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1.
Abstract. This study compares the results of Rozen's cladistic analysis of the larvae of fifteen genera of cleptoparasitic bees in the subfamily Nomadinae with an independent data set of adult characters for the same genera. Adult characters exhibited considerably higher levels of homoplasy and poorer resolution of cladistic relationships, with multiple equally parsimonious cladograms. However, comparison of a Nelson consensus tree based on adult characters with the cladogram based on larval characters reveals three components consistently supported in both analyses (the tribes Epeolini and Ammobatini, and Neopasites + Neolarra) , one component supported only by adult characters (Isepeolus + Protepeolus) , and one terminal component supported only by larval characters (Nomada + Ammobatini), as well as several more inclusive groupings based on larval characters that are difficult to compare with the adult consensus tree because it shows so much less resolution. When adult and larval characters are combined in a single data matrix, the resulting cladogram closely resembles the cladogram based on larval characters alone, although levels of homoplasy are considerably higher than in the larval analysis.
A preliminary analysis of adult characters for thirty-four genera in the Nomadinae also exhibited high levels of homoplasy and very large numbers of equally parsimonious cladograms. Nevertheless, certain consistent monophyletic groupings, most notably the Epeolini and Ammobatini, were also supported in this analysis. The one currently recognized tribe whose monophyly has received no support from any analysis is the Nomadini.
The relevance of these phylogenetic hypotheses to our understanding of host associations and variable features of egg morphology and oviposition behaviour in nomadine bees is briefly discussed.  相似文献   

2.
The first cladistic analysis of phylogeny in the class Scaphopoda (Steiner 1992a,1996) examined relationships among family and selected sub-family taxa using morphological data. A preferred/ consensus tree of relationships illustrated monophyly of the orders Dentaliida and Gadilida, partial resolution among dentaliid families, and complete resolution among gadilid taxa. However, several alternative replications of the analysis, including use of a revised data matrix, did not produce the reported tree number or level of resolution; in all cases, monophyly of the Dentaliida was not supported by strict consensus of resultant parsimonious trees. Reanalysis, using unordered characters and outgroup rooting, only clearly resolves monophyly of the Gadilida and the sister relationship of the Entalinidae with the remaining gadilid families. These analyses emphasize the need for more comparative data and thorough parsimony analysis in scaphopod cladistic phylogenetics, as relationships in this class are still some way from resolution.  相似文献   

3.
ON CONSENSUS, COLLAPSIBILITY, AND CLADE CONCORDANCE   总被引:1,自引:0,他引:1  
Abstract — Consensus in cladistics is reviewed. Consensus trees, which summarize the agreement in grouping among a set of cladograms, are distinguished from compromise trees, which may contain groups that do not appear in all the cladograms being compared. Only a strict or Nelson tree is an actual consensus. This distinction has implications for the concept of support for cladograms: only those branches supported under all possible optimizations are unambiguously supported. We refer to such cladograms as strictly supported, in contrast to the semistrictly (ambiguously) supported cladograms output by various current microcomputer programs for cladistic analysis. Such semistrictly supported cladograms may be collapsed, however, by a variety of options in various programs. Consideration of collapsibility and optimization on multifurcations leads to some conclusions on the use of consensus. Consensus tree length provides information about character conflict that occurs between, not within, cladograms. We propose the clade concordance index, which employs the consensus tree length to measure inter-cladogram character conflict for all characters among a set of cladograms.  相似文献   

4.
The family of polygyrid land snails in North America is significant for its sympatric shell convergences, diversity of mating systems and complex zoogeography; its monophyly and its relation to other families has long been questionable. Cladistic analysis has been performed on one representative each of 17 subfamilies, including all three polygyrid subfamilies and one or more subfamilies each from all ten of the families that have been proposed as the polygyrid sister groups. Eighteen anatomical synapomorphies are used, of which eight are newly discovered, four are differently assessed from previous studies, and six are traditional. The resulting strict consensus tree of alternative maximum-parsimony cladograms is: (Acavidae (Ammonitellidae Corillidae ((Discidae Oreohelicidae) (Helminthoglyptidae Bradybaenidae Polygyridae (Thysanophoridae (Camaenidae Sagdidae)))))).
According to this working hypothesis, the Polygyridae are monophyletic, and their sister group remains unresolved, although the Acavidae, Ammonitellidae, Corillidae, Discidae and Oreohelicidae can be ruled out. Of the five classifications of stylommatophoran families that have been proposed in the past 12 years, the consensus tree is closest to that of Nordsieck. For future morphological work, three regions are recommended as potentially rich in unused phylogenetic information: the fertilization pouch-seminal receptacle complex, the ureter at the pneumostome and the ventral-chain ganglia. Simultaneous dissection, wkh side-by-side comparisons, is recommended over other methods for detecting homologies in land snails. Molecular characters should be exploited, because of the scarcity and the frequent homoplasy of morphological characters.  相似文献   

