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| Registros recuperados: 31 | |
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| Nezan, Elisabeth; Bilien, Gwenael; Boulben, Sylviane; Mertens, Kenneth; Chomerat, Nicolas. |
| A new marine raphid diatom, Plagiolemma distortum Nézan, sp. nov. is described from plankton samples from the Atlantic Ocean, south Brittany (north-western France), where it was regularly observed, but never in high abundances. Cells have an unusual and complex shape under light microscopy (LM) depending on their position and orientation. The two valves are highly vaulted and narrow in width (transapical axis). Cells contain four complexly lobed plastids and a variable number of refractive granules without particular localization. In addition, capsules containing motile cells were observed. Ultrastructural details of the frustules were investigated using scanning electron microscopy (SEM). The girdle bands are simple. Each valve possesses a sigmoid raphe... |
| Tipo: Text |
Palavras-chave: Capsules; Habitat; Molecular phylogeny; Plastids; Raphid diatom; Video. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00441/55235/56797.pdf |
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| Chapelle, Annie; Le Gac, Mickael; Labry, Claire; Siano, Raffaele; Quere, Julien; Caradec, Florian; Le Bec, Claude; Nezan, Elisabeth; Doner, Anne; Gouriou, Jeremie. |
| Tipo: Text |
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| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00278/38921/37461.pdf |
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| Tillmann, Urban; Gottschling, Marc; Nezan, Elisabeth; Krock, Bernd; Bilien, Gwenael. |
| Some species of the planktonic dinoflagellate genus Azadinium produce azaspiracids (AZAs), a group of lipophilic phycotoxins causing human poisoning after mussel consumption. We describe three new species from the North Atlantic, all of which shared the same Kofoidean plate pattern characteristic for Azadinium: Po, cp, X, 4′, 3a, 6′́, 6 C, 5S, 6′́́, 2′́́́. Azadinium trinitatum sp. nov. was mainly characterized by the presence of an antapical spine and by the position of the ventral pore at the left distal end of the pore plate in a cavity of Plate 1′ Plate 1. Azadinium cuneatum sp. nov. had a conspicuously formed first apical plate, which was asymmetrically elongated and tapered on its left lateral side with a ventral pore located at the tip of this... |
| Tipo: Text |
Palavras-chave: Azadinium; Azaspiracids; Irminger Sea; Iceland; New species. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00188/29917/28382.pdf |
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| Luo, Zhaohe; Mertens, Kenneth; Nezan, Elisabeth; Gu, Li; Pospelova, Vera; Thoha, Hikmah; Gu, Haifeng. |
| The dinoflagellate order Peridiniales encompasses several well circumscribed families. However, the family level of some genera, such as Bysmatrum and Vulcanodinium, has remained elusive for many years. Four Peridinium-like strains were established from the Atlantic coast of France and North Sulawesi, Indonesia through cyst germination or isolation of single cells. The cyst-theca relationship was established on specimens from the French Atlantic. Their morphologies were examined using light, scanning and transmission electron microscopy. The cells were characterized by a much larger epitheca relative to the hypotheca, a large anterior sulcal (Sa) plate deeply intruding the epitheca and a small first anterior intercalary plate. The plate formula was... |
| Tipo: Text |
Palavras-chave: Bysmatrum; Cyst; Dinoflagellate; Eyespot; Peridiniales; Plate overlap. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00489/60112/63564.pdf |
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| Le Gal, Dominique; Nezan, Elisabeth; Raguenes, Pierre; Piclet, Guy. |
| Dans le cadre du Réseau de surveillance phytoplanctonique, nous nous sommes intéressés à un phénomène particulier d'eaux colorées. L'espèce responsable Chaetoceros armatum a fait l'objet d'un suivi sur plusieurs mois et les résultats exposés dans ce rapport concernent essentiellement la période février 1992 à mars 1993. Nous nous limiterons à présenter cette espèce particulière pour laquelle la bibliographie est assez pauvre, et à décrire le phénomène in situ. |
| Tipo: Text |
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| Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/00017/12806/9749.pdf |
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| Mertens, Kenneth; Carbonell-moore, Maria Consuelo; Pospeloya, Vera; Head, Martin J.; Highfield, Andrea; Schroeder, Declan; Gu, Haifeng; Andree, Karl B.; Fernandez, Margarita; Yamaguchi, Aika; Takano, Yoshihito; Matsuoka, Kazumi; Nezan, Elisabeth; Bilien, Gwenael; Okolodkov, Yuri; Koike, Kazuhiko; Hoppenrath, Mona; Pfaff, Maya; Pitcher, Grant; Al-muftah, Abdulrahman; Rochon, Andre; Lim, Po Teen; Leaw, Chui Pin; Lim, Zhen Fei; Ellegaard, Marianne. |
