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1.
鹅观草属的系统发育分析   总被引:2,自引:0,他引:2  
蔡联炳  王玉金 《植物研究》2001,21(4):554-560
根据分支系统学的原理和方法, 对禾本科鹅观草属进行了系统发育分析。鹅观草属传统分类上的18 个系被确定为终端类群, 来自形态学、解剖学、细胞学和孢粉学的23 个性状被选作建立矩阵的依据;雀麦族中的短柄草属作为外类群被用于外部性状的极性识别, 过去分析过的性状资料被用于微观特征的极性判断;采用PAUP 程序对矩阵进行运算, 共获得6 个同等简约的谱系分支图, 其中具最低f-比值的图被选作分支分析的基础。结果表明, 分支图上显示的组、系划分与传统分类的基本一致, 各类群间的演化关系与过去凭借单一证据所作的零散推断也基本吻合。所不同的是半颖组各支类群不是共祖起源, 可能具有复杂的内部组成;在个别系间, 分支图展现的类群位置与宏观分析的存在差异。  相似文献   

2.
Phylogenetic relationships among members of the family Belidae (Curculionoidea) were reconstructed through cladistic analysis using 58 characters and 17 terminals. The characters were from larval morphology (30), adult morphology (25) and biology regarding larval host-plants and feeding habits (three). They were scored for exemplar taxa in 17 genera, representing different belid subfamilies and tribes, plus two outgroup taxa in Megalopodidae and Nemonychidae. The sampled genera included all those for which larval and adult information is available, and two known only from adults. New information on the larvae and biology of two oxycorynines is provided. These are the Chilean Oxycraspedus cribricollis , whose larvae live in decayed female strobili of the gymnosperm Araucaria araucana , and Hydnorobius hydnorae from Argentina, whose larvae, described and illustrated in the present paper, develop inside the flower and fruit bodies of Prosopanche americana (Hydnoraceae), a root-parasitic angiosperm. The relationships proposed by the single optimal cladogram resulting from simultaneous analysis of all taxa and characters are recovered by one of three optimal cladograms based on the larval data set alone. The cladogram justifies a revised classification of Belidae in two sister subfamilies: Belinae (with tribes Pachyurini, Agnesiotidini and Belini) and Oxycoryninae (with tribes Oxycorynini and Aglycyderini). It summarizes larval and adult synapomorphies defining the family Belidae, subfamilies and tribes. Based on the phylogenetic tree, the evolution of biological traits is traced. Larval development in vegetative organs of conifers is ancestral in Belidae. A shift to reproductive structures characterizes the Oxycorynini, a habit which was conserved while several shifts to distantly related host-plant groups occurred.  相似文献   

3.
The genus Leptodactylus is predominantly Neotropical (a few species have colonized the southern Neartic region) and is distributed from Texas to Argentina and on certain Caribbean islands. Leptodactylus was divided into five groups of species: Leptodactylus melanonotus , Leptodactylus ocellatus, Leptodactylus fuscus , Leptodactylus pentadactylus and Leptodactylus marmoratus . Among these, the L. fuscus group is the one with most species, with 27 taxa. Characters unverified in most of the species are used to define the L. fuscus group. However, the monophyly of the group has never been tested rigorously in a quantitative phylogenetic context. Thus, the main goal of this study was to test such monophyly and to construct a phylogeny of the L. fuscus group. A matrix of 114 characters scored across 43 taxa was constructed, with 31 characters taken from external morphology, 58 from adult skeletons, 16 from larval chondrocranium, 5 from ethology and 4 from morphometric data were included. Out of all the species examined, 23 belonged to the ingroup and 20 to the outgroup. The data set was analysed with implied weights, by using TNT software. The monophyly of the group was strongly supported in the fittest cladogram obtained. The optimizations of some characters on this hypothesis support traditional evolutionary hypotheses. The optimizations also suggest the presence of paedomorphic character states in some species, which is also discussed.  相似文献   

4.
Abstract— A cladistic analysis of the South American grasshopper genera Scotussa and Leiotettix was performed in order to test the monophyly of these genera. Eurotettix, Chlorus and the Dichroplus bergi species group were included as terminal taxa. The genus Atrachelacris was used to root the tree. Twenty-nine characters from external morphology, male genitalia and female ovipositor were used in the analysis. In order to test for association between the structural change that occurred in the ovipositor valves of Scotussa and the functional change of the oviposition habits, the data matrix was partitioned and two analyses were performed. Characters from the female ovipositor were excluded from the data set used in the first analysis and another analysis was performed where all the characters were included in the analysis. Information on oviposition habits was then mapped on the cladogram, to determine the transformation for performance. Both analyses yielded only one most parsimonious tree and produced congruent results, confirming the monophyly of Leiotettix and Scotussa and corroborating their close relationship. Characters from the female ovipositor valves were informative not only at the species level but also at higher levels in the cladogram. The results also support the hypothesis of association between the structural change that occurred in the ovipositor valves of Scotussa with the functional change in the oviposition habits. However, this association did not seem to be correlated with the adaptive radiation in the genus.  相似文献   