5.
The phylogeny of the families of Culicomorpha and their closest relatives are cladistically reinvestigated adding published information from several sources. A revised data matrix is presented and some characters are discussed. Different outgroups and options used, characters unordered or ordered, the results reweighted or not and the results discussed. Nymphomyiidae in all cladograms, alone or together with Thaumaleidae, forms the sister group of the traditional Culicomorpha and should be included in this infraorder as suggested by others. Superfamily Chironomoidea is not monophyletic as Thaumaleidae or Nymphomyiidae + Thaumaleidae form the sister group to the remaining traditional Culicomorpha. The mutual relationships of Chironomidae, Simuliidae and Ceratopogonidae are variable between cladograms. They form a monophyletic group with Chironomidae and Simuliidae as sister groups when characters are unordered and reweighted or when some characters are ordered, others unordered and the result reweighted. When the characters are ordered, or when a combination of ordered and unordered are used they form a Hennigian comb with the phyletic sequence Chironomidae/Ceratopogonidae/Simuliidae. When characters are ordered and reweighted the phyletic sequence is Chironomidae/Simuliidae/Ceratopogonidae. Culicoidea is monophyletic in all cladograms, but the division into superfamilies is not warranted.  相似文献   

6.
Abstract  Numerical cladistic method was used for analyzing the phylogeny of ladybirds, based upon adult and larval characters. The analysis of adult characters for 21 tribes, representing all subfamilies proposed by various authors, exhibited 18 equally parsimonious cladograms with high level of homoplasy. Five lineages were roughly revealed in the strict consensus tree: Sticholotidinae, Epilachninae, Coccinellinae (including Singhikalini), Coccidulinae (excluding Noviini) and Scymninae+Chilocorinae. The taxonomic interpretation of the adult analysis was similar to the classification proposed by Chazeauet al . (1990). Comparison of a preliminary analysis based on the larval characters for 14 tribes revealed only one component consistently supported in both analyses (Serangiini+Sukunahikonini). Larval analysis showed that Epi-lachinae is the most primitive and highly derived group of the Coccinellidae. Larval characters might be more satisfactory in revealing the phylogeny.  相似文献   

7.
根据成虫和幼虫的特征,应用数值支序方法探讨瓢虫科的系统发育.基于中国21族(包括不同学者提出的所有亚科)36个成虫性状,计算得到18个具有高度同质(homoplasy)的最简约的支序图.共同树显示5个支系:小艳瓢虫亚科,食植瓢虫亚科,瓢虫亚科(包括粗毛瓢虫族Singhikalini);红瓢虫亚科(不包括短角瓢虫族),以及小毛瓢虫亚科+盔唇瓢虫亚科(包括短角瓢虫族).这与Chazeau等(1990)提出的分六亚科系统相似.对14族幼虫18个性状初步分析,结果与相同14族成虫分析比较,只有一个组分即刀角瓢虫族和展唇瓢虫族的亲缘关系在两个分析中得到一致的支持.食植瓢虫是瓢虫科中最原始但高度衍化的一族.在揭示系统发育上,幼虫的研究或许更令人满意.  相似文献   

8.
A cladistic analysis of Lophopidae was performed, using 73 observed morphological characters and 41 taxa. This analysis involved 36 genera belonging to the Lophopidae family and 5 outgroups. For a better understanding of the selected characters some illustrations are provided. The most parsimonious cladograms obtained show that the Lophopidae cannot be considered as a monophyletic lineage unless two genera are withdrawn from this family: Hesticus Walker, 1862, and Silvanana Metcalf, 1947. The systematic position of these two genera remains uncertain. They cannot yet be included in another family of Fulgoromorpha. A cladistic analysis of each of the 19 remaining Fulgoromorphan families must be performed first. A new family could be created for these two genera, but not before we are sure that these two genera are in no way members of an existing family. The outgroup problem is discussed. The monophyletic lineage represented by the Lophopidae can be divided into four natural groups: Carriona+, Makota+, Sarebasa+, and Bisma+. When a cladistic analysis is completed using a data matrix without characters linked to females, the cladogram obtained presents a disrupted basal resolution. Female characters appear to bring a phylogenetic signal important basally in the evolution of the Lophopidae but also apically, directly between the relationships of some genera. A similar analysis, using a matrix without characters linked to males, provides a phylogeny disrupted between the groups that form the Lophopidae and in the basal resolution in these groups. The respective impacts of the genitalic characters are discussed in relation to sexual selection conflict.  相似文献   

