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Molecular Data and the Evolutionary History of Dinoflagellates by Juan Fernando Saldarriaga Echavarria Diplom, Ruprecht-Karls-Un
Molecular data and the evolutionary history of dinoflagellates by Juan Fernando Saldarriaga Echavarria Diplom, Ruprecht-Karls-Universitat Heidelberg, 1993 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES Department of Botany We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA November 2003 © Juan Fernando Saldarriaga Echavarria, 2003 ABSTRACT New sequences of ribosomal and protein genes were combined with available morphological and paleontological data to produce a phylogenetic framework for dinoflagellates. The evolutionary history of some of the major morphological features of the group was then investigated in the light of that framework. Phylogenetic trees of dinoflagellates based on the small subunit ribosomal RNA gene (SSU) are generally poorly resolved but include many well- supported clades, and while combined analyses of SSU and LSU (large subunit ribosomal RNA) improve the support for several nodes, they are still generally unsatisfactory. Protein-gene based trees lack the degree of species representation necessary for meaningful in-group phylogenetic analyses, but do provide important insights to the phylogenetic position of dinoflagellates as a whole and on the identity of their close relatives. Molecular data agree with paleontology in suggesting an early evolutionary radiation of the group, but whereas paleontological data include only taxa with fossilizable cysts, the new data examined here establish that this radiation event included all dinokaryotic lineages, including athecate forms. Plastids were lost and replaced many times in dinoflagellates, a situation entirely unique for this group. Histones could well have been lost earlier in the lineage than previously assumed. -
Patrons De Biodiversité À L'échelle Globale Chez Les Dinoflagellés
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emerciements* ! Remerciements* A!l'issue!de!ce!travail!de!recherche!et!de!sa!rédaction,!j’ai!la!preuve!que!la!thèse!est!loin!d'être!un!travail! solitaire.! En! effet,! je! n'aurais! jamais! pu! réaliser! ce! travail! doctoral! sans! le! soutien! d'un! grand! nombre! de! personnes!dont!l’amitié,!la!générosité,!la!bonne!humeur%et%l'intérêt%manifestés%à%l'égard%de%ma%recherche%m'ont% permis!de!progresser!dans!cette!phase!délicate!de!«!l'apprentiGchercheur!».! -
Pliocene-Pleistocene Calcareous Nannofossil Biostratigraphy of Iodp
Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2013 Pliocene-Pleistocene Calcareous Nannofossil Biostratigraphy of IODP Hole 1396C Adjacent to Montserrat Island in the Lesser Antilles, Caribbean Sea, Plus Experimentally Induced Diagenesis Mohammed H. Aljahdali Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES PLIOCENE-PLEISTOCENE CALCAREOUS NANNOFOSSIL BIOSTRATIGRAPHY OF IODP HOLE 1396C ADJACENT TO MONTSERRAT ISLAND IN THE LESSER ANTILLES, CARIBBEAN SEA, PLUS EXPERIMENTALLY INDUCED DIAGENESIS By MOHAMMED H. ALJAHDALI A Thesis submitted to the Department of Earth, Ocean and Atmospheric Sciences in partial fulfillment of the requirements for the Degree of Master of Science Degree Awarded: Spring Semester 2013 Mohammed H. Aljahdali defended this thesis on March 27, 2013. The members of the supervisory committee were: Sherwood W. Wise, Jr. Professor Directing Thesis Yang Wang Committee Member William Parker Committee Member The Graduate School has verified and approved the above-named committee members, and certifies that this thesis has been approved in accordance with university requirements. ii Dedicated To my family whose support has made this project possible. iii ACKNOWLEDGMENTS First of all, I would like to thank and express my gratitude to my major advisor Professor Sherwood “Woody” Wise for his encouragement and suggestion that made this work valuable. Woody introduced me to the Nannofossil micropaleontology field back in 2010 when I was looking for an advisor to work within the foraminifera field. I took classes in his lab with almost no idea about what nannofossils were. -
