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Kazumi Matsuoka - One of the best experts on this subject based on the ideXlab platform.

  • taxonomic revision phylogeny and Cyst wall composition of the Dinoflagellate Cyst genus votadinium reid dinophyceae peridiniales protoperidiniaceae
    Palynology, 2020
    Co-Authors: Pieter Gurdebeke, Kenneth Neil Mertens, Vera Pospelova, Kristin E Gribble, Kara Bogus, Haifeng Gu, Kazumi Matsuoka, Zhen Li, Henk Vrielinck
    Abstract:

    The taxonomy of the Dinoflagellate Cyst-based genus Votadinium has been in need of revision. This is accomplished here by integrating morphology, large subunit (LSU) rDNA sequences, and Cyst wall c...

  • Reconstruction of historical nutrient levels in Korean and Japanese coastal areas based on Dinoflagellate Cyst assemblages.
    Marine pollution bulletin, 2010
    Co-Authors: Hyeon Ho Shin, Kazumi Matsuoka, Koichiro Mizushima, Jong Sick Park, Il Hyeon Noh, Mitsunori Iwataki, Yang Ho Yoon
    Abstract:

    Dinoflagellate Cysts acquired from sediment cores were analyzed in order to reconstruct historical nutrient levels in Gamak Bay, Korea and Ariake Bay, Japan. Dinoflagellate Cyst assemblages in Gamak Bay were characterized by high proportions of heterotrophic Cysts such as Brigantedinium spp., Protoperidinium americanum and Polykrikos Cysts, which suggested that nutrients levels may have already been high before 1970s, and then increased further to the hypertrophic conditions of the 1990s. In contrast, Dinoflagellate Cyst assemblages in Ariake Bay were characterized by high relative abundances of Lingulodinium machaerophorum and Spiniferites spp., which suggested that nutrient levels in Ariake Bay had increased gradually since the mid 1960s, and may have been significantly enhanced by the mid 1980s. Dinoflagellate Cyst assemblages reflecting environmental changes in the two bays are contrasting, perhaps due to different nutrient enrichment mechanisms. This suggests that the indicators of nutrient levels encoded in Dinoflagellate Cyst assemblages may exhibit site-specific information.

  • protoperidinium tricingulatum sp nov dinophyceae a new motile form of a round brown and spiny Dinoflagellate Cyst
    Phycological Research, 2009
    Co-Authors: Hisae Kawami, Rene Van Wezel, Reinoud P T Koeman, Kazumi Matsuoka
    Abstract:

    SUMMARY A small, broadly ovoidal and heterotrophic dinoflagel- late containing round, brownish, and spiny Cyst was found in the water column of Huibertsplaat in the Wadden Sea off the coast of the Netherlands. This Dinoflagellate had these conspicuous morphological characters: a five-sided first apical plate (1'), only three cingular plates, and an extremely small first antapical plate. Based on these morphological features, Protope- ridinium tricingulatum Kawami, vanWezel, Koeman et Matsuoka is described as a new species. The flagellar pore of P. tricingulatum is covered with a small fin, which rises from the left side of the right sulcal plate to the large V-shaped posterior sulcal plate. This feature suggests that P. tricingulatum is assigned to the Abe's Monovela Group. The Cyst stage of P. tricingulatum was positively linked to the vegetative stage by comparison of the ribosomal 5.8S rDNA, internal transcribed spacers (ITS1 and ITS2). Living Cysts of P. tricingula- tum are round, brownish, and covered with many slender spines bearing capitate or cauliforate distal ends. The Cyst also possesses a theropylic archeopyle formed by a slit corresponding to parasutures between three apical and two apical intercaraly plates. These morphological characters indicate that this species is morphologically related to two Dinoflagellate Cyst- genera Islandinium and Echinidinium.