9.
A phylogenetic analysis of Neuroptera using thirty‐six predominantly morphological characters of adults and larvae is presented. This is the first computerized cladistic analysis at the ordinal level. It included nineteen species representing seventeen families of Neuroptera, three species representing two families (Sialidae and both subfamilies of Corydalidae) of Megaloptera, two species representing two families of Raphidioptera and as prime outgroup one species of a family of Coleoptera. Ten equally most parsimonious cladograms were found, of which one is selected and presented in detail. The results are discussed in light of recent results from mental phylogenetic cladograms. The suborders Nevrorthi‐ formia, Myrmeleontiformia and Hemerobiiformia received strong support, however Nevrorthiformia formed the adelphotaxon of Myrmeleontiformia + Hemerobiiformia (former sister group of Myrmeleontiformia only). In Myrmeleontiformia, the sister‐group relationships between Psychopsidae + Nemopteridae and Nymphidae + (Myrmeleontidae + Ascalaphidae) are corroborated. In Hemerobiiformia, Ithonidae + Polystoechotidae is confirmed as the sister group of the remaining families. Dilaridae + (Mantispidae + (Rhachiberothidae + Berothidae)), which has already been proposed, is confirmed. Chrysopidae + Osmylidae emerged as the sister group of a clade comprising Hemerobiidae + ((Coniopterygidae + Sisyridae) + (dilarid clade)). Despite the sister‐group relationship of Coniopterygidae + Sisyridae being only weakly supported, the position of Coniopterygidae within the higher Hemerobiiformia is corroborated. At the ordinal level, the analysis provided clear support for the hypothesis that Megaloptera + Neuroptera are sister groups, which upsets the conventional Megaloptera + Raphidioptera hypothesis.  相似文献   

10.
柳属的分支系统学分析   总被引:1,自引:0,他引:1  
基于61个广义的形态学性状,以杨属为外类群对柳属进行了分支系统学分析.经简约性分析,得到了21个同等简约的分支树,其严格一致树支持柳属为一个自然的分类群,但不支持将钻天柳属和心叶柳属从柳属中划分出去独立成属,也不支持对柳属进行属级水平上的细分,后两个结果得到孢粉学和分子系统学研究的支持.柳亚属为一个单系分支,皱纹柳亚属和黄花柳亚属也形成了一个单系分支.根据本研究的结果,建议将柳属划分为钻天柳亚属、柳亚属及黄花柳亚属3个亚属.由于较低的靴带支持率,其系统发育关系难于探讨.鉴于分支分析的一致性指数、保持性指数、各分支内部的支持率均不高,柳属的属下分类系统的划分有待进一步的研究.  相似文献   

11.
A cladistic study ofDipsacaceae (Asteridae, Dipsacales) was undertaken, based mainly on morphological and palynological characters, obtained by investigations of herbarium material and from the literature. Outgroups includedMorinaceae, Triplostegiaceae, and a subset ofValerianaceae. The consensus tree resulting from three equally parsimonious cladograms shows thatDipsacaceae are divided into two major clades, one withDipsacus andCephalaria, the other including the remaining genera. Within the latter clade,Knautia is the sister group of the rest of the taxa. This study is a reappraisal ofDipsacaceae phylogeny, and the results broadly match previous evidence.  相似文献   

12.
13.
The basis for a preliminary analysis of the relationships within the monophyletic Diphyllidea is outlined. Information on morphological characters and their interpretation within a phylogenetic context are presented. A cladistic analysis at the species level was conducted based on a matrix of 21 morphological characters. Character polarity was determined by taxonomic outgroup analysis relative to the basal orders, Pseudophyllidea and Haplobothriidea. The phylogeny for the diphyllideans was found to be poorly resolved based on characters currently available for evaluation. Computer assisted cladistic analysis found three equally parsimonious trees with a consistency index of 0.54. The topology of these trees shows that Ditrachybothridium macrocephalum is the basal taxon and the putative sister group for species of Echinobothrium; Macrobothridium rhynchobati is grouped among species of Echinobothrium. If the classification is to be consistent with this tree, M. rhynchobati should be included in the genus Echinobothrium. This observation should be carefully examined, considering the relative paucity of useful morphological characters currently available for this group.  相似文献   

