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1.
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The phylogenetic relationships of the African mainland species of the genus Rhampholeon (formerly referred to the genus Brookesia ) with respect to Brookesia superciliaris, Bradypodion pumilus , and the genus Chamaeleo are analysed. Rhampholeon constitutes a genus well separated from Brookesia and may itself be subdivided in two subgroups on the basis of characters derived from the nasal and parietal complexes. A final section investigates problems of cladistic analysis, viz. the relationship of parsimony to character weighting, and pattern versus process as complementary perspectives of character analysis and coding.  相似文献   

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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   

5.
The leaf, stem, root, tuber and dropper anatomy of the orchid tribe Diseae (including the subtribes Satyriinae, Disinae, Brownlecinac, Huttonaeinae and Coryciinae) is reviewed. The study is largely based on investigations of 123 species, and data from several previous publications have also been incorporated. Two characters were identified as being taxonomically valuable: (1) the presence of sclerenchyma caps associated with leaf vascular bundles, and (2) the degree of dissection of the siphonostele of the tuber (‘polystelic’ or ‘monostelic’). The phylogenetic analysis shows that anatomical characters do not change the basic structure of a cladogram that is based on morphological characters. The taxa of Diseae are discussed on the basis of anatomical data. Subtribes Satyriinae (excluding the anatomically unusual genus Pachites), Brownleeinae, Huttonaeinae, and Coryciinae are uniform in. critical anatomical characters. However, subtribe Disinae is rather diverse in vegetative anatomy. Disa sect. Micranthae differs from the rest of the genus in its leaf anatomy. The occurrence of foliar sclerenchyma bundle caps and ‘polystelic’ tubers supports the incorporation of Herschelianthe in Disa sect. Stenocarpa.  相似文献   

6.
Cladistic analysis of extant mustelids based on a data matrix consisting of 30 characters derived from morphological study of the head skeleton in all 23 genera, and 16 characters gleaned from the literature, yielded 75 most parsimonious trees with a consistency index of 0.487 using PAUP 3.0s. The analysis strongly supports the monophyly of both the Mephitinae (skunks) and Lutrinae (otters). The Mustelinae (weasels, martens, wolverine, etc) is probably paraphyletic, but there is some support for a monophyletic group consisting of the mustelines and the honey badger Mellivora. The Melinae (badgers) is a polyphyletic group; the badger ecomorph probably evolved independently at least three times within the Mustelidae. On consensus trees, there is a lack of resolution concerning the relationships within the Mephitinae and Lutrinae and the positions of Galictis and Mustela. These results are broadly congruent with a cladistic interpretation of Simpson's intent in his influential 1945 classification. Thus, a paraphyletic Mustelinae is consistent with Simpson's conception of a horizontal grouping, whereas the Mephitinae and Lutrinae represent vertical divergent lineages. In contrast, the cladistic status of the Melinae is not consistent with Simpsonian classificatory principles. The status of the monotypic Mellivorinae cannot be evaluated without considering its putative fossil members; however, the clustering of Mellivora with the badger Taxidea is not consistent with Simpson's scheme. Some of the more inclusive clades in the most parsimonious trees are vulnerable to minor changes to the data matrix. The fossil record is consistent with the basic outlines of the cladistic pattern and explains various ostensible biogeographic anomalies. Bootstrap analysis identified marked variation in the support for the components of the cladistic pattern.  相似文献   

7.
The early Tertiary (Paleocene and Eocene) family Presbyornithidae is one of the most completely known group of fossil birds. Essentially all parts of the skeleton are represented in the fossil record, allowing a thorough analysis of the phylogenetic position of the family. Forty-two families of nonpasserine birds representing the orders Ciconiiformes, Anseriformes, Galliformes, Gruiformes and Charadriiformes, were included in a cladistic analysis of 71 skeletal characters. The previously suggested anseriform affinity of the Presbyornithidae was confirmed. Furthermore, the family proved to be closer to the Anatidae than to the Anhimidae or Anseranatidae. The many postcranial similarities with certain charadriiform birds as the Burhinidae, obviously are plesiomorphies. By this observation, a better undestanding of character evolution in nonpasserine skeletal morphology is gained. The often suggested close relationship of anseriform and galliform birds is not confirmed by osteology. Instead, the Anseriformes and the Phoenicopteridae form a monophyletic clade that is the sister to the remaining ciconiiform birds. This result renders the Ciconiiformes sensu Wetmore (1960) polyphyletic.  相似文献   

