133 research outputs found

    Biogeographical homogeneity in the eastern Mediterranean Sea - I: the opisthobranchs (Mollusca: Gastropoda) from Lebanon

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    A reviewed knowledge of the opisthobranch species from Lebanon (eastern Mediterranean Sea), based on literature records (scattered throughout various papers published over a period of more than 150 years) and recently collected material (1999-2002 within the CEDRE framework and other samples), is presented, yielding a total number of 35 taxa recorded from the Lebanese shores identified to species level. Special emphasis has mainly been given to the alien species, for which scattered notes are also given. The known opisthobranch biota is composed of 22 native (~ 63%), 12 alien (~ 34%) and one cryptogenic (~ 3%) taxa. Eleven of these (Berthella aurantiaca, B. ocellata, Aplysia fasciata, Felimare picta, Felimida britoi, F. luteorosea, F. purpurea, Phyllidia flava, Dendrodoris grandiflora, D. limbata and Aeolidiella alderi) constitute new records for the Lebanese fauna, whilst the examined material of a further seven species (Elysia grandifolia, Pleurobranchus forskalii, Aplysia dactylomela, Bursatella leachii, Syphonota geographica, Goniobranchus annulatus, Flabellina rubrolineata) anecdotally cited from Lebanon on the basis of the samples here studied, is here first explained. One additional taxon belonging to the genus Haminoea has been identified to genus level only. Despite the searching effort poning the basis of the material analyzed here, data reported clearly suggest that strong investments are still needed for a better understanding of the eastern Mediterranean opisthobranch fauna

    Leve diferenciación genética entre los límites occidental y oriental de distribución de Astroides calycularis (Pallas, 1776) (Anthozoa, Scleractinia, Dendrophylliidae), inferida a partir de secuencias de COI e ITS

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    Understanding population genetic structure and differentiation among populations is useful for the elaboration of management and conservation plans of threatened species. In this study, we use nuclear and mitochondrial markers (internal transcribed spacers -ITS and cytochrome oxidase subunit one -COI) for phylogenetics and nested clade analyses (NCA), thus providing the first assessment of the genetic structure of the threatened Mediterranean coral Astroides calycularis (Pallas, 1766), based on samples from 12 localities along its geographic distribution range. Overall, we found no population differentiation in the westernmost region of the Mediterranean; however, a slight differentiation was observed when comparing this region with the Tyrrhenian and Algerian basins.El estudio de la estructura de las poblaciones y su diferenciación a nivel genético es de gran utilidad para la elaboración de planes de manejo y conservación de especies amenazadas. En este estudio, utilizamos marcadores nucleares y mitocondriales (espaciadores internos de genes ribosomales -ITS y citocromo oxidasa, subunidad I -COI) y métodos de análisis filogenéticos y de clados anidados (NCA), para realizar la primera valoración de la estructura genética del coral naranja Astroides calycularis (Pallas, 1766), una especie amenazada del Mediterráneo, a partir de muestras de 12 localidades a lo largo de su área de distribución. En las localidades situadas en la región más occidental del Mediterráneo se encontró cierta homogeneidad genética, mientras que al comparar estas localidades con las de las cuencas argelina y del mar Tirreno se observó una ligera diferenciación

    Sea level rise in the Mediterranean Sea: High resolution constraints from vermetid reefs

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    The Mediterranean Sea (MS), is extremely sensitive to rising sea-levels (SL) as attested by drowned archeological remains from the Roman Period. Due to theabsence of coral reefs, evidence for recent and Holocene SL change has so far mainly been restricted to coastal cores archeological remains and submerged speleothem deposits. Vermetid reefs are an extremely sensitive high resolution carbonate archive and they are mainly formed in the lower intertidal zone by gregarious and sessile gastropods belonging to the genus Dendropoma (family Vermetidae). Since their interval of growth is restricted to the tidal zone, they can be used as precise SL proxies (about ±0.1 m in lowrange tidal areas). Here, we report new SL data covering two time-windows: between 2,380 and 1,520 years cal BP and during the last 300 yrs. These data have been obtained from two quasi-stable areas of the Western MS: S. Vito Lo Capo (N Sicily, Italy)and Cabo de Gata(SE Spain), opening new perspectives to understand the response of the global changes on this semienclosed basin

