Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
The brown algal genus Padina (Dictyotales, Phaeophyceae) is distributed worldwide in tropical and temperate seas. Global species diversity and distribution ranges, however, remain largely unknown. Species-level diversity was reassessed using DNA-based, algorithmic species delineation techniques based on cox3 and rbcL sequence data from 221 specimens collected worldwide. This resulted in estimates ranging from 39 to 61 putative species (ESUs), depending on the technique as well as the locus. We discuss the merits, potential pitfalls, and evolutionary and biogeographic significance of algorithmic species delineation. We unveil patterns whereby ESUs are in all but one case restricted to either the Atlantic or Indo-Pacific Ocean. Within ocean basins we find evidence for the vast majority of ESUs to be confined to a single marine realm. Exceptions, whereby ESUs span up to three realms, are located in the Indo-Pacific Ocean. Patterns of range-restricted species likely arise by repeated founder events and subsequent peripatric speciation, hypothesized to dominate speciation mechanisms for coastal marine organisms in the Indo-Pacific. Using a three-gene (cox3, psaA and rbcL), relaxed molecular clock phylogenetic analysis we estimated divergence times, providing a historical framework to interpret biogeographic patterns.
ISSN: 0022-3646

hal-01545323
https://hal.archives-ouvertes.fr/hal-01545323
DOI : 10.1111/jpy.12027

Éditeur(s) : Station Biologique de Roscoff
Résumé : The first record of interstitial polychaetous annelids dates no more than forty years. Presently, the total number of interstitial species described is about one hundred. Up to the present, the large group of Aphroditoidea includes no interstitial representative. A few samples made by Pr Swedmark and M. Lasserre in Bermudas enable the discovery of an undescribed species of an interstitial Sigalionidae, Pholoe swedmarki Sp. n., together with two other interstitial species of Pisionidae and Syllidae, new to the western tropical atlantic. From a morphological point of view, the comparison of P. swedmarki sp. n. with the other species of the genus reveals some adaptations to the interstitial life: reduction of the body size, reduction or, at the contrary, enlargement of some appendages of the anterior part, lack of pigmentation. From the biological point of view, P. swedmarki sp. n. displays a remarkable group of characteristics : extreme reduction of the eggs numbers, extension of the reproductive period, pregnancy of the embryos and juveniles up to a very late ontogenetical stage. The hypothesis of an intra-elytral pregnancy, involving an internal fertilization, is discussed. By its morphology and biology, P. swedmarki sp. n. forms the first undeniable example of adaptation to the interstitial life among the Aphroditoidea. [NOT CONTROLLED OCR]
La découverte des premières Annélides Polychètes interstitielles remonte à peine à une quarantaine d'années. A l'heure actuelle, le nombre total d'espèces interstitielles décrites est de l'ordre d'une centaine. Jusqu'à présent, le vaste groupe des Aphroditoidea ne comprenait aucun représentant interstitiel. Quelques récoltes effectuées aux Bermudes par le Pr Swedmark et M. Lasserre ont permis de découvrir une espèce inédite de Sigalionidae interstitiel, Pholoe swedmarki sp. n., en compagnie de deux autres espèces de Pisionidae et de Syllidae interstitielles encore inconnues dans l'Atlantique tropical Ouest. Sur le plan morphologique, la comparaison de P. swedmarki sp. n. avec les autres espèces du genre met en évidence un certain nombre d'adaptations à la vie interstitielle : réduction de la taille du corps, réduction ou, au contraire, développement de certains appendices de la région antérieure, absence de pigmentation. Du point de vue biologique, P. swedmarki sp. n. présente un ensemble d'adaptations remarquables : réduction extrême du nombre d'oeufs, allongement de la période de reproduction, gestation des embryons et des jeunes vers jusqu'à un stade ontogénétique très avancé. L'hypothèse d'une gestation intra-élytrale, impliquant une fécondation interne, est avancée. Par sa morphologie et sa biologie, P. swedmarki sp. n. constitue le premier exemple incontestable d'adaptation à la vie interstitielle chez un Aphroditoidea. [OCR NON CONTRÔLE]
Cahiers de Biologie Marine (Station Biologique de Roscoff), 1974 , Vol. 16 , N. 5 , P. 671-683

Droits : Station Biologique de Roscoff
http://archimer.ifremer.fr/doc/1974/publication-5462.pdf
http://archimer.ifremer.fr/doc/00000/5462/

