valerianaceae,有时单立一科,即双参科Triplostegiaceae。本研究对广义川续断目Dipsacales s.l.的21种植物(分别来自于败酱科、川续断科、双参属、刺参属Morina、广义忍冬科Caprifoliaceae s. l.、五福花科 Adoxaceae)和外类群人参Panax schin-seng Nees.的叶绿体 DNA trnL-F区进行了测序,并建立系统发育树状图。结果显示,败酱科、川续断科、双参属、刺参属和广义忍冬科的4个属(双盾木属Dipelta、虫胃实属Kolkwitzia、六道木属Abelia和北极花属Linnaea)形成 了一个单系群并得到了很强的支持(100% bootstrap);双参属与川续断科有更近的关系,建议作为一个亚科置于川续断科;广义忍冬科为一多系类群;而刺参属与其他广义川续断目类群之间的关系尚不能确定。  相似文献   

7.
The phylogenetie relationships of Triplostegia Wall. ex DC., comprising two species of perennial herbs from southeastern Asia, have long been in dispute. This genus was placed in either Dipsacaceae or Valerianaceae or in a family of its own, Triplostegiaceae. In this paper, the chloroplast DNA (cpDNA) trn L-F regions of 21 species in the Dipsacales s. l. (including Valerianaceae, Dipsacaceae, Triplostegia, Morina, Caprifoliaceae s. l. and Adoxaceae) and an outgroup Panax schin-seng Nees. were amplified and sequenced. The phylogenetic relationships among these 22 species were constructed based on trn L-F sequences. The results demonstrated that Valerianaceae, Dipsacaceae, Triplostegia, Morina and four genera from the Caprifoliaceae s. l. form a monophyletic group with a strong support (100% bootstrap). Triplostegia, a sister group to Dipsacaceae, is close enough to be placed in the Dipsacaceae as a subfamily. The traditional Caprifoliaceae s.l. are polyphyletic, and relationships of Morina among the groups within Dipsacales s. l. are uncertain. Key words Triplostegia; Caprifoliaceae s. l.; Morina; Dipsacales s. l.; trnL-F sequences; Sys-tematic position  相似文献   

8.
Few genetic data are currently available to assess patterns of population differentiation and speciation in planktonic taxa that inhabit the open ocean. A phylogenetic study of the oceanic copepod family Eucalanidae was undertaken to develop a model zooplankton taxon in which speciation events can be confidently identified. A global survey of 20 described species (526 individuals) sampled from 88 locations worldwide found high levels of cryptic diversity at the species level. Mitochondrial (16S rRNA, CO1) and nuclear (ITS2) DNA sequence data support 12 new genetic lineages as highly distinct from other populations with which they are currently considered conspecific. Out of these 12, at least four are new species. The circumglobal, boundary current species Rhincalanus nasutus was found to be a cryptic species complex, with genetic divergence between populations unrelated to geographic distance. 'Conspecific' populations of seven species exhibited varying levels of genetic differentiation between Atlantic and Pacific basins, suggesting that continental landmasses form barriers to dispersal for a subset of circumglobal species. A molecular phylogeny of the family based on both mitochondrial (16S rRNA) and nuclear (ITS2, 18S rRNA) gene loci supports monophyly of the family Eucalanidae, all four eucalanid genera and the 'pileatus' and 'subtenuis' species groups.  相似文献   

9.
以APGⅢ定义的川续断目(Dipsacales)忍冬科(Caprifoliaceae)和五福花科(Adoxaceae)为研究对象,基于已有的川续断目分子系统树和花粉形态数据,分析了忍冬科25属和五福花科5属的花粉形态多样性,采用简约法(Fitch Parsimony)推测花粉祖征和演化式样,寻找共衍征和分类性状.选择花粉萌发孔数目、萌发孔类型、花粉形状、大小和外壁纹饰五个关键性状推断了其演化式样.研究表明:三孔沟、近球形、较小花粉、网状纹饰是川续断目花粉祖征.长球型、中等和较大花粉,以及刺状纹饰是忍冬科的共衍征,支持忍冬科和科下分支为单系群.忍冬科花粉刺状纹饰和五福花科花粉网状纹饰明显将两个科区分开来.通过追溯性状演化分析,支持将七子花属(Heptacodium)置于忍冬族(Caprifolieae),以及Zabelia置于刺续断科的观点.  相似文献   

