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1.
中国灵猫科的支序系统学分析   总被引:3,自引:0,他引:3  
选取分布于中国境内的8属9种灵猫科动物的88个骨骼性状、31个外部形态性状和1个行为性状,运用替代外群法分别以赤狐(犬科狐属)和青鼬(鼬科貂属)共同或单独作为外群进行支序分析,得出10个支序图,其步长(TL)为:106~136,一致性指数(CI)为0.581—0.660,保留指数(RI)为0.610—0.714。经合意分析得到4个相似的支序图,其TL为41—136,CI为0.581—0.732,RI为0.610—0.818,结果支持:①斑灵狸、大灵猫、小灵猫构成一个单系群,与传统分类一致(均属灵猫亚科);②椰子狸、花面狸、熊狸构成一个单系群,与传统分类一致(均属长尾狸亚科);③红颊獴、食蟹獴与灵猫科其他种为姐妹群关系(Bootstrap检验支持率100%),建议獴类为一亚科;④长颌带狸拥有较多自近裔性状如三个门齿孔,是一个高度特化的种类,其系统地位有待进一步研究。  相似文献   

2.
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   

3.
Peterson KR  Pfister DH 《Mycologia》2010,102(6):1398-1416
Cyttaria species (Leotiomycetes, Cyttariales) are obligate, biotrophic associates of Nothofagus (Hamamelididae, Nothofagaceae), the southern beech. As such Cyttaria species are restricted to the southern hemisphere, inhabiting southern South America (Argentina and Chile) and southeastern Australasia (southeastern Australia including Tasmania, and New Zealand). The relationship of Cyttaria to other Leotiomycetes and the relationships among species of Cyttaria were investigated with newly generated sequences of partial nucSSU, nucLSU and mitSSU rRNA, as well as TEF1 sequence data and morphological data. Results found Cyttaria to be defined as a strongly supported clade. There is evidence for a close relationship between Cyttaria and these members of the Helotiales: Cordierites, certain Encoelia spp., Ionomidotis and to a lesser extent Chlorociboria. Order Cyttariales is supported by molecular data, as well as by the unique endostromatic apothecia, lack of chitin and highly specific habit of Cyttaria species. Twelve Cyttaria species are hypothesized, including all 11 currently accepted species plus an undescribed species that accommodates specimens known in New Zealand by the misapplied name C. gunnii, as revealed by molecular data. Thus the name C. gunnii sensu stricto is reserved for specimens occurring on N. cunninghamii in Australia, including Tasmania. Morphological data now support the continued recognition of C. septentrionalis as a species separate from C. gunnii. Three major clades are identified within Cyttaria: one in South America hosted by subgenus Nothofagus, another in South America hosted by subgenera Nothofagus and Lophozonia, and a third in South America and Australasia hosted by subgenus Lophozonia, thus producing a non-monophyletic grade of South American species and a monophyletic clade of Australasian species, including monophyletic Australian and New Zealand clades. Cyttaria species do not sort into clades according to their associations with subgenera Lophozonia and Nothofagus.  相似文献   

4.
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   

5.
Abstract— The weevil genus Listroderes Schoenherr is a monophyletic group defined by the body vestiture consisting of subcircular to suboval scales, and comprises 35 species endemic to southern South America. A cladistic analysis of the genus was carried out using 44 characters from external morphology, body vestiture, and male and female genitalia. The curvipes (three species), nodifer (five species) and robustus (four species) species groups and the 23 species of the costirostris species group were considered terminal taxa. Apomorphic states were identified using the genus Hyperoides Marshall as outgroup. The analysis yielded 122 equally parsimonious cladograms, each with 89 steps and a consistency index of 0.42; a successive weighting procedure resulted in nine cladograms (consistency index of 0.69 and retention index of 0.85). In the general consensus cladogram, nodifer-robustus and curvipes-costirostris are two pairs of sister species groups. The costirostris group comprises the subgroups foveatus, angusticeps, costirostris, delaiguei, bimaculatus and elegans , in phylogenetic order. A distributional analysis of the species of Listroderes led to identification of four areas of endemism, namely central Chile, sub-Antarctic, central Argentina and Chaco. A vicariance biogeographic analysis of these areas, based on area cladograms of Listroderes, Hyperoides, Naupactus taeniatulus species group (Coleoptera: Curculionidae), and Lucilia generic group (Asteraceae) was carried out applying the three-area statements technique. According to the general area cladogram the sequence of area-fragmentation is as follows: (central Chile (sub-Antarctic (central Argentina, Chaco))). This sequence is congruent with the history hypothesized for the region, where the uplift of the Andes (Oligocene-Pliocene) led to a progressive aridification, replacing the ancient subtropical forest by open-country environments.  相似文献   