14.
A molecular systematic study of Scrophulariaceae sensu lato using DNA sequences of three plastid genes (rbcL, ndhF, and rps2) revealed at least five distinct monophyletic groups. Thirty-nine genera representing 24 tribes of the Scrophulariaceae s.l. (sensu lato) were analyzed along with representatives of 15 other families of Lamiales. The Scrophulariaceae s.s. (sensu stricto) include part or all of tribes Aptosimeae, Hemimerideae, Leucophylleae, Manuleae, Selagineae, and Verbasceae (= Scrophularieae) and the conventional families Buddlejaceae and Myoporaceae. Veronicaceae includes all or part of tribes Angelonieae, Antirrhineae, Cheloneae, Digitaleae, and Gratioleae and the conventional families Callitrichaceae, Globulariaceae, Hippuridaceae, and Plantaginaceae. The Orobanchaceae include tribes Buchnereae, Rhinantheae, and the conventional Orobanchaceae. All sampled members of Orobanchaceae are parasitic, except Lindenbergia, which is sister to the rest of the family. Family Calceolariaceae Olmstead is newly erected herein to recognize the phylogenetic distinctiveness of tribe Calceolarieae. The Calceolariaceae are close to the base of the Lamiales. The Stilbaceae are expanded by the inclusion of Halleria. Mimulus does not belong in any of these five groups.  相似文献   

15.
Phylogenetic relationships among families of the Scaphopoda (Mollusca)   总被引:1,自引:0,他引:1  
Phylogenetic relationships among families in the molluscan class Scaphopoda were analysed using morphological characters and cladistic parsimony methods. A maximum parsimony analysis of 34 discrete characters, treated as unordered and equally weighted, from nine ingroup terminal taxa produced a single most parsimonious tree; supplementary analyses of tree length frequency distribution and Bremer support indices indicate a strong phylogenetic signal from the data and moderate to minimally supported clades. The traditional major division of the class, the orders Dentaliida and Gadilida, is supported as both taxa are confirmed as monophyletic clades. Within the Dentaliida, two clades are recognized, the first comprised of the families Dentaliidae and Fustiariidae, the second of the Rhabdidae and Calliodentaliidae; together, these groups comprise a third clade, which has the Gadilinidae as sister. Within the Gadilida, a nested series of relationships is found among [Entalinidae, [Pulsellidae, [Wemersoniellidae, Gadilidae]]]. These results lend cladistic support to earlier hypotheses of shared common ancestry for some families, but are at variance with other previous hypotheses of evolution in the Scaphopoda. Furthermore, analysis of constituent Gadilinidae representatives provide evidence for paraphyly of this family. The relationships supported here provide a working hypothesis that the development of new characters and greater breadth of taxonomic sampling can test, with a suggested primary goal of establishing monophyly at the family level.  相似文献   

16.
Lopezia, a genus of 22 species largely restricted to Mexico, forms a monophyletic group defined by the possession of two stamens in tetramerous flowerS. A cladistic analysis of the genus was performed using 16 characters from morphology, anatomy and embryology. Twenty of the 22 species were considered the terminal taxa. Polarity of the characters was based on the outgroup comparison method, using three alternative outgroups: the genus Fuchsia, Onagraceae excluding Ludwigia, and Epilobieae-Onagreae. Using Fuchsia as outgroup, 29 equally parsimonious cladograms were produced, each with 24 steps and a consistency index of 0.75. A successive weighting procedure was applied, resulting in 15 cladograms with consistency index of 0.85. The strict consensus cladogram defines eight monophyletic groups and supports most of the current sectional classification of Lopezia, with the exception that no synapomorphy defines section Jehlia. The larger sections Lopezia and Pelozia, although well-defined as clades, are not fully resolved internally. All cladograms support section Riesenbachia as monophyletic. The two alternative hypotheses for outgroups produced similar results: 61 most parsimonious trees, reduced after the successive weighting procedure to 15, which are identical to those produced with Fuchsia as outgroup. These results are discussed in the context of data on cytology and pollination biology.  相似文献   

17.
Abstract.  A two-stage cladistic analysis of 114 characters from adult and immature stage morphology provided phylogenetic hypotheses for the diverse Neotropical nymphalid butterfly genus Adelpha Hübner. Higher-level cladistic relationships were inferred for thirty Adelpha species and twenty other species of Limenitidini, confirming the monophyly of Adelpha as currently conceived and indicating several montane Asian species as potential sister taxa for the genus. Cladistic relationships between all eighty-five Adelpha species were then inferred using three outgroup combinations. Basal and terminal nodes were reasonably resolved and supported, but a low proportion of non-wing pattern characters resulted in weak resolution and support in the middle of the tree. The most basal members of Adelpha feed on the temperate or montane plant family Caprifoliaceae, suggesting that a switch from this family early in the evolutionary history was important in subsequent diversification into tropical lowland habitats. The cladograms confirm suspicions of earlier authors that dorsal mimetic wing patterns have convergently evolved a number of times in Adelpha . The subtribal classification of Limenitidini is discussed and both Lebadea (from Parthenina) and Neptina are transferred to Limenitidina, whereas Cymothoe , Bhagadatta and Pseudoneptis (all formerly Limenitidina) are regarded as incertae sedis .  相似文献   