A Parasite of Marine Rotifers: a New Lineage of Dinokaryotic Dinoflagellates (Dinophyceae)
Hindawi Publishing Corporation Journal of Marine Biology Volume 2015, Article ID 614609, 5 pages http://dx.doi.org/10.1155/2015/614609 Research Article A Parasite of Marine Rotifers: A New Lineage of Dinokaryotic Dinoflagellates (Dinophyceae) Fernando Gómez1 and Alf Skovgaard2 1 Laboratory of Plankton Systems, Oceanographic Institute, University of Sao˜ Paulo, Prac¸a do Oceanografico´ 191, Cidade Universitaria,´ 05508-900 Butanta,˜ SP, Brazil 2Department of Veterinary Disease Biology, University of Copenhagen, Stigbøjlen 7, 1870 Frederiksberg C, Denmark Correspondence should be addressed to Fernando Gomez;´ [email protected] Received 11 July 2015; Accepted 27 August 2015 Academic Editor: Gerardo R. Vasta Copyright © 2015 F. Gomez´ and A. Skovgaard. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Dinoflagellate infections have been reported for different protistan and animal hosts. We report, for the first time, the association between a dinoflagellate parasite and a rotifer host, tentatively Synchaeta sp. (Rotifera), collected from the port of Valencia, NW Mediterranean Sea. The rotifer contained a sporangium with 100–200 thecate dinospores that develop synchronically through palintomic sporogenesis. This undescribed dinoflagellate forms a new and divergent fast-evolved lineage that branches amongthe dinokaryotic dinoflagellates. 1. Introduction form independent lineages with no evident relation to other dinoflagellates [12]. In this study, we describe a new lineage of The alveolates (or Alveolata) are a major lineage of protists an undescribed parasitic dinoflagellate that largely diverged divided into three main phyla: ciliates, apicomplexans, and from other known dinoflagellates. -
Coccolithophore Distribution in the Mediterranean Sea and Relate A
Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Ocean Sci. Discuss., 11, 613–653, 2014 Open Access www.ocean-sci-discuss.net/11/613/2014/ Ocean Science OSD doi:10.5194/osd-11-613-2014 Discussions © Author(s) 2014. CC Attribution 3.0 License. 11, 613–653, 2014 This discussion paper is/has been under review for the journal Ocean Science (OS). Coccolithophore Please refer to the corresponding final paper in OS if available. distribution in the Mediterranean Sea Is coccolithophore distribution in the A. M. Oviedo et al. Mediterranean Sea related to seawater carbonate chemistry? Title Page Abstract Introduction A. M. Oviedo1, P. Ziveri1,2, M. Álvarez3, and T. Tanhua4 Conclusions References 1Institute of Environmental Science and Technology (ICTA), Universitat Autonoma de Barcelona (UAB), 08193 Bellaterra, Spain Tables Figures 2Earth & Climate Cluster, Department of Earth Sciences, FALW, Vrije Universiteit Amsterdam, FALW, HV1081 Amsterdam, the Netherlands J I 3IEO – Instituto Espanol de Oceanografia, Apd. 130, A Coruna, 15001, Spain 4GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel, Marine Biogeochemistry, J I Duesternbrooker Weg 20, 24105 Kiel, Germany Back Close Received: 31 December 2013 – Accepted: 15 January 2014 – Published: 20 February 2014 Full Screen / Esc Correspondence to: A. M. Oviedo ([email protected]) Published by Copernicus Publications on behalf of the European Geosciences Union. Printer-friendly Version Interactive Discussion 613 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Abstract OSD The Mediterranean Sea is considered a “hot-spot” for climate change, being char- acterized by oligotrophic to ultra-oligotrophic waters and rapidly changing carbonate 11, 613–653, 2014 chemistry. Coccolithophores are considered a dominant phytoplankton group in these 5 waters. -
Understanding Bioluminescence in Dinoflagellates—How Far Have We Come?