Éditeur(s) : Pergamon-elsevier Science Ltd
Résumé : Catch data of large pelagic fish such as tuna, swordfish and billfish are highly variable ranging from short to long term. Based on fisheries data, these time series are noisy and reflect mixed information on exploitation (targeting, strategy, fishing power), population dynamics (recruitment, growth, mortality, migration, etc.), and environmental forcing (local conditions or dominant climate patterns). In this work, we investigated patterns of variation of large pelagic fish (i.e. yellowfin tuna, bigeye tuna, swordfish and blue marlin) in Japanese longliners catch data from 1960 to 2004. We performed wavelet analyses on the yearly time series of each fish species in each biogeographic province of the tropical Indian and Atlantic Oceans. In addition, we carried out cross-wavelet analyses between these biological time series and a large-scale climatic index, i.e. the Southern Oscillation Index (Sol). Results showed that the biogeographic province was the most important factor structuring the patterns of variability of Japanese catch time series. Relationships between the SOI and the fish catches in the Indian and Atlantic Oceans also pointed out the role of climatic variability for structuring patterns of variation of catch time series. This work finally confirmed that Japanese longline CPUE data poorly reflect the underlying population dynamics of tunas. (C) 2010 Elsevier Ltd. All rights reserved.
Progress In Oceanography (0079-6611) (Pergamon-elsevier Science Ltd), 2010-07 , Vol. 86 , N. 1-2 , P. 276-282

Droits : 2010 Elsevier B.V. All rights reserved.
http://archimer.ifremer.fr/doc/00011/12231/9029.pdf
DOI:10.1016/j.pocean.2010.04.019
http://archimer.ifremer.fr/doc/00011/12231/