  • horizontal Dinoflagellate Cyst distribution sediment characteristics and benthic flux in manila bay philippines
    Phycological Research, 2004
    Co-Authors: Rhodora V. Azanza, Maria Lourdes San Diegomcglone, Neil John H Macalalad, Melissa B Agustin, Peter B. Zamora, Aletta T Yniguez, Fernando P. Siringan, Kazumi Matsuoka
    Abstract:

    SUMMARY The lateral variation of sediment properties and associated Cyst content of sediment in Manila Bay were determined and their possible role/s in the occurrences of Pyrodinium bahamense Plate var. compressum (Bohm) Steidinger, Tester et Taylor toxic blooms were assessed. Manila Bay's surface sediment was determined to be silt dominated. Clay generally increased towards the coast, probably as a result of flocculation and rapid deposition upon entry of sediments from the rivers. High sand content characterized the southeastern part of the bay attributed to the greater sand inputs and relatively strong currents in this area. Bulk densities were lower in the eastern side of the bay from dilution by high organic load from sewage and urban areas. Benthic flux calculations, particularly NH3, suggest more than 50% nutrient contribution comes from sediments. In general, Dinoflagellate Cyst density increased from the center of the bay towards the coast, except in Pampanga Bay where it deceased near the coasts. A maximum of 23 Dinoflagellate species were identified: 5 were autotrophic (Lingulodinium polyedrum (Stein) Dodge, Gonyaulax spp., Pyrophacus steinii (Schiller) Wall et Dale, Protoceratium reticulatum (Claparede et Lachmann) Butschli, and Pyrodinium bahamense var. compressum), and the rest were predominantly composed of Protoperidinium spp. and Diplopsalis spp. Heterotrophs comprised about 70% of the total Cyst counts. Pyrodinium counts increased towards the northwestern part of the bay where it was the dominant autotroph species. Negative correlations were observed for live Pyrodinium Cyst density and N flux, P flux, ratio of N to P and total organic carbon (TOC) content. However, areas with high N:P ratio contain abundant Pyrodinium live Cysts.

  • Eutrophication process recorded in Dinoflagellate Cyst assemblages — a case of Yokohama Port, Tokyo Bay, Japan
    The Science of the total environment, 1999
    Co-Authors: Kazumi Matsuoka
    Abstract:

    To investigate temporal changes of water quality, a role of Dinoflagellate Cysts preserved in surface sediments was examined in Yokohama Port in Tokyo Bay, Japan. Two cores were collected, and sedimentation rates and ages of both were dated as approximately 1900 years or slightly older on the basis of 210Pb and 137Cs concentrations. The temporal change in Dinoflagellate Cyst assemblages in the two cores reflects eutrophication in Yokohama Port in the 1960s. Abrupt increases in the Cysts of Gyrodinium instriatum Cysts strongly suggests that a red tide was caused by this species around 1985. Dinoflagellate Cyst assemblages in surface sediments appear to be good biomarkers of changes in the water quality of enclosed seas.

Fabienne Marret - One of the best experts on this subject based on the ideXlab platform.

  • eemian and holocene sea surface conditions in the southern black sea organic walled Dinoflagellate Cyst record from core 22 gc3
    Marine Micropaleontology, 2013
    Co-Authors: Lyudmila S Shumilovskikh, Fabienne Marret, Dominik Fleitmann, Helge W Arz, Norbert R Nowaczyk, Hermann Behling
    Abstract:

    In order to compare the sea-surface conditions in the Black Sea during the Holocene and Eemian, sapropelic parts of marine core 22-GC3 (42°13.53′N/36°29.55′E, 838 m water depth) were studied for organic-walled Dinoflagellate Cyst content. The record shows a change from freshwater/brackish assemblages (Pyxidinopsis psilata, Spiniferites cruciformis, and Caspidinium rugosum) to more marine assemblages (Lingulodinium machaerophorum and Spiniferites ramosus complex) during each interglacial, due to the inflow of saline Mediterranean water. The lacustrine–marine transitions in 22-GC3 occurred at ~ 8.3 cal kyr BP during the early Holocene and ~ 128 kyr BP during the early Eemian, slightly later compared to the onset of interglacial conditions on the adjacent land. Dinoflagellate Cyst assemblages reveal higher sea-surface salinity (~ 28–30) (e.g. Spiniferites pachydermus, Bitectatodinium tepikiense, and Spiniferites mirabilis) around ~ 126.5–121 kyr BP in comparison to the Holocene (~ 15–20) as well as relatively high sea-surface temperature (e.g. Tuberculodinium vancampoae, S. pachydermus, and S. mirabilis) especially at ~ 127.6–125.3 kyr BP. Establishment of high sea-surface salinity during the Eemian correlates very well with reconstructed relatively high global sea-level and is explained as a combined effect of increased Mediterranean supply and high temperatures at the beginning of the last interglacial. The observed changes in the dinoCyst record highlight the importance of nutrients for the composition of the Eemian and Holocene dinoCyst assemblages.