5.
Based on recent molecular phylogenetic studies, the Old World bat family Miniopteridae, composed of species in the genus Miniopterus , has been shown to contain complex paraphyletic species, many of which are cryptic based on convergent morphological characters. Herein we resolve the phylogenetic relationships and taxonomy of the species complex M . manavi on Madagascar and in the Comoro Archipelago, where these animals occur in different bioclimatic zones. First using mitochondrial cytochrome- b sequence data to define clades and then morphology to corroborate the molecular data, including comparisons to type specimens, we demonstrate that animals identified as this taxon are a minimum of three species: M . manavi sensu stricto occurs in at least the central portion of the Central Highlands; M . griveaudi has a broad distribution in lowland northern and central western Madagascar and the Comoros (Anjouan and Grande Comore), and M . aelleni sp. n. has been found in northern and western Madagascar and the Comoros (Anjouan). In each case, these three clades were genetically divergent and monophyletic and the taxa are diagnosable based on different external and craniodental characters. One aspect that helped to define the systematics of this group was isolation of DNA from one of the paratypes of M. manavi collected in 1896 and new topotypic material. Miniopterus manavi is most closely allied to a recently described species, M. petersoni . At several localities, M . griveaudi and M . aelleni have been found in strict sympatry, and together with M. manavi sensu stricto show considerable convergence in morphological characters, but are not immediate sister taxa. In defining and resolving the systematics of cryptic species, such as miniopterid bats, the process of defining clades with molecular tools, segregating the specimens accordingly, and identifying corroborative morphological characters has been notably efficient.  相似文献   

6.
Li B  Liu Z  Zheng ZM 《ZooKeys》2011,(148):209-255
The grasshopper family Catantopidae is a well-known group, whose members include some of the most notorious agricultural pests. The existing classifications of the family are mostly utilitarian rather than being based on phylogenetic analysis and therefore unable to provide the stability desired for such an economically important group. In the present study, we present the first comprehensive phylogenetic analysis of the family based on morphology. By extensively sampling from the Chinese fauna, we included in the present analysis multiple representatives of each of the previously recognized tribes in the family. In total, we examined 94 genera represented by 240 species and evaluated 116 characters, including 84 for external morphology and 32 for male genitalia. The final matrix consists of 86 ingroup taxa and 88 characters. Our phylogenetic analyses resulted in a high resolution of the basal relationships of the family while showed considerable uncertainty about the relationships among some crown taxa. We further evaluated the usefulness of morphological characters in phylogeny reconstruction of the catantopids by examining character fit to the shortest trees found, and contrary to previous suggestions, our results suggest that genitalia characters are not as informative as external morphology in inferring higher-level relationship. We further suggest that earlier classification systems of grasshoppers in general and Catantopidae in particular most probably consist of many groups that are not natural due the heavy reliance on genitalia features and need to be revised in the light of future phylogenetic studies. Finally, we outlined a tentative classification scheme based on the results of our phylogenetic analysis.  相似文献   

7.
A manual cladistic analysis of the unnamed monophyletic taxon Alpheoidea plus Crangonoidea produced a cladogram containing 36 terminal taxa and 185 characters. The genealogical relationships of most of the 35 genera presently classified under the Hippolytidae have been resolved. Ten of these genera have been transferred, with the Processidae, from the Alpheoidea to the Crangonoidea. The concept of the Hippolytidae Bate, 1888 has been considerably restricted, the available names Lysmatidae Dana, 1852, Thoridae Kingsley, 1878, Hippolytinae Bate, 1888, and Latreutinae Ortmann, 1896 have been invalidated, and the new, family group names Barbouridae, Nauticarididae, Alopidae, and Bythocarididae are proposed. The traditional practice of naming monotypic taxa of suprageneric level has been avoided, yet all genealogical information indicated in the cladogram can be retrieved from the final classification proposed here for the Crangonoidea and Alpheoidea.  相似文献   

