30 research outputs found

    Especies de priapúlido, foronídeos y pogonóforos de la Península Ibérica y mares adyacentes

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    Sipuncula de la región magallánica comparada con zonas adyacentes de la Antártida

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    The Magellan sipunculan fauna includes 4 families, 7 genera and 16 species. A comparison between this fauna and that from adjacent regions of Antarctica has been made. A total of 8 species and 3 genera are shared by the compared areas. Univariate analyses show no significant statistical differences among the investigated faunas, whereas a multivariate analysis corroborates that the effects of the Antarctic Convergence are stronger at the level of genera than species. Only 3 genera were able to cross over this zoogeographical boundary. However, these 3 genera succeeded in the new biotopes of Antarctica, since a total of 16 species have been recorded, compared with the 8 species only found in the Magellan region.La fauna magallánica de sipuncúlidos presenta 4 familias, 7 géneros y 16 especies. Se lleva a cabo una comparación entre esta fauna y la procedente de zonas adyacentes de la Antártida. Un total de 8 especies y 3 géneros están presentes en ambas zonas. Los resultados del análisis univariante indican la ausencia de diferencias estadísticas significativas entre las faunas investigadas, mientras que el análisis multivariante revela que los efectos de la Convergencia Antártica son más importantes a nivel de género que de especie. Sin embargo, estos géneros tuvieron cierto éxito en la colonización progresiva de los nuevos biotopos antárticos, dado que se han encontrado un total de 16 especies frente a las 8 exclusivas del área magallánica

    Macrozoobenthic changes on rocky shores of the Bight of Bilbao: 14 years of monitoring biological recovery

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    Benthic communities on rocky shores from the Bight of Bilbao, known as the Abra de Bilbao (northern Spain) and the adjacent coast have been studied during 14 years (1984-1998) within the framework of an environmental monitoring programme for both subtidal and intertidal zones. The study area is now experiencing a process of generalised environmental improvement in its water quality, as a result of the region's industrial recession and the implementation of a comprehensive renovation sewage system, which is still in progress. Biological recovery has been analysed with uni- and multivariate techniques, which make it possible to differentiate several recovery stages, grouped according to the littoral zone sampled. A total of 12 taxa have been selected as characteristics of different environmental situations in space and time, the most sensitive of which are Sagartiidae, Mytilidae, Patellidae and Chthamalidae. The need to use alternative analyses in long term studies of hard bot- tom macrozoobenthos is highlighted. A three-phase conceptual model based on own results and previous works is proposed, which describes the current situation, as well as the recorded or expected changes. The model comprises two parts: a) one for the subtidal and lower intertidal levels, where biotic strategies related to the inverse patterns of fauna and flora dominance are emphasised; b) another for the upper intertidal level, where the appearance and development of a barnacle belt play a crucial role. The model is intended to serve as an environmental tool able to detect changes in the recovery process of the Bight of Bilbao and similar bays elsewhere.Se han estudiado las comunidades bénticas de sustrato rocoso del abra de Bilbao y su costa adyacente durante 14 años (1984-1998), dentro de un programa de seguimiento biológico de los medios submareal e intermareal. El área de estudio se encuentra en un proceso de mejora de la calidad ambiental de sus aguas como consecuencia de la recesión industrial y del Plan Integral de Saneamiento, actualmente en desarrollo. Se ha constatado la recuperación biológica por medio de técnicas univariantes y multivariantes, proponiéndose una serie de etapas en dicha recuperación, diferentes según el nivel litoral. Se ha seleccionado un total de doce taxones como los máximos responsables de discriminar situaciones en el espacio y en el tiempo, entre los que destacan por su mayor sensibilidad: Sagartiidae, Mytilidae, Patellidae y Chthamalidae. Se demuestra, asimismo, la necesidad de utilizar diferentes tipos de análisis en los estudios a largo plazo del macrozoobentos de sustrato rocoso. Con base en estos resultados y en trabajos previos, se articula un modelo conceptual en tres fases, describiendo la situación actual del bentos y los cambios registrados o previsibles. El modelo consta de dos partes: a) el correspondiente a los niveles submareal e intermareal inferior, donde se enfatizan las estrategias relacionadas con los patrones inversos de dominancia de la fauna y la flora; b) el concerniente al nivel intermareal superior, donde desempeñan un papel fundamental la aparición y el desarrollo del cinturón de cirrípedos. De este modo, se pretende dotar a los planes de seguimiento ambiental, tanto del abra de Bilbao como de otras áreas similares, de una herramienta para la detección de cambios en sus planes de recuperación.Instituto Español de Oceanografí

    Detection of blaCTX-M-15 in an integrative and conjugative element in four extensively drug-resistant Haemophilus parainfluenzae strains causing urethritis

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    Haemophilus parainfluenzae is a commensal organism with rising numbers of multidrug-resistant (MDR) strains. This pathogen is of increasing clinical relevance in urogenital infection. The aim of this work was to identify and characterise the molecular mechanisms of resistance associated with four cephalosporin-resistant H. parainfluenzae strains collected from patients with urethritis. Antimicrobial resistance was determined by microdilution following European Committee on Antimicrobial Susceptibility Testing cri-teria. Strains were then analysed by whole-genome sequencing to determine clonal relationship and the molecular basis of antimicrobial resistance. Finally, a phylogenetic analysis was performed on all urogen-ital MDR strains of H. parainfluenzae previously isolated in our hospital. All strains were resistant to ,B- lactams, macrolides, tetracycline, fluoroquinolones, chloramphenicol, cotrimoxazole, and aminoglycosides. The resistance profile was compatible with the presence of an extended-spectrum ,B-lactamase (ESBL). Whole-genome sequencing detected blaCTX-M-15 that conferred high minimum inhibitory concentrations to cephalosporins in two novel integrative and conjugative elements (ICEHpaHUB6 and ICEHpaHUB7) that also harboured a blaTEM-1 ,B-lactamase. This study shows a novel bla CTX-M-15 ESBL carried in an integrative conjugative element in four extensively drug-resistant H. parainfluenzae strains. This resistance determi-nant could be transmitted to other sexually transmitted pathogens and this is a cause for concern. (c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/

    The Magnitude of Global Marine Species Diversity

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    Background: The question of how many marine species exist is important because it provides a metric for how much we do and do not know about life in the oceans. We have compiled the first register of the marine species of the world and used this baseline to estimate how many more species, partitioned among all major eukaryotic groups, may be discovered. Results: There are ∼226,000 eukaryotic marine species described. More species were described in the past decade (∼20,000) than in any previous one. The number of authors describing new species has been increasing at a faster rate than the number of new species described in the past six decades. We report that there are ∼170,000 synonyms, that 58,000–72,000 species are collected but not yet described, and that 482,000–741,000 more species have yet to be sampled. Molecular methods may add tens of thousands of cryptic species. Thus, there may be 0.7–1.0 million marine species. Past rates of description of new species indicate there may be 0.5 ± 0.2 million marine species. On average 37% (median 31%) of species in over 100 recent field studies around the world might be new to science. Conclusions: Currently, between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely. More species than ever before are being described annually by an increasing number of authors. If the current trend continues, most species will be discovered this century

    The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats

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    The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet—undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well

    Proposed conservation of four sipunculan specific names

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    Volume: 44Start Page: 89End Page: 9
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