6.
木兰科的分支分析   总被引:10,自引:1,他引:10  
主要以形态学、解剖学、细胞学为依据,以德坚木属为外类群,用分支分析的方法探讨了木兰科属间的系统发育关系。有23个分支单位,选取32个性状,根据外类群比较原则和化石地层学资料,确定了性状的祖征和衍征。对数据矩阵的分支分析使用PAUP3.1.1和Hennig 86 v.1.5分别在Macintosh和IBM机上运行,前者以启发法,后者以BB命令运算,经严格一致化处理,得到一致化分支图。结果表明:1)木  相似文献   

7.
Phylogeny and classification of Marantaceae   总被引:1,自引:0,他引:1  
Relationships of Marantaceae were estimated from nucleotide sequence variation in the rps16 intron (plastid DNA) and from morphological characters. Fifty-nine species (21 genera) formed the ingroup, and 12 species (12 genera) of other Zingiberales formed the outgroup. There is no support for the traditional subdivision of Marantaceae into a triovulate and a uniovulate tribe or the informal groups previously proposed. The so-called Donax group forms a paraphyletic grade that is basal within Marantaceae. Thalia appears as the distal branch of this grade, but its position is not supported in jackknife analysis. The so-called Calathea group is monophyletic in all shortest trees but not supported with greater than 50% jackknife. The genus Calathea appears to be paraphyletic. The Maranta and Phrynium groups are clearly polyphyletic. Maranta, Koernickanthe , and genera of the Mymsma group, all neotropical, form a strongly supported monophyletic group. The sister of this group is the palaeotropical genus Halopegia. Koernickanthe is nested within Maranta , as this genus is traditionally circumscribed. The African genera Ataenidia and Marantochloa form a strongly supported clade in which Ataenidia is the sister group to Marantochloa . Based on phylogeny it is concluded that Africa, in spite of being much poorer in species, is the most likely ancestral area of Marantaceae  相似文献   

8.
The genus Enkianthus (Ericaceae) has been subject to a cladistic analysis of morphological, anatomical, embryological, and cytological data, using two species of Clethra as outgroup. In order to evaluate the monophyly of Enkianthus , the genera Epigaea and Phyllodoce from the subfamily Rhododendroideae, and the genus Andromeda from the subfamily Vaccinioideae were also included in an initial analysis which yielded 20 equally parsimonious cladograms. The results indicated that Enkianthus is monophyletic, and a subsequent analysis with only the outgroup taxa and 14 species of Enkianthus yielded two equally parsimonious cladograms with a more resolved topology. In order to obtain strictly monophyletic taxa, the current subgeneric classification of Enkianthus is revised, recognizing four sections: Enkianthus (9 spp.), Andromedina (2 spp.), Meisteria (2 spp.), and Enkiantella (4 spp.). The paper provides a key, illustrations of representative taxa, a cladogram, and strict consensus trees.  相似文献   