8.
选取生长习性、植物形态、木材解剖、花的形态结构、花粉特征以及胚胎学和染色体数目等共72个性状,采用最大简约法(Maximum Parsimony,MP)对旌节花科及其相关类群五桠果科、猕猴桃科、山茶科、金莲木科和省沽油科等进行分支分析。并用靴带检验法(Bootstrap)计算内部分支的支持率。分支图表明,旌节花科与省沽油科组成姊妹群,靴带支持率为79%,表明旌节花科与省沽油科具有最为密切的关系。旌节花科与猕猴桃科的关系次之,旌节花科和省沽油科与猕猴桃科关系的靴带支持率为58%。然后是山茶科。而旌节花科与金莲木科和五桠果科的关系则依次疏远。这与我们在孢粉学和胚胎学研究中所得的结论在某些方面是基本一致的。与Nandi等人用形态学数据和分子数据分析得到的结论也比较吻合,他们的结论也认为旌节花科与省沽油科具有比较密切的关系。只是他们把五桠果科和金莲木科摆在更近的位置,而山茶科和猕猴桃科则放在较疏远的位置上。  相似文献   

9.
Abstract — Morphological characters from sabethine mosquitoes were coded from larvae, pupae and adults, and life-stage partitions were evaluated to determine the contribution of each to the topology of a combined cladogram. Initial tests failed to find congruence between characters partitioned by life stage. However, when components from the combined analysis were tested using reduced taxon sets, a high degree of concordance between partitions was observed. A procedure for assessing individual life-stage contribution is employed, in which exhaustive searches are used to explore all possible arrangements for each of the selected components. Seven of the 10 components examined were able to recover the combined topology with a reduced taxon set. Congruent arrangements of taxa were typically observed for two or more life stages, although partitioned data were less resolved and frequently included aberrant topologies (those not supported by other partitioned or combined reduced taxon tree sets). In addition, none of the partitioned data sets gave robust results for all tests, suggesting that studies which emphasize character data from single life stages may support misleading arrangements of taxa. One component on the combined cladogram was not supported by any of the life-stage partitions when analysed separately. These results are complementary to “total evidence” approach, and demonstrate that partitions of data are useful for examining suits of characters which may cause some components of the “total  相似文献   

10.
Cladistic analyses of the animal kingdom   总被引:11,自引:0,他引:11  
A recently published book on the phylogeny of the animal kingdom, written by the first author, provided a classification based on a 'manual' cladistic analysis at the phylum level. We have extracted a data matrix consisting of 61 characters for 32 phyla from this book and treated it in more formal analyses using three different parsimony programs. Following a posteriori weighting, one cladogram emerged as the most parsimonious explanation of the data. This cladogram is compared to those in recent publications. Congruence is greatest with the phylogeny published by the first author, as the monophyly of 18 of the 21 supraphyletic categories proposed therein are supported in our cladogram. The exceptions are Aschelminthes, Frotornaeozoa and Neorenalia, but the latter group does emerge as a monophyletic taxon in a number of equally parsimonious, equally weighted trees. Comparisons with other recent phytogenies show varying degrees of divergence, especially concerning the monophyly of Spiralia and Aiticulata, both of which are advocated in the present paper. Significant characters of most of the supraphyletic taxa proposed by the first author are discussed. C1996 The Linnean Society of London  相似文献   

11.
POLYMORPHIC TAXA, MISSING VALUES AND CLADISTIC ANALYSIS   总被引:2,自引:0,他引:2  
Abstract Missing values have been used in cladistic analyses when data are unavailable, inapplicable or sometimes when character states are variable within terminal taxa. The practice of scoring taxa as having "missing values" for polymorphic characters introduces errors into the calculation of cladogram lengths and consistency indices because some character change is hidden within terminals. Because these hidden character steps are not counted, the set of most parsimonious cladograms may differ from those that would be found if polymorphic taxa had been broken into monomorphic subunits. In some cases, the trees found when polymorphisms are scored as missing values may not include any of the most parsimonious trees found when the data are scored properly. Additionally, in some cases, polymorphic taxa may be found to be polyphyletic when broken into monomorphic subunits; this is undetected when polymorphisms are treated as missing. Because of these problems, terminal units in cladistic analysis should be based on unique, fixed combinations of characters. Polymorphic taxa should be subdivided into subunits that are monomorphic for each character used in the analysis. Disregarding errors in topology, the additional hidden steps in a cladogram in which polymorphisms are scored as missing can be calculated by a simple formula, based on the observation that if it is assumed that polymorphic terminals include all combinations of character states, 2 p − 1 additional steps are required for each taxon in which p polymorphic binary characters are scored as missing values. Thus, when several polymorphisms are scored as missing in the same taxon, very large errors can be introduced into the calculation of tree length.  相似文献   