18.
Ichneumonoid phylogeny is revised on the basis of morphological, palaeontological and molecular evidence. The only previous formal cladistic study of the phylogeny of the families of the superfamily Ichneumonoidea made many assumptions about what families lower taxa belonged to and was based on a very limited set of characters, nearly all of which were uninformative at family level. We have subdivided both Ichneumonidae and Braconidae into major groups, investigated several new character systems, reinterpreted some characters, scored several character states for extinct taxa by examining impression fossils using environment chamber scanning electron microscopy, and included data for a significant new subfamily of Braconidae from Cretaceous amber of New Jersey. Sixteen different variants of the data set were each subjected to parsimony analysis without weighting and with successive approximations weighting employing both maximum and minimum values of both the retention and rescaled consistency indices. Each analysis resulted in one of seven different strict consensus trees. Consensus trees based on subsets of these trees, selected on the basis of the optimal character compatibility index (OCCI), resulted in an eighth distinct tree. All trees had the Braconidae monophyletic with the Trachypetinae as the basal clade, and also had a clade comprising various arrangements of Apozyginae, the Rhyssalinae group, Aphidiinae and 'other cyclostomes', but relationships among the remaining braconid groups varied between trees. Only one of the consensus trees had the Ichneumonidae (including Tanychorella ) monophyletic. The Eoichneumonidae + Tanychora are the sister group the Braconidae in two of the consensus trees. Paxylommatinae were basal in the clade comprising the Eoichneumonidae + Tanychora and the Braconidae. The preferred tree, based on the highest OCCI was used for interpreting character state transitions.  相似文献   

19.
MAJOR CLADES OF THE ANGIOSPERMS   总被引:2,自引:0,他引:2  
Abstract— Our knowledge of fundamental angiosperm interrelationships is still very incomplete. The absence of a narrowly circumscribed gymnosperm outgroup, ideally the sister group, makes character evaluation, necessary for a cladistic analysis, difficult. According to current views the superorder Magnoliiflorae with a number of other groups, for example the monocotyledons, may represent a complex of families near the base of the angiosperms. Interrelationships of groups within the monocotyledons are much better understood than those between groups within the dicotyledons. A cladogram of monocotyledon orders based on earlier work by R. Dahlgren, H. T. Clifford, and F. N. Rasmussen is presented. A data matrix for a sample of the angiosperms with 61 characters for 49 taxa, mostly magnoliifloran and related families, is presented. The characters are polarized mainly according to the current view that the primitive angiosperm morphotype is a woody dicotyledon with strobiloid flowers. As an alternative the matrix is adjusted following W. C. Burger's conjecture that the primitive angiosperm was a herbaceous monocotyledon with trimerous flowers. Both matrices were run in a computerized parsimony analysis, resulting in numerous equally parsimonious solutions. This result is illustrative of the great homoplasy in the available character information, and also of how little actually is known about fundamental angiosperm interrelationships or phylogeny.  相似文献   

20.
通过对中国化石骨舌鱼类及骨舌鱼类现生主要类群的比较研究,用 PAUP 软件对31个分类单元的65个特征进行了分析,得到了16个最简约的分支图(步长为206,一致性指数为 0.4320,保留指数为0.7194)。严格合意树显示,中国早白垩世的骨舌鱼类(酒泉鱼、狼鳍鱼、固阳鱼、吉南鱼、同心鱼、西夏鱼、昆都仑鱼和华夏鱼)主要为骨舌鱼超目中不同等级的干群;与一般的观点不同,始舌齿鱼与蛟河鱼组成了姊妹群关系;骨舌鱼目由 Thaumaturus、弓背鱼亚目和骨舌鱼亚目组成;弓背鱼类与象鼻鱼类关系更近;Ostariostoma 为弓背鱼科的姊妹群;副狼鳍鱼与[骨舌鱼亚科+犁齿鱼亚科]组成了姊妹群,该姊妹群关系的建立,将骨舌鱼科的历史延伸到了早白垩世。  相似文献   

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