9.
五味子科的系统发育:核糖体DNA ITS区序列证据   总被引:3,自引:0,他引:3  
The Schisandraceae is one of the most important taxa for understanding the origin and evolution of primitive angiosperms due to its basal position in the recent cladograms of the angiosperm based both on several gene sequences and on morphological characters, but phylogenetic relationships within the family are still unresolved. The sequences of nrDNA ITS region of 15 species representing four sections of Schisandra Michx., two sections of Kadsura Kaempf. ex Juss. and one outgroup, Illicium fargesii Finet et Gagnep., were used to reconstruct the phylogeny of Schisandraceae. Fourteen most parsimonious trees (Length=259, CI=0.934 and RI=0.889) were obtained from the analysis with I.fargesii as the outgroup. In the consensus tree, the genus Schisandra was found to be divided into three clades. Sect. Pleiostema formed a clade together with sect. Maximowiczia, sect. Sphaerostema was weakly supported to be the sister group of a clade comprising S. bicolor var. tuberculata and Kadsura species. In particular, S. bicolor var. tuberculata, a species of sect. Schisandra, was nested within Kadsura. It seems from this result and the morphological characters that Schisandra might not be a monophyletic group. According to the present molecular phylogeny, both elongated hypocarpium and deciduous habit originated independently at least twice in the Schisandraceae, and therefore, the value of the present morphological characters used in the classification of the family Schisandraceae should be reevaluated.  相似文献   

10.
PHYLOGENETIC RELATIONSHIPS IN SEED PLANTS   总被引:1,自引:0,他引:1  
Abstract— The phylogenetic relationships of nineteen extant and fossil seed plants are considered. Analysis of 31 characters produced ten topologically similar and equally parsimonious cladograms. A strict consensus tree derived from these cladograms places Lyginopteris as the sister taxon to the other seed plants included. Within this clade all the taxa considered, except medullosans and cycads, form a single monophyletic group defined by the presence of flattened seeds and saccate pollen ("platy-sperms"). Relationships between medullosans, cycads, and "platysperms" were not resolved, but within the "platysperm" clade conifers and cordaites ( Cordaixylon, Mesoxylon ) + Ginkgo form a monophyletic group ("coniferophytes"). The "higher platysperms" (glossopterids, Caytonia , corystosperms, Bennettitales, Pentoxylon , Gnetales, and angiosperms) are also monophyletic, but their relationship to "coniferophytes," peltasperms, and Callistophyton is unresolved. Pentoxylon is placed as sister taxon to the Bennettitales, and together they form the sister group to a clade in which Gnetales and angiosperm are sister taxa. The Bennettitales + Pentoxylon + Gnetales + angiosperms ("anthophytes") form a monophyletic sister group to the corystosperms. This analysis is compared with current classifications of seed plants. It does not support a close relationship between Bennettitales and cycads, it provides no evidence for seed plant polyphyly, and it strongly suggests that the current concept of seed ferns has little value in a phylogenetic context.  相似文献   

11.
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   

12.
The genus Crinum L. is the only pantropical genus of the Amaryllidaceae. Phylogenetic and biogeographical analyses of nrDNA ITS and plastid trnL-F sequences for all continental groups of the genus Crinum and related African genera are presented, with the genus Amaryllis used as outgroup. ITS indicates that C. baumii is more closely related to Ammocharis and Cybistetes than to Crinum sensu stricto . Three clades are resolved in Crinum s.s. One unites a monophyletic American group with tropical and North African species. The second includes all southern African species and the Australian endemic C. flaccidum . The third includes monophyletic Madagascar, Australasian and Sino-Himalayan clades, with southern African species. The trnL-F phylogeny resolves an American and an Asian/Madagscar clade, and confirms the relationship of C. flaccidum with species endemic to southern Africa. The salverform, actinomorphic perianths of subg. Crinum appear to have evolved several times in the genus from ancestors with zygomorphic perianths (subg. Codonocrinum ), thus neither subgenus is monophyletic. Biogeographical analyses place the origin of Crinum in southern Africa, as the region is optimized at all ancestral nodes in the tree topology, and in basal interior nodes of all but one of the major clades. The genus underwent three major waves of radiation corresponding to the three main clades resolved in our trees. Two entries into Australia for the genus are indicated, as are separate Sino-Himalayan and Australasian dispersal events.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 349–363.  相似文献   

