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Chen, J., Li, Q., Kong, L. & Zheng, X. (2011). Molecular phylogeny of venus clams (Mollusca, Bivalvia, Veneridae) with emphasis on the systematic position of taxa along the coast of mainland China. —Zoologica Scripta, 40, 260–271. Veneridae is the most richly speciose family of heterodont bivalves with high ecological and economic value. Attention to the Veneridae systematics has been raised since traditional conchology‐based ideas on relationships among the venerids were challenged by recent studies using molecular makers and other new approaches and methods. Herein, DNA sequence information from fragments of two mitochondrial genes (COI and 16S) and one nuclear protein‐coding gene (H3) for 135 taxa (128 venerids, five nonvenerid veneroids and two other outgroups) are used to reconstruct the phylogenetic relationships of venus clams under maximum parsimony, maximum likelihood and Bayesian inference approaches. According to our molecular results, the traditional Veneridae is not recovered as monophyletic and most of the nominal subfamilies and genera formed para‐polyphyletic clades. The findings indicate that the current venerid classification cannot validly reflect a natural subdivision. In the present study, the classification of taxa along the coast of mainland China within this family are also revised based on their phylogenetic position and morphological characters. The synonymization of chionine genus Placamen with Clausinella is rejected. Chionine subgenera Anomalodiscus and Cryptonema are given full generic rank again and incorporated into Venerinae and Tapetinae, respectively. Tapetine Marcia hiantina, M. japonica and M. marmorata were distantly related to Katelysia spp., so assigning those three species into the genus Katelysia by some malacologists is rejected herein. Our results also evidence that the synonymization of the genus Tigammona and Periglypta might be inappropriate.  相似文献   

3.
Abstract Partial mitochondrial gene sequences of 16 Culicoides species were determined to elucidate phylogenetic relations among species and to develop a molecular identification method for important virus vector species. In addition, the analysis found mitochondrial gene rearrangement in several species. Sequences of the mitochondrial genome region, cox1trnL2cox2 (1940–3785 bp) of 16 Culicoides and additional sequences were determined in some species, including whole mitochondrial genome sequences of Culicoides arakawae. Nine species showed common organization in this region, with three genes cox1trnL2cox2 and a small or no intergenic region (0–30 bp) between them. The other seven species showed translocation of tRNA and protein‐coding genes and/or insertion of AT‐rich non‐coding sequences (65–1846 bp) between the genes. The varied gene rearrangements among species within a genus is very rare for mitochondrial genome organization. Phylogenetic analyses based on the sequences of cox1+cox2 suggest a few clades among Japanese Culicoides species. No relationships between phylogenetic closeness and mitochondrial gene rearrangements were observed. Sequence data were used to establish a polymerase chain reaction tool to distinguish three important vector species from other Culicoides species, for which classification during larval stages is not advanced and identification is difficult.  相似文献   

4.
The Munnopsidae are a diverse group of asellote isopods that are an important component of deep‐sea fauna. Morphologically‐based phylogenetic inference attempts have proven to be of limited use due to the ecological and morphological diversity within the clade. Monophyly of the family is well‐established but relationships within the group remain unresolved. This project is the first molecularly‐based effort focused specifically on resolving phylogenetic relationships within the Munnopsidae. Partial 28S and COI and complete 18S genes were sequenced for 28 asellotes, 15 additional taxa were included from which only one or two of the three target sequences could be obtained, and 18S sequences for five additional taxa were available from GenBank. Sequences were analysed both as individual genes and in combination using Bayesian and maximum parsimony approaches. Each gene provided a phylogenetic signal that could be identified in the combined analyses, with 18S analyses providing the most resolution of phylogenetic relationships. The available representatives of subfamilies Munnopsinae and Ilyarachninae were monophyletic, as was the genus Munneurycope. Relationships within the subfamily Munnopsinae were well‐resolved by thorough taxon sampling, several new species were placed, and the need for taxonomic revision of Munnopsis/Munnopsoides was supported. These analyses supported putative Eurycope paraphyly and emphasized the need for careful revision of this highly variable genus. Tytthocope was sister to Munnopsurus. Syneurycope was suggested as the sister group to the ilyarachnines. Combined analyses provided increased support for clades suggested in at least two individual gene analyses and for clades not strongly contradicted by individual analyses. Further work is required to fully resolve the munnopsid phylogeny and should consist of increased taxon sampling for the complete 18S sequence and possibly identification of at least one slowly evolving, nuclear protein‐coding gene to resolve the basal polytomy and enable placement of the root.  相似文献   

