scholarly journals Phylogenetic Relatedness within the Internally Brooding Sea Anemones from the Arctic-Boreal Region

Biology ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 81
Author(s):  
Anita Kaliszewicz ◽  
Ninel Panteleeva ◽  
Magdalena Żmuda-Baranowska ◽  
Karol Szawaryn ◽  
Izabella Olejniczak ◽  
...  

Phylogenetic analyses based on mitochondrial 16S rDNA, nuclear 28S rDNA, and morphological and ecological traits of Aulactinia, Urticina and Cribrinopsis sea anemones inhabiting the Arctic-boreal region indicate discordances between trees derived from molecular sequences and those based on morphological traits. Nuclear genes were more informative than mitochondrial and morphological datasets. Our findings indicate that 16S rDNA has limited applicability for phylogenetic analyses at lower taxonomic levels and can only be used for distinction of families. Although 28S rDNA allowed for the classification of distinct genera, it could not confirm that species of Urticina and Cribrinopsis, which appeared to be closely related, were correctly separated into two different genera. The nuclear tree revealed inconsistencies between specimens belonging to European Urticina crassicornis and Pacific U. crassicornis; the latter seems to be a different species. In contrast to Pacific U. crassicornis, the specimens collected from different localities in the Barents Sea are on the same tree branch. The same was observed for specimens of Aulactinia stella. Both species brood their young internally. The dispersal of sea anemones with brooding juveniles seems to be less limited than expected and might be sufficient to settle habitats more than a thousand kilometers away.


2021 ◽  
Vol 9 (08) ◽  
pp. 505-514
Author(s):  
Nguyen Chi Mai ◽  
◽  
NinhThi Ngoc ◽  
Nguyen Xuan Cuong ◽  
Nguyen Hoai Nam ◽  
...  

Vietnam contains diverse marine ecosystems with the high biodiversity of marine organisms, including gorgonian corals of Alcyonacea order. In order to support traditional classification of these corals, in this study mitochondrial barcoding markers msh1 and nuclear 28S rDNA were developed for analysis of 11 specimens collected in 2015 and 2016 from different islands and bays along the North Central coast of Vietnam. Phylogenetic analyses based on msh1 and 28S sequence polymorphism showed that all specimens belonged to Anthozoa class, Octocorallia sub-class and Alcyonacea order. At lower taxa levels, they were divided into 4 sub-orders, 7 families and 7 genera according to 7 distinct clades with bootstrap values from 99-100%.The identifications of 7 out of 11 specimens including Sinularia brassica (2 specimens)and Sinularialeptoclados, Dichotellagemmacea, Annella reticulata, S. conferta and S. nanolobata were in concordance between morphological and molecular methods. The other 4 specimens were only identified at genus levels of Astrogorgia sp., Melithaea sp. Scleronephthya sp. and Muricella sp. by either msh1-morphology or msh1-28S markers. These results highlight the importance of molecular markers to elucidate patterns of biodiversity and species identification of soft coral.



2020 ◽  
Author(s):  
Steffen Aagaard-Sørensen ◽  
Thomas Haugland Johansen ◽  
Juho Junttila

<p>Foraminifera are microscopic single-celled organisms, ubiquitous to the marine realm, that construct shells during their life cycle. The shells, in general, fossilize well in the sediment and they are diagnosable due to inter-species morphology and ornamentation variability. Classifying and counting foraminiferal shells is an important tool in assessing and reconstructing past and present environmental, oceanographic and climatological conditions. However, the present day manual identification procedure, performed with a microscope and a needle/brush, is a very time consuming. Circumventing this manual procedure, using machine leaning, promises to dramatically lower the time consumption related to generating foraminiferal data records.</p><p>The first step towards that end is developing a deep learning model that can detect and classify microscopic foraminifera from 2D digital microscope pictures. The work is based on a VGG16 model implementation that has been pre trained on the ImageNet dataset and employing transfer learning techniques to adapt the model to the foraminifera task. The 2D photographic training data input was constructed by combining objects representative of and extracted from Arctic marine sediments (100µm-1mm size fraction) from the Barents Sea region. Four object groups, including 1) calcareous and 2) agglutinated benthic foraminifera, 3) planktic foraminifera and 4) sediments were used in the training data construction. With the initial set-up the algorithms were able to identify adherence to one of the four groups correctly ~90% of the time and with further fine-tuning and refinement reaching 98% correct identifications.</p><p>The second step is to use machine leaning for classification of individual benthic calcareous foraminiferal species within the sediment. The work will focus on the 20 most common species that comprise ca. ≥ 80% of the total benthic calcareous foraminiferal fauna in the Arctic. The training of the algorithms will be done using targeted species-specific 2D photographic and 3D CT scanning data in addition to potentially using hyperspectral imaging.</p>



2012 ◽  
Vol 26 (3) ◽  
pp. 303 ◽  
Author(s):  
Marcelo V. Kitahara ◽  
Jaroslaw Stolarski ◽  
Stephen D. Cairns ◽  
Francesca Benzoni ◽  
Joel L. Stake ◽  
...  

