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1.
The nucleotide sequence of members of an alpha-repeat subfamily shared by human chromosomes 14 and 22 is presented. This subfamily is organized into a higher-order repeat unit composed of a tandem repetition of an ordered array of four related but distinct 340-bp repeat dimers. An analogous situation has been described for a related but distinct subfamily shared by chromosomes 13 and 21. These two subfamilies were further shown not to be present on the homologous chimpanzee chromosomes and therefore must have arisen by rearrangement of the human genome after separation of the two species. The sequence homology between the 13/21 and the 14/22 subfamilies is about 85%. The 14/22 subfamily represents the only major alphoid DNA species on these two chromosomes and is not present elsewhere in the human genome. Fluorescent in situ hybridizations show that sequences from the 13/21 and 14/22 subfamilies can be used as specific markers for their respective chromosomes.  相似文献   

2.
The 27 species of the aquatic frog family Pipidae are currently arranged in four genera: Xenopus (15 species), Hymenochirus (four species), and the poorly known genus Pseudhymenochirus (one species) occur in Africa; Pipa (seven species) is found in South America and lower Central America. Despite extensive work on the biology of Xenopus from various disciplines, the evolutionary relationships of Xenopus to other pipids have not been resolved. Phylogenetic analyis of morphological features of pipid frogs indicates that, contrary to earlier opinions, Hymenochirus and Pipa are closest relatives (sister-groups); these genera are placed in the subfamily Pipinae. Also, the currently recognized species of Xenopus do not form a natural group; the species tropicalis and epitropicalis are more closely related to Hymenochirus + Pipa than to the remaining species of Xenopus . The two discordant species are transferred to the genus Silurana , which is relegated to the new subfamily Siluraninae; it is the sister-group of the Pipinae. The remaining species of Xenopus constitute a monophyletic group that is placed in the subfamily Xenopodinae as the sister-group of the other genera of pipids.  相似文献   

3.
本文对广东滩涂经济鱼类寄生吸虫异肉科Allocreadiidae(Loose,1902)(Stossich,1903)和独睾科MonorchiidaeOdhner,(1911)进行研究,并建立拟履口吸虫属Paracrepidostomumgen.nov.是异肉科,履口亚科Crepidostominae(Dollfus,1951)的新属;长宫吸虫属Lenolopagen.nov是独睾科、孤睾亚科Lasiotocinae的新属。文中对二新属二新种:金钱鱼拟履口吸虫Paracrepidostomumscatophagusi和惠州长空吸虫Lenolopahuizhouensis分别进行了详细的描述,并对异肉科、履口亚科和属的分类特征进行修正、补充和讨论。  相似文献   

4.
The traditional avian subfamily Furnariinae, a group of terrestrial ovenbirds typical of the Andean and Patagonian arid zones, consists of the genera Furnarius, Cinclodes, Geositta, Upucerthia, Chilia, and Eremobius. We investigated phylogenetic relationships within the Furnariinae, with particular attention to the nine species of the genus Upucerthia, using nuclear and mitochondrial DNA sequences from all genera in the subfamily. Upucerthia was found to be highly polyphyletic, its constituent species forming four non-sister clades: (1) a basal lineage consisting of two Upucerthia species, U. ruficaudus and U. andaecola, as well as the monotypic genera Eremobius and Chilia; (2) a lineage consisting of U. harterti and U. certhioides, two species behaviorally divergent from other Upucerthia species; (3) a lineage consisting of U. serrana, which is not closely related to any other Upucerthia species; and (4) a lineage, sister to Cinclodes, consisting of the four Upucerthia species U. dumetaria, U. albigula, U. validirostris, and U. jelskii. The larger Furnariinae was also found to be highly polyphyletic; the terrestrial open country ecotype characteristic of this subfamily occurs in four unrelated clades in the family Furnariidae, including a basal lineage as well as derived lineages. Although the large degree of divergence among Upucerthia clades was not previously recognized, owing to ecological, behavioral, and morphological similarities, the groupings correspond closely to relationships suggested by plumage. This is in contrast to studies of other avian genera in which plumage patterns have been shown to be extensively convergent. The generic names Upucerthia and Ochetorhynchus are available for two of the former Upucerthia clades; new generic names may be warranted for the other two.  相似文献   