Résumé : Bacteriological study of abyssal sediments: During the Demeraby mission of the N/O Jean Charcot in the western Atlantic Ocean, a study of the microflora of the digestive tracts of echinoderms (Holothuroidea of various genera, Asteroidea, Echinoidea) was compared with that of the surrounding sediment. The bacterial concentration observed in the digestive tracts of all the animals studied is higher than that in the surrounding sediments. The largest numbers were always found in the most anterior part of the digestive tracts of the holothurians. In some cases, the increase is considerable (7.10 versus 5.2. 10 cells per millilitre): It indicates a proliferation of bacterial cells in the anterior part of the digestive tract. As the sediment moves through the digestive tract, the bacterial level progressively decreases. In the most posterior part, the concentration is, however, always clearly greater than that in the surrounding sediment. In the case of the holothurian of the genus Deima, analysis according to the Adamsonian principle of comparison shows that the microflora isolated from the various parts of the digestive tract is composed of taxonomic groups showing little resemblance to those isolated from the sediment. In the case of the holothurian of the genus Pseudostichopus, no specialisation of the microflora from digestive tract contents appears with respect to that of the ingested sediment. Examination of metabolic activities suggests a juxtaposition of two types of communities: Free sediment - sediment in transit that complement one other in their enzymatic and nutritional behaviour Indeed, the strains of free sediment seem to be rather suitable for hydrolysing and using carbohydrates, while those of enteric communities prefer the hydrolysis of lipids and proteins and the assimilation of fatty acids, dicarboxylic acids, hydroxylic acids and certain amino acids. Moreover, the enteric microflorae possess a greater nutritional versatility that, linked with its total numbers, has a sizeable catabolic potential. .../... -2- Measurements of heterotrophic activity done by means of 14 C glucose tracers make it possible to show that the metabolic activities of the bacterial communities of superficial abyssal sediments vary according to zones. In the Amazon Cone, a clear glucose mineralization gradient over a distance of a few kilometres can be observed. In the abyssal plain of Demerara heterotrophic activities are slowed in relation to those of the superficial sediments of the Cone of the Amazon, even though the bacterial numbers and the depths are of the same order of magnitude in the two zones. The abundant microflorae associated with the various divisions of digestive tract contents of the Deima abyssal holothurian manifest little metabolic activity as regards the glucose. However, the bacterial communities of Pseudostichopus and Psychropotes manifest very strong heterotrophic activities, increasing from the oesophagus towards the cloaca. Current results are too fragmentary to allow us to observe possible physiological specialisation of enteric bacterial communities enabling the facilitation of digestion processes in the host. Conclusion: In the abyssal environment, characterised by poorly developed bacterial communities, microflorae associated with the digestive tract contents of echinoderms have considerably greater cellular concentrations. By means of their enzymatic equipment, these enteric communities, which complement those of the free microflorae of superficial sediments, can participate in the transformation of organic matter in the abyssal area. Study of the dynamics of microbial communities and their heterotrophic activities in shellfish farms: From experiments done on the water in the Arcachon basin, trials to quantify and describe the reactivity potential of bacterial communities were performed. Bacterial communities were defined by direct counts, counts after setting them up for cultivation, structure and diversity of these communities, dosage of AMP, ADP, ATP. Two opposite ecological conditions were considered: Autumn conditions (high temperature) and a winter conditions (low temperature). Tubs of sea water of 6 and 60 litres were enriched either with ammonium chloride or a mixture of amino acids, at about 500 uAtg N.L. The experiments lasted 24 hours, with sampling every 3 hours. The autumn community reacted rapidly (6 hours), the response to the enrichment in organic nitrogen being the highest. The structure of the community has unstable immature stages. On the contrary, during the winter experiment, no response could be perceived. This may mean that the latency phase is greater than 24 hours. The structure of this community has mature stages. In conclusion, bacterial communities react in the same way as macroscopic communities. Stable communities are diversified and correspond to mature stages of the ecosystem; the immature stages are unstable and less diversified. This type of experiment has made it possible to bring to light the rapidity of response of bacterial populations, and can be used to define the stability of a bacterial community in a precise biotope.
ETUDE BACTERIOLOGIQUE DES SEDIMENTS ABYSSAUX RESUME Au cours de la mission DEMERABY du n/o Jean CHARCOT en atlantique occidental , une étude de la microflore des tractus digestifs d'Echinodermes (Holothurides de différents genres, Astérides, Echinides) a été comparée à celle du sédiment environnant. La concentration bactérienne observée dans les tractus digestifs de tous les animaux étudiés est supérieure à celle des sédiments environnants. Les effectifs les plus importants sont toujours observés dans la partie la plus antérieure des tractus digestifs des holothuries. Dans certains cas, l'accroissement est considérable (7.10 contre 5,2. 10 cellules/ml) : il indique une prolifération des cellules bactériennes dans la partie antérieure du tractus digestif. Au.cours de la progression du sédiment dans le tractus digestif, la charge bactérienne décroit progressivement. Dans la partie la plus postérieure, la concentration est cependant toujours nettement supérieure à celle du sédiment environnant-. Dans le cas d'une holothurie du genre Deima, l'analyse selon le principe adansonien de comparaison montre que la microflore isolée des différentes parties du tractus digestif est constituée de groupes taxonomiques présentant peu de ressemblance avec ceux isolés du sédiment. Dans le cas d'une holothurie du genre Pseudostichopus il n'apparait pas de spécialisation de la microflore du contenu du tractus digestif par rapport à celle du sédiment ingéré. ¿ ¿ . L'étude des activités métaboliques suggère une juxtaposition de deux types de communautés : sédiment libre-sédiment en transit qui se complètent dans leur comportement enzymatique et nutritionnel. En effet les souches du sédiment libre semblent être plutôt aptes à hydrolyser et à utiliser les glucides, tandis que celles des communautés entériques portent leur préférence sur l'hydrolyse des lipides et protéines et 1'assimilation des acides gras, acides dicarboxyl iques, hydro'xy-acides et certains acides aminés. D'autre part les microflores entériques possèdent une versatilité nutritionnelle plus importante qui, liée à leurs effectifs, offre une potentialité catabolique non négligeable. .../... -2- Les mesures d'activité hétérotrophe effectuées au moyen de traceurs glucose 14 C permettent de montrer que les activités métaboliques des communautés bactériennes des sédiments abyssaux superficiels varient selon les zones. Dans le Cone de l'Amazone on observe un net gradient de minéralisation du glucose sur une distance de quelques kilomètres. Dans la plaine abyssale de Demerara les activités hétérotrophessont ralenties par rapport à celles des sédiments superficiels du Cone de l'Amazone, bien que les effectifs bactériens et les profondeurs soient du même ordre de grandeur dans ces deux zones. Les abondantes microflores associées aux différentes fractions du contenu du tractus digestif de l'holothurie abyssale Deima ne manifestent que peu d'activités métaboliques vis à vis du glucose. Par contre les communautés . bactériennes de Pseudostichopus et P syahropotes manifestent des activités hétérotrophes très fortes, croissant de 1'oesophage vers le cloaque. Les résultats actuels sont trop fragmentaires pour permettre d'observer une éventuelle spécialisation physiologique des communautés bactériennes entëriques permettant de faciliter les processus de digestion chez l'hôte. Conclusion: dans le milieu abyssal, caractérisé par des communautés bactériennes faiblement développées, les microflores associées aux contenus de tractus digestif des Echinodermes présentent des concentrations cellulaires considérablement plus importantes. Par leurs équipements enzymâtiques ces communautés entëriques complémentaires de ceux des microflores libres des sédiments superficiels, peuvent participer à la transformation des matières organiques du domaine abyssal. ETUDE DE LA DYNAMIQUE DES COMMUNAUTES MICROBIENNES ET DE LEURS ACTIVITES HETEROTROPHES DANS LES PARCS CONCHYLICOLES RESUME A partir d'expérimentations effectuées sur l'eau du bassin d'Arcachon, des essais de quantification et qualification du potentiel de réactivité des communautés bactériennes ont été effectuées. Les communautés bactériennes ont été définies par comptage directs, comptages après mise en culture, structure et diversité de ces communautés, dosage des AMP, ADP, ATP. Deux situations écologiques opposées ont étées considérées . Une situation automnale (température élevée) et une situation hivernale (température faible). Des bacs d'eau de mer de 6 et 60 litres ont été enrichis , soit avec du chlorure d'ammonium, soit avec un mélange d'acides aminés, à environ 500 uAtg N.l" . Les expériences ont duré 24 heures, avec des prélèvements toutes les 3 heures. La communauté automnale réagit rapidement (6 heures), la ' réponse à l'enrichissement en azote organique étant la plus importante. La structure de la communauté présente des stades immatures instables. Au contraire, au cours de l'expérimentation hivernale, aucune réponse n'a pu être perçue. Ceci peut signifier que la phase de latence est supérieure à 24 heures. La structure . de cette communauté présente des stades matures. En Conclusion, les communautés bactériennes réagissent de la même façon que les communautés macroscopiques. Les communautés stables sont diversifiées et correspondent à des stades matures de l'écosystème, les stades immatures sont instables et moins diversifiés. Ce type d'expérience a permi de mettre en évidence la rapidité de réponse des populations bactériennes, et peut être utilisé pour définir la stabilité d'une communauté bactérienne dans un biotope précis.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1981/rapport-1926.pdf
http://archimer.ifremer.fr/doc/00000/1926/