Dactylotrochus cervicornis (= Tridacophyllia cervicornis Moseley, 1881), which occurs in Indo-Pacific waters between 73 and 852 m, was originally described as an astraeid but was later transferred to the Caryophylliidae. Assumed to be solitary, this species has no stolons and only one elongated fossa, and is unique among azooxanthellate scleractinians in often displaying extremely long thecal extensions that are septate and digitiform. Based on both molecular phylogenetic analyses (partial mitochondrial CO1 and 16S rDNA, and partial nuclear 28S rDNA) and morphological characteristics, we propose the transfer of D. cervicornis from the Caryophylliidae to the Agariciidae, making it the first extant representative of the latter family that is solitary and from deep water (azooxanthellate). The basal position of D. cervicornis within the agariciids implied by our analyses strengthens the case for inclusion of fossil species that were solitary, such as Trochoseris, in this family and suggests that the ancestor of this scleractinian family, extant members of which are predominantly colonial and zooxanthellate, may have been solitary and azooxanthellate.



2007 ◽  
Vol 21 (3) ◽  
pp. 279 ◽  
Author(s):  
Kevin C. Holston ◽  
Michael E. Irwin ◽  
Brian M. Wiegmann

Phylogenetic analyses using 28S rDNA, elongation factor (EF)-1α, and mt 16S rDNA sequences were performed to test the monophyly of Thereva Latreille. Two of the three Afrotropical Thereva species groups lack the genitalia characters that unambiguously diagnose Thereva in the Holarctic Region, but phylogenetic relationships among Thereva species groups and therevine genera are poorly understood. Using an extensive taxonomic sample (39 of the 62 therevine genera) and Thereva, sensu lato (15 spp.), simultaneous analyses of all three gene partitions recovered Nearctic and Palaearctic Thereva species in a well supported clade that includes the Afrotropical seminitida-group but excludes the Afrotropical analis- and turneri-groups. Stronger phylogenetic signal from the EF-1α partition, measured by the skewness statistic and proportion of total parsimony informative characters, dominated conflicting signal from the 16S partition and weaker, but more congruent, signal from 28S. Reducing the taxonomic sample in analyses of Therevinae reduced homoplasy, increased phylogenetic structure and partitioned Bremer support values and reduced incongruence with 28S for the 16S partition. Although molecular analyses yielded partial recovery of informal therevine genus-groups, morphological diagnoses of higher-level groups are poorly supported with the exception of Cyclotelini. The ‘Holarctic radiation’ refers to a diverse clade of genera closely related to Pandivirilia Irwin & Lyneborg and Acrosathe Irwin & Lyneborg widely distributed throughout the Holarctic Region that is the sister-group to Thereva, sensu stricto. Results from these analyses underscore the importance of male and female genitalia characters in recognising monophyletic groups and regional endemism in therevine diversification.



Author(s):  
Paulyn Cartwright ◽  
Nathaniel M. Evans ◽  
Casey W. Dunn ◽  
Antonio C. Marques ◽  
Maria Pia Miglietta ◽  
...  

Hydroidolina is a group of hydrozoans that includes Anthoathecata, Leptothecata and Siphonophorae. Previous phylogenetic analyses show strong support for Hydroidolina monophyly, but the relationships between and within its subgroups remain uncertain. In an effort to further clarify hydroidolinan relationships, we performed phylogenetic analyses on 97 hydroidolinan taxa, using DNA sequences from partial mitochondrial 16S rDNA, nearly complete nuclear 18S rDNA and nearly complete nuclear 28S rDNA. Our findings are consistent with previous analyses that support monophyly of Siphonophorae and Leptothecata and do not support monophyly of Anthoathecata nor its component subgroups, Filifera and Capitata. Instead, within Anthoathecata, we find support for four separate filiferan clades and two separate capitate clades (Aplanulata and Capitatasensu stricto). Our data however, lack any substantive support for discerning relationships between these eight distinct hydroidolinan clades.