Microorganisms 2013, 1, 3-25; doi:10.3390/microorganisms1010003 OPEN ACCESS microorganisms ISSN 2076-2607 www.mdpi.com/journal/microorganisms Review Understanding Bioluminescence in Dinoflagellates—How Far Have We Come? Martha Valiadi 1,* and Debora Iglesias-Rodriguez 2 1 Department of Evolutionary Ecology, Max Planck Institute for Evolutionary Biology, August-Thienemann-Strasse, Plӧn 24306, Germany 2 Department of Ecology, Evolution and Marine Biology, University of California Santa Barbara, Santa Barbara, CA 93106, USA; E-Mail: [email protected] * Author to whom correspondence should be addressed; E-Mail: [email protected] or [email protected]; Tel.: +49-4522-763277; Fax: +49-4522-763310. Received: 3 May 2013; in revised form: 20 August 2013 / Accepted: 24 August 2013 / Published: 5 September 2013 Abstract: Some dinoflagellates possess the remarkable genetic, biochemical, and cellular machinery to produce bioluminescence. Bioluminescent species appear to be ubiquitous in surface waters globally and include numerous cosmopolitan and harmful taxa. Nevertheless, bioluminescence remains an enigmatic topic in biology, particularly with regard to the organisms’ lifestyle. In this paper, we review the literature on the cellular mechanisms, molecular evolution, diversity, and ecology of bioluminescence in dinoflagellates, highlighting significant discoveries of the last quarter of a century. We identify significant gaps in our knowledge and conflicting information and propose some important research questions -
Is Coccolithophore Distribution in the Mediterranean Sea Related to Seawater Carbonate Chemistry? A
Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Ocean Sci. Discuss., 11, 613–653, 2014 Open Access www.ocean-sci-discuss.net/11/613/2014/ Ocean Science doi:10.5194/osd-11-613-2014 Discussions © Author(s) 2014. CC Attribution 3.0 License. This discussion paper is/has been under review for the journal Ocean Science (OS). Please refer to the corresponding final paper in OS if available. Is coccolithophore distribution in the Mediterranean Sea related to seawater carbonate chemistry? A. M. Oviedo1, P. Ziveri1,2, M. Álvarez3, and T. Tanhua4 1Institute of Environmental Science and Technology (ICTA), Universitat Autonoma de Barcelona (UAB), 08193 Bellaterra, Spain 2Earth & Climate Cluster, Department of Earth Sciences, FALW, Vrije Universiteit Amsterdam, FALW, HV1081 Amsterdam, the Netherlands 3IEO – Instituto Espanol de Oceanografia, Apd. 130, A Coruna, 15001, Spain 4GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel, Marine Biogeochemistry, Duesternbrooker Weg 20, 24105 Kiel, Germany Received: 31 December 2013 – Accepted: 15 January 2014 – Published: 20 February 2014 Correspondence to: A. M. Oviedo ([email protected]) Published by Copernicus Publications on behalf of the European Geosciences Union. 613 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Abstract The Mediterranean Sea is considered a “hot-spot” for climate change, being char- acterized by oligotrophic to ultra-oligotrophic waters and rapidly changing carbonate chemistry. Coccolithophores are considered a dominant phytoplankton group in these 5 waters. As a marine calcifying organism they are expected to respond to the ongo- ing changes in seawater CO2 systems parameters. However, very few studies have covered the entire Mediterranean physiochemical gradients from the Strait of Gibral- tar to the Eastern Mediterranean Levantine Basin. -
The Windblown: Possible Explanations for Dinophyte DNA
bioRxiv preprint doi: https://doi.org/10.1101/2020.08.07.242388; this version posted August 10, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. The windblown: possible explanations for dinophyte DNA in forest soils Marc Gottschlinga, Lucas Czechb,c, Frédéric Mahéd,e, Sina Adlf, Micah Dunthorng,h,* a Department Biologie, Systematische Botanik und Mykologie, GeoBio-Center, Ludwig- Maximilians-Universität München, D-80638 Munich, Germany b Computational Molecular Evolution Group, Heidelberg Institute for Theoretical Studies, D- 69118 Heidelberg, Germany c Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA d CIRAD, UMR BGPI, F-34398, Montpellier, France e BGPI, Université de Montpellier, CIRAD, IRD, Montpellier