8.
The leaf, stem, root, tuber and dropper anatomy of the orchid tribe Diseae (including the subtribes Satyriinae, Disinae, Brownlecinac, Huttonaeinae and Coryciinae) is reviewed. The study is largely based on investigations of 123 species, and data from several previous publications have also been incorporated. Two characters were identified as being taxonomically valuable: (1) the presence of sclerenchyma caps associated with leaf vascular bundles, and (2) the degree of dissection of the siphonostele of the tuber ('polystelic' or 'monostelic'). The phylogenetic analysis shows that anatomical characters do not change the basic structure of a cladogram that is based on morphological characters. The taxa of Diseae are discussed on the basis of anatomical data. Subtribes Satyriinae (excluding the anatomically unusual genus Pachites), Brownleeinae, Huttonaeinae, and Coryciinae are uniform in. critical anatomical characters. However, subtribe Disinae is rather diverse in vegetative anatomy. Disa sect. Micranthae differs from the rest of the genus in its leaf anatomy. The occurrence of foliar sclerenchyma bundle caps and 'polystelic' tubers supports the incorporation of Herschelianthe in Disa sect. Stenocarpa.  相似文献   

9.
A cladistic analysis of the genusAnisopappus (Asteraceae: Inuleae) has been undertaken. A hypothesis of species interrelationships in the genus is presented for the first time. The analysis also includedArctotis (Arctoteae), used as outgroup, and five additional genera from theInuleae: Geigeria, Calostephane, Asteriscus, Buphthalmum, Pulicaria, andInula. It is concluded thatAnisopappus is a monophyletic group situated at the base of the tribe, diagnosed by, e.g., their obtuse stylar sweeping-hairs. The species with acute sweeping-hairs were found to be derived within the genus. Problems concerning species delimitation, biogeography and character evolution in the genus are briefly discussed.  相似文献   

10.
西藏野生油菜性状演化与分支分类研究   总被引:1,自引:0,他引:1  
以西藏野生白菜型油菜(Brassica campestris L.)和野生芥菜型油菜(B.juncea Czern.et Coss.)的39个形态学性状为依据,以醉蝶花(Cleome spinosa Jacq.)为外类群,确定了性状的祖征和衍征。应用最大同步法,对35个西藏野生油菜种源的性状演化与分支分类进行了研究。结果表明,野生白菜型油菜和野生芥菜型油菜的基生叶、薹茎叶和花器官性状既有同期演化性状也有非同期演化性状;而伸长茎叶的所有性状均为非同期演化性状,有各自独特的演化规则。西藏野生白菜型油菜分为藏东野生白菜型油菜和藏中野生白菜型油菜2个组,野生芥菜型油菜分为藏中西野生芥菜型油菜和藏南野生芥菜型油菜2个组,各自沿不同的路线演化。  相似文献   

11.
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   

12.
Abstract. The Philanthinae, as treated here, contains the eight valid genera Aphilanthops Patton, Cerceris Latreille, Clypeadon Patton, Eucerceris Cresson, Philanthinus Beaumont, Philanthus Fabricius, Pseudoscolia Radoszkowski and Trachypus Klug. Listropygia Bohart is synonymized with Clypeadon , syn.n. The genera Eremiasphecium Kohl and Odontosphex Arnold are removed from the Philanthinae and regarded as genera incertae sedis within Sphecidae. Analysis of the genera of this redefined subfamily Philanthinae finds two major clades whose monophyly is strongly supported: ( Philanthinus + ( Philanthus + Trachypus )) [= Tribe Philanthini] and ( Pseudoscolia + ( Cerceris + Eucerceris )) [= Tribe Cercerini]. There is some evidence for the monophyly of Clypeadon + Aphilanthops [= Tribe Aphilanthopini]. Cerceris and Philanthus are inferred to be paraphyletic with respect to Eucerceris and Trachypus , respectively. Philanthinus is removed from the tribe Aphilanthopini and placed in the tribe Philanthini, and the monotypic tribe Pseudoscoliini is synonymized with Cercerini.  相似文献   

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A morphologically based cladistic analysis of 40 genera included within the Trichostrongyloidea (Amidostomatidae, Dromaeostrongylidae and Trichostrongylidae) is proposed. Two genera were used as outgroups, one from the Strongylina and the other from the Ancylostomatina. Seven genera do not appear in the matrix because some significant morphological characters remain unknown for these genera. Nonetheless, except for Moguranema which is excluded as incertae sedis, a likely systematic position could be assigned to them based on the morphological characters that are known. The classification which best fits the consensus tree is composed of three families. In adding the genera not included in the tree, we obtain: (i) Trichostrongylidae with three sub-families, Amidostomatinae (four genera), Filarinematinae (three genera) and Trichostrongylinae (five genera); (ii) Haemonchidae with two sub-families: Ostertagiinae (eight genera) and Haemonchinae (five genera); (iii) Cooperiidae with three sub-families: Libyostrongylinae (five genera), Obeliscoidinae n. subfam. (five genera) and Cooperiinae (ten genera). Dromaeostrongylus and Ortleppstrongylus, whose females have a caudal spine, are excluded from the Trichostrongyloidea and are placed in the Molineoidea. The hypotheses relating to the evolutionary history of the Trichostrongyloidea are: the origin of the superfamily could have occurred during the upper Cretaceous period. The two most ancient sub-families (Amidostomatinae and Filarinematinae) would be of Gwondwanan origin and evolved during the Paleocene period within Neotropical aquatic birds and within the Australian marsupials. The Trichostrongylinae would have arisen during the Eocene period within birds and then adapted to diverse archaic mammals in the Neotropical region on one hand and in the Nearctic region, on the other hand and lastly adapted to the Lagomorpha and subsequently to the Ruminantia. In both families originating from the Trichostrongylidae, the adaptation to the Lagomorpha may have taken place during the Oligocene but in a different way. In the Haemonchidae, the Ostertagiinae may have passed directly from the Neartic region to Europe. In the Cooperiidae, the adaptation to Lagomorpha may have occurred either within the Libyostrongylinae which may have remained in the Ethiopian region since the Paleocene, or, more likely, by the passage of the Obeliscoidinae from the Nearctic region to the Asian, through the Bering strait. In all cases, the adaptation of the Trichostrongyloidea of Lagomorpha to Ruminants apparently took place during the Miocene, mainly in the Palearctic and the Ethiopian regions.  相似文献   