  • atlas of modern Dinoflagellate Cyst distribution based on 2405 data points
    Review of Palaeobotany and Palynology, 2013
    Co-Authors: Karin A F Zonneveld, Kara Bogus, Fabienne Marret, Anne De Vernal, Erica M Crouch, Ilham Bouimetarhan, Gerard J M Versteegh, Sophie Bonnet, Rehab Elshanawany
    Abstract:

    Dinoflagellate Cysts are useful for reconstructing upper water conditions. For adequate reconstructions detailed information is required about the relationship between modern day environmental conditions and the geographic distribution of Cysts in sediments. This Atlas summarises the modern global distribution of 71 organic-walled Dinoflagellate Cyst species. The synthesis is based on the integration of literature sources together with data of 2405 globally distributed surface sediment samples that have been prepared with a comparable methodology and taxonomy. The distribution patterns of individual Cyst species are being compared with environmental factors that are known to influence Dinoflagellate growth, gamete production, enCystment, exCystment and preservation of their organic-walled Cysts: surface water temperature, salinity, nitrate, phosphate, chlorophyll-a concentrations and bottom water oxygen concentrations. Graphs are provided for every species depicting the relationship between seasonal and annual variations of these parameters and the relative abundance of the species. Results have been compared with previously published records; an overview of the ecological significance as well as information about the seasonal production of each individual species is presented. The relationship between the Cyst distribution and variation in the aforementioned environmental parameters was analysed by performing a canonical correspondence analysis. All tested variables showed a positive relationship on the 99% confidence level. Sea-surface temperature represents the parameter corresponding to the largest amount of variance within the dataset (40%) followed by nitrate, salinity, phosphate and bottom-water oxygen concentration, which correspond to 34%, 33%, 25% and 24% of the variance, respectively. Characterisations of selected environments as well as a discussion about how these factors could have influenced the final Cyst yield in sediments are included.

  • quantitative estimation of holocene surface salinity variation in the black sea using Dinoflagellate Cyst process length
    Quaternary Science Reviews, 2012
    Co-Authors: Kenneth Neil Mertens, Yoshihito Takano, Fabienne Marret, L R Bradley, P J Mudie, A E Aksu, Richard N Hiscott, Thomas Verleye, Erik Askov Mousing
    Abstract:

    Reconstruction of salinity in the Holocene Black Sea has been an ongoing debate over the past four decades. Here we calibrate summer surface water salinity in the Black Sea, Sea of Azov and Caspian Sea with the process length of the Dinoflagellate Cyst Lingulodinium machaerophorum. We then apply this calibration to make a regional reconstruction of paleosalinity in the Black Sea, calculated by averaging out process length variation observedatfourcore sites fromtheBlack Seawithhigh sedimentation rates anddatedbymultiple mollusk shell ages. Results show averygradual change of salinity from w14 � 0.91 psu around 9.9 cal ka BP to a minimum w12.3 � 0.91 psu around 8.5 cal ka BP, reaching current salinities ofw17.1 � 0.91 psu around

  • Dinoflagellate Cyst distribution in marine surface sediments off west africa 17 6 n in relation to sea surface conditions freshwater input and seasonal coastal upwelling
    Marine Micropaleontology, 2009
    Co-Authors: Ilham Bouimetarhan, Fabienne Marret, Lydie M Dupont, Karin A F Zonneveld
    Abstract:

    Abstract An organic-walled Dinoflagellate Cyst analysis was carried out on 53 surface sediment samples from West Africa (17–6°N) to obtain insight in the relationship between their spatial distribution and hydrological conditions in the upper water column as well as marine productivity in the study area. Multivariate analysis of the Dinoflagellate Cyst relative abundances and environmental parameters of the water column shows that sea-surface temperature, salinity, marine productivity and bottom water oxygen are the factors that relate significantly to the distribution patterns of individual species in the region. The composition of Cyst assemblages and Dinoflagellate Cyst concentrations allows the identification of four hydrographic regimes; 1) the northern regime between 17 and 14°N characterized by high productivity associated with seasonal coastal upwelling, 2) the southern regime between 12 and 6°N associated with high-nutrient waters influenced by river discharge 3) the intermediate regime between 14 and 12°N influenced mainly by seasonal coastal upwelling additionally associated with fluvial input of terrestrial nutrients and 4) the offshore regime characterized by low chlorophyll-a concentrations in upper waters and high bottom water oxygen concentrations. Our data show that Cysts of Polykrikos kofoidii , Selenopemphix quanta , Dubridinium spp., Echinidinium species, Cysts of Protoperidinium monospinum and Spiniferites pachydermus are the best proxies to reconstruct the boundary between the NE trade winds and the monsoon winds in the subtropical eastern Atlantic Ocean. The association of Bitectatodinium spongium , LejeuneCysta oliva , Quinquecuspis concreta , Selenopemphix nephroides , Trinovantedinium applanatum can be used to reconstruct past river outflow variations within this region.

  • interglacial variability mis 5 and mis 7 and Dinoflagellate Cyst assemblages in the bay of biscay north atlantic
    Marine Micropaleontology, 2008
    Co-Authors: Aurelie Penaud, Jl Turon, Fabienne Marret, Frederique Eynaud, Sebastien Zaragosi, Jeanfrancois Bourillet
    Abstract:

    The interglacial periods of the late Quaternary are frequently investigated as they constitute potential analogues for our modem climate and may shed light on the key questions of natural climate variability and future developments. The aim of this work is to reconstruct the paleoenvironmental history of Marine Isotope Stages (MIS) 5 and 7 in deep-sea sediments of the northern Bay of Biscay (North East Atlantic Ocean). On the basis of a multiproxy compilation, including analysis of Dinoflagellate Cyst assemblages, we discuss the nature of the paleoenvironmental and paleoclimate changes that took place in this region. Recurrent successions Of Species marking the beginning and the Termination of the Interglacial Complexes (MIS 5 and MIS 7) revealed a coherent scheme of water mass migration during these key transitional periods. Moreover, our data extend knowledge about the ecology of several Dinoflagellate taxa. In particular, we discuss the ecology of Spiniferites septentrionalis and note that this species can be used as a biostratigraphical tracer in North Atlantic Quaternary sediments, until a major event of iceberg calving occurred during MIS 6. dated to around 150 ka BP. The dinoCyst Spinferites mirabilis appears to be an important proxy for recognizing warm intervals within Interglacial Complexes. During MIS 5e, the Last Interglacial, this species is represented by the highest percentages ever recorded in sediments from the North Atlantic region. Peak occurrence of this species during MIS 7 indicates that substage MIS 7c, the second warm interval of the Penultimate Interglacial, represents the climatic optimum during the MIS 7 Interglacial Complex.

Stijn De Schepper - One of the best experts on this subject based on the ideXlab platform.

  • an overview and brief description of common marine organic walled Dinoflagellate Cyst taxa occurring in surface sediments of the northern hemisphere
    Marine Micropaleontology, 2019
    Co-Authors: Nicolas Van Nieuwenhove, Kenneth Neil Mertens, Vera Pospelova, Stijn De Schepper, Anne De Vernal, Martin J Head, Jens Matthiessen, Audrey Limoges, Frederique Eynaud
    Abstract:

    Abstract Organic-walled resting Cysts of planktonic Dinoflagellates occur commonly in modern marine sediment where they represent, with rare exceptions, the only geologically preservable part of the life cycle. Although many species do not produce fossilizable resting Cysts, upper Quaternary sediments contain a diverse Cyst record that is used frequently for paleoenvironmental reconstruction and stratigraphic analysis. Reconstructions of past sea-surface conditions rely on an understanding of the distributions of Dinoflagellate Cysts in modern sediments linked to their respective environmental parameters, underpinned by sound taxonomy and standardized nomenclature. Stratigraphic studies additionally require knowledge of morphological details to distinguish extant from similar extinct taxa. Here, 51 Dinoflagellate Cyst species and two informal Cyst morphotypes that are commonly encountered during routine palynological analysis of upper Quaternary marine sediments from the Northern Hemisphere are briefly described taxonomically and illustrated. In addition, their lowest stratigraphic occurrences are provided.