SupAgro, Montpellier, France f Department of Soil Sciences, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, S7N 5A8, SK, Canada g Eukaryotic Microbiology, Faculty of Biology, Universität Duisburg-Essen, D-45141 Essen, Germany h Centre for Water and Environmental Research (ZWU), Universität Duisburg-Essen, D- 45141 Essen, Germany Running title: Dinophytes in soils Correspondence M. Dunthorn, Eukaryotic Microbiology, Faculty of Biology, Universität Duisburg-Essen, Universitätsstrasse 5, D-45141 Essen, Germany Telephone number: +49-(0)-201-183-2453; email: [email protected] bioRxiv preprint doi: https://doi.org/10.1101/2020.08.07.242388; this version posted August 10, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. -
Phytobase: a Global Synthesis of Open-Ocean Phytoplankton Occurrences
Research Collection Journal Article PhytoBase: A global synthesis of open-ocean phytoplankton occurrences Author(s): Righetti, Damiano; Vogt, Meike; Zimmermann, Niklaus E.; Guiry, Michael D.; Gruber, Nicolas Publication Date: 2020 Permanent Link: https://doi.org/10.3929/ethz-b-000414680 Originally published in: Earth System Science Data 12(2), http://doi.org/10.5194/essd-12-907-2020 Rights / License: Creative Commons Attribution 4.0 International This page was generated automatically upon download from the ETH Zurich Research Collection. For more information please consult the Terms of use. ETH Library Earth Syst. Sci. Data, 12, 907–933, 2020 https://doi.org/10.5194/essd-12-907-2020 © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. PhytoBase: A global synthesis of open-ocean phytoplankton occurrences Damiano Righetti1, Meike Vogt1, Niklaus E. Zimmermann2, Michael D. Guiry3, and Nicolas Gruber1 1Environmental Physics, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Universitätstrasse 16, 8092 Zürich, Switzerland 2Dynamic Macroecology, Landscape Dynamics, Swiss Federal Research Institute WSL, 8903 Birmensdorf, Switzerland 3AlgaeBase, Ryan Institute, NUI, Galway, University Road, Galway H91 TK33, Ireland Correspondence: Damiano Righetti ([email protected]) Received: 3 September 2019 – Discussion started: 14 October 2019 Revised: 24 February 2020 – Accepted: 11 March 2020 – Published: 24 April 2020 Abstract. Marine phytoplankton are responsible for half of the global net primary production and perform mul- tiple other ecological functions and services of the global ocean. These photosynthetic organisms comprise more than 4300 marine species, but their biogeographic patterns and the resulting species diversity are poorly known, mostly owing to severe data limitations. -
Diversidad Del Microfitoplancton En Las Aguas Oceánicas Alrededor De Cuba
DIVERSIDAD DEL MICROFITOPLANCTON EN LAS AGUAS OCEÁNICAS ALREDEDOR DE CUBA Sandra Loza Álvarez1 y Gladys Margarita Lugioyo Gallardo1* RESUMEN Se evalúa la diversidad de la comunidad microfitoplanctónica en las aguas oceánicas alrededor de Cuba durante cuatro cruceros (febrero-marzo de 1999, julio-agosto del 2003, marzo del 2005 y agosto del 2005). Las muestras se recolectaron con botellas Nansen de 10 L de capa- cidad, a nivel subsuperficial y se concentraron mediante filtración invertida, a través de una malla de 20 µm de diámetro de poro. El volumen de agua filtrado por estaciones osciló entre 5 y 10 L. Se reportan un total de 181 especies de microalgas ubicadas en las diferentes categorías taxonómicas. El microfitoplancton estuvo dominado en cuanto al número de especies por dia- tomeas 85 y dinoflagelados 47, seguidas por cianobacterias con 23 especies y las dictiocofitas y primnesiofitas con 23 especies (mayormente cocolitofóridos). De las diatomeas, las familias Bacillariaceae, Chaetoceraceae y Rhizosoleniaceae aportan el mayor número de especies con los géneros Nitzschia, Chaetoceros y Rhizosolenia. En los dinoflagelados se distinguen las familias Ceratiaceae, Protoperidiniaceae y Oxytosaceae y los géneros Ceratium, Protoperidi- nium y Oxytoxum. Las aguas oceánicas al norte de Cuba presentan mayor diversidad de espe- cies (136) con respecto a las del sur (103), como lo demuestra el índice de riqueza (R1) que en el norte fue de 48.35, mientras en el sur fue de 28.19. Palabras claves: Microfitoplancton, diversidad, taxonomía, aguas oceánicas, Cuba. ABSTRACT The structure of the microphytoplankton community was evaluated in oceanic waters around Cuba during four cruises (February-March 1999, July-August 2003, March 2005 and August 2005). -