Éditeur(s) : Office Int Epizooties
Résumé : The tremendous development of penaeid shrimp culture across the world over the past twenty years has led to international trade in eggs, larvae and spawners of the best shrimp species for aquaculture. Trade has involved, in particular, the following species: - Penaeus japonicus from Japan to Europe, the Pacific Islands and South America - P. monodon from South-East Asia to almost all tropical countries - P. vannamei and P. stylirostris from countries along the Pacific coast of South and Central America to the United States of America, the islands of the South Pacific, countries along the Atlantic coast of the Americas and certain countries in Africa. In the 1980s, research conducted by American and French teams enabled the breeding of stocks of spawners in captivity. This resulted in the establishment of lines of captive broodstock outside natural areas of distribution, and the development of new breeding farms in previously unproductive regions. Trade related to movements of these species is facilitated by the absence of legislation in most countries; even when such legislation does exist, it is not always applied These practices have led to the rapid development of world shrimp production, but have also contributed to the dissemination of pathogens. In recent years, the occurrence of serious epizootics - occasioning heavy losses world-wide - has led to a more cautious approach involving trade of post-larvae obtained from captive broodstock in which thorough control measures have been implemented for known diseases. Trade in wild shrimp will probably be abandoned progressively, to avoid the risk of introducing new pathogens. The main challenges for research in the near future are the development of diagnostic tools, to enable continuous control of captive broodstock, and the selection of strains which are resistant to the principal pathogens affecting these species.
Revue Scientifique Et Technique-office International Des Epizooties (0253-1933) (Office Int Epizooties), 1996-06 , Vol. 15 , N. 2 , P. 499-515

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00091/20231/17883.pdf
http://archimer.ifremer.fr/doc/00091/20231/

Éditeur(s) : Actes de colloques Ifremer, Tahiti, French Polynesia, 20 Feb - 4 Mar 1989, n°9, chap. 44, pp.485
Résumé : Centropomidae and Serranidae, sometimes collectively misnamed "sea basses", are suitable for aquaculture in pens, ponds, and raceways around the tropical and subtropical latitudes of the world. Western Atlantic Ocean species were recently considered for farming. South Florida, Mexico, Central and South America and the Antilles areas of the Caribbean Basin have extensive areas suitable for farming groupers and snook. Principal species of interest are the common snook (Centropomus undecimalis ), the fat snook (C. parallelus ), the Nassau grouper (Epinephelus striatus ), Black seabass (Centropristis striatus ), Gag (Mycteroperca microlepis ), and jewfish (E. itajara ).

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1989/acte-1477.pdf
http://archimer.ifremer.fr/doc/00000/1477/

Éditeur(s) : Université de Bretagne Occidentale
Résumé : Several small pelagic fish species contribute remarkably to world catch. Their populations are, however, characterized by large biomass fluctuations strongly affecting fisheries. The fishing gears and methods used to capture small pelagics have evolved to exploit the highly developed shoaling behavior of these species. Hence, faced to modern fishing this gregarious behavior becomes a disadvantage for fish. Fish behavior may be affected by environmental conditions and by fishing, at the same time that behavior impacts fishing. In this study, we seek to characterize the aggregative systems of small pelagic fishes inhabiting the Bay of Biscay by analyzing "acoustic images", defined as the group of echoes (planktonic layers, shoals, isolated targets) detected on a transect section of a given length. We analyzed the species composition, the spatial distribution and the evolution over time of acoustic images. We also studied the hydrological conditions of the bay, as well as the small pelagics French fishery in order to look for correlations between hydrology, commercial catch and fish aggregation patterns observed by acoustics. We observed the same species or group of species forming different types of aggregation according to habitat. Conversely, the same type of aggregation, associated with a particular habitat, can be produced by different species. The most notorious change observed during the studied period relates to small clupeoids aggregations in the vicinity of the Gironde estuary, whose structure evolved toward a greater fragmentation of shoals (a large number of small size detections) since 2000. Concerning commercial catches, pelagic trawlers fishing in pairs mainly seek for anchovy in the coastal areas, single pelagic trawlers capture mackerel and horse mackerel in deeper waters while purse seiners target mostly sardine near their fishing ports. Because of the coarse spatial resolution of commercial fishing data and the effect of the application of an international fisheries agreement limiting the fishing activity of French pelagic trawlers during spring, only small correlations between captures and types of aggregation were observed.
La participation des petits poissons pélagiques dans les captures est remarquable. Leurs populations sont cependant caractérisées par des importantes fluctuations de biomasse, impactant fortement les pêcheries. Les méthodes et appareils de pêche utilisés pour capturer ces espèces ont évolué dans le sens d'exploiter le comportement grégaire très développé des petits pélagiques. Cette tendance à former de bancs devient alors désavantageuse pour le poisson face à la pêche moderne. Les conditions environnementales et la pêche peuvent affecter le comportement du poisson, en même temps que ce dernier est susceptible d'affecter l'activité halieutique. Le but de cette étude est de caractériser les systèmes agrégatifs des petits poissons pélagiques dans le golfe de Gascogne en étudiant des « images acoustiques », définies comme l'ensemble des échos (couches planctoniques, bancs, cibles isolées) détectés sur une section de radiale de longueur donnée. Nous analysons leur composition en espèces ainsi que leur distribution spatiale et leur évolution au cours du temps. Nous étudions aussi les conditions hydrologiques du golfe, ainsi que la pêcherie française de ces espèces afin de chercher des corrélations entre l'hydrologie, la capture commerciale et les types d'agrégations observés par acoustique. Nous avons observé qu'une espèce est capable de former des agrégations différentes en fonction de l'habitat, et inversement, le même type d'agrégation, associé à un habitat particulier, peut être produit par des espèces différentes. Le changement observé le plus évident concerne les agrégations de petits clupéiformes, dont la structure a évolué vers une plus grande fragmentation des détections (des petits bancs plus nombreux) depuis 2000. Par rapport à la pêche des professionnels, les chalutiers pélagiques en boeufs recherchent en priorité l'anchois dans la zone côtière, les pélagiques simples capturent le chinchard et le maquereau au large et les senneurs recherchent principalement la sardine à proximité des ports de pêche. À cause de la résolution spatiale trop sommaire des données de pêche et l'effet de l'application des accords internationaux limitant l'activité des chalutiers pélagiques au printemps, nous n'avons observé que peu des corrélations entre les captures et les types d'agrégation établis à partir de données issues des campagnes scientifiques.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2008/these-6083.pdf
http://archimer.ifremer.fr/doc/00000/6083/

Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999
Résumé : This paper develops a comparative overview of the development of Fish Aggregating Devices (or fads) by the tropical purse seine fisheries in various ocean areas (Atlantic, Indian, Western and Eastern Pacific Oceans). First, a comparative review of fishery statistics is developed. Recent catches on fads by purse seiners can be estimated at a level of one million tons yearly. This comparison allows to describe the fishing zones and catch trends over time, the species composition and size taken in the various fad fisheries. Skipjack tuna is the dominant species in most fad fisheries, but significant amounts of yellowfin and bigeye are also frequently taken under fads. The paper also presents an overview of various observer data concerning the by-catches of the various fisheries using fads. This comparison allows to estimate the total worldwide yearly by-catches at about 100,000 t, and their species composition in each ocean. The fad technology used in the various oceans by purse seiners is described. The recent use of fads by purse seiners has introduced major uncertainties in most stock assessments, because analyses are hampered by changes in the fishing effort in a fad fishery, by changes in fishing zones and in sizes caught. As a last point, the management of fads presently done or in view by the various tuna bodies are introduced. It appears that the present massive use of fads worldwide is perhaps an unsafe fishing mode, which could produce serious overfishing of many stocks. There is then a consensus that the use of fads needs to be controlled and limited to sustainable biological levels.

Droits : Ifremer
http://archimer.ifremer.fr/doc/00042/15278/12664.pdf
http://archimer.ifremer.fr/doc/00042/15278/

Éditeur(s) : ISTPM
Résumé : The Atlantic and Mediterranean members of the scorpaenidae family have always triggered numerous discussions about their reciprocious congenialities. Back in the (recent) days when the number of species known on the French coasts was still fairly low, the belonging of one species to such or such genus, as Helicolenus (Sebastes) dactylopterus DELAROCHE or Scorpaena maderensis Cuvier and Valenciennes, has been the subject of numerous articles of which the authors' conclusions might differ from one another, and even today light is still far from being shed on those topics. The difficulties met in the determination of scorpaenidae: similar general appearance, subtle differences, impossibility of comparing the samples with the types, incomplete or misinterpreted descriptions, have lead scientists to make hasty determinations resulting in: an even more complicated synonymy and incorrect data about the biogeography of the species. Thereby, the rockfish named Scorpaena rubellio by JORDAN and GUNN (I) is considered as a synonymous of S. maderensis Cuvier Valenciennes by J. R. NORMAN (2), and of S. porcus Linné by H. W. FOWLER (3). Likewise, the dispersion area of S. scrofa in Guinea, Niger and Sainte-Hélène, is caused by its confusion with other species such as S. stephanica, S. angolensis and S. scrofina. (unverified OCR)
Les représentants de la famille des Scorpénidés dans l'Atlantique et la Méditerranée ont toujours donné lieu à de nombreuses discussions au sujet de leurs affinités réciproques. A l'époque encore récente où le nombre des espèces connues des côtes de France était encore très réduit, la place dans tel ou tel genre d'espèces telles que Helicolenus (Sebastes) dactylopterus DELAROCHE ou Scorpaena maderensis Cuvier et Valenciennes, par exemple, ont provoqué des séries d'articles où les conclusions des auteurs successifs n'étaient pas toujours concordantes, et aujourd'hui encore la lumière est loin d'être faite sur bien des points. Les difficultés que l'on rencontre dans la détermination des Scorpénidés : grande ressemblance générale, différences parfois difficiles à saisir, impossibilité de comparer les échantillons d'étude aux types, obligation de se contenter de descriptions incomplètes .ou mal interprétées, ont trop souvent entraîné les chercheurs à des déterminations trop hâtives ayant comme résultats : de compliquer la synonymie et de fausser plus ou moins complètement les données acquises sur la biogéographie d'une espèce. C'est ainsi que la Scorpène appelée Scorpaena rubellio par JORDAN et GUNN (Il est considérée comme synonyme de S. maderensis Cuvier Valenciennes par J. R. NORMAN (2), et de S. porcus Linné par H. W. FOWLER (3). De même l'extension de l'aire de dispersion de S. scrofa en Guinée, au Niger et à Sainte-Hélène, est due à des confusions avec des espèces différentes telles que S. stephanica, S. angolensis et S. scrofina. (OCR non contrôlé)
Revue des Travaux de l'Institut des Pêches Maritimes (0035-2276) (ISTPM), 1943 , Vol. 13 , N. 1-4

Droits : Ifremer
http://archimer.ifremer.fr/doc/1943/publication-3420.pdf
http://archimer.ifremer.fr/doc/00000/3420/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The tropical to warm-temperate marine brown macroalgal genus Lobophora (Dictyotales, Phaeophyceae) recently drew attention because of its striking regional diversity. In this study we reassess Lobophora global species diversity, and species distributions, and explore how historical factors have shaped current diversity patterns. We applied a series of algorithmic species delineation techniques on a global mitochondrial cox3 dataset of 598 specimens, resulting in an estimation of 98–121 species. This diversity by far exceeds traditional diversity estimates based on morphological data. A multi-locus time-calibrated species phylogeny using a relaxed molecular clock, along with DNA-confirmed species distribution data was used to analyse ancestral area distributions, dispersal-vicariance-founder events, and temporal patterns of diversification under different biogeographical models. The origin of Lobophora was estimated in the Upper Cretaceous (−75 to −60 MY), followed by gradual diversification until present. While most speciation events were inferred within marine realms, founder events also played a non-negligible role in Lobophora diversification. The Central Indo-Pacific showed the highest species diversity as a result of higher speciation events in this region. Most Lobophora species have small ranges limited to marine realms. Lobophora probably originated in the Tethys Sea and dispersed repeatedly in the Atlantic (including the Gulf of Mexico) and Pacific Oceans. The formation of the major historical marine barriers (Terminal Tethyan event, Isthmus of Panama, Benguela upwelling) did not act as important vicariance events. Long-distance dispersal presumably represented an important mode of speciation over evolutionary time-scales. The limited geographical ranges of most Lobophora species, however, vouch for the rarity of such events.
ISSN: 1055-7903

hal-01535635
http://hal.upmc.fr/hal-01535635
http://hal.upmc.fr/hal-01535635/document
http://hal.upmc.fr/hal-01535635/file/Vieira_2017_Historical.pdf
DOI : 10.1016/j.ympev.2017.03.007

Éditeur(s) : Société Française d'Ichtyologie
Résumé : In the present paper a new genus, Diretmoides, and a new species, Diretmoides parini, of the berycomorph family Diretmidae is described. The hitherto single genus of the family, Diretmus Johnson, 1863, therefore becomes monotypic while the new genus includes two species pauciradiatus (Woods, 1973) and parini sp. nov. The genus Diretmus is mainly charactcrized by three features (1) by its anus placed immediately anterior to the anal fin, (2) by a prepelvic ridge of ventral scutes and (3) by the high number of bony lamellae on the upper third of the operculum. The species of Diretmoides on the other hand have (1) their anus midway between the pelvics and the anal fin, (2) the ventral midline anterior to their pelvics is flat and is covered by normal body-scales and (3) there are only a few lamellae on the upper third of the operculum. Juveniles of the two Diretmoides-species differ from each other in their colour pattern,the adolescents and adults in meristic characters. All described species live meso-to bathypelagically. D. argenteus is widely distributed in tropical and temperate waters of all oceans. The two Diretmoides -species also live in the Atlantic as well as in the Pacific. However there is only one record of Diretmoides parini and none of D. pauciradiatus from the Indian Ocean. In addition to the described species, indication is given of the presumable existence of a third Diretmoides-species from off Japan. Artificial keys to adults and juveniJes are given at the end of this paper. NOT CONTROLLED OCR
Les auteurs décrivent un nouveau genre, Diretmoides, et une nouvelle espèce, Diretmoides parini. Le genre Diretmus ne comprend plus qu'une seule espèce D. argenteus Johnson, 1863; Diretmoides en comporte deux;D. pauciradiatus (Woods, 1973) d D. parini n.sp. Le genre Diretmus est caractérisé principalement par la position de l'anus juste en avant de l'anale par la présence en avant des pelviennes d'une carène épineuse ventrale et par la densité des lamelles osseuses sur le tiers supérieur de l'opercule. Chez Diretmoides l'anus est à mi-distance entre l'anale et les pelviennes; il n'y a pas de carène épineuse ventrale en avant des pelviennes et, sur le tiers supérieur de l'opercule, les lamelles osseuses sont peu nombreuses et éparses. Les jeunes Diretmoides se distinguent les uns des autres par leur coloration, les adolescents et les adultes par leurs caractères méristiques. Tous les Diretmidés actuellement connus sont des espèces méso à bathypélagiques. D. argenteus est largement distribué dans les eaux tropicales et tempérées de tous les océans. Les deux espèces de Diretmoides ont été signalées dans l'Atlantique et te Pacifique mais on ne connaît qu'une seule capture de D. parini dans l'océan indien et aucune de D. pauciradiatus. En outre. l'étude d'exemplaires provenant du Japon a amené les auteurs à souligner l'existence probable d'une troisième espèce de Diretmoides. Deux clés de détermination, l'une pour les adultes, l'autre pour les jeunes des trois espèces décrites, sont données à la fin de cette note. OCR NON CONTRÔLE
Cybium (Société Française d'Ichtyologie), 1981 , Vol. 5 , N. 1 , P. 33-60

Droits : 1981 Société Française d'Ichtyologie
http://archimer.ifremer.fr/doc/1981/publication-3746.pdf
http://archimer.ifremer.fr/doc/00000/3746/

Éditeur(s) : Gauthier-Villars
Résumé : The littoral area of Benin is a lagoonal-estuarial, indeed even deltaic, environment. Poor in species, the mangrove of Benin belongs to the tropical Atlantic type tending to be humid, considering the "drought belt" which affects this region. It undergoes profound hydrological changes in the course of the different seasons in relation to the Mono and Couffo Rivers. The granulometric analysis and the study of the facies makes clear a lenticular-type sedimentation in relation to numerous and rapid hydrodynamic variations. The clayish quartzose sediment also contains a chemical phase (pyrite is transformed through oxidation into jarosite, gypsum and halite in relation to the micromilieux of evaporation) and an important organic phase - with a pH level ranging from 5 to 6. Kaolinite, from the nearby "Continental terminal", is deposited during calm periods. The smectites seem linked to high energy, sandier deposits and their origin should probably be sought in a far away back country (Eocene, basement).
Oceanologica Acta, Special issue (0399-1784) (Gauthier-Villars), 1982

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00246/35730/34238.pdf
http://archimer.ifremer.fr/doc/00246/35730/

Éditeur(s) : Amer Geophysical Union
Résumé : Since Last Glacial Maximum (23-19 ka), Earth climate warming and deglaciation occurred in two major steps (Bolling-Allerod and Preboreal), interrupted by a short cooling interval referred to as the Younger Dryas (12.5-11.5 ka B. P.). In this study, three cores (MV-33, MV-66, and MD-40) collected in the central part of Pandora Trough (Gulf of Papua) have been analyzed, and they reveal a detailed sedimentary pattern at millennial timescale. Siliciclastic turbidites disappeared during the Bolling-Allerod and Preboreal intervals to systematically reoccur during the Younger Dryas interval. Subsequent to the final disappearance of the siliciclastic turbidites a calciturbidite occurred during meltwater pulse 1B. The Holocene interval was characterized by a lack of siliciclastic turbidites, relatively high carbonate content, and fine bank-derived aragonitic sediment. The observed millennial timescale sedimentary variability can be explained by sea level fluctuations. During the Last Glacial Maximum, siliciclastic turbidites were numerous when the lowstand coastal system was located along the modern shelf edge. Although they did not occur during the intervals of maximum flooding of the shelf (during meltwater pulses 1A and 1B), siliciclastic turbidites reappear briefly during the Younger Dryas, an interval when sea level rise slowed, stopped, or perhaps even fell. The timing of the calciturbidite coincides with the first reflooding of Eastern Fields Reef, an atoll that remained exposed for most of the glacial stages.
Journal Of Geophysical Research-earth Surface (0148-0227) (Amer Geophysical Union), 2008-03-29 , Vol. 113 , N. F01S19 , P. 1-15

Droits : Copyright 2008 by the American Geophysical Union.
http://archimer.ifremer.fr/doc/00079/19014/16592.pdf
DOI:10.1029/2006JF000649
http://archimer.ifremer.fr/doc/00079/19014/

Éditeur(s) : Gauthier-Villars
Résumé : We present results of sequential data assimilation of altimetric data in a linear tropical Atlantic model, using an analysis technique that we have developed. We use sea level anomaly fields obtained from altimetric data of the satellite Geosat. Despite the weak amplitudes of the anomaly fields, we obtain marked improvements of the model simulations due to assimilations. Thus, we show that altimetric data may be very useful for improving model simulations when adapted assimilation techniques are applied.
Oceanologica Acta (0399-1784) (Gauthier-Villars), 1992 , Vol. 15 , N. 5 , P. 525-536

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00101/21179/18796.pdf
http://archimer.ifremer.fr/doc/00101/21179/

Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999
Résumé : The original baitboat fishing technique using a permanent association between the fishing boat and the tuna school has been developed by the baitboat fleet of Dakar, Senegal and is also in use in the Canary Islands. This new fishing technique, the result of 20 years of improvements still on, has induced a dramatic increase of the catch yields which, in turn, has sustained the survival and even a recent development of the fleet. This technique is based on the aggregating behaviour of tropical tunas. However, it contains a dynamic component which is not found in tuna fishing on drifting or anchored fads. The specifications of the method, its refinement over the years and its main consequences for the fishery are described together with the school exchanges between baitboats over months even from one year to the next. Based on the analysis of 1228 recoveries from 5500 tagged fish, tuna movements among associated schools, between associated schools and free schools fished by purse seiners and movements in and out of the baitboat fishing grounds help to better understand the dynamics of tunas and schools of this peculiar tuna association. These data show a very high recovery rate, a remarkable tuna fidelity to the original school for all species, a small number of recoveries within the purse seine catch as well as the rare tuna movements outside the baitboat area. The study highlights the complexity and the numerous consequences of tuna and school behaviour.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00042/15304/12637.pdf
http://archimer.ifremer.fr/doc/00042/15304/