  • Late Neogene Dinoflagellate Cyst and acritarch biostratigraphy for Ocean Drilling Program Hole 642B, Norwegian Sea
    Review of Palaeobotany and Palynology, 2017
    Co-Authors: Stijn De Schepper, Kristina Marie Beck, Gunn Mangerud
    Abstract:

    Abstract The Arctic is a critical region in the current and past global climate system. One major challenge for investigating the geological history of the Arctic is the establishment of a rigorous chronology. To get better insights into the late Neogene history of oceanographic and climatic change in the region, well-calibrated ocean drill cores are essential. Nevertheless, detailed stratigraphy from (sub)Arctic ocean drill sites remains problematic due to the generally poor preservation of calcareous microfossils in high northern-latitude oceans. Here, organic-walled palynomorphs (Dinoflagellate Cysts and acritarchs) can compensate for the lack of calcareous microfossils because diverse and rich palynological assemblages can be recovered. We defined three magnetostratigraphically-calibrated Dinoflagellate Cyst and acritarch biozones in the Upper Miocene to Upper Pliocene of Norwegian Sea Ocean Drilling Program Hole 642B (Voring Plateau) that show potential for correlation within the Nordic Seas. It is also noted that several bioevents in the Nordic Seas are strongly diachronous with the North Atlantic, highlighting the limitations of applying North Atlantic bioevents directly to the Nordic Seas. For each of the three interval biozones (VP1 to VP3) we use the highest occurrences of acritarch and Dinoflagellate Cyst species (“ Veriplicidium franklinii ” of Anstey 1992, Reticulatosphaera actinocoronata , and InvertoCysta lacrymosa ) that are relatively synchronous across the Nordic Seas and North Atlantic and thus show potential for a North Atlantic–Arctic reference stratigraphy.

  • Complex response of Dinoflagellate Cyst distribution patterns to cooler early Oligocene oceans
    Earth-Science Reviews, 2014
    Co-Authors: Mark A. Woods, Stijn De Schepper, James B. Riding, Thijs R.a. Vandenbroucke, Mark Williams, Koen Sabbe
    Abstract:

    Previous studies have made extensive use of Dinoflagellate Cysts to reconstruct past sea surface temperature (SST). Analysis of associations of Dinoflagellate Cysts using two new ocean datasets for the mid Eocene (Bartonian) and early Oligocene (Rupelian) reveals clear latitudinally constrained distributions for the Bartonian, but unexpected changes in their Rupelian distribution; a significant number of species with low and mid latitude northern hemisphere occurrences in the Bartonian extend their northward ranges in the Rupelian, including some forms characterised as ‘warm water’ by previous studies. This suggests either that Dinoflagellates are faithfully tracking a complex oceanographic response to Rupelian cooling, or that Dinoflagellate sensitivity/adaptability to a range of ecological variables means that at a global scale their distributions are not primarily controlled by sea surface temperature-variability. Previous use of Dinoflagellate Cysts for palaeoclimate work has relied on rather subjective and inconsistent identification of ‘warm’ and ‘cold’ water forms, rather than comprehensive analysis of community associations at the global-scale. It is clear from this study that a better understanding of the (palaeo-)ecology of Dinoflagellates and their Cysts is required. Rupelian Dinoflagellate Cyst distribution may reflect changes in a range of environmental variables linked to early Oligocene climate-cooling, for example changes in nutrient fluxes triggered by glacially-induced base-level fall; complex reorganisation of ocean current systems between the Bartonian and Rupelian, or muted changes to Rupelian summer SSTs in the northern hemisphere that have previously been reported. Many extant Dinoflagellate species also exhibit relatively broad temperature tolerance. Moreover, they have potentially extensive cryptic diversity, and are able to produce dormant Cysts during short-lived environmental deterioration, all of which may act to limit the value of undifferentiated Dinoflagellate Cyst assemblages for identifying climate signals.