10.
The pollen morphology of 54 samples representing 12 genera and 31 species was investigated with the aid of scanning electron microscope. Observed were pollen grains of Sambucus, Viburnum, Lonicera, Leycesteria, Heptacodium, Linnaea, Abelia, Dipelta, Kolkwitzia, Symphoricarpos, Triosteum, Weigela. Based on the shape, size, position and number of aperture, exine sculpture, three types are recognized: 1. Pollen grains subprolate, less frequently prolate, rather small, 3-colporate, exine reticulate, as in Sambucus, Viburnum. 2. Mostly spheroidal, subolate, bigger than the former, also 3-colporate, exine spinulose as in Lonicera, Leycesteria, Heptacodium, Triosteum, Linnaea, Abelia, Dipelta, Kolkwitzia, Symphoriocarpos, Weigela. 3. Spheriodal, more or less flattend, exine scabrous as in Abelia section Zabelia and Lonicera section Isoxylosteum. 1. The systematic position of Caprifoliaceae: It has been generally treated as a member of the order Rubiales together with Rubiaceae, Valeriaceae and Dipsacaceae on floral characters. In respect to serological character, it has a close relationship with Cornaceae, and was placed in Araliales. The above stated 2nd and 3rd types of pollen grains are similar to those of Patrinia (Valerianaceae), Scabiosa (Adoxaceae), Cornus (Cornaceae), and the pollen grains of the 1st type are similar to those of Styraceae, Genetianaceae and Araliaceae. Taking the information so far available into consideration, the authors agree to the Cronquists treatment retaining Caprifoliaceae in the order Dipsacales together with Adoxaceae, Valerianaceae and Dipsacaceae. 2. The division of tribes: Formerly Sambuceae included the genera Sambucus and Viburnum. Fritsch (1891) segregated Viburnum from Sambuceae and suggested a new tribe Viburneae including Triosteum. There is distinct difference in palynological features between these two genera. The exine sculpture of Viburnum is reticulate, but that of Triosteum is spinulose. It is reasonable to separate another new tribe, Triosteae, from Viburneae. 3. The pollen morphorlogy of several Chinese endemic genera, such as Heptacodium, Dipelta, Kolkwitzia resembles that of Lonicera, Leycesteria, Linnaea, Symphoricarpos, Abelia, Triosteum. This evidence supports the foregoing treatment including them in Caprifoliaceae. 4. Two different exine sculptures are shown in sections of the genera Abelia and Lonicera. In Abelia the exine of the section Euabelia is spinulose, but that of the section Zabelia is scabrous. Likewise, in Lonicera, the exine of the section Isoxylosteum is scabrous, while that of other sections such as Nintooa, Isika, Lonicera, subgenus Caprifolium, is spinulose. It shows that pollen morphology is one of diagnostic characters for section division.  相似文献   

11.
郭守玉  黄满荣 《菌物研究》2012,10(3):147-153
对具有北美东部和亚洲东部近缘生物地理学关系的大型地衣种类进行系统发育检测较少。笔者获得了石耳科中8个种10个样本nrDNA的ITS完整序列,并对本科中在分布上具有重要意义的4个种的生物地理学关系进行了分析和评估。通过对细胞核核糖体DNA变异性较强的ITS段碱基序列的比较分析,支持放射盘石耳(Umbilicaria muehlenbergii)、宾州疱脐衣(Lasallia pennsylvanica)为同种型间断分布,美味石耳(U.escu-lenta)和大叶石耳(U.mammulata)间已经达到了相当高的分化程度,为异种型间断分布。地理学分析显示该两种石耳的分化可能是由于太平洋的扩展和隔离所造成的结果。同种型间断分布种类的不同地区的样本之间的差异较小。推测了不同类型间断分布种类的分化时间,美味石耳与大叶石耳的分化发生在中新世(23~5.33 Mya)中期,白令海峡形成期间。  相似文献   

12.
Do phylogenies and branch lengths based on mitochondrial DNA (mtDNA) provide a reasonable approximation to those based on multiple nuclear loci? In the present study, we show widespread discordance between phylogenies based on mtDNA (two genes) and nuclear DNA (nucDNA; six loci) in a phylogenetic analysis of the turtle family Emydidae. We also find an unusual type of discordance involving the unexpected homogeneity of mtDNA sequences across species within genera. Of the 36 clades in the combined nucDNA phylogeny, 24 are contradicted by the mtDNA phylogeny, and six are strongly contested by each data set. Two genera (Graptemys, Pseudemys) show remarkably low mtDNA divergence among species, whereas the combined nuclear data show deep divergences and (for Pseudemys) strongly supported clades. These latter results suggest that the mitochondrial data alone are highly misleading about the rate of speciation in these genera and also about the species status of endangered Graptemys and Pseudemys species. In addition, despite a strongly supported phylogeny from the combined nuclear genes, we find extensive discordance between this tree and individual nuclear gene trees. Overall, the results obtained illustrate the potential dangers of making inferences about phylogeny, speciation, divergence times, and conservation from mtDNA data alone (or even from single nuclear genes), and suggest the benefits of using large numbers of unlinked nuclear loci. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 445–461.  相似文献   