5.
Asteraceae is the largest plant family in México with about 417 genera and 3113 species, and with more than 60% of them being endemic. Phylogenetic relationships at subfamily and tribal levels have been previously resolved employing both nuclear and plastid molecular markers. However, Asteraceae species native to Mexico have been underrepresented in such phylogenies. To tackle this issue, the taxon sampling of this study included 90 Asteraceae species native to México, four species from the Caribbean, 119 previously sequenced species, and six outgroups. With this sampling, all the Asteraceae subfamilies and all of the tribes recognized to date are represented. The analyzed dataset consisted of eleven chloroplast markers (atpB, matK, ndhC, ndhD, ndhF, ndhI, ndhJ, ndhK, rbcL, trnL-trnF, and 23S-trnA). We present two phylogenetic reconstructions obtained by maximum likelihood and pseudocoalescent methods. Besides, we present a time-calibrated phylogeny, which is used to infer the best configuration of diversification rate shifts. Our results show that Mexican species are distributed mainly in the subfamily Asteroideae (80 species), followed by Cichorioideae (6 species), Carduoideae (2 species), and Mutisioideae (2 species). Four net diversification rate shifts were found: One near the base of the tree and four within Asteroideae subfamily. Our extended sampling of the family with the representation of native species to Mexico allowed us to identify important events in the evolutionary history of the family.  相似文献   

6.
A Comparison of the Sucrose Transporter Systems of Different Plant Species   总被引:5,自引:0,他引:5  
Abstract: The sucrose uptake behaviour of many different plant species is characterised by the presence of at least two components with distinct kinetic properties. These include at least one high-affinity and one low-affinity transport system. All known sucrose transporters from higher plants fall into one of three large subfamilies, according to phylogenetic analysis. Apparently, the largest subfamily, the SUT1 subfamily, exclusively consists of high-affinity sucrose transporters from dicotyledons, whereas none of the transporters from monocotyledonous plants groups within this subfamily. The other two subfamilies of sucrose transporter-like proteins are either low-affinity transporter or putative sucrose-sensing proteins. Most of the known sucrose transporters from monocotyledons are closely related to the SUT2 subfamily and include high-affinity transporters, suggesting a different evolutionary origin of dicotyledonous and monocotyledonous sucrose transporter gene families.  相似文献   

7.
The analysis of the morphological features of the genera of the family Linoproductidae in the Late Paleozoic substantiates its three subfamilies as three evolutionary trends beginning with the initial subfamily Coopericinae Lazarev, 2004, which is known from the beginning of the Early Carboniferous and two its derivatives: subfamily Linipalinae subfam. nov., which appeared in the Podolskian Time (Upper Moscovian Age), and subfamily Linoproductinae Stehli, 1954, which appeared in the Kasimovian Age. The problems and prospects of the further detailing of the system of these subfamilies are discussed. Three new species of the genus Sublinoproductus are described from the Lower Permian of Northern Timan.  相似文献   

8.
络新妇亚科曾归入园蛛科,后改为属于肖蛸科,目前又升格为科级阶元。为对络新妇亚科的分类地位作进一步研究,测定了9种蜘蛛线粒体12SrRNA基因的部分序列;另外还从GenBank检索到17种蜘蛛的12SrRNA基因的的相应序列。基于12SrRNA基因序列进行的分子系统发生分析结果表明络新妇亚科即不属于园蛛科、也不属于肖蛸科,而是与肖蛸科或园蛛科均无直接关联的独立支系,这个结果证实了将络新妇亚科升格为科级阶元的有效性。  相似文献   

9.
Species of the order Mysida (Crustacea, Peracarida) are shrimp-like animals that occur in vast numbers in coastal regions of the world. The order Mysida comprises 1,053 species and 165 genera. The present study covers 25 species of the well-defined Mysidae, the most speciose family within the order Mysida. 18S rRNA sequence analysis confirms that the subfamily Siriellinae is monophyletic. On the other hand the subfamily Gastrosaccinae is paraphyletic and the subfamily Mysinae, represented in this study by the tribes Mysini and Leptomysini, consistently resolves into three independent clades, and hence is clearly not monophyletic. The tribe Mysini is not monophyletic either, and forms two clades of which one appears to be closely related to the Leptomysini. Our results are concordant with a number of morphological differences urging a taxonomic revision of the Mysidae.  相似文献   