| trains of a dinoflagellate from the Salton Sea, previously identified as Protoceratium reticulatum and yessotoxin producing, have been reexamined morphologically and genetically and Pentaplacodinium saltonense n. gen. et sp. is erected to accommodate this species. Pentaplacodinium saltonense differs from Protoceratium reticulatum (Claparède et Lachmann 1859) Bütschli 1885 in the number of precingular plates (five vs. six), cingular displacement (two widths vs. one), and distinct cyst morphology. Incubation experiments (excystment and encystment) show that the resting cyst of Pentaplacodinium saltonense is morphologically most similar to the cyst-defined species Operculodinium israelianum (Rossignol, 1962) Wall (1967) and O. psilatum Wall (1967).... |
| Tipo: Text |
Palavras-chave: Pentaplacodinium; Protoceratium; Precingular plates; Salton Sea; Ceratocorys; Operculodinium; Cribroperidinioideae. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00416/52756/53852.pdf |
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| Zendong, Suzie Zita; Kadiri, Medina; Herrenknecht, Christine; Nezan, Elisabeth; Mazzeo, Antonia; Hess, Philipp. |
| Algal toxins may accumulate in fish and shellfish and thus cause poisoning in consumers of seafood. Such toxins and the algae producing them are regularly surveyed in many countries, including Europe, North America, Japan and others. However, very little is known regards the occurrence of such algae and their toxins in most African countries. This paper reports on a survey of phytoplankton and algal toxins in Nigerian coastal waters. Seawater samples were obtained from four sites for phytoplankton identification, on three occasions between the middle of October 2014 and the end of February 2015 (Bar Beach and Lekki in Lagos State, Port Harcourt in Rivers State and Uyo in Akwa Ibom State). The phytoplankton community was generally dominated by diatoms and... |
| Tipo: Text |
Palavras-chave: Dinoflagellates; Dinophysis; Phycotoxins; Untargeted analysis; Phytoplankton. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00314/42521/41893.pdf |
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| Gohin, Francis; Lampert, Luis; Guillaud, Jean-francois; Herbland, Alain; Nezan, Elisabeth. |
| A phytoplankton bloom was observed in late winter 2000, on the continental shelf offshore of southern Brittany, in northwestern Bay of Biscay. This bloom appeared initially along the 120-m isobath, in stratified and clear waters, at the interface between the oceanic water and the plumes of southern Brittany rivers (mainly the Loire and Vilaine). The development of the bloom was triggered by favourable meteorological conditions, characterised by solar irradiance reaching the maximum level expected for that period of the year. Outside of the bloom area, the phytoplankton photosynthesis was irradiance limited: inshore, because of the stronger attenuation of the light; offshore, because of the weak stratification. The hydrological conditions at the onset of... |
| Tipo: Text |
Palavras-chave: Bay of Biscay; Coscinodiscus; Algal bloom; Phytoplankton; Ocean colour; Satellite sensing. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/publication-463.pdf |
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| Amzil, Zouher; Sibat, Manoella; Chomerat, Nicolas; Grossel, Hubert; Marco-miralles, Francoise; Lemee, Rodolphe; Nezan, Elisabeth; Sechet, Veronique. |
| Dinoflagellates of the genus Ostreopsis are known to cause (often fatal) food poisoning in tropical coastal areas following the accumulation of palytoxin (PLTX) and/or its analogues (PLTX group) in crabs, sea urchins or fish. Ostreopsis spp. occurrence is presently increasing in the northern to north western Mediterranean Sea (Italy, Spain, Greece and France), probably in response to climate change. In France, Ostreopsis. cf. ovata has been associated with toxic events during summer 2006, at Morgiret, off the coast of Marseille, and a specific monitoring has been designed and implemented since 2007. Results from 2008 and 2009 showed that there is a real danger of human poisoning, as these demonstrated bioaccumulation of the PLTX group (PLTX and ovatoxin-a)... |
| Tipo: Text |
Palavras-chave: Ostreopsis cf. ovata; Palytoxin; Ovatoxin-a; LC-MS/MS; Seafood. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00071/18230/15799.pdf |
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| Kempf, Marc; Jacq, E; Le Guellec, C; Merceron, Michel; Monfort, Patrick; Nezan, Elisabeth; Ryckaert, Mireille. |
| This document presents a year-long (1994) environmental study conducted on a site of intensive farming of salmonids (mainly fario trout) in Camaret Bay. A set of parameters were considered for the body of water and the sea bed (flow patterns, hydrology, sedimentology, biology, chemistry) and complemented by video observations. The study concluded that there was a measurable effect from the farm in its current configuration, but that the impact was of a very limited intensity and scope that did not affect the environment in a substantial way. It is recommended that production growth be accompanied by a minimum amount of environmental assessment. |
| Tipo: Text |
Palavras-chave: Bretagne; Truite fario; Salmonidés; Environnement; Pisciculture marine. |
| Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/1995/rapport-2834.pdf |
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| Kempf, Marc; Merceron, Michel; Nezan, Elisabeth. |