  • pliocene and pleistocene Dinoflagellate Cyst and acritarch zonation of dsdp hole 610a eastern north atlantic
    Palynology, 2009
    Co-Authors: Stijn De Schepper, Martin J Head
    Abstract:

    A diverse and well-preserved Dinoflagellate Cyst and acritarch record, comprising 35 genera and 104 species of Dinoflagellate Cyst and 14 acritarch taxa, is presented for the Lower Pliocene through Middle Pleistocene (4.00–0.53 Ma) of eastern North Atlantic Deep Sea Drilling Project Hole 610A. The Pliocene samples contain twice as many Dinoflagellate Cyst taxa than the Quaternary samples but far lower Cyst concentrations. The disappearance of taxa during the latest Pliocene is likely to have been associated with global cooling. Eight biozones and four subzones are established, representing a level of detail that surpasses earlier studies. The zones are based mostly on highest occurrences, as these are most prevalent in the Pliocene and Lower Pleistocene. The subzones, based on both the acme and highest persistent occurrence of HabibaCysta tectata, appear regionally useful within the Lower Pleistocene. The lowest occurrence of Impagidinium cantabrigiense is a potential marker for the uppermost Gelasian Stage (Lower Pleistocene). While this biozonation is intended primarily for use in the eastern North Atlantic, elements will be applicable across the higher-latitude North Atlantic where calcareous microfossil zonations have reduced reliability and resolution. Most of the stratigraphically useful taxa are illustrated, and selected species are described informally.

  • new Dinoflagellate Cyst and acritarch taxa from the pliocene and pleistocene of the eastern north atlantic dsdp site 610
    Journal of Systematic Palaeontology, 2008
    Co-Authors: Stijn De Schepper, Martin J Head
    Abstract:

    Synopsis A palynological study of Pliocene and Pleistocene deposits from DSDP Hole 610A in the eastern North Atlantic has revealed the presence of several new organic‐walled Dinoflagellate Cyst taxa. Impagidinium cantabrigiense sp. nov. first appeared in the latest Pliocene, within an interval characterised by a paucity of new Dinoflagellate Cyst species. Operculodinium? eirikianum var. crebrum var. nov. is mostly restricted to a narrow interval near the Mammoth Subchron within the Pliocene (Piacenzian Stage) and may be a morphological adaptation to the changing climate at that time. An unusual morphotype of Melitasphaeridium choanophorum (Deflandre & Cookson, 1955) Harland & Hill, 1979 characterised by a perforated Cyst wall is also documented. In addition, the stratigraphic utility of small acritarchs in the late Cenozoic of the northern North Atlantic region is emphasised and three stratigraphically restricted acritarchs Cymatiosphaera latisepta sp. nov., Lavradosphaera crista gen. et sp. nov. and Lavr...

Vera Pospelova - One of the best experts on this subject based on the ideXlab platform.

  • taxonomic revision phylogeny and Cyst wall composition of the Dinoflagellate Cyst genus votadinium reid dinophyceae peridiniales protoperidiniaceae
    Palynology, 2020
    Co-Authors: Pieter Gurdebeke, Kenneth Neil Mertens, Vera Pospelova, Kristin E Gribble, Kara Bogus, Haifeng Gu, Kazumi Matsuoka, Zhen Li, Henk Vrielinck
    Abstract:

    The taxonomy of the Dinoflagellate Cyst-based genus Votadinium has been in need of revision. This is accomplished here by integrating morphology, large subunit (LSU) rDNA sequences, and Cyst wall c...

  • an overview and brief description of common marine organic walled Dinoflagellate Cyst taxa occurring in surface sediments of the northern hemisphere
    Marine Micropaleontology, 2019
    Co-Authors: Nicolas Van Nieuwenhove, Kenneth Neil Mertens, Vera Pospelova, Stijn De Schepper, Anne De Vernal, Martin J Head, Jens Matthiessen, Audrey Limoges, Frederique Eynaud
    Abstract:

    Abstract Organic-walled resting Cysts of planktonic Dinoflagellates occur commonly in modern marine sediment where they represent, with rare exceptions, the only geologically preservable part of the life cycle. Although many species do not produce fossilizable resting Cysts, upper Quaternary sediments contain a diverse Cyst record that is used frequently for paleoenvironmental reconstruction and stratigraphic analysis. Reconstructions of past sea-surface conditions rely on an understanding of the distributions of Dinoflagellate Cysts in modern sediments linked to their respective environmental parameters, underpinned by sound taxonomy and standardized nomenclature. Stratigraphic studies additionally require knowledge of morphological details to distinguish extant from similar extinct taxa. Here, 51 Dinoflagellate Cyst species and two informal Cyst morphotypes that are commonly encountered during routine palynological analysis of upper Quaternary marine sediments from the Northern Hemisphere are briefly described taxonomically and illustrated. In addition, their lowest stratigraphic occurrences are provided.

