scholarly journals New insights into the phylogeny, systematics and DNA barcoding of Nemertea

2014 ◽  
Vol 28 (3) ◽  
pp. 287 ◽  
Author(s):  
Sebastian Kvist ◽  
Christopher E. Laumer ◽  
Juan Junoy ◽  
Gonzalo Giribet
Keyword(s):  
Dna Barcoding ◽  
18S Rrna ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
28S Rrna ◽  
Variable Regions ◽  
Molecular Phylogenetic ◽  
Coi Sequences ◽  
Length Variable ◽  
High Support

Although some clades of ribbon worms (phylum Nemertea) are consistently recovered with high support in molecular phylogenies, the placement and inter-relationships of some taxa have proven problematic. Herein, we performed molecular phylogenetic analyses aimed at resolving these recalcitrant splits, using six loci (nuclear 18S rRNA, 28S rRNA, histones H3 and H4, and mitochondrial 16S rRNA and COI) for 133 terminals, with particular emphasis on the problematic families Hubrechtidae and Plectonemertidae. Three different datasets were used for phylogenetic analyses and both maximum likelihood and maximum parsimony methodologies were applied. All but one of the resulting tree topologies agree on the paraphyly of the class Palaeonemertea, whereas Heteronemertea, Hoplonemertea, Polystilifera, Monostilifera and Hubrechtidae are always recovered as reciprocally monophyletic. Hubrechtidae is sister group to Heteronemertea (the Pilidiophora hypothesis) only when length variable regions of 18S rRNA and 28S rRNA are excluded. Moreover, the terrestrial and freshwater family Plectonemertidae is recovered with high support and the implications of this finding are further discussed. Finally, we evaluate the utility of DNA barcoding for specimen identification within Nemertea using an extended dataset containing 394 COI sequences. Results suggest that DNA barcoding may work for Nemertea, insofar as a distinct barcoding gap (the gap between the maximum intraspecific variation and the minimum interspecific divergence) may exist, but its recognition is regularly hampered by low accuracy in species level identifications.

scholarly journals Robust phylogenetic position of the enigmatic hydrozoan, Margelopsis haeckelii revealed within the family Corymorphidae

2021 ◽  
Author(s):  
Daria M. Kupaeva ◽  
Tatiana S. Lebedeva ◽  
Tatiana P. Ashurkova ◽  
Andrey A. Prudkovsky ◽  
Daniel Vanwalleghem ◽  
...  
Keyword(s):  
18S Rrna ◽  
Phylogenetic Signal ◽  
Sister Group ◽  
Molecular Study ◽  
Phylogenetic Position ◽  
28S Rrna ◽  
Recent Molecular Study ◽  
The Family ◽  
Molecular Phylogenetic ◽  
Multigene Analyses

The life-cycle and polyp morphology of Margelopsidae representatives are very different from all other Aplanulata cnidarians. Until recently, their evolutionary origin and phylogenetic position has been a subject of significant speculation. A recent molecular study based only on COI data unexpectedly placed Margelopsidae as a sister group to all Aplanulata, despite the Margelopsid morphology suggests affiliation with Tubulariidae or Corymorphidae. Here we used multigene analyses, including nuclear (18S rRNA and 28S rRNA) and mitochondrial (16S rRNA and COI) markers of the Margelopsidae hydroid Margelopsis haeckelii Hartlaub, 1897, to resolve its phylogenetic position with respect to other hydrozoans. Our data provides strong evidence that M. haeckelii is a member of the family Corymorphydae, making the family Margelopsidae invalid. Furthermore, we show that medusa previously known as M. harlaubii Browne, 1903 is sister to Plotocnide borealis, Wagner, 1885 and might be a member of Boreohydridae. The phylogenetic signal of polyp and medusа stages is discussed in light of concept of inconsistent evolution and molecular phylogenetic analysis.

Phylogeny of hymenolepidids (Cestoda: Cyclophyllidea) from mammals: sequences of 18S rRNA and COI genes confirm major clades revealed by the 28S rRNA analyses

2021 ◽  
Vol 95 ◽  
Author(s):  
B. Neov ◽  
G.P. Vasileva ◽  
G. Radoslavov ◽  
P. Hristov ◽  
D.T.J. Littlewood ◽  
...  
Keyword(s):  
Ribosomal Rna ◽  
18S Rrna ◽  
Phylogenetic Analyses ◽  
The Other ◽  
Rrna Genes ◽  
Host Switching ◽  
28S Rrna ◽  
Mitochondrial Cytochrome ◽  
Rapid Radiation ◽  
18S Rrna Genes

Abstract The aim of the study is to test a hypothesis for the phylogenetic relationships among mammalian hymenolepidid tapeworms, based on partial (D1–D3) nuclear 28S ribosomal RNA (rRNA) genes, by estimating new molecular phylogenies for the group based on partial mitochondrial cytochrome c oxidase I (COI) and nuclear 18S rRNA genes, as well as a combined analysis using all three genes. New sequences of COI and 18S rRNA genes were obtained for Coronacanthus integrus, C. magnihamatus, C. omissus, C. vassilevi, Ditestolepis diaphana, Lineolepis scutigera, Spasskylepis ovaluteri, Staphylocystis tiara, S. furcata, S. uncinata, Vaucherilepis trichophorus and Neoskrjabinolepis sp. The phylogenetic analyses confirmed the major clades identified by Haukisalmi et al. (Zoologica Scripta 39: 631–641, 2010): Ditestolepis clade, Hymenolepis clade, Rodentolepis clade and Arostrilepis clade. While the Ditestolepis clade is associated with soricids, the structure of the other three clades suggests multiple evolutionary events of host switching between shrews and rodents. Two of the present analyses (18S rRNA and COI genes) show that the basal relationships of the four mammalian clades are branching at the same polytomy with several hymenolepidids from birds (both terrestrial and aquatic). This may indicate a rapid radiation of the group, with multiple events of colonizations of mammalian hosts by avian parasites.

Asian Betylobraconinae (Hymenoptera, Braconidae), with description of a new genus and phylogenetic affinities of the tribe Facitorini

2008 ◽  
Vol 39 (2) ◽  
pp. 133-154 ◽  
Author(s):  
Alberto Sáez ◽  
Kaoru Maeto ◽  
Alejandro Zaldivar-Riverón ◽  
Sergey Belokobylskij
Keyword(s):  
New Species ◽  
Type Species ◽  
New Genus ◽  
Phylogenetic Analyses ◽  
28S Rrna ◽  
Asian Region ◽  
Molecular Phylogenetic ◽  
Phylogenetic Affinities ◽  
One New Species ◽  
Rrna Sequences

AbstractThe taxonomy of the Asian genera of the subfamily Betylobraconinae, a small and understudied group within the hymenopteran family Braconidae, is revised. A new genus exclusively from the Asian region, Asiabregma gen. nov., containing three species (A. ryukyuensis sp. nov. (type species, Japan and Malaya), A. makiharai sp. nov. (Japan) and A. sulaensis (van Achterberg), comb. nov. (Indonesia)) is described. One new species of Aulosaphobracon, A. striatus sp. nov. from Vietnam, and one of Facitorus, F. amamioshimus sp. nov. from Japan, are also described. Based on molecular phylogenetic analyses using COI mtDNA and 28S rRNA sequences, the three genera previously placed in the tribe Facitorini, Facitorus, Conobregma and Jannya, together with Asiabregma gen. nov., are transferred to the rogadine tribe Yeliconini.

scholarly journals Discovery of a new family of amphibians from northeast India with ancient links to Africa

2012 ◽  
Vol 279 (1737) ◽  
pp. 2396-2401 ◽  
Author(s):  
Rachunliu G. Kamei ◽  
Diego San Mauro ◽  
David J. Gower ◽  
Ines Van Bocxlaer ◽  
Emma Sherratt ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Nuclear Dna ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
Northeast India ◽  
Sister Group Relationship ◽  
New Family ◽  
Ancient Lineage ◽  
Molecular Phylogenetic ◽  
Threatened Habitats

The limbless, primarily soil-dwelling and tropical caecilian amphibians (Gymnophiona) comprise the least known order of tetrapods. On the basis of unprecedented extensive fieldwork, we report the discovery of a previously overlooked, ancient lineage and radiation of caecilians from threatened habitats in the underexplored states of northeast India. Molecular phylogenetic analyses of mitogenomic and nuclear DNA sequences, and comparative cranial anatomy indicate an unexpected sister-group relationship with the exclusively African family Herpelidae. Relaxed molecular clock analyses indicate that these lineages diverged in the Early Cretaceous, about 140 Ma. The discovery adds a major branch to the amphibian tree of life and sheds light on both the evolution and biogeography of caecilians and the biotic history of northeast India—an area generally interpreted as a gateway between biodiversity hotspots rather than a distinct biogeographic unit with its own ancient endemics. Because of its distinctive morphology, inferred age and phylogenetic relationships, we recognize the newly discovered caecilian radiation as a new family of modern amphibians.

The enigmatic groundwater amphipod Awacaris kawasawai revisited: synonymisation of the genus Sternomoera, with molecular phylogenetic analyses of Awacaris and Sternomoera species (Crustacea : Amphipoda : Pontogeneiidae)

2017 ◽  
Vol 31 (2) ◽  
pp. 125 ◽  
Author(s):  
Ko Tomikawa ◽  
Masaki Kyono ◽  
Keiko Kuribayashi ◽  
Takafumi Nakano
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Analyses ◽  
Taxonomic Status ◽  
28S Rrna ◽  
Ancestral State ◽  
Cryptic Diversity ◽  
Japanese Archipelago ◽  
Molecular Phylogenetic ◽  
The Japanese Archipelago ◽  
Kochi Prefecture

Amphipod crustaceans are dominant in subterranean habitats, and members of eight genera are endemic to groundwater environments in the Japanese Archipelago. The taxonomic status of two of these genera remains unclear, because their original descriptions were incomplete. The descriptions of the enigmatic subterranean monotypic genus Awacaris and its type species, A. kawasawai Uéno, 1971, are revisited here. Awacaris kawasawai was originally described based on specimens from a subterranean stream at Himise Cave, Tokushima Prefecture, Shikoku, Japan. Recently, a new population of A. kawasawai was found at Saruta Cave, Kochi Prefecture, Shikoku. Detailed observation of the newly collected specimens reveals the presence of sternal gills, which is the diagnostic character of the pontogeneiid genus Sternomoera, making the validity of Sternomoera open to question. Phylogenetic analyses using nuclear 28S rRNA and mitochondrial cytochrome c oxidase subunit I markers demonstrate that A. kawasawai forms a well-supported clade with the subterranean S. morinoi Tomikawa and Ishimaru, 2014. In addition, phylogenetic analysis reveals cryptic diversity in epigean species of Sternomoera. Ancestral state reconstruction suggests that catadromous Sternomoera species have evolved from freshwater ancestors. Based on our morphological and phylogenetic analysis of Awacaris and Sternomoera species, it is concluded here that Sternomoera should be treated as a subjective junior synonym of Awacaris.

A molecular phylogeny of the circum-Antarctic Opiliones family Neopilionidae

2021 ◽  
Author(s):  
Gonzalo Giribet ◽  
Kate Sheridan ◽  
Caitlin M. Baker ◽  
Christina J. Painting ◽  
Gregory I. Holwell ◽  
...  
Keyword(s):  
New Zealand ◽  
South America ◽  
Morphological Study ◽  
18S Rrna ◽  
New Caledonia ◽  
Sister Group ◽  
28S Rrna ◽  
South American ◽  
Australian Species ◽  
The Family

The Opiliones family Neopilionidae is restricted to the terranes of the former temperate Gondwana: South America, Africa, Australia, New Caledonia and New Zealand. Despite decades of morphological study of this unique fauna, it has been difficult reconciling the classic species of the group (some described over a century ago) with recent cladistic morphological work and previous molecular work. Here we attempted to investigate the pattern and timing of diversification of Neopilionidae by sampling across the distribution range of the family and sequencing three markers commonly used in Sanger-based approaches (18S rRNA, 28S rRNA and cytochrome-c oxidase subunit I). We recovered a well-supported and stable clade including Ballarra (an Australian ballarrine) and the Enantiobuninae from South America, Australia, New Caledonia and New Zealand, but excluding Vibone (a ballarrine from South Africa). We further found a division between West and East Gondwana, with the South American Thrasychirus/Thrasychiroides always being sister group to an Australian–Zealandian (i.e. Australia + New Zealand + New Caledonia) clade. Resolution of the Australian–Zealandian taxa was analysis-dependent, but some analyses found Martensopsalis, from New Caledonia, as the sister group to an Australian–New Zealand clade. Likewise, the species from New Zealand formed a clade in some analyses, but Mangatangi often came out as a separate lineage from the remaining species. However, the Australian taxa never constituted a monophyletic group, with Ballarra always segregating from the remaining Australian species, which in turn constituted 1–3 clades, depending on the analysis. Our results identify several generic inconsistencies, including the possibility of Thrasychiroides nested within Thrasychirus, Forsteropsalis being paraphyletic with respect to Pantopsalis, and multiple lineages of Megalopsalis in Australia. In addition, the New Zealand Megalopsalis need generic reassignment: Megalopsalis triascuta will require its own genus and M. turneri is here transferred to Forsteropsalis, as Forsteropsalis turneri (Marples, 1944), comb. nov.

Morphological and molecular characterisation of Helicotylenchus ciceri n. sp. and H. scoticus Boag & Jairajpuri, 1985 (Nematoda: Hoplolaimidae) from Iran

Nematology ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. 611-626
Author(s):  
Fariba Mohammadi Zameleh ◽  
Akbar Karegar ◽  
Reza Ghaderi ◽  
Abbas Mokaram Hesar
Keyword(s):  
New Species ◽  
Excretory Pore ◽  
18S Rrna ◽  
Phylogenetic Analyses ◽  
Rrna Genes ◽  
28S Rrna ◽  
Molecular Characterisation ◽  
Closely Related Species ◽  
Partial 18S ◽  
Molecular Characters

Summary Helicotylenchus ciceri n. sp. and H. scoticus are described and illustrated based on morphological, morphometric and molecular characters. The new species is characterised by a conical and truncated lip region with five or six distinct annuli, stylet 32-37 μm long with anteriorly concave knobs, secretory-excretory pore posterior to the pharyngo-intestinal valve, dorsally convex-conoid tail with a terminal projection, phasmids 14 (7-20) annuli anterior to the level of anus, empty spermatheca and absence of males. Intraspecific variation of 16 populations of H. scoticus, collected from chickpea and lentil fields in Kermanshah province, western Iran, is discussed. The results of the phylogenetic analyses based on the sequences of the partial 18S rRNA, D2-D3 expansion segments of 28S rRNA and ITS rRNA genes are provided for the studied species, confirming their differences from each other and determining the position of them and their relationships with closely related species.

scholarly journals Speciation in the genera Anthericum and Chlorophytum (Asparagaceae) in Ethiopia—a molecular phylogenetic approach

Phytotaxa ◽  
2017 ◽  
Vol 297 (2) ◽  
pp. 139 ◽  
Author(s):  
Charlotte Sletten Bjorå ◽  
MARTE ELDEN ◽  
INGER NORDAL ◽  
ANNE K. BRYSTING ◽  
TESFAYE AWAS ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
Molecular Data ◽  
Group Relations ◽  
Variation Patterns ◽  
Molecular Phylogenetic ◽  
Lowland Area ◽  
A New Species ◽  
Scanning Electron

Sister group relations of Ethiopian species of Anthericum and Chlorophytum and variation patterns in the C. gallabatense and C. comosum complexes were studied using molecular phylogenetic analyses, morphometrics, and scanning electron microscopy of seed surfaces. Results indicate that molecular data largely support previous morphological conclusions, and that speciation has occurred in Ethiopia at least three times in Anthericum and repeatedly within different subclades of Chlorophytum. Areas particularly rich in endemic species are the lowland area around Bale Mountains in SE Ethiopia and in the Beninshangul Gumuz regional state in W Ethiopia near the border to Sudan. A new species, Chlorophytum mamillatum Elden & Nordal, is described, and the names C. tordense and C. tetraphyllum are re-instated.