13.
LU AN-MING, 1990. A preliminary cladistic study of the families of the superorder Lamiiflorae. A preliminary cladistic analysis was undertaken to evaluate the relationships between families of the superorder Lamiiflorae sensu Dahlgren. Several character complexes were surveyed, and ultimately 29 informative characters were used for the study. Three families, Clethraceae, Oleaceae and Solanaceae were selected for outgroup comparison and polarization of the characters. A data matrix was constructed for the 23 ingroup families. The data matrix was analysed with the cladistic parsimony program Hennig86. Three equally parsimonious cladograms were found. Many family interrelationships could not be resolved, although several groups were common to all three cladograms, as shown by a strict consensus tree. The Retziaceae emerged as the sister group to the remaining families. About half of those appeared in a large polytomy in the consensus tree. There was also one possibly monophyletic complex of families involving the Lamiales with the families Verbenaceae, Lamiaceae, Phrymaceae and Callitrichaceae as well as the three isolated families Trapellaceae, Hippuridaceae, and Hydrostachyaceae. Within this complex, Verbenaceae and Lamiaceae came out as sister groups, as did Callitrichaceae and Hydrostachyaceae, with Hippuridaceae as sister group to them. However, the results must be regarded as tentative.  相似文献   

14.
似鮈类鱼类的系统发育研究(鲤形目:鲤科)   总被引:1,自引:0,他引:1  
本文通过对似类8属13种和外类群7属10种鱼类的比较研究,选取37个骨骼及外部特征,运用外类群比较法进行特征分析,根据分支系统学原理重建了似类的系统发育。特征分析和系统发育分析表明似类是具有许多共同离征的单系群,朝着流水性底栖生活和刮食性的主干方向发展;其中以似属最原始,胡属最特化构成7对姐妹群。蛇属是较早分化出的相对特化的类群,棒花鱼属和小鳔属的关系相对较远。  相似文献   

15.
Abstract. Myrmecia Fabricius is revised at species-group level. Nine groups are recognized: those of M.aberrans, M.cephalotes, M.gulosa, M.mandibularis, M.nigrocincta, M.picta, M.pilosula, M.tepperi and M. urens. A key to the species groups is provided, and worker diagnoses, illustrations and species lists are given for each. Eight groups are constituted much as in the previous classification of John Clark, but defined using new characters. Phylogenetic relationships are investigated, with six cladograms derived from four sets of data, each with a different outgroup. The most plausible cladograms suggest that: (1) the aberrans group is the sister group to the others; (2) the pilosula, tepperi and mandibularis groups constitute a monophyletic assemblage, though monophyly of the first two is not confirmed; (3) the gulosa, nigrocincta, urens and picta groups constitute a monophyletic assemblage, though monophyly of the picta group is not confirmed; (4) the phylogenetic position of the cephalotes group is unclear.  相似文献   

16.
Species delimitation in the genus Geopora (Pyronemataceae) is complicated because of small number of differentiating characters, values of which tend to overlap among the species. Current classification relies mainly on size and shape of ascospores and fruit-bodies, position of the apothecia in the ground and length of excipular hairs. We measured ascospores in ca. 90 Geopora specimens. Sequences of internal transcribed spacer (ITS) rDNA gene were obtained to investigate phylogenetic relationships in the genus. Maximum parsimony (MP) and Bayesian analyses reveal that the well-supported clades detected often do not correspond to the species concepts based on morphological characters. Nine out of the ten lineages include specimens which were initially identified as belonging to different species. The dimensions of ascospores vary to great extent within the lineages. The size and shape of fruit-bodies, length of excipular hair and hymenium colour are mostly homogenous within each clade; however, these characters coincide to a great extent among the lineages and the latter can be assessed only from fresh fruit-bodies. Nuclear DNA content, and accordingly, ploidy level do not provide evidence for species distinction. Geopora arenicola, G. tenuis and G. sepulta were recognized as monophyletic species. Geopora foliacea and G. cervina could not be explicitly delimited and the G. cervina complex comprising three clades was introduced.  相似文献   

17.
Phylogeny of the subfamilies of Chironomidae (Diptera)   总被引:1,自引:0,他引:1  
Summary The phylogeny of the subfamilies of Chironomidae are cladistically analysed using parsimony. A data matrix is presented and some characters discussed. Different outgroup taxa, constraints and options are used, characters unordered or ordered, weighted or unweighted, the results reweighted or not and the results discussed. Telmatogetoninae in all cladograms forms the sister group of the remaining subfamilies. Aphroteniinae in some cladograms forms the sister group of all subfamilies except Telmatogetoninae, whereas in other cladograms, including the preferred cladogram, it is part of Tanypodoinae, which otherwise includes Podonominae, Usumbaromyiinae and Tanypodinae. Chilenomyiinae is basal in Tanypodoinae in some cladograms. In most cladograms, including the preferred cladogram, it is basal in Chironomoinae, which also includes Buchonomyiinae, Diamesinae, Prodiamesinae, Orthocladiinae and Chironominae. The preferred cladogram is compared with the relationships between different subfamilies suggested by previous authors.  相似文献   