13.
BACKGROUND AND AIMS: Boragineae is one of the main tribes of Boraginaceae, but delimitation and intergeneric classification of this group are unclear and have not yet been studied using DNA sequences. In particular, phylogenetic relationships in Anchusa s.l. still need to be elucidated in order to assess its taxonomic boundaries with respect to the controversial segregate genera Hormuzakia, Gastrocotyle, Phyllocara and Cynoglottis. METHODS: Phylogenetic relationships among 51 taxa of tribe Boragineae were investigated by comparative sequencing of the trnL(UAA) intron of the plastid genome and of the ITS1 region of the nuclear ribosomal DNA. Exemplar taxa from 16 genera of Boragineae and all subgenera of Anchusa s.l. were included, along with two selected outgroups from tribes Lithospermeae and Cynoglosseae. KEY RESULTS: Phylogenies generated by maximum parsimony and combined ITS1-trnL sequences support the monophyly of the tribe and a split into two clades, Pentaglottis and the remainder of Boragineae. The latter contains two large monophyletic groups. The first consists of three moderately to well-supported branches, Borago-Symphytum, Pulmonaria-Nonea and Brunnera. In the Pulmonaria-Nonea subclade, the rare endemic Paraskevia cesatiana is sister to Pulmonaria, and Nonea appears to be paraphyletic with respect to Elizaldia. The second main group corresponds to the well-supported clade of Anchusa s.l., with the megaphyllic, polyploid herb Trachystemon orientalis as sister taxon, although with low support. Anchusa s.l. is highly paraphyletic to its segregate genera and falls into four subclades: (1) Phyllocara, Hormuzakia, Anchusa subgenus Buglossum and A. subgenus Buglossoides; (2) Gastrocotyle; (3) A. subgenus Buglossellum and Cynoglottis; and (4) A. subgenus Anchusa, Lycopsis and Anchusella. All species of Anchusa subg. Anchusa, including the South African A. capensis, are included in a single unresolved clade. Anchusa subgenus Limbata is also included here despite marked divergence in floral morphology. The low nucleotide variation of ITS1 suggests a recent partly adaptive radiation within this group. CONCLUSIONS: Molecular data show that nine of the usually accepted genera of the Boragineae consisting of two or more species are monophyletic: Anchusella, Borago, Brunnera, Cynoglottis, Gastrocotyle, Hormuzakia, Nonea, Pulmonaria and Symphytum. In addition, the tribe includes the four monotypic genera Paraskevia, Pentaglottis, Phyllocara and Trachystemon. The morphologically well-characterized segregate genera in Anchusa s.l. are all confirmed by DNA sequences and should be definitively accepted. Most of the traditionally recognized subgenera of Anchusa are also supported as monophyletic groups by both nuclear and plastid sequence data. In order to bring taxonomy in line with phylogeny, the institution of new, independent generic entities for subgenera Buglossum, Buglossellum and Buglossoides and a narrower but more natural concept of Anchusa are advocated.  相似文献   

14.
Vicariant and climatic cycling speciation hypotheses of the 'sand gobies' belonging to the genera Pomatoschistus, Gobiusculus, Knipowitschia, and Economidichthys are tested using molecular phylogenies constructed of nuclear DNA (ITS1 locus) and mitochondrial DNA (12S and 16S fragments). These gobies are among the most abundant in the Eastern Atlantic-Mediterranean region, and play an important role in the ecosystem. Considerable ITS1 length differences, primarily due to the presence of several tandem repeats, were found between species and even within individuals. Therefore, phylogenetic analyses focused on fragments of the 12S and 16S mtDNA region that have been sequenced for 16 goby taxa. The 'sand gobies' clustered as a monophyletic group as proposed on morphological grounds. However, G. flavescens, E. pygmaeus, and K. punctatissima clustered within the Pomatoschistus species, pointing to a paraphyletic origin of these genera. Furthermore, the genetic divergence between P. minutus from the Adriatic Sea versus the Atlantic-Mediterranean region was as high as the divergence within the P. minutus complex, suggesting that P. minutus from the Adriatic Sea should be considered as a distinct species. The "star" phylogeny might suggest that these gobies evolved in a very short time period, possibly linked to the drastic alterations in the Mediterranean Sea during and immediately after the Messinian salinity crisis at the end of the Miocene. The freshwater life-style appeared monophyletic; equating its origin with the salinity crisis resulted in a molecular clock estimate of 1.4% divergence per million years. The last common ancestor probably occupied sandy bottoms and a coastal niche while several species subsequently adapted to new habitats (pelagic, freshwater or stenohaline). The origin of the shallowest clades dated back to the glacial cycling during the Pleistocene epoch.  相似文献   