10.
A review and a list of eleven Iranian species of the subfamily Orgeriinae are given. Two new species are described, keys to the genera and species are provided. All the known localities are listed and mapped. Four species, including two new ones, are described in the Iranian fauna for the first time.  相似文献   

11.
本文对广东滩涂经济鱼类寄生复殖吸虫中的单孔科HaploporidaeNicoll,1914,单胜科HaplosplanchnidaePoche,1926和八睾科OctotestidaeYamaguti,1971吸虫进行研究,其中长尾亚科Elonainurinae和鲻长尾吸虫Elonginurusmuugilus分别作为单孔科的新亚科和新属新种;雄囊新单脏吸虫Neohaplosplanchnuscirrusaci作为单脏科的新属新种;天竺鲷八睾吸虫Octotestisapogoni作为八睾科、八睾吸虫属Octotestis(Wang,1963)Yamaguti,1951的新种。  相似文献   

12.
时敏  陈学新  马云  何俊华 《昆虫学报》2007,50(2):153-164
本研究选取矛茧蜂亚科Doryctinae(昆虫纲Insecta:膜翅目Hymenoptera:茧蜂科Braconidae)的6族15属18种做内群,茧蜂科其它7亚科11属11种做外群,首次结合同源核糖体28S rDNA D2基因序列片段和100个形态学和解剖学特征对该亚科进行了系统发育学研究。利用“非圆口类"的小腹茧蜂亚科Microgastrinae为根,以PAUP*4.0和MrBayes 3.0B4软件分别应用最大简约法(MP)和贝叶斯法对矛茧蜂亚科的分子数据和分子数据与非分子数据的结合体进行了运算分析;并以PAUP*4.0对矛茧蜂亚科的28S rDNA D2基因序列片段的碱基组成与碱基替代情况进行了分析。结果表明:矛茧蜂亚科的28S rDNA D2基因序列片段的GC含量在39.33%~48.28%之间变动,而对于碱基替代情况来讲,矛茧蜂亚科各成员间序列变异位点上颠换(transversion)大于转换(transition)。不同的分析算法所产生的系统发育树都表明矛茧蜂亚科是一个界限分明的单系群;在矛茧蜂亚科内,除了吉丁茧蜂族Siragrini为单系群外,其他族(矛茧蜂族Doryctini和方头茧蜂族Hecabolini)都是并系群。对于矛茧蜂亚科内各属之间的相互亲缘关系,不同算法所得的系统发育树的拓扑结构不完全一致,表明矛茧蜂亚科内(属及族)的系统发育关系还有待于进一步研究。  相似文献   

13.
14.
A morphological data set for the histerid beetle subfamily Saprininae comprising 95 adult morphological characters scored (multistate coding) from 72 terminal taxa and four outgroups was developed in order to analyse and determine the relationships amongst the genera and subgenera of the Saprininae subfamily. Cladograms were rooted with exemplars of Dendrophilinae (genus Dendrophilus), Bacaniini (genus Bacanius), Abraeinae (genus Chaetabraeus), and Anapleini (genus Anapleus). Parsimony‐based phylogenetic analyses were performed based on the type species of each genus and subgenus of the Saprininae occurring around the world, with the exception of three taxa: Paramyrmetes foveipennis (type species of the genus Paramyrmetes), Satrapister nitens (type species of the genus Satrapister) and Xerosaprinus (Auchmosaprinus) laciniatus (type species of the subgenus Auchmosaprinus) that were not available. In addition, in order to test the monophyly of several questionable genera, multiple exemplars were added in a few cases. The analysis also included an exemplar of an apparently undescribed genus. The results of the analysis confirm the monophyly of the subfamily supported by two unique synapomorphies: (1) presence of sensory structures of the antenna; and (2) presence of the antennal cavity, as well as several other weaker synapomorphies. However, the phylogeny inferred here shows mostly low support for the deeper branches and consequently no major changes in the Saprininae classification are proposed. The presented cladogram is discussed together with its implications for the evolution of the subfamily. The most informative characters and their respective states are outlined. Multiple shifts in lifestyles have evolved during the evolutionary history of the group. Taxa found near the root of the cladogram are mostly nidicolous or myrmecophilous, and inquiliny is presumed to be the plesiomorphic lifestyle of the subfamily. The nidicolous lifestyle has undergone several transformations to other lifestyles and myrmecophily has evolved three times independently during the evolution of the subfamily. Termitoxeny has evolved two times independently in the group whereas ecological adaptation for life in caves has likewise evolved two times independently. The analyses yielded a large clade of predominantly psammophilous taxa; psammophily is thought to have evolved once and has been subsequently lost several times. © 2014 The Linnean Society of London  相似文献   