18.
This paper proposes a refined hypothesis of evolution for the tropical Indo-Pacific nudibranch genus Halgerda . Numerous specimens from 31 species were examined anatomically and literature from four additional species was reviewed, bringing to 33 the ingroup taxa. Fifty-three characters were considered from these examinations. The outgroup Asteronotus was used to polarize the characters. The phylogeny obtained from the analysis of the characters supports the hypothesis that Halgerda is a monophyletic group. A species previously placed with the genus Sclerodoris is examined and determined to be a member of the genus Halgerda . Phylogenetic analysis places this species, H. paliensis , as a basal member of the genus . Halgerda paliensis appears to be restricted to the Hawaiian Islands. Specimens previously identified as Sclerodoris paliensis from the Marshall Islands actually represent H. dalanghita Fahey & Gosliner, 1999. A new species, Halgerda onna , is described and presented as the sister taxon to a basal member of the genus. A range and depth extension of a previously described species, H. malesso , is presented. The present phylogeny is then compared to previous studies, in particular those of Fahey & Gosliner (1999a,b) .  相似文献   

19.
This paper studies the phylogenetic relationships of the nudibranch dorids that lack a radula. Numerous specimens belonging to 29 different species, representing all genera of this group and other related taxa, were examined anatomically. Details of the foregut were examined with SEM. From this anatomical study a total of 62 characters were considered. These characters have been polarized using the genus Berthella as the outgroup. Eight species of dorids with a radula and the genus Armina have been also included in the analysis for comparative purposes. The phylogeny obtained supports the hypothesis that the radula has been lost once in the Doridina and that the radula-less dorids are a monophyletic group. Cryptobranchia is monophyletic when the radula-less dorids are included. The new genus Mandelia , introduced on the basis of a new species from South Africa, is the sister group of the rest of the radula-less dorids, and is described as a new family, Mandeliidae. The radula-less dorids (currently placed in a separate superfamily) actually constitute an internal branch of other cryptobranch dorids. Phyllidia has no synapomorphies that distinguish if from Fryeria , which has one autoapomorphy, the ventral position of the anus. Therefore, both genera are regarded as synonyms. The evolution of several characters among the radula-less dorids is discussed, and the present phylogeny is compared with prior studies.  相似文献   

20.
论山毛榉科植物的系统发育   总被引:10,自引:2,他引:8  
本文运用分支分类学方法,对山毛榉科植物进行了系统发育的分析。山毛榉科作为单元发生群包括柯属、锥属、粟属、三棱栎属、水青冈属和栎属。桦木科和南山毛榉属被选择作为外类群。对大量的性状进行评估之后,选择了25对性状作为建立数据矩阵的基本资料。性状极化以外类群比较为主,同时也采用了化石证据和通行的形态演化的基本原则。数据矩阵由7个分类群、2个外类群和25个性状组成。采用最大同步法、演化极端结合法和综合分析法对该数据矩阵进行了分析。在得到的3个树状分支图中按照最简约的原则,选出演化长度最短的谱系分支图作为本文讨论山毛榉科属间的系统演化关系的基础。关于山毛榉科植物的系统发育,作者的观点如下:(A)现存的山毛榉科的6个属形成了4条平行进化的分支路线,它们分别被处理作4个亚科,即:栗亚科,三棱栎亚科,水青冈亚科和栎亚科;(B)平行进化是山毛榉科植物系统发育过程中的主要形式。生殖过程中的一些特征,如:果实第二年成熟,胚珠通常败育等,是影响山毛榉科植物属间基因交流的主要原因。在现存的山毛榉科植物中,柯属是最原始的类群。三棱栎属和锥属的起源也较早,而栗属、水青冈属和栎属是特化的类群。  相似文献   

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