15.
The dental and cranial morphologies of all species ofSaguinus, S. oedipus, S. geoffroyi, S. leucopus, S. nigricollis, S. fuscicollis, S. labiatus, S. mystax, S. imperator, S. bicolor, andS. midas are examined. The following hypotheses are developed by cladistic methodology, using only synapomorphic characters to assess the interspecific relationships ofSaguinus.Saguinus are divided into two main groups; one consists ofS. oedipus, S. geoffroyi, andS. leucopus, and the other includesS. inustus, S. nigricollis, S. fuscicollis, S. labiatus, S. mystax, S. imperator, S. bicolor, andS. midas. In the former group,S. oedipus is more closely related toS. geoffroyi than either is toS. leucopus. In the latter group,S. labiatus, S. mystax, andS. imperator are classified into one group, andS. bicolor andS. midas form one monophyletic group.  相似文献   

16.
Abstract The first synopsis of Mesozoic weevils (Curculionoidea: Coleoptera) is presented. Changes of family, genera and species abundance during the Mesozoic revealed three distributional patterns. The Jurassic (Karatau) fauna was dominated by the Nemonychidae. During the Early Cretaceous (beginning at the Jurassic/Cretaceous border), the Ithyceridae was the prevalent group with a significant role played by the Nemonychidae. In the Late Cretaceous (Cenomanian and Turonian), the major groups were the Curculionidae and Brentidae. Obviously, the change of weevil fauna during this period was due to the expansion of the angiosperms, which provided multiple niches in their vegetative and reproductive organs for weevil development.  相似文献   

17.
The phylogeny of the Vitrinidae is reconstructed in a cladistic analysis based on characters of the genitalia, the copulation behaviour and the radula. The genera with an atrial stimulator turned out to be the earliest branches of the Vitrinidae, whereas the genera with a glandula amatoria form a monophyletic, taxonomically apomorphic group. The differences between the proposed phylogeny and previous hypotheses are discussed. The ancestral areas of the Vitrinidae and its sister group, the limacoid slugs Boettgerillidae–Limacidae–Agriolimacidae, are estimated using weighted ancestral area analysis. The Vitrinidae and the limacoid slugs might have originated by a vicariance event between Central Europe and the Near East. © 2002 The Linnean Society of London. Zoological Journal of the Linnean Society , 2002, 134 , 347–358.  相似文献   

18.
五味子属(五味子科)分类系统的初步修订   总被引:3,自引:2,他引:3  
林祁  杨志荣 《植物研究》2007,27(1):6-15
通过对前人提出的五味子属(五味子科)分类系统的点评,根据五味子属植物的33个形态性状及其性状分析,经过分支分析,提出一个新的五味子属分类系统:将五味子属分为五味子亚属和团蕊五味子亚属;将五味子亚属分为多蕊五味子组、少蕊五味子组、中华五味子组和五味子组。编排了分亚属、组和种的检索表,对每个种上分类等级均列出其模式、异名和代表种。  相似文献   

19.
Among abiotic molecules available in primitive environments, free amino acids are good candidates as the first source of energy and molecules for early protocells. Amino acid catabolic pathways are likely to be one of the very first metabolic pathways of life. Among them, which ones were the first to emerge? A cladistic analysis of catabolic pathways of the sixteen aliphatic amino acids and two portions of the Krebs cycle is performed using four criteria of homology. The cladogram shows that the earliest pathways to emerge are not portions of the Krebs cycle but catabolisms of aspartate, asparagine, glutamate, glutamine, proline, arginine. Earliest enzymatic catabolic functions were deaminations and transaminations. Later on appeared enzymatic decarboxylations. The consensus tree allows to propose four time spans for catabolism development and corroborates the views of Cordón in 1990 about the evolution of catabolism.  相似文献   

20.
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