12.
Comparative larval morphology was used to elucidate phylogenetic relationships within the Pinnotheridae and the Dissodactylus species complex. Within the family, seven zoeal and six megalopal characters suggested two equally parsimonious phylogenetic hypotheses for pinnotherid larvae, both with Ostracotheres tridacnae representing the sister group for the Dissodactylus complex. Results indicated that the genus Pinnotheres is a polyphyletic taxon, and that the traditional subfamilial arrangement comprises paraphyletic taxa within the subfamilies Pinnotherinae and Pinnothereliinae. Certain evidence has suggested that Fabia and Juxtafubia should be excluded from the Pinnotherinae and placed into the Pinnothereliinae. Larval and adult morphology suggested that Pinnotheres politus should be included within Tumidotheres. The phylogenetic analysis within the Dissodactylus complex involved one zoeal and 16 megalopal characters. Results suggested a single phylogenetic hypothesis based on larval morphology. Combining adult morphology with larval evidence resulted in two equally parsimonious phylogenetic hypotheses, one of which agreed with a previously suggested hypothesis based only on adult characters.  相似文献   

13.
Abstract. Larval gut characters of 45 species of black flies, representing 17 subgenera and 15 genera, were studied for their utility in taxon diagnosis and phylogenetic inference. Phase-contrast and scanning electron microscopy revealed a wealth of new characters in the esophageal armature of the foregut. Larval gut morphology, particularly characters of the esophageal armature, varied significantly among taxa, permitting generic diagnoses. A cladogram inferred from 13 gut characters supported a sister-group relationship between Parasimulium and the remaining simuliids, but did not show a strong phylogenetic signal for the current, well-supported concept of tribal level monophyly.  相似文献   

14.
A total evidence phylogenetic analysis was performed for 14 extant and 18 fossil caniform genera using a data matrix of 5.6 kbp of concatenated sequence data from six independent loci and 80 morphological characters from the cranium and dentition. Maximum parsimony analysis recovered a single most parsimonious cladogram (MPC). The topology of the extant taxa in the MPC agreed with previous molecular phylogenies. Phylogenetic positions for fossil taxa indicate that several taxa previously described as early members of extant families (e.g., Bathygale and Plesictis) are likely stem taxa at the base of the Arctoidea. Taxa in the “Paleomustelidae” were found to be paraphyletic, but a monophyletic Oligobuninae was recovered within this set of taxa. This clade was closely related to the extant genera Gulo and Martes, therefore, nested within the extant radiation of the family Mustelidae. This analysis provides a resolution to several discrepancies between phylogenies considering either fossil taxa or extant taxa separately, and provides a framework for incorporating fossil and extant taxa into comprehensive combined evidence analyses.  相似文献   

15.
J R Stone 《Bio Systems》2001,61(1):33-39
The application of elementary equations from information theory to the elements involved in cladistic analysis is formalized mathematically. An equation is derived that quantifies the amount of information obtained by constructing a cladogram from a cladistic data matrix. Given particular conditions, the amount of information obtained increases monotonically with increases of the number of taxa involved and, so, may be used directly as a comparative measure of species richness for sister groups; in general, however, the amount of information obtained is related to the distribution of character states on the cladogram(s) deduced. An example is presented in which clades representing 11 phyla in the animal kingdom are compared in terms of information yielded. The amount of information obtained is consistent for different numbers of taxa and characters used in classifications. Speculative evolutionary explanations are presented for differences of information yielded among the phyla analyzed.  相似文献   

16.
Phylogenetic analyses of the leech family Macrobdellidae were accomplished with all nominal species in the family save one. A total of 17 specimens in nine ingroup species were analysed, along with four outgroup taxa. Twenty-two morphological characters based on jaw dentition, sexual anatomy, and external morphology failed to provide a resolution for many of the relationships in the family. DNA sequence data from nuclear 18S rDNA, nuclear 28S rDNA, mitochondrial 12S rDNA, and mitochondrial cytochrome c oxidase subunit I were examined separately and in combination with morphological characters. The resulting combined analysis strongly corroborated the placement of the genus Philobdella within the family Macrobdellidae and as sister to a monophyletic genus Macrobdella , the typical North American medicinal leeches. Furthermore, sequence divergences among these taxa confirmed the existence of two species, Philobdella gracilis and P. floridana , readily distinguishable on the basis of jaw dentition .  相似文献   