5.
The largest Recent family of Bivalvia, the marine Veneridae with approximately 800 species, comprises one of the least understood and most poorly defined molluscan taxa, despite including some of the most economically important and abundant bivalves, for example quahog, Pismo clams, and Manila clams. A review of previous phylogenetic analyses including the superfamily Veneroidea (Veneridae, Petricolidae, Glauconomidae, Turtoniidae, Neoleptonidae) and within the Veneridae shows minimal taxon sampling leading to weak conclusions and few supported synapomorphies. New phylogenetic analyses on 114 taxa tested the monophyly of Veneroidea, Veneridae, and 17 nominal venerid subfamilies, using morphological (conchological, anatomical) data and molecular sequences from mitochondrial (16S, cytochrome oxidase I) and nuclear (28S, histone 3) genes. Morphological analyses using 45 exemplar taxa and 23 traditional characters were highly homoplastic and failed to reconstruct traditional veneroid classification. Full morphological analyses (31 characters) supported the monophyly of Veneroidea and Veneridae but only when certain taxa were excluded, revealing analytical difficulties caused by a suite of characters associated with neotenous or miniaturized morphology. Molecular analyses resulted in substantially higher clade consistency. The combined molecular data set resulted in significant support for a particular topology. The monophyly of Veneridae was supported only when Petricolidae and Turtoniidae were subsumed, and recognized as members with derived or neotenous morphologies, respectively. Morphological character mapping on molecular trees retained a high level of homoplasy, but revealed synapomorphies for major branch points and supported six subfamily groups (Dosiniinae, Gemminae, Samarangiinae, Sunettinae, Tapetinae, combined Chioninae + Venerinae). Glauconomidae and Neoleptonidae are provisionally maintained in Veneroidea pending further study; Petricolinae and Turtoniinae are placed in Veneridae. © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society, 2006, 148 , 439–521.  相似文献   

6.
Bayesian, maximum‐likelihood, and maximum‐parsimony phylogenies, constructed using nucleotide sequences from the plastid gene region trnK‐matK, are employed to investigate relationships within the Cactaceae. These phylogenies sample 666 plants representing 532 of the 1438 species recognized in the family. All four subfamilies, all nine tribes, and 69% of currently recognized genera of Cactaceae are sampled. We found strong support for three of the four currently recognized subfamilies, although relationships between subfamilies were not well defined. Major clades recovered within the largest subfamilies, Opuntioideae and Cactoideae, are reviewed; only three of the nine currently accepted tribes delimited within these subfamilies, the Cacteae, Rhipsalideae, and Opuntieae, are monophyletic, although the Opuntieae were recovered in only the Bayesian and maximum‐likelihood analyses, not in the maximum‐parsimony analysis, and more data are needed to reveal the status of the Cylindropuntieae, which may yet be monophyletic. Of the 42 genera with more than one exemplar in our study, only 17 were monophyletic; 14 of these genera were from subfamily Cactoideae and three from subfamily Opuntioideae. We present a synopsis of the status of the currently recognized genera.
© The Willi Hennig Society 2011.  相似文献   

7.
Members of the family Conopidae (Diptera) have been the focus of little targeted phylogenetic research. The most comprehensive test of phylogenetic support for the present subfamily classification of Conopidae is presented here using 66 specimens, including 59 species of Conopidae and seven outgroup taxa. Relationships among subfamily clades are also explored. A total of 6824 bp of DNA sequence data from five gene regions (12S ribosomal DNA, cytochrome c oxidase subunit I, cytochrome b, 28S ribosomal DNA and alanyl‐tRNA synthetase) are combined with 111 morphological characters in a combined analysis using both parsimony and Bayesian methods. Parsimony analysis recovers three shortest trees. Bayesian analysis recovers a nearly identical tree. Five monophyletic subfamilies of Conopidae are recovered. The rarely acknowledged Zodioninae is restored, including the genera Zodion and Parazodion. The genus Sicus is removed from Myopinae. Morphological synapomorphies are discussed for each subfamily and inter‐subfamily clade, including a comprehensive review of the character interpretaions of previous authors. Included are detailed comparative illustrations of male and female genitalia of representatives of all five subfamilies with new morphological interpretation.  相似文献   

8.
The phylogenetic relationships among the three subfamilies (Salmoninae, Coregoninae and Thymallinae) in the Salmonidae have not been addressed extensively at the molecular level. In this study, the whole mitochondrial genomes of two Thymallinae species, Thymallus arcticus and Thymallus thymallus were sequenced, and the published mitochondrial genome sequences of other salmonids were used for Bayesian and maximum‐likelihood phylogenetic analyses. These results support an ancestral Coregoninae, branching within the Salmonidae, with Thymallinae as the sister group to Salmoninae.  相似文献   

9.
We determined the complete mitochondrial genome sequence of Rhigonema thysanophora, the first representative of Rhigonematomorpha, and used this sequence along with 57 other nematode species for phylogenetic analyses. The R. thysanophora mtDNA is 15 015 bp and identical to all other chromadorean nematode mtDNAs published to date in that it contains 36 genes (lacking atp8) encoded in the same direction. Phylogenetic analyses of nucleotide and amino acid sequence data for the 12 protein‐coding genes recovered Rhigonematomorpha as the sister group to the heterakoid species, Ascaridia columbae (Ascaridomorpha). The organization of R. thysanophora mtDNA resembles the most common pattern for the Rhabditomorpha+Ascaridomorpha+Diplogasteromorpha clade in gene order, but with some substantial gene rearrangements. This similarity in gene order is in agreement with the sequence‐based analyses that indicate a close relationship between Rhigonematomorpha and Rhabditomorpha+Ascaridomorpha+Diplogasteromorpha. These results are consistent with certain analyses of nuclear SSU rDNA for R. thysanophora and some earlier classification systems that asserted phylogenetic affinity between Rhigonematomorpha and Ascaridomorpha, but inconsistent with morphology‐based phylogenetic hypotheses that suggested a close (taxonomic) relationship between rhigonematomorphs and oxyuridomorphs (pinworms). These observations must be tempered by noting that few rhigonematomorph species have been sequenced and included in phylogenetic analyses, and preliminary studies based on SSU rDNA suggest the group is not monophyletic. Additional mitochondrial genome sequences of rhigonematids are needed to characterize their phylogenetic relationships within Chromadorea, and to increase understanding of mitochondrial genome evolution.  相似文献   

10.
The planthopper family Cixiidae (Hemiptera: Fulgoromorpha) comprises approximately 160 genera and 2000 species divided in three subfamilies: Borystheninae, Bothriocerinae and Cixiinae, the later with 16 tribes. The current paper represents the first attempt to estimate phylogenetic relationships within Cixiidae based on molecular data. We use a total of 3652 bp sequence alignment of four genes: the mitochondrial coding genes Cytochrome c Oxidase subunit 1 (Cox1) and Cytochrome b (Cytb), a portion of the nuclear 18S rDNA and two non-contiguous portions of the nuclear 28S rDNA. The phylogenetic relationships of 72 terminal specimens were reconstructed using both maximum parsimony and Bayesian inference methods. Through the analysis of this empirical dataset, we also provide comparisons among different a priori partitioning strategies and the use of mixture models in a Bayesian framework. Our comparisons suggest that mixture models overcome the benefits obtained by partitioning the data according to codon position and gene identity, as they provide better accuracy in phylogenetic reconstructions. The recovered maximum parsimony and Bayesian inference phylogenies suggest that the family Cixiidae is paraphyletic in respect with Delphacidae. The paraphyly of the subfamily Cixiinae is also recovered by both approaches. In contrast to a morphological phylogeny recently proposed for cixiids, subfamilies Borystheninae and Bothriocerinae form a monophyletic group.  相似文献   

11.
The phylogenetic relationships of the tribe Rhingiini and the genus Cheilosia (Diptera, Syrphidae) were investigated using morphological and molecular characters. The genus Cheilosia is one of the most diverse lineages of hoverflies (Syrphidae). The mitochondrial protein coding gene cytochrome c oxidase subunit I (COI), and the D2‐3 region of the nuclear 28S rRNA gene were chosen for sequencing, and morphological characters were scored for both adults and immature stages. The combined dataset included 56 ingroup taxa. The datasets were analyzed separately and in conjunction, using both static and dynamic alignment under the parsimony criterion. The aim of the study was to assess the phylogenetic relationships of the tribe Rhingiini, and to explore if the subgenera of Cheilosia were supported as monophyletic clades. Results showed that the monophyly of subtribes of Rhingiini remained ambiguous, especially due to unstable phylogenetic placements of the genera Portevinia and Rhingia. We recovered most subgenera of Cheilosia as monophyletic clades. Dynamic alignment, using the optimization alignment program POY, always recovered more parsimonious topologies under all parameter weighting schemes, than did parsimony analyses using static alignment and analyzed with NONA.  相似文献   

12.
This study examined subfamilial relationships within Braconidae, using 4 kb of sequence data for 139 taxa. Genetic sampling included previously used markers for phylogenetic studies of Braconidae (28S and 18S rDNA) as well as new nuclear protein‐coding genes (CAD and ACC). Maximum likelihood and Bayesian inference of the concatenated dataset recovered a robust phylogeny, particularly for early divergences within the family. This study focused primarily on non‐cyclostome subfamilies, but the monophyly of the cyclostome complex was strongly supported. There was evidence supporting an independent clade, termed the aphidioid complex, as sister to the cyclostome complex of subfamilies. Maxfischeria was removed from Helconinae and placed within its own subfamily within the aphidioid complex. Most relationships within the cyclostome complex were poorly supported, probably because of lower taxonomic sampling within this group. Similar to other studies, there was strong support for the alysioid subcomplex containing Gnamptodontinae, Alysiinae, Opiinae and Exothecinae. Cenocoeliinae was recovered as sister to all other subfamilies within the euphoroid complex. Planitorus and Mannokeraia, previously placed in Betylobraconinae and Masoninae, respectively, were moved to the Euphorinae, and may share a close affiliation with Neoneurinae. Neoneurinae and Ecnomiinae were placed as tribes within Euphorinae. A sister relationship between the microgastroid and sigalphoid complexes was also recovered. The helconoid complex included a well‐supported lineage that is parasitic on lepidopteran larvae (macrocentroid subcomplex). Helconini was raised to subfamily status, and was recovered as sister to the macrocentroid subcomplex. Blacinae was demoted to tribal status and placed within the newly circumscribed subfamily Brachistinae, which also contains the tribes Diospilini, Brulleiini and Brachistini, all formerly in Helconinae.  相似文献   

13.
Phylogenetic relationships among the NBS-LRR (nucleotide binding site–leucine-rich repeat) resistance gene homologues (RGHs) from 30 genera and nine families were evaluated relative to phylogenies for these taxa. More than 800 NBS-LRR RGHs were analyzed, primarily from Fabaceae, Brassicaceae, Poaceae, and Solanaceae species, but also from representatives of other angiosperm and gymnosperm families. Parsimony, maximum likelihood, and distance methods were used to classify these RGHs relative to previously observed gene subfamilies as well as within more closely related sequence clades. Grouping sequences using a distance cutoff of 250 PAM units (point accepted mutations per 100 residues) identified at least five ancient sequence clades with representatives from several plant families: the previously observed TIR gene subfamily and a minimum of four deep splits within the non-TIR gene subfamily. The deep splits in the non-TIR subfamily are also reflected in comparisons of amino acid substitution rates in various species and in ratios of nonsynonymous-to-synonymous nucleotide substitution rates (K A/K S values) in Arabidopsis thaliana. Lower K A/K S values in the TIR than the non-TIR sequences suggest greater functional constraints in the TIR subfamily. At least three of the five identified ancient clades appear to predate the angiosperm–gymnosperm radiation. Monocot sequences are absent from the TIR subfamily, as observed in previous studies. In both subfamilies, clades with sequences separated by approximately 150 PAM units are family but not genus specific, providing a rough measure of minimum dates for the first diversification event within these clades. Within any one clade, particular taxa may be dramatically over- or underrepresented, suggesting preferential expansions or losses of certain RGH types within particular taxa and suggesting that no one species will provide models for all major sequence types in other taxa. Received: 13 June 2001 / Accepted: 22 October 2001  相似文献   

14.
We sequenced nearly the entire mitochondrial genome of Argyroneta aquatica, a wholly underwater‐living spider, thereby enhancing the available genomic information for Arachnida. The confirmed sequences contained the complete set of known genes present in other metazoan mitochondrial genomes. However, the mitochondrial gene order of A. aquatica was distinctly different from that of the most distant Chelicerata Limulus polyphemus (Xiphosura), probably because of a series of gene translocations and/or inversions. Comparison of arachnid mitochondrial gene orders for the purpose of phylogenetic inference is only minimally useful, but provides a strong signal in closely related lineages. To test the basal relationships and the evolutionary pattern of tRNA gene rearrangements among Arachnida, phylogenetic analyses using amino acid sequences of the 13 protein‐coding genes were performed. An interesting feature, the five 135‐bp tandem repeats and two 363‐bp tandem repeats, was identified in the putative control region. Although control region tandem repeats have been reported in many other arachnid and metazoan species, this is the first time it has been described in spiders.  相似文献   

15.
Sun M  Shen X  Liu H  Liu X  Wu Z  Liu B 《Marine Genomics》2011,4(3):159-165
Mitochondrial genomes play a significant role in the reconstruction of phylogenetic relationships within metazoans. There are still many controversies concerning the phylogenetic position of the phylum Bryozoa. In this research, we have finished the complete mitochondrial genome of one bryozoan (Tubulipora flabellaris), which is the first representative from the class Stenolaemata. The complete mitochondrial genome of T. flabellaris is 13,763 bp in length and contains 36 genes, which lacks the atp8 gene in contrast to the typical metazoan mitochondrial genomes. Gene arrangement comparisons indicate that the mitochondrial genome of T. flabellaris has unique gene order when compared with other metazoans. The four known bryozoans complete mitochondrial genomes also have very different gene arrangements, indicates that bryozoan mitochondrial genomes have experienced drastic rearrangements. To investigate the phylogenetic relationship of Bryozoa, phylogenetic analyses based on amino acid sequences of 11 protein coding genes (excluding atp6 and atp8) from 26 metazoan complete mitochondrial genomes were made utilizing Maximum Likelihood (ML) and Bayesian methods, respectively. The results indicate the monopoly of Lophotrochozoa and a close relationship between Chaetognatha and Bryozoa. However, more evidences are needed to clarify the relationship between two groups. Lophophorate appeared to be polyphyletic according to our analyses. Meanwhile, neither analysis supports close relationship between Branchiopod and Phoronida. Four bryozoans form a clade and the relationship among them is T. flabellaris + (F. hispida + (B. neritina + W. subtorquata)), which is in coincidence with traditional classification system.  相似文献   

16.
The utility of a nuclear protein-coding gene for reconstructing phylogenetic relationships within the family Culicidae was explored. Relationships among 13 species representing three subfamilies and nine genera of Culicidae were analyzed using a 762-bp fragment of coding sequence from the eye color gene, white. Outgroups for the study were two species from the sister group Chaoboridae. Sequences were determined from clone PCR products amplified from genomic DNA, and aligned following conceptual intron splicing and amino acid translation. Third codon positions were characterized by high levels of divergence and biased nucleotide composition, the intensity and direction of which varied among taxa. Equal weighting of all characters resulted in parsimony and neighboring-joining trees at odds with the generally accepted phylogenetic hypothesis based on morphology and rDNA sequences. The application of differential weighting schemes recovered the traditional hypothesis, in which the subfamily Anophelinae formed the basal clade. The subfamily Toxorhynchitinae occupied an intermediate position, and was a sister group to the subfamily Culicinae. Within Culicinae, the genera Sabethes and Tripteroides formed an ancestral clade, while the Culex-Deinocerites and Aedes- Haemagogus clades occupied increasingly derived positions in the molecular phylogeny. An intron present in the Culicinae- Toxorhynchitinae lineage and one outgroup taxon was absent in the basal Anophelinae lineage and the second outgroup taxon, suggesting that intron insertions or deletions may not always be reliable systematic characters.   相似文献   

17.
Recent advances in molecular phylogenetics are continuously changing our perception of decapod phylogeny. Although the two suborders Dendrobranchiata and Pleocyemata within the Decapoda are widely accepted, this taxonomic view is now challenged when using mitochondrial protein‐coding genes to investigate the decapod phylogeny, especially for the basal pleocyematan groups. Here, we enhanced taxonomic coverage by sequencing the genomes of two basal decapod taxa Alpheus distinguendus and Panulirus ornatus, representing two infraorders, Caridea and Achelata, respectively. Based on these two and other available mitochondrial genomes, we evaluated the usefulness of protein‐coding genes in resolving deep phylogenetic relationships of the Decapoda using maximum likelihood and Bayesian analyses. The mt genomic results revealed a novel gene order because of the reverse transposition of trnE (transfer, trn for Glutamate) and a pseudogene‐like trnS (AGN) [trn for Serine (S1, AGN)] in the mitochondrial genome of A. distinguendus, and a duplicate of 89 bp sequences in the putative noncoding region of P. ornatus. Our phylogenetic inferences suggest monophyly of the Decapoda and its two suborders, and that several lineages within the Reptantia are consistently recovered with high nodal supports. Our findings suggest that the best mitochondrial genome phylogeny can be found on the premise that systematic errors should be minimized as much as possible. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 471–481.  相似文献   

18.
A new parsimony analysis of 27 complete mitochondrial genomic sequences is conducted to investigate the phylogenetic relationships of plethodontid salamanders. This analysis focuses on the amount of character conflict between phylogenetic trees recovered from newly conducted parsimony searches and the Bayesian and maximum likelihood topology reported by Mueller et al. (2004 ; PNAS, 101, 13820–13825). Strong support for Hemidactylium as the sister taxon to all other plethodontids is recovered from parsimony analyses. Plotting area relationships on the most parsimonious phylogenetic tree suggests that eastern North America is the origin of the family Plethodontidae supporting the “Out of Appalachia” hypothesis. A new taxonomy that recognizes clades recovered from phylogenetic analyses is proposed. © The Willi Hennig Society 2005.  相似文献   

19.
The order Archaeognatha was an ancient group of Hexapoda and was considered as the most primitive of living insects. Two extant families (Meinertellidae and Machilidae) consisted of approximately 500 species. This study determined 3 complete mitochondrial genomes and 2 nearly complete mitochondrial genome sequences of the bristletail. The size of the 5 mitochondrial genome sequences of bristletail were relatively modest, containing 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and one control region. The gene orders were identical to that of Drosophila yakuba and most bristletail species suggesting a conserved genome evolution within the Archaeognatha. In order to estimate archaeognathan evolutionary relationships, phylogenetic analyses were conducted using concatenated nucleotide sequences of 13 protein-coding genes, with four different computational algorithms (NJ, MP, ML and BI). Based on the results, the monophyly of the family Machilidae was challenged by both datasets (W12 and G12 datasets). The relationships among archaeognathan subfamilies seemed to be tangled and the subfamily Machilinae was also believed to be a paraphyletic group in our study.  相似文献   

20.
The complete mitochondrial genome sequence is determined for Paracymoriza prodigalis (Leech, 1889). The 15,326 bp circular molecule possesses a gene organization and order identical to other sequenced Pyraloidea mitochondrial genomes. All tRNAs have the typical clover-leaf structure except for tRNASer(AGN), which lacks the dihydrouridine (DHU) arm. The A+T-rich region of 343 bp includes the features common to the Lepidoptera, including the ‘ATAGA’ followed by an 19-bp poly-T stretch, but the tandem repeat sequences often appearing in available insects are not found. Phylogenetic relationships of eight subfamilies of 14 Pyraloidea species were constructed based on 13 PCGs of mitochondrial genomes using Bayesian inference (BI) and maximum likelihood (ML) methods. These phylogenies of the subfamilies within Pyraloidea accord well with morphological phylogenetic analysis except for the position of Schoenobiinae.  相似文献   

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