Polar Biology ◽  
2012 ◽  
Vol 35 (12) ◽  
pp. 1911-1919 ◽  
Author(s):  
Anita Kaliszewicz ◽  
Ninel Panteleeva ◽  
Izabella Olejniczak ◽  
Paweł Boniecki ◽  
Marek Sawicki


2004 ◽  
Vol 54 (3) ◽  
pp. 961-968 ◽  
Author(s):  
Einat Zchori-Fein ◽  
Steve J. Perlman ◽  
Suzanne E. Kelly ◽  
Nurit Katzir ◽  
Martha S. Hunter

Previously, analysis of 16S rDNA sequences placed a newly discovered lineage of bacterial symbionts of arthropods in the ‘Bacteroidetes’. This symbiont lineage is associated with a number of diverse host reproductive manipulations, including induction of parthenogenesis in several Encarsia parasitoid wasps (Hymenoptera: Aphelinidae). In this study, electron microscopy and phylogenetic analysis of the 16S rRNA and gyrB genes of symbionts from Encarsia hispida and Encarsia pergandiella are used to describe and further characterize these bacteria. Phylogenetic analyses based on these two genes showed that the Encarsia symbionts are allied with the Cytophaga aurantiaca lineage within the ‘Bacteroidetes’, with their closest described relative being the acanthamoeba symbiont ‘Candidatus Amoebophilus asiaticus’. The Encarsia symbionts share 97 % 16S rDNA sequence similarity with Brevipalpus mite and Ixodes tick symbionts and 88 % sequence similarity with ‘Candidatus A. asiaticus’. Electron microscopy revealed that many of the bacteria found in the ovaries of the two Encarsia species contained a regular, brush-like array of microfilament-like structures that appear to be characteristic of the symbiont. Finally, the role of this bacterium in parthenogenesis induction in E. hispida was confirmed. Based on phylogenetic analyses and electron microscopy, classification of the symbionts from Encarsia as ‘Candidatus Cardinium hertigii’ is proposed.



Author(s):  
Larisa A. Pautova ◽  
Vladimir A. Silkin ◽  
Marina D. Kravchishina ◽  
Valeriy G. Yakubenko ◽  
Anna L. Chultsova

The structure of the summer planktonic communities of the Northern part of the Barents sea in the first half of August 2017 were studied. In the sea-ice melting area, the average phytoplankton biomass producing upper 50-meter layer of water reached values levels of eutrophic waters (up to 2.1 g/m3). Phytoplankton was presented by diatoms of the genera Thalassiosira and Eucampia. Maximum biomass recorded at depths of 22–52 m, the absolute maximum biomass community (5,0 g/m3) marked on the horizon of 45 m (station 5558), located at the outlet of the deep trench Franz Victoria near the West coast of the archipelago Franz Josef Land. In ice-free waters, phytoplankton abundance was low, and the weighted average biomass (8.0 mg/m3 – 123.1 mg/m3) corresponded to oligotrophic waters and lower mesotrophic waters. In the upper layers of the water population abundance was dominated by small flagellates and picoplankton from, biomass – Arctic dinoflagellates (Gymnodinium spp.) and cold Atlantic complexes (Gyrodinium lachryma, Alexandrium tamarense, Dinophysis norvegica). The proportion of Atlantic species in phytoplankton reached 75%. The representatives of warm-water Atlantic complex (Emiliania huxleyi, Rhizosolenia hebetata f. semispina, Ceratium horridum) were recorded up to 80º N, as indicators of the penetration of warm Atlantic waters into the Arctic basin. The presence of oceanic Atlantic species as warm-water and cold systems in the high Arctic indicates the strengthening of processes of “atlantificacion” in the region.



Author(s):  
Yu.V. Razovsky ◽  
◽  
M.S. Ruban ◽  
E.Yu. Gorenkova ◽  
◽  
...  
Keyword(s):  


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Parisa Soltan-Alinejad ◽  
Javad Rafinejad ◽  
Farrokh Dabiri ◽  
Piero Onorati ◽  
Olle Terenius ◽  
...  

Abstract Objectives Annually, 1.2 million humans are stung by scorpions and severely affected by their venom. Some of the scorpion species of medical importance have a similar morphology to species with low toxicity. To establish diagnostic tools for surveying scorpions, the current study was conducted to generate three mitochondrial markers, Cytochrome Oxidase I (COI gene), 12S rDNA and 16S rDNA for six species of medically important Iranian scorpions: Androctonus crassicauda, Hottentotta saulcyi, Mesobuthus caucasicus, M. eupeus, Odontobuthus doriae, and Scorpio maurus. Results Phylogenetic analyses of the obtained sequences corroborated the morphological identification. For the first time, 12S rDNA sequences are reported from Androctonus crassicauda, Hottentotta saulcyi, Mesobuthus caucasicus and M. eupeus and also the 16S rDNA sequence from Hottentotta saulcyi. We conclude that the mitochondrial markers are useful for species determination among these medically important species of scorpions.



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