  • a review of rare and less well known extant marine organic walled Dinoflagellate Cyst taxa of the orders gonyaulacales and suessiales from the northern hemisphere
    Marine Micropaleontology, 2019
    Co-Authors: Audrey Limoges, Kenneth Neil Mertens, Vera Pospelova, Martin J Head, Nicolas Van Nieuwenhove, Andre Rochon
    Abstract:

    Abstract Dinoflagellate resting Cysts with rare exception produce the only discrete link between the biology of extant Dinoflagellate species and their fossil record. The geological preservability of such Cysts allows them to be used for quantitative paleoecological reconstructions, especially in the Quaternary, and for biostratigraphy and the calibration of molecular clocks with the geological record. This contribution reviews and updates the taxonomy of 27 uncommon Dinoflagellate Cyst species and morphotypes belonging to the orders Gonyaulacales and Suessiales with occurrences in upper Quaternary marine sediments of the Northern Hemisphere. Comparative descriptions and illustrations are provided along with the biological affinity of each taxon where known and lowest stratigraphic occurrence.

  • a review of rare poorly known and morphologically problematic extant marine organic walled Dinoflagellate Cyst taxa of the orders gymnodiniales and peridiniales from the northern hemisphere
    Marine Micropaleontology, 2019
    Co-Authors: Kenneth Neil Mertens, Vera Pospelova, Pieter Gurdebeke, Yoshihito Takano, Hilal Aydin, Haifeng Gu, Dave Clarke, Zhen Li, Hyeon Ho Shin
    Abstract:

    Abstract Dinoflagellates are a major component of the modern plankton. Of the 2192 species of marine free-living Dinoflagellates presently described, an increasing number are being shown to produce resting Cysts (probably hypnozygotes) within their life cycle. With rare exception, only the resting Cysts fossilize, so they are of central importance in tracing the history of Dinoflagellates through geological time. Cysts of many of the more common Dinoflagellate species have distinctive morphologies allowing their geographic and stratigraphic occurrences to be traced. An ever-increasing number of taxa are also being shown to produce distinctive and geologically preservable Cysts, potentially enhancing our knowledge of the diverse representation of Dinoflagellates through time. Here the organic-walled Cysts of 73 rare, poorly known or morphologically problematic marine Dinoflagellate Cyst species belonging to the orders Gymnodiniales (nine species) and Peridiniales (64 species) are reviewed, described and illustrated, and their stratigraphic ranges assessed. The names Echinidinium aculeatum and Echinidinium transparantum are validated.

  • Dinoflagellate Cyst production in the cariaco basin a 12 5 year long sediment trap study
    Progress in Oceanography, 2019
    Co-Authors: Vera Pospelova, Manuel Bringue, Eric Tappa, Robert C Thunell
    Abstract:

    Abstract Seasonal and interannual variability in Dinoflagellate Cyst production were assessed using a 12.5 year-long sediment trap time series from the Cariaco Basin (southern Caribbean Sea). This study constitutes the longest such time series published to date, providing robust patterns of variability for individual Dinoflagellate Cyst taxa as well as for major phytoplanktonic and (micro-)zooplanktonic groups at the site. Cyst production is interpreted in the context of physico-chemical properties measured in situ at the mooring site (primarily reflecting seasonal upwelling), and considering potential interactions with other major components of the pelagic food web (e.g., diatoms, ciliates, copepods). The time series consists in >300 sediment trap samples, each representing ∼14 days of sedimentation, collected at the CARIACO station between Nov. 8, 1996 and May 19, 2009. Mass fluxes of biogenic silica, calcium carbonate and organic carbon reflect dominantly the timing and strength of wind-driven, seasonal upwelling that brings colder, nutrient-rich waters to the surface, fostering primary productivity and the export of biogenous materials to the depths. On seasonal time scales, Dinoflagellate Cyst production is closely coupled with upwelling strength, with higher Cyst fluxes consistently observed under active upwelling conditions (average of 50.5 × 103 Cysts m−2 day−1) compared to non-active upwelling intervals (29.0 × 103 Cysts m−2 day−1). Year-to-year variability is characterized by a large increase in Cyst production observed over the last ∼4 years of the time series (2006–2009) and minimum Cyst fluxes recorded in the years 1998 and 1999, following the strong 1997/98 El Nino event. Dinoflagellate Cyst assemblages are dominated by Brigantedinium spp. (59.1%), accompanied by Echinidinium delicatum (10.8%), Bitectatodinium spongium (8.4%), Spiny brown type A (2.9%) and Echinidinium spp. (2.4%). Cyst produced by both autotrophic and heterotrophic Dinoflagellates generally respond positively to upwelling in the basin. Most Cyst taxa are associated with active upwelling conditions (e.g., Bitectatodinium spongium, Brigantedinium spp., Echinidinium delicatum, Quinquecuspis concreta, Selenopemphix quanta, Spiny brown type C), with some showing higher fluxes under active but weak upwelling conditions (e.g., Echinidinium granulatum, Echinidinium spp., Cyst of P. fukuyoi, Spiny brown type A). Other Cyst taxa tend to show higher abundances at the onset of upwelling conditions (e.g., Echinidinium aculeatum, Cyst of Protoperidinium stellatum) or following active upwelling intervals (e.g., LejeuneCysta marieae, Selenopemphix nephroides). The detailed response of each Dinoflagellate Cyst taxon to environmental variability is presented in the form of an atlas, providing photomicrographs and detailing overall monthly production, contribution to the total trap assemblage as well as Cyst production over the 12.5 years of the time series.

Han Leereveld - One of the best experts on this subject based on the ideXlab platform.

  • Hauterivian-Barremian (Lower Cretaceous) Dinoflagellate Cyst stratigraphy of the western Mediterranean
    Cretaceous Research, 1997
    Co-Authors: Han Leereveld
    Abstract:

    Abstract This paper focuses on the qualitative Dinoflagellate Cyst distribution in the Hauterivian-Barremian rocks of the western Mediterranean. Results are presented of research on the ammonite controlled pelagic Rio Argos succession near Caravaca (southeast Spain) which are integrated with information on calibrated sections in southeast France and Switzerland. The ammonite framework permitted determination of contemporaneous first and last occurrences of Dinoflagellate Cyst taxa in the three areas. Mainly based on these biostratigraphic events, six successive Dinoflagellate Cyst zones are defined and identified in the Hauterivian-Barremian of the Rio Argos succession and the type section of the Barremian at Angles (southeast France). The established zonation, which is by definition valid for the whole western Mediterranean region, has the potential for world-wide application. In addition, a high-resolution zonation, described as a suite of subzones, is established based on six successive shifts in the Hauterivian Dinoflagellate Cyst development in the Rio Argos succession. These local palaeoecological changes are considered to reflect palaeoenvironmental and/or climatic changes of a regional, interregional or global nature.

  • Upper Tithonian-Valanginian (Upper Jurassic-Lower Cretaceous) Dinoflagellate Cyst stratigraphy of the western Mediterranean☆
    Cretaceous Research, 1997
    Co-Authors: Han Leereveld
    Abstract:

    Abstract This study focuses on the qualitative Dinoflagellate Cyst distribution in the Upper Tithonian-Valanginian rocks of the western Mediterranean. Results are presented of research on the ammonite controlled pelagic Rio Argos succession near Caravaca (SE Spain) which are integrated with information from calibrated sections in southeast France and Switzerland. The ammonite framework permitted determination of contemporaneous first and last occurrences of Dinoflagellate Cyst taxa in the three areas. Mainly based on these biostratigraphic events, four successive Dinoflagellate Cyst zones are defined and identified in the Upper Tithonian-Valanginian succession of the western Mediterranean. The established zonation has potential for world-wide application. In addition, a high-resolution zonation, described as a suite of subzones, is established based on seven successive shifts in the Dinoflagellate Cyst development of the Upper Berriasian-Valanginian in the Rio Argos succession exclusively. These local palaeoecological changes are considered to reflect palaeoenvironmental and/or climatic changes of a regional, interregional or global nature.