15.
The use of diverse data sets in phylogenetic studies aiming for understanding evolutionary histories of species can yield conflicting inference. Phylogenetic conflicts observed in animal and plant systems have often been explained by hybridization, incomplete lineage sorting (ILS), or horizontal gene transfer. Here, we used target enrichment data, species tree, and species network approaches to infer the backbone phylogeny of the family Caprifoliaceae, while distinguishing among sources of incongruence. We used 713 nuclear loci and 46 complete plastome sequence data from 43 samples representing 38 species from all major clades to reconstruct the phylogeny of the family using concatenation and coalescence approaches. We found significant nuclear gene tree conflict as well as cytonuclear discordance. Additionally, coalescent simulations and phylogenetic species network analyses suggested putative ancient hybridization among subfamilies of Caprifoliaceae, which seems to be the main source of phylogenetic discordance. Ancestral state reconstruction of six morphological characters revealed some homoplasy for each character examined. By dating the branching events, we inferred the origin of Caprifoliaceae at approximately 66.65 Ma in the late Cretaceous. By integrating evidence from molecular phylogeny, divergence times, and morphology, we here recognize Zabelioideae as a new subfamily in Caprifoliaceae. This work shows the necessity of using a combination of multiple approaches to identify the sources of gene tree discordance. Our study also highlights the importance of using data from both nuclear and plastid genomes to reconstruct deep and shallow phylogenies of plants.  相似文献   

16.
The African brood parasitic finches (Vidua spp.) are host specialists that mimic the songs and nestling mouth markings of their finch hosts (family Estrildidae). Although recent molecular analyses suggest rapid speciation associated with host switches in some members of this group, the association of different Vidua lineages with particular host genera suggests the possibility of cospeciation at higher levels in the host and parasite phylogenies. We compared a phylogeny of all Vidua species with a phylogeny of their estrildid finch hosts and compared divergence time estimates for the two groups. Basal divergences among extant members of the Vidulidae and among Vidua species are more recent than those among host genera and species, respectively, allowing a model of cospeciation to be rejected at most or all levels of the Vidua phylogeny. Nonetheless, some tests for cospeciation indicated significant congruence between host and parasite tree topologies. This result may be an artifact of clade-limited colonization. Host switches in parasitic finches have most often involved new hosts in the same or a closely related genus, an effect that increases the apparent congruence of host and parasites trees.  相似文献   

17.
? Premise of the Study: Little research has been done at the molecular level on the tribe Fumarieae (Papaveraceae). Papaveraceae is a model plant group for studying evolutionary patterns despite the lack of a reference phylogeny for this tribe. We investigated the phylogenetic relationships within the tribe to complete the molecular data for this family in order to help understand its character evolution and biogeographic pattern. ? Methods: We used maximum-parsimony and Bayesian approaches to analyze five DNA regions for 25 species representing 10 of the 11 Fumarieae genera and five outgroups. Evolutionary pathways of four characters (habit, life span, type of fruit, and number of seeds per fruit) were inferred on the phylogeny using parsimony. The ancestral distribution areas were reconstructed using dispersal-vicariance analysis. ? Key Results: Fumarieae is monophyletic and includes three groups that agree with the morphology-based subtribes: Discocapninae, Fumariinae, and Sarcocapninae. Within subtribes, the relationships among genera were different from those obtained with morphological data. Annual life span, nonchasmophytic habit, and a several-seeded capsule were the basal character states for the tribe. The ancestor occupied a continuous area between West Eurasia and Africa. Vicariances explain the divergence between lineages Discocapninae (South Africa) and Fumariinae-Sarcocapninae (Mediterranean), and the disjunction of Fumariinae (Mediterranean-Central Asia). ? Conclusions: Molecular phylogeny confirms the subtribal classification of Fumarieae based on morphology. However it provides different results regarding the relationships among genera within each subtribe, which affects the inference of the evolutionary pathway followed by the four selected characters. The disjunct distribution of the tribe is explained by different vicariance scenarios.  相似文献   