Phylogenetic relationships of Australian Scirtidae (Coleoptera) based on mitochondrial and nuclear sequences

2014 ◽  
Vol 28 (6) ◽  
pp. 628 ◽  
Author(s):  
Steven J. B. Cooper ◽  
Christopher H. S. Watts ◽  
Kathleen M. Saint ◽  
Remko Leijs
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Elongation Factor ◽  
Nuclear Gene ◽  
Species Complexes ◽  
Close Relationship ◽  
Molecular Phylogenetic ◽  
Coi Sequences ◽  
Elongation Factor 1 ◽  
Combined Data

Scirtidae is a cosmopolitan group of beetles with aquatic or saproxylic larvae. A large diversity of species has recently been described from Australia, but their systematics is uncertain. There is evidence that current genera are polyphyletic and that Australian species were wrongly placed in northern hemisphere genera. Here we investigate the systematics of Australian Scirtidae using molecular phylogenetic analyses of combined data from the mitochondrial cytochrome c oxidase subunit 1 (COI) and nuclear gene elongation factor 1-α (EF1-α) genes. We also assess the current taxonomy of Australian Scirtidae using partial COI sequences. Bayesian phylogenetic analyses of COI and EF1-α sequence data from 81 taxa show that the Australian genera Contacyphon, Pseudomicrocara and Prionocyphon are polyphyletic. There is no close relationship between Australian and Eurasian genera, with the exception of Scirtes. Phylogenetic analyses of partial COI data from Australian Scirtidae generally support the current α taxonomy, with the exception of several species that may be associated with species complexes. Geographically a high proportion of species lineages are restricted to relict patches of wet forest suggesting that they may be relict populations. The phylogeny and sequence data presented here provide a sound basis for further systematic and biogeographical studies of the Scirtidae.

scholarly journals The Bacterial Community in the Gut of the Cockroach Shelfordella lateralis Reflects the Close Evolutionary Relatedness of Cockroaches and Termites

2012 ◽  
Vol 78 (8) ◽  
pp. 2758-2767 ◽  
Author(s):  
Christine Schauer ◽  
Claire L. Thompson ◽  
Andreas Brune
Keyword(s):  
Bacterial Community ◽  
Phylogenetic Analyses ◽  
Rflp Analysis ◽  
Sister Group ◽  
Rrna Gene ◽  
Content Type ◽  
Evolutionary Relatedness ◽  
Termite Gut ◽  
Molecular Phylogenetic ◽  
Metabolic Activities

ABSTRACTTermites and cockroaches are closely related, with molecular phylogenetic analyses even placing termites within the radiation of cockroaches. The intestinal tract of wood-feeding termites harbors a remarkably diverse microbial community that is essential for the digestion of lignocellulose. However, surprisingly little is known about the gut microbiota of their closest relatives, the omnivorous cockroaches. Here, we present a combined characterization of physiological parameters, metabolic activities, and bacterial microbiota in the gut ofShelfordella lateralis, a representative of the cockroach family Blattidae, the sister group of termites. We compared the bacterial communities within each gut compartment using terminal-restriction fragment length polymorphism (T-RFLP) analysis and made a 16S rRNA gene clone library of the microbiota in the colon—the dilated part of the hindgut with the highest density and diversity of bacteria. The colonic community was dominated by members of theBacteroidetes,Firmicutes(mainlyClostridia), and someDeltaproteobacteria. SpirochaetesandFibrobacteres, which are abundant members of termite gut communities, were conspicuously absent. Nevertheless, detailed phylogenetic analysis revealed that many of the clones from the cockroach colon clustered with sequences previously obtained from the termite gut, which indicated that the composition of the bacterial community reflects at least in part the phylogeny of the host.

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