| Brown water was observed in Camaret Cove, on 27 and 28 September 1994, because of the massive proliferation of a toxic phytoplankton alga. The densities reached by this alga were considerable: from 1.5 million cells per litre at a point far from the coast to 130 million cells per litre at the height of the efflorescence at the bottom of the bay, in the port's waters. The toxicity of this alga caused deaths in the farms of salmonids in cages set up at this site. The SEMII (IFREMERINRA research facility) experimental farm recorded 100% losses (15-20% on 27 September and the entire remaining stock during the night of 27-28 September), which is around 10 tonnes of fario trout and 0.5 tonne of Atlantic salmon. Aside from the economic loss, this represents a... |
| Tipo: Text |
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| Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/1995/publication-2831.pdf |
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| Lemonnier, Hugues; Lantoine, Francois; Courties, Claude; Guillebault, Delphine; Nezan, Elisabeth; Chomerat, Nicolas; Escoubeyrou, Karine; Galinie, Christian; Blockmans, Bernard; Laugier, Thierry. |
| Tropical shrimp aquaculture systems in New Caledonia regularly face major crises resulting from outbreaks of Vibrio infections. Ponds are highly dynamic and challenging environments and display a wide range of trophic conditions. In farms affected by vibriosis, phytoplankton biomass and composition are highly variable. These conditions may promote the development of harmful algae increasing shrimp susceptibility to bacterial infections. Phytoplankton compartment before and during mortality outbreaks was monitored at a shrimp farm that has been regularly and highly impacted by these diseases. Combining information from flow cytometry, microscopy, pigment and phylogenetic analysis, the presence of Picocyanobacteria, Prasinophyceae and Diatomophyceae were... |
| Tipo: Text |
Palavras-chave: Tropical aquaculture pond; Litopenaeus stylirostris; Vibriosis; Eutrophication; Phytoplankton; Harmful algae. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00343/45411/44986.pdf |
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| Lema, Anais Kimberley; Latimier, Marie; Nezan, Elisabeth; Fauchot, Juliette; Le Gac, Mickael. |
| The factors responsible for inducing the synthesis of toxins and responses from toxic phytoplankton blooms remain unclear. In this study we compare the influence of genotypic (at both the intra and interspecific levels) and environmental factors (nutrient concentration and ratio) on growth (in terms of cell densities) and domoic acid (DA) production in three Pseudo-nitzschia species: P. australis, P.pungens and P.fradulenta. A strong phosphate effect was detected. More precisely, a low initial concentration in phosphate, even at high initial nitrogen and silicate concentrations, induced the highest DA concentrations and the lowest cell densities in all strains/species studied. In contrast, a low initial concentration of nitrogen and silicate combined, with... |
| Tipo: Text |
Palavras-chave: Pseudo-nitzschia strains; Domoic acid; Ratio; Phosphate; Nitrogen. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00377/48849/49397.pdf |
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| Lassus, Patrick; Chomerat, Nicolas; Hess, Philipp; Nezan, Elisabeth. |
| This book updates available international databases on toxic and harmful species of phytoplankton and micro-phytobenthos. It lists regional occurrences at world-wide scale: localities, cell densities, toxicity levels in contaminated animals, human and animal poisoning, isolation of identified active molecules and toxins, documentary sources. Finally, this book addresses the geographic distributions of phycotoxin-producers from recent data. The objective is to analyze the evolution of toxic and harmful episodes over the past 30 years to identify trends, and to introduce a discussion on the reality of a time-dependent increase in the number of known species and toxins. |
| Tipo: Text |
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| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00379/49054/49508.pdf |
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| Mertens, Kenneth; Chomerat, Nicolas; Nezan, Elisabeth; Bruneau, Audrey; Le Bec, Claude. |
| Les inspections vétérinaires de la Commission Européenne ayant signifié à la France son constat d'une absence de réserau de surveillance sur les claires ostréicoles, la DGAL a mandaté l'Ifremer afin de réaliser un premier diagnostic sur le phytoplancton. Cette commande de la DGAL place l'Ifremer LERBO comme prestataire de service et spécialiste des micro-algues. Les claires ostréicoles étant hors du domaine public maritime, une concertation avec le Comité Régional de la Conchyliculture de Poitou-Charentes, la DGAL et la DDTM 17 en juin 2018 a permis de proposer six claires, réparties entre l'île de Ré et l'île d'Oléron et pouvant être échantillonnées. L'objectif est de faire un état des lieux de la présence ou de l'absence de cellules de phytoplancton... |
| Tipo: Text |
Palavras-chave: Charentes; Claire; Phytoplancton; Micro-algue; Toxine. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00486/59731/62828.pdf |
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| Registros recuperados: 31 | |
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