18.
Dipsacales is an asterid angiosperm clade of ca. 1100 species, with most of its lineages occupying temperate regions of the Northern Hemisphere. A recent phylogenetic analysis based on 7593 nucleotides of chloroplast DNA recovered a well-resolved and strongly supported phylogenetic hypothesis, which we use here to estimate divergence times within the group. A molecular clock is strongly rejected, regardless of data partition. We used recently proposed methods that relax the assumption of rate constancy among lineages (local clocks, nonparametric rate smoothing, penalized likelihood, and Bayesian relaxed clock) to estimate the ages of major lineages. Age estimates for Dipsacales varied widely among markers and codon positions, and depended on the fossils used for calibration and method of analysis. Some methods yielded dates for the Dipsacales diversification that appear to be too old (prior to the presumed 125 my [million years] age of eudicots), and others suggested ages that are too young based on well-documented Dipsacales fossils. Concordant penalized likelihood and Bayesian studies imply that Dipsacales originated in the Cretaceous, as did its two major lineages, Adoxaceae and Caprifoliaceae. However, diversification of crown Adoxaceae and Caprifoliaceae mainly occurred in the Tertiary, with the origin of major lineages within these clades mainly occurring during the Eocene. Another round of diversification appears to have occurred in the Miocene. Several radiations, such as Valerianaceae in South America and Dipsacaceae around the Mediterranean, are even more recent. This study demonstrates the wide range of divergence times that can be obtained using different methods and data sets, and cautions against reliance on age estimates based on only a single gene or methodology. Despite this variance, significant conclusions can be made about the timing of Dipsacales evolution.  相似文献   

19.
ABSTRACT: BACKGROUND: The fish family Haemulidae is divided in two subfamilies, Haemulinae and Plectorhynchinae (sweetlips), including approximately 17 genera and 145 species. The family has a broad geographic distribution that encompasses contrasting ecological habitats resulting in a unique potential for evolutionary hypotheses testing. In the present work we have examined the phylogenetic relationships of the family using selected representatives of additional Percomorpha based on Bayesian and Maximum likelihood methods by means of three mitochondrial genes. We also developed a phylogenetic hypothesis of the New World species based on five molecular markers (three mitochondrial and two nuclear) as a framework to evaluate the evolutionary history, the ecological diversification and speciation patterns of this group. RESULTS: Mitochondrial genes and different reconstruction methods consistently recovered a monophyletic Haemulidae with the Sillaginidae as its sister clade (although with low support values). Previous studies proposed different relationships that were not recovered in this analysis. We also present a robust molecular phylogeny of Haemulinae based on the combined data of two nuclear and three mitochondrial genes. All topologies support the monophyly of both sub-families (Haemulinae, Plectorhinchinae). The genus Pomadasys was shown to be polyphyletic and Haemulon, Anisotremus, and Plectorhinchus were found to be paraphyletic. Four of seven presumed geminate pairs were indeed found to be sister species, however our data did not support a contemporaneous divergence. Analyses also revealed that differential use of habitat might have played an important role in the speciation dynamics of this group of fishes, in particular among New World species where extensive sample coverage was available. CONCLUSIONS: This study provides a new hypothesis for the sister clade of Hamulidae and a robust phylogeny of the latter. The presence of para- and polyphyletic genera underscores the need for a taxonomic reassessment within the family. A scarce sampling of the Old World Pomadasys species prevents us to definitively point to a New World origin of the sub-familiy Haemulinae, however our data suggest that this is likely to be the case. This study also illustrates how life history habitat influences speciation and evolutionary trajectories.  相似文献   

20.
Although several investigators have presented data suggesting that the Caprifoliaceae is polyphyletic in origin, the family has been retained as a taxon in recent classifications. Serological analyses of the taxa included within the family have been undertaken to provide additional taxonomic data. Precipitin techniques of double diffusion (Ouchterlony) and nephelometry (Boyden Procedure) were used to analyse serological similarities of seed proteins from representatives of the family. Three distinct groupings were detected for the taxa included in the Caprifoliaceae. AlthoughViburnum exhibited greatest serological similarity withSambucus, Viburnum was quite distinct from all members of the family investigated.Sambucus also was somewhat distinct from the other genera and exhibited about as much serological correspondence withCornus of the Cornaceae as with any tested member of the Caprifoliaceae. The remaining species examined formed a very close serological grouping. These data can be interpreted as supporting either a monophyletic or polyphyletic origin of the family as presently composed, because of the different arrangements of the families Caprifoliaceae and Cornaceae in the various systems of classification.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号