    Elaboració d'una web per facilitar la comprensió dels mecanismes biològics implicats en la reproducció humana

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    Els mecanismes biològics implicats, tant en la formació de gàmetes masculines i femenines com en la fecundació, són molt complexes. Per tal de facilitar la seva comprensió hem elaborat una pàgina web que inclou material bàsic, microfotografies, esquemes, representacions animades i pel·lícules. La majoria del material introduït és inèdit o propi, doncs la recerca de l'equip que ha elaborat la web s'inclou dins del camp de la Reproducció Humana.A més, per augmentar l'interès de l'alumnat, hem afegit a la web el tema de la Reproducció Assistida. Gràcies als coneixements bàsics, els nostres estudiants, podran entendre millor els fonaments i les diferents estratègies emprades actualment en la Reproducció Humana Assistida. A la vegada, també s'han inclòs temes estretament relacionats com les principals causes d'infertilitat humana, el consell genètic o el diagnòstic pre-concepcional, pre-implantacional i pre-natal. Donat l'enorme interès social del tema creiem que aquesta web serà consultada no únicament pel nostre alumnat sinó també per alumnes d'altres Facultats de la UAB i d'altres Universitats Catalanes

    Environmental drivers of distribution and reef development of the Mediterranean coral Cladocora caespitosa

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    Cladocora caespitosa is the only Mediterranean scleractinian similar to tropical reef-building corals. While this species is part of the recent fossil history of the Mediterranean Sea, it is currently considered endangered due to its decline during the last decades. Environmental factors affecting the distribution and persistence of extensive bank reefs of this endemic species across its whole geographic range are poorly understood. In this study, we examined the environmental response of C. caespitosa and its main types of assemblages using ecological niche modeling and ordination analysis. We also predicted other suitable areas for the occurrence of the species and assessed the conservation effectiveness of Mediterranean marine protected areas (MPAs) for this coral. We found that phosphate concentration and wave height were factors affecting both the occurrence of this versatile species and the distribution of its extensive bioconstructions in the Mediterranean Sea. A set of factors (diffuse attenuation coefficient, calcite and nitrate concentrations, mean wave height, sea surface temperature, and shape of the coast) likely act as environmental barriers preventing the species from expansion to the Atlantic Ocean and the Black Sea. Uncertainties in our large-scale statistical results and departures from previous physiological and ecological studies are also discussed under an integrative perspective. This study reveals that Mediterranean MPAs encompass eight of the ten banks and 16 of the 21 beds of C. caespitosa. Preservation of water clarity by avoiding phosphate discharges may improve the protection of this emblematic species.Spanish Ministry of Economy and Competitiveness [CTM2014-57949-R]info:eu-repo/semantics/publishedVersio

    European Red List of Habitats Part 1. Marine habitats

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    The European Red List of Habitats provides an overview of the risk of collapse (degree of endangerment) of marine, terrestrial and freshwater habitats in the European Union (EU28) and adjacent regions (EU28+), based on a consistent set of categories and criteria, and detailed data and expert knowledge from involved countries1. A total of 257 benthic marine habitat types were assessed. In total, 19% (EU28) and 18% (EU28+) of the evaluated habitats were assessed as threatened in categories Critically Endangered, Endangered and Vulnerable. An additional 12% were Near Threatened in the EU28 and 11% in the EU28+. These figures are approximately doubled if Data Deficient habitats are excluded. The percentage of threatened habitat types differs across the regional seas. The highest proportion of threatened habitats in the EU28 was found in the Mediterranean Sea (32%), followed by the North-East Atlantic (23%), the Black Sea (13%) and then the Baltic Sea (8%). There was a similar pattern in the EU28+. The most frequently cited pressures and threats were similar across the four regional seas: pollution (eutrophication), biological resource use other than agriculture or forestry (mainly fishing but also aquaculture), natural system modifications (e.g. dredging and sea defence works), urbanisation and climate change. Even for habitats where the assessment outcome was Data Deficient, the Red List assessment process has resulted in the compilation of a substantial body of useful information to support the conservation of marine habitats
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