15.
《FEBS letters》1986,201(1):74-80
Nucleotide sequence analysis of cDNA clones coding for field bean legumin precursor polypeptides revealed two different types, called A and B. Although homologous, both types differ in several sequence characteristics. Comparison with similar data from soybean and recent findings from pea leads to the following conclusions: (i) the two types of legumin genes described represent two subfamilies, A and B, which are probably of widespread occurrence; (ii) legumin genes or subunits can best be placed in either subfamily A or B by sequence homology, in addition B-type subunits contain generally fewer (or none at all in V. faba) Met residues as compared to A-type subunits; (iii) members of one subfamily from different species are more homologous than members of either subfamily within a species, therefore the two subfamilies must have arisen long before speciation of the genera Glycine, Pisum and Vicia; (iv) during speciation members of the B-subfamily diverged significantly more than members of the A-subfamily.  相似文献   

16.
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   

17.
本文对广东滩涂经济鱼类寄生复殖吸虫独睾科MonorchiidaeOdhner,1911中的两新种分别进行详细的描述,其中细长椭囊吸虫Elliptobursaattenuatussp.nov作为拟原穴亚科PseudoproctotrematinaeElliptobursa属的新种,巨穴孤睾吸虫Lasiotocusmarotremasp.nov作为孤睾亚科LasiotocinaeLasiotocus属  相似文献   

18.
The second communication of the survey deals with two subfamilies of the family Lyonetiidae: Lyonetiinae and Bedelliinae. The genus Phyllobrostis Stgr., not found in Russia hitherto, was earlier referred to the subfamily Cemiostominae (Seksyaeva, 1981, 1994), but now many authors include it in the subfamily Lyonetiinae (Karsholt and Razowski, 1996; Leraut, 1997). It is considered here within the latter subfamily, being mentioned here since findings of its representatives may be expected in Russia. The annotated list of Lyonetiinae and Bedelliinae of the fauna of Russia includes eight species from three genera.  相似文献   

19.
The DNA-DNA hybridization method was used to determine the divergence degree of unique sequences of five bivalvia species belonging to the Mytilinae subfamily. The matrix of delta Tm values for heteroduplexes of unique sequences was found which made it possible to define three phylogenetic branches within the subfamily. Under non-stringent hybridization conditions (55 degrees C, 0.5M PB) the divergence between species of any two branches was about 14% of nucleotide substitutions. The hybridization of [3H] unique sequences of Mytilinae with DNA fragments of Modiolus modiolus, a representative of the closest relative Modiolinae subfamily, showed that the divergence rate of unique sequences in two phylogenetic lines of the Mytilus genusis higher than in the line of the Crenomytilus genus I0.35-0.23% and 0.1% of nucleotide substitutions per one million years, respectively). According to the matrix of delta Tm values for five species of Mytilinae and Modiolus modiolus, a phylogenetic tree was built reflecting the differences between the divergence rates in different branches.  相似文献   

20.
1. Coat colour variation was studied in two viverrid species belonging to the subfamily Hemigalinae, on the basis of museum specimens and observations of live animals. 2. In both species, polymorphism and ontogenetic colour change occur, and in the Owston's civet, sexual dimorphism in coat colour was identified.  相似文献   

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