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O. Giere - One of the best experts on this subject based on the ideXlab platform.
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Field distribution and sulphide tolerance of Capitella capitata (Annelida : Polychaeta) around shallow water hydrothermal vents off Milos (Aegean Sea): a new sibling species?
Marine Biology, 1998Co-Authors: Inez Gamenick, Marco Abbiati, O. GiereAbstract:The cosmopolitan polychaete Capitella capitata, known as a complex of opportunistic sibling species, usually dominates the macrobenthos of polluted or unpredictable environments. A population of C. capitata, termed Capitella sp. M, was found in a shallow water hydrothermal vent area south of Milos (Greece). Here, this population occurs close to vent outlets (termed the “transition zone”), an environment with steep gradients of temperature, salinity and pH and increased sulphide concentrations of up to 710 μM. The field distribution of C. capitata in relation to sulphide concentrations around the vent outlets was investigated and sulphide tolerance experiments were conducted on laboratory-cultured worms to elucidate possible adaptations of Capitella sp. M to these extreme environmental conditions. In order to investigate whether the population from the Milos hydrothermal vent area can be considered a distinct sibling species within the C. capitata complex, crossbreeding experiments and analysis of general protein patterns were conducted with Capitella sp. M and three other C. capitata populations of different ecological ranges. Capitella sp. M showed high resistance (median survival time: 107 ± 38 h) to anoxia plus high sulphide concentrations of 740 μM. It seems that the ability to survive high-sulphide conditions in combination with reduced interspecific competition enables the polychaete to maintain a continuous population in this rigorous habitat. From the extremely high tolerance to anoxia and sulphide, shown in both the crossbreeding experiments and the analysis of total proteins, it can be concluded that Capitella sp. M from the Milos hydrothermal vent area represents a separate sibling species within the C. capitata complex.
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{Benthic fauna of a shallow-water gaseohydrothermal vent area in the Aegean Sea (Milos, Greece)}
Marine Biology, 1997Co-Authors: F. Thiermann, Ioanna Akoumianaki, J. A. Hughes, O. GiereAbstract:The benthic community of shallow-water hydrothermal vents (10 m water depth) in a sandy bay on the south coast of Milos, Greece was studied. The macro- and meiofauna, as well as environmental factors such as temperature, salinity, sulfide concentration, grain size composition, ATP concentration, organic carbon, chlorophyll a and phaeopigments were evaluated. Samples were taken along transects from a seagrass meadow into a hydrothermally active area. Hydrothermally active spots were distinguished from the surrounding sediment by their black sediment coloration and an overlying white bacterial mat. For comparison, a control transect from a seagrass meadow into bare sand in a non-vent area in the same bay was studied. Overall, we found decreasing faunal diversity from the seagrass bed towards the hydrothermally active area. Along this gradient, four different zones could be distinguished. (a) The seagrass area had a relatively low diversity compared to the control stations, but much higher diversity than in the areas directly influenced by hydrothermal activity. (b) The border zone between the seagrass and the hydrothermal area, with moderate sulfide concentrations, pH values, seawater salinity and temperatures, was inhabited by an impoverished community dominated by the polychaete Capitella capitata, the nematodes Oncholaimus campylocercoides and Sabatieria sp., and an as yet undescribed chromadorid nematode (Chromadorina sp.). (c) The transition zone at the border of the hydrothermal area proper, with temperatures and sulfide concentrations higher than in the border zone, was characterized by high salinity (60‰) and low pH values. Along with the gastropod Cyclope neritea, single specimens of C. capitata and O. campylocercoides occurred. (d) The hydrothermal area proper, characterized by high sulfide concentrations, had high sediment temperatures and high salinities. The pH was as low as 6. Here, the gastropod Cyclope neritea was the only species occurring in considerable numbers. The gaseohydrothermal activity seems to largely exclude the surrounding fauna in a graded zonal pattern. The increasing hydrothermal stress entrains a change of the ambient biota towards a depauperate consortium of tolerant, opportunistic species, e.g. Capitella capitata (Polychaeta) and Oncholaimus campylocercoides (Nematoda). Although the hydrothermal area proper was characterized by a thick bacterial mat, the benthic community was characterized not by bacteria feeders but by scavenging species.
Valery E. Forbes - One of the best experts on this subject based on the ideXlab platform.
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identification and expression of two novel cytochrome p450 genes belonging to cyp4 and a new cyp331 family in the polychaete Capitella capitata sp i
Biochemical and Biophysical Research Communications, 2004Co-Authors: Hanne Cathrine Bisgaard, Valery E. ForbesAbstract:The polychