scholarly journals A phylogenomic framework and timescale for comparative studies of tunicates

2017 ◽  
Author(s):  
Frédéric Delsuc ◽  
Hervé Philippe ◽  
Georgia Tsagkogeorga ◽  
Paul Simion ◽  
Marie-Ka Tilak ◽  
...  
Keyword(s):  
Developmental Biology ◽  
Phylogenetic Analyses ◽  
Nuclear Gene ◽  
Sister Group ◽  
Evolutionary Developmental Biology ◽  
Sequence Evolution ◽  
Precise Position ◽  
Representative Species ◽  
Vertebrate Model ◽  
Phylogenetic Framework

AbstractBackgroundTunicates are the closest relatives of vertebrates and are widely used as models to study the evolutionary developmental biology of chordates. Their phylogeny, however, remains poorly understood and to date, only the 18S rRNA nuclear gene and mitogenomes have been used to delineate the major groups of tunicates. To resolve their evolutionary relationships and provide a first estimate of their divergence times, we used a transcriptomic approach to build a phylogenomic dataset including all major tunicate lineages, consisting of 258 evolutionarily conserved orthologous genes from representative species.ResultsPhylogenetic analyses using site-heterogeneous CAT mixture models of amino acid sequence evolution resulted in a strongly supported tree topology resolving the relationships among four major tunicate clades: 1) Appendicularia, 2) Thaliacea + Phlebobranchia + Aplousobranchia, 3) Molgulidae, and 4) Styelidae + Pyuridae. Notably, the morphologically derived Thaliacea are confirmed as the sister-group of the clade uniting Phlebobranchia + Aplousobranchia within which the precise position of the model ascidian genus Ciona remains uncertain. Relaxed molecular clock analyses accommodating the accelerated evolutionary rate of tunicates reveal ancient diversification (~450-350 million years ago) among the major groups and allow comparing their evolutionary age with respect to the major vertebrate model lineages.ConclusionsOur study represents the most comprehensive phylogenomic dataset for the main tunicate lineages. It offers a reference phylogenetic framework and first tentative timescale for tunicates, allowing the direct comparison with vertebrate model species in comparative genomics and evolutionary developmental biology studies.

scholarly journals Tackling the phylogenetic conundrum of Hydroidolina (Cnidaria: Medusozoa: Hydrozoa) by assessing competing tree topologies with targeted high-throughput sequencing

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12104
Author(s):  
Bastian Bentlage ◽  
Allen G. Collins
Keyword(s):  
Maximum Likelihood ◽  
High Throughput ◽  
High Throughput Sequencing ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
Life Cycles ◽  
Tree Topologies ◽  
Phylogenetic Framework ◽  
Phylogenetic Hypotheses ◽  
Inference Methods

Higher-level relationships of the Hydrozoan subclass Hydroidolina, which encompasses the vast majority of medusozoan cnidarian species diversity, have been elusive to confidently infer. The most widely adopted phylogenetic framework for Hydroidolina based on ribosomal RNA data received low support for several higher level relationships. To address this issue, we developed a set of RNA baits to target more than a hundred loci from the genomes of a broad taxonomic sample of Hydroidolina for high-throughput sequencing. Using these data, we inferred the relationships of Hydroidolina using maximum likelihood and Bayesian approaches. Both inference methods yielded well-supported phylogenetic hypotheses that largely agree with each other. Using maximum likelihood and Baysian hypothesis testing frameworks, we found that several alternate topological hypotheses proposed previously may be rejected in light of the genomic data generated for this study. Both the maximum likelihood and Bayesian topologies inferred herein consistently score well across testing frameworks, suggesting that their consensus represents the most likely phylogenetic hypothesis of Hydroidolina. This phylogenetic framework places Aplanulata as sister lineage to the remainder of Hydroidolina. This is a strong deviation from previous phylogenetic analyses that placed Capitata or Siphonophorae as sister group to the remainder of Hydroidolina. Considering that Aplanulata represents a lineage comprised of species that for the most part possess a life cycle involving a solitary polyp and free-swimming medusa stage, the phylogenetic hypotheses presented herein have potentially large implications for clarifying the evolution of life cycles, coloniality, and the division of labor in Hydrozoa as taxon sampling for phylogenetic analyses becomes more complete.

A molecular phylogenetic approach to Longidoridae (Nematoda: Dorylaimida)

Nematology ◽  
2005 ◽  
Vol 7 (1) ◽  
pp. 111-124 ◽  
Author(s):  
Yu He ◽  
Sergei A. Subbotin ◽  
Tatiana V. Rubtsova ◽  
Franco Lamberti ◽  
Derek J.F. Brown ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Strong Support ◽  
Nuclear Gene ◽  
Sister Group ◽  
Bayesian Posterior Probability ◽  
Molecular Phylogenetic ◽  
Secondary Structure Models ◽  
Outgroup Taxon ◽  
Lsu Rrna

Abstract The Longidoridae are a group of ectoparasitic nematodes including two subfamilies and six genera with hundreds of species. Sequences of the D2 and D3 expansion region of the large subunit (LSU) rRNA nuclear gene were amplified and used to reconstruct the phylogeny of longidorids. Phylogenetic analyses with maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI) were performed with one outgroup taxon and 62 longidorid sequences. Confidence of inferred clades was assessed by non-parametric bootstrapping for MP and Bayesian posterior probability for ML. All analyses placed Paralongidorus species as an inner group within the otherwise monophyletic genus Longidorus. The genus Xiphinema, except for X. americanum-group species, was placed as the sister group of Longidorus with strong support from the ML and BI analyses. The X. americanum-group was strongly supported as an exclusive clade to other genus Xiphinema species. The position of the Xiphidorus clade was not well resolved and the phylogenetic analyses did not support it as a sister group to Longidorus as previously inferred from morphology. Secondary structure models were constructed for the D2/D3 region of LSU rRNA for all studied species. It was found that sequence-based and structural morphometric rRNA phylogenies were incongruent.

Phylogeny of the semiaquatic bugs (Hemiptera-Heteroptera, Gerromorpha)

2008 ◽  
Vol 39 (4) ◽  
pp. 431-460 ◽  
Author(s):  
Jakob Damgaard
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Nuclear Gene ◽  
Sister Group ◽  
Morphological Characters ◽  
Mitochondrial Genes ◽  
Simultaneous Analysis ◽  
Sister Group Relationship ◽  
Individual Character ◽  
Aquatic Bugs

AbstractThe phylogeny of semi-aquatic bugs (Hemiptera-Heteroptera: Gerromorpha) was tested in parsimony analyses of 64 morphological characters and approximately 2.5 kb of DNA sequence data from the mitochondrial genes encoding COI+II and 16SrRNA and the nuclear gene encoding 28SrRNA. The taxon sample included representatives of all families and most subfamilies of Gerromorpha and a selection of outgroup taxa representing the two basal infraorders of Heteroptera, Enicocephalomorpha and Dipsocoromorpha, and two families of Nepomorpha. A simultaneous analysis (SA) of all data, and with gaps scored as fifth state characters, gave a single most parsimonious tree with all families resolved as monophyletic, except the Veliidae, where Microveliinae + Haloveliinae, Veliinae, Rhagoveliinae, Perittopinae, and Ocelloveliinae were resolved as successive sister groups to the Gerridae, thus confirming earlier statements about paraphyly of this family. The Gerridae + Veliidae clade was strongly supported, but otherwise only the Gerridae + Veliidae less Ocelloveliinae and the Gerridae itself had support. These three clades could all be diagnosed on apomorphic morphological characters, although no characters diagnosing the Gerridae were without convergences or present in all included taxa. While the Ocelloveliinae, Veliinae and Haloveliinae could not be diagnosed on convincing apomorphies, the Microveliinae + Haloveliinae, and their sister group relationship with the Gerridae, could be diagnosed on rather strong morphological synapomorphies, suggesting that Gerridae could be expanded to include these two veliid subfamilies, while Ocelloveliinae, and perhaps the remaining veliid subfamilies, could be elevated to new families. In Gerridae, the Ptilomerinae + Halobatinae was sister group to all other subfamilies, while the Rhagadotarsinae + Trepobatinae was sister group to a clade comprising the Gerrinae, Eotrechinae, Cylindrostethinae and Charmatometrinae. Most relationships in this clade were poorly supported and diagnosed, and Cylindrostethinae was surprisingly found to be paraphyletic. The sister group to the Gerridae + Veliidae clade was a strongly supported clade comprising the Paraphrynoveliidae and Macroveliidae, and this, and the lack of convincing synapomorphies for Paraphrynoveliidae, suggest that these two small families could be synonymized. For the basal relationships of Gerromorpha, the Mesoveliidae was strongly supported sister group to all other families, while the Hebridae, Hermatobatidae and Hydrometridae formed a poorly supported and poorly diagnosed sister group to the Gerridae + Veliidae + Paraphrynoveliidae + Macroveliidae clade. The unexpected sister group relationship between Hermatobatidae and Hydrometridae was moderately supported, and could be diagnosed on two synapomorphies, thus giving a new hypothesis about the relationships of these very divergent families. Phylogenetic analyses of individual character partitions gave less resolved and less supported relationships, and the mitochondrial genes COI+II and 16SrRNA contributed negative hidden partitioned Bremer support (HPBS) to the simultaneous analysis tree, probably due to homoplasy caused by saturation effects.

Taxonomic status of Velinoides Matsumura (Hemiptera: Reduviidae: Harpactorinae) inferred from mitochondrial and nuclear genes

Zootaxa ◽  
2009 ◽  
Vol 2080 (1) ◽  
pp. 55-68 ◽  
Author(s):  
HUI LIU ◽  
PING ZHAO ◽  
SHUJUAN LI ◽  
WANZHI CAI
Keyword(s):  
Phylogenetic Trees ◽  
Phylogenetic Analyses ◽  
Gene Segment ◽  
Nuclear Gene ◽  
Taxonomic Status ◽  
Sister Group ◽  
Molecular Data ◽  
28S Rrna ◽  
Minimum Evolution ◽  
Morphological Studies

In this study, we used three mitochondrial genes (cyt b, COI, and 16S rRNA) and one nuclear gene (28S rRNA) to evaluate the current taxonomic status of the genus Velinoides erected by Matsumura. Phylogenetic analyses of genes using maximum parsimony, maximum likelihood, and minimum evolution resulted in different phylogenetic trees. However, the combined dataset analysis revealed better phylogenetic relationships. The constructed phylogenies appeared to be largely congruent with morphological studies. Results based on the molecular data strongly supported that the C. dilatatus, the type species of Velinoides, was the sister group to all other species of the genus Coranus Curtis. Incorporation with the morphological and cytogenetic characteristics, we proposed that Velinoides is of subgeneric status, the genus Coranus Curtis should be divided into two subgenera, Velinoides Matsumura and Coranus Curtis. Our phylogenetic results suggested that the 28S rDNA gene segment alone might not be an optimal molecular marker for the phylogeny of the genus Coranus Curtis.

Molecular relationships of the Australian Ennominae (Lepidoptera: Geometridae) and implications for the phylogeny of the Geometridae from molecular and morphological data

Zootaxa ◽  
2006 ◽  
Vol 1264 (1) ◽  
pp. 1 ◽  
Author(s):  
CATHERINE J. YOUNG
Keyword(s):  
A Priori ◽  
Nuclear Gene ◽  
Sister Group ◽  
Morphological Characters ◽  
Molecular Data ◽  
Morphological Data ◽  
Protein Coding ◽  
Outgroup Species ◽  
Phylogenetic Framework ◽  
Molecular Relationships

Molecular data from the 28S D2 ribosomal nuclear gene fragment were utilised to construct a phylogeny for the Australian Ennominae. Sequences were obtained from 68 geometrid and 5 outgroup species. Sequences from a smaller subset of 17 species also were analysed using the nuclear protein-coding gene EF-1a. Species were sampled from all major subfamilies of the Geometridae as no a priori assumptions could be made confidently about possible sister groups to the Australian Ennominae.The major findings from these analyses were as follows:(a) Drepanidae are a sister group to Geometridae;(b) Larentiinae are derived basally within the Geometridae; the Sterrhinae are the penultimate basally derived group;(c) Oenochrominae s. str. are closely related to the Geometrinae.(d) Ennominae are not monophyletic;(e) Tasmanian Archiearinae are misplaced in the Archiearinae and have close affinities to Australian Nacophorini (Ennominae);(f) Australian Nacophorini are not monophyletic.These results are at odds with traditionally held beliefs on the origins of Geometridae but are in broad agreement with and elaborate on the findings of Abraham et al. (2001). The implications of these findings in relation to key morphological characters are discussed using the proposed phylogenetic framework.

Fossils, homology, and “Phylogenetic Paleo-ontogeny”: a reassessment of primary posterior plate homologies among fossil and living crinoids with insights from developmental biology

Paleobiology ◽  
2015 ◽  
Vol 41 (4) ◽  
pp. 570-591 ◽  
Author(s):  
David F. Wright
Keyword(s):  
Developmental Biology ◽  
Phylogenetic Analysis ◽  
Phylogenetic Analyses ◽  
A Priori ◽  
Evolutionary Developmental Biology ◽  
Phylogeny Reconstruction ◽  
Phylogenetic Systematics ◽  
Developmental Patterns ◽  
Single Plate ◽  
Homology Recognition

AbstractPaleobiologists must propose a priori hypotheses of homology when conducting a phylogenetic analysis of extinct taxa. The distributions of such “primary” homologies among species are fundamental to phylogeny reconstruction because they reflect a prior belief in what constitutes comparable organismal elements and are the principal determinants of the outcome of phylogenetic analysis. Problems arise when fossil morphology presents seemingly equivocal hypotheses of homology, herein referred to as antinomies. In groups where homology recognition has been elusive, such as echinoderms, these problems are commonly accompanied by the presence (and persistence) of poor descriptive terminology in taxonomic literature that confounds an understanding of characters and stymy phylogenetic research. This paper combines fossil morphology, phylogenetic systematics, and insights from evolutionary developmental biology to outline a research program in Phylogenetic Paleo-ontogeny. A “paleo” ontogenetic approach to character analysis provides a logical basis for homology recognition and discerning patterns of character evolution in a phylogenetic context. To illustrate the utility of the paleo-ontogenetic approach, I present a reassessment of historically contentious plate homologies for “pan-cladid” crinoids (Cladida, Flexibilia, Articulata). Developmental patterns in living crinoids were combined with the fossil record of pan-cladid morphologies to investigate primary posterior plate homologies. Results suggest the sequence of morphologic transitions unfolding during the ontogeny of extant crinoids are developmental relics of their Paleozoic precursors. Developmental genetic modules controlling posterior plate development in pan-cladid crinoids have likely experienced considerable constraint for over 250 million years and limited morphologic diversity in the complexity of calyx characters. Future phylogenetic analyses of pan-cladids are recommended to consider the presence of a single plate in the posterior region homologous with the radianal, rather than the anal X, as is commonly assumed.

scholarly journals Mitochondrial Genomes of Two Thaparocleidus Species (Platyhelminthes: Monogenea) Reveal the First rRNA Gene Rearrangement among the Neodermata

2019 ◽  
Vol 20 (17) ◽  
pp. 4214 ◽  
Author(s):  
Dong Zhang ◽  
Hong Zou ◽  
Ivan Jakovlić ◽  
Shan G. Wu ◽  
Ming Li ◽  
...  
Keyword(s):  
Gene Order ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Order Analysis ◽  
Coding Regions ◽  
High Gene ◽  
Phylogenetic Framework ◽  
Gene Order Rearrangement

Phylogenetic framework for the closely related Ancylodiscoidinae and Ancyrocephalinae subfamilies remains contentious. As this issue was never studied using a large molecular marker, we sequenced the first two Ancylodiscoidinae mitogenomes: Thaparocleidus asoti and Thaparocleidus varicus. Both mitogenomes had two non-coding regions (NCRs) that contained a number of repetitive hairpin-forming elements (RHE). Due to these, the mitogenome of T. asoti (16,074 bp) is the longest among the Monogenea; especially large is its major NCR, with 3500 bp, approximately 1500 bp of which could not be sequenced (thus, the total mitogenome size is ≈ 17,600 bp). Although RHEs have been identified in other monopisthocotyleans, they appear to be independently derived in different taxa. The presence of RHEs may have contributed to the high gene order rearrangement rate observed in the two mitogenomes, including the first report of a transposition of rRNA genes within the Neodermata. Phylogenetic analyses using mitogenomic dataset produced Dactylogyrinae embedded within the Ancyrocephalinae (paraphyly), whereas Ancylodiscoidinae formed a sister-group with them. This was also supported by the gene order analysis. 28S rDNA dataset produced polyphyletic Dactylogyridae and Ancyrocephalinae. The phylogeny of the two subfamilies shall have to be further evaluated with more data.

scholarly journals Phylogenomics and the evolution of hemipteroid insects

2018 ◽  
Vol 115 (50) ◽  
pp. 12775-12780 ◽  
Author(s):  
Kevin P. Johnson ◽  
Christopher H. Dietrich ◽  
Frank Friedrich ◽  
Rolf G. Beutel ◽  
Benjamin Wipfler ◽  
...  
Keyword(s):  
Large Scale ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
Single Copy ◽  
Molecular Dating ◽  
Protein Coding ◽  
Fossil Calibration ◽  
Large Scale Analysis ◽  
Phylogenetic Framework ◽  
Phylogenomic Analyses

Hemipteroid insects (Paraneoptera), with over 10% of all known insect diversity, are a major component of terrestrial and aquatic ecosystems. Previous phylogenetic analyses have not consistently resolved the relationships among major hemipteroid lineages. We provide maximum likelihood-based phylogenomic analyses of a taxonomically comprehensive dataset comprising sequences of 2,395 single-copy, protein-coding genes for 193 samples of hemipteroid insects and outgroups. These analyses yield a well-supported phylogeny for hemipteroid insects. Monophyly of each of the three hemipteroid orders (Psocodea, Thysanoptera, and Hemiptera) is strongly supported, as are most relationships among suborders and families. Thysanoptera (thrips) is strongly supported as sister to Hemiptera. However, as in a recent large-scale analysis sampling all insect orders, trees from our data matrices support Psocodea (bark lice and parasitic lice) as the sister group to the holometabolous insects (those with complete metamorphosis). In contrast, four-cluster likelihood mapping of these data does not support this result. A molecular dating analysis using 23 fossil calibration points suggests hemipteroid insects began diversifying before the Carboniferous, over 365 million years ago. We also explore implications for understanding the timing of diversification, the evolution of morphological traits, and the evolution of mitochondrial genome organization. These results provide a phylogenetic framework for future studies of the group.

scholarly journals The mitochondrial genomes of palaeopteran insects and insights into the early insect relationships

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Nan Song ◽  
Xinxin Li ◽  
Xinming Yin ◽  
Xinghao Li ◽  
Jian Yin ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Sister Group ◽  
Data Matrix ◽  
Mitochondrial Genomes ◽  
Sister Group Relationship ◽  
Sequence Evolution ◽  
Bayesian Inferences ◽  
Data Coding ◽  
Coding Schemes ◽  
The Family

AbstractPhylogenetic relationships of basal insects remain a matter of discussion. In particular, the relationships among Ephemeroptera, Odonata and Neoptera are the focus of debate. In this study, we used a next-generation sequencing approach to reconstruct new mitochondrial genomes (mitogenomes) from 18 species of basal insects, including six representatives of Ephemeroptera and 11 of Odonata, plus one species belonging to Zygentoma. We then compared the structures of the newly sequenced mitogenomes. A tRNA gene cluster of IMQM was found in three ephemeropteran species, which may serve as a potential synapomorphy for the family Heptageniidae. Combined with published insect mitogenome sequences, we constructed a data matrix with all 37 mitochondrial genes of 85 taxa, which had a sampling concentrating on the palaeopteran lineages. Phylogenetic analyses were performed based on various data coding schemes, using maximum likelihood and Bayesian inferences under different models of sequence evolution. Our results generally recovered Zygentoma as a monophyletic group, which formed a sister group to Pterygota. This confirmed the relatively primitive position of Zygentoma to Ephemeroptera, Odonata and Neoptera. Analyses using site-heterogeneous CAT-GTR model strongly supported the Palaeoptera clade, with the monophyletic Ephemeroptera being sister to the monophyletic Odonata. In addition, a sister group relationship between Palaeoptera and Neoptera was supported by the current mitogenomic data.

Molecular phylogeny of the Annelida

2000 ◽  
Vol 78 (11) ◽  
pp. 1873-1884 ◽  
Author(s):  
Damhnait McHugh
Keyword(s):  
Molecular Analysis ◽  
Phylogenetic Analyses ◽  
Strong Support ◽  
Nuclear Gene ◽  
Sister Group ◽  
The Body ◽  
Sister Group Relationship ◽  
Molecular Evidence ◽  
Gene Sequences ◽  
Sister Relationship

Traditionally, the Annelida has been classified as a group comprising the Polychaeta and the Clitellata. Recent phylogenetic analyses have led to profound changes in the view that the Annelida, as traditionally formulated, is a natural, monophyletic group. Both molecular and morphological analyses support placement of the Siboglinidae (formerly the Pogonophora) as a derived group within the Annelida; there is also evidence, based on molecular analysis of the nuclear gene elongation factor-1α, that the unsegmented echiurids are derived annelids. While monophyly of the Clitellata is well-supported by both molecular and morphological analyses, there is no molecular evidence to support monophyly of the polychaete annelids; the Clitellata fall within a paraphyletic polychaete grade. Relationships among groups of polychaete annelids have not yet been resolved by molecular analysis. Within the Clitellata, paraphyly of the Oligochaeta was indicated in a phylogenetic analysis of cytochrome c oxidase I, which supported a sister relationship between the leeches, including an acanthobdellid and a branchiobdellid, and two of the four oligochaetes in the analysis. There is some evidence from analysis of 18S rRNA sequences for a sister-group relationship between the clitellates and the taxon Aeolosoma. There is no agreement regarding the body form of the basal annelid, and while molecular analyses provide strong support for the Eutrochozoa, the identity of sister-group to the Annelida among the Eutrochozoa remains enigmatic. It is recommended that future investigations include additional conserved gene sequences and expanded taxon sampling. It is likely that the most productive approach to resolving annelid phylogeny, and thus increasing our understanding of annelid evolution, will come from combined analyses of several gene sequences.

Sign in / Sign up

Export Citation Format

Share Document