17.
Abstract. The phylogenetic relationships of tribes of the geometrid subfamily Sterrhinae (Lepidoptera) were studied, with special emphasis on finding delimiting characters for the tribe Scopulini. Two cladistic analyses were conducted for fifty‐nine species representing all previously recognized Sterrhinae tribes and covering the geographical range of the subfamily. In the first analysis, twelve putative synapomorphies of Scopulini, taken from the literature, were coded for actual specimens in order to test their ability to support the monophyly of the group. The resulting strict consensus cladogram was totally unresolved. In the second analysis, the twelve characters were combined with additional information from the morphology and ecology of adults and immature stages. Analysis of these ninety‐six characters resulted in a well‐resolved cladogram. The tribes were found to be monophyletic, except Cosymbiini and Rhodostrophiini. There are two main lineages within Sterrhinae: Cosymbiini + Rhodometrini + Timandrini and Rhodostrophiini + Cyllopodini + Sterrhini + Scopulini. Aletini and Problepsini lay within the concept of Scopulini. The association of the included Larentiinae taxa with the Cosymbiini + Rhodometrini + Timandrini lineage questions the monophyly of Sterrhinae. A majority of the recovered synapomorphic characters had been recognized previously, but several new phylogenetically informative characters were found, especially from the thorax. No unique characters diagnosing the tribe Scopulini were found, but many homoplastic synapomorphic features were found which diagnose parts of it. All recognized Sterrhinae genera are assigned tentatively to tribes and problematic cases are discussed.  相似文献   

18.
For Madagascan vicariance biogeography and phylogeny‐based conservation, four land snail groups have been predicted as most readily informative: Acavidae, Boucardicus (Cyclophoridae), Reticulapex (Charopidae), and Streptaxidae. Acavids have been evaluated in a previous paper; this paper uses recently described taxa from three mountains in southeastern Madagascar to evaluate the other three groups, based on shell and reproductive characters. Phylogenetic analyses, using appropriate outgroups, were performed on all 17 Boucardicus (31 characters, 120 states), all nine Reticulapex (21 characters, 53 states), and all 15 streptaxids (19 characters, 68 states) known from the three mountains. The Boucardicus cladogram was marginally robust; it supported monophyly of the genus, and it implied evolutionary trends toward larger, more colour‐patterned, more globose shells hatched from larger eggs; toward a dorsally and more weakly papillate penis with a large, external gland; and toward a broad‐based, tightly convoluted fertilization pouch‐seminal receptacle complex with an internal, muscular funnel. A convergence in high‐spired shells supported the recent synonymization of Madecataulus under Boucardicus. According to the cladogram, a three‐lobed apertural peristome was plesiomorphic, was lost, then reappeared convergently. Among the 12 dissected species of Boucardicus, morphology of the female reproductive system was extremely variable (11 of 14 character states autapomorphic). The Reticulapex cladogram supported monophyly of the genus but gave no robust resolution among species. Recent surveys also indicate that Reticulapex is rare to absent in northern Madagascar. The streptaxid cladogram suggested a sister‐group relationship between the endemic clades Par‐vedentulina and Streptostele (Makroconche), but provided no robust resolution among species within either clade or within Gulella. Anatomical material is relatively scarce for Madagascan streptaxids. Vicariance‐biogeographic analysis resulted in the area cladogram (northern Vohimena mountain chain (southern Vohimena chain (southern Anosy chain))). The Vohimena chain, already known for its significantly greater diversity and endemism than the Anosy chain, thus also séems to harbour the older, more plesiomorphic species; this heightens the urgency for conservation and further survey within the Vohimena chain. Acavids (115 species known) remain the most accessible of Madagascar's major, widespread land‐snail groups for island‐wide phylogenetics and biogeography, mainly because of existing frozen‐tissue collections, which have a limited shelf life. Boucardicus (177 species and 6 subspecies known) is clearly the second most accessible.  相似文献   

19.
Phylogenetic evidence for the herbaceous origin of angiosperms   总被引:7,自引:0,他引:7  
The ancestral angiosperm is commonly interpreted as an arborescent to shrubby magnolialean with large, multiparted, complex flowers. We examined this hypothesis using a phylogenetic analysis of new and reevaluated characters polarizabled with outgroup comparison. Our cladistic analysis of basal angiosperms placed the nonmagnolialeanChloranthaceae andPiperaceae at the bottom of the tree. We further inferred the probable ancestral states of characters not polarizable with outgroup comparison by examining their distribution among taxa at the base of our cladogram. The sum of ancestral character states suggests that the protoangiosperm was a diminutive, rhizomatous to scrambling perennial herb, with small, simple flowers.  相似文献   

20.
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