Attributing Ceratocorys, Pentaplacodinium and Protoceratium to Protoceratiaceae (Dinophyceae), with Descriptions of Ceratocorys Malayensis Sp
1 Phycologia Archimer 2020, Volume 59, Issue 1, Pages 6-23 https://doi.org/10.1080/00318884.2019.1663693 https://archimer.ifremer.fr https://archimer.ifremer.fr/doc/00589/70143/ Attributing Ceratocorys, Pentaplacodinium and Protoceratium to Protoceratiaceae (Dinophyceae), with descriptions of Ceratocorys malayensis sp. nov. and Pentaplacodinium usupianum sp. nov Luo Zhaohe 1 , Lim Zhen Fei 2, Mertens Kenneth 3, Krock Bernd 4, Teng Sing Tung 5, Tan Toh Hii 2, Leaw Chui Pin 2, Lim Po Teen 2, Gu Haifeng 1, * 1 Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China 2 Bachok Marine Research Station, Institute of Ocean and Earth Sciences, University of Malaya, Bachok 16310, Malaysia 3 Ifremer, LER BO, Station de Biologie Marine, Place de la Croix, BP40537, Concarneau CEDEX F- 29185, France 4 Alfred Wegener Institute for Polar and Marine Research, Ecological Chemistry, Am Handelshafen 12, Bremerhaven D-27570, Germany 5 Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan 94300, Malaysia * Corresponding author : Haifeng Gu, email address : [email protected] Abstract : The gonyaulacean family Protoceratiaceae is characterised by five precingular plates. It currently encompasses the type genus Ceratocorys and the fossil genus Atopodinium. Fourteen strains of Ceratocorys, Pentaplacodinium, and Protoceratium were established from Malaysian and Hawaiian waters, and their morphologies were examined using light and scanning electron microscopy. Two new species, Ceratocorys malayensis sp. nov. and Pentaplacodinium usupianum sp. nov., were described from Malaysian waters. They share a Kofoidean plate formula of Po, Pt, 3ʹ, 1a, 6ʹʹ, 6C, 6S, 5ʹʹʹ, 1p, 1ʹʹʹʹ. Ceratocorys malayensis has a short first apical plate (1ʹ) with no direct contact with the anterior sulcal plate (Sa) whereas Pentaplacodinium usupianum had a parallelogram-shaped 1ʹ plate which often contacted the Sa plate. -
Is Karenia a Synonym of Asterodinium-Brachidinium (Gymnodiniales, Dinophyceae)?
Acta Bot. Croat. 64 (2), 263–274, 2005 CODEN: ABCRA25 ISSN 0365–0588 Is Karenia a synonym of Asterodinium-Brachidinium (Gymnodiniales, Dinophyceae)? FERNANDO GÓMEZ1*, YUKIO NAGAHAMA2,HARUYOSHI TAKAYAMA3,KEN FURUYA2 1 Station Marine de Wimereux, Université des Sciences et Technologies de Lille, CNRS UMR 8013 ELICO, 28 avenue Foch, BP 80, F-62930 Wimereux, France. 2 Department of Aquatic Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo 113-8657, Japan. 3 Hiroshima Prefectural Fisheries and Marine Technology Center, Hatami 6-1-21, Ondo-cho, Kure Hiroshima 737-1205, Japan From material collected in open waters of the NW and Equatorial Pacific Ocean the de- tailed morphology of brachidiniaceans based on two specimens of Asterodinium gracile is reported for the first time. SEM observations showed that the straight apical groove, the morphological characters and orientation of the cell body were similar to those described for species of Karenia. Brachidinium and Asterodinium showed high morphological vari- ability in the length of the extensions and intermediate specimens with Karenia. Karenia-like cells that strongly resemble Brachidinium and Asterodinium but lacking the extensions co-occurred with the typical specimens. The life cycle and morphology of Karenia papilionacea should be investigated under natural conditions because of the strong simi- larity with the brachidiniaceans. Key words: Phytoplankton, Asterodinium, Brachidinium, Brachydinium, Gymnodinium, Karenia, Dinophyta, apical groove, SEM, Pacific Ocean. Introduction Fixatives, such as formaline or Lugol, do not sufficiently preserve unarmoured dino- flagellates to allow species identification. Body shape and morphology often change dur- ing the process of fixation so that even differentiating between the genera Gymnodinium Stein and Gyrodinium Kofoid et Swezy is difficult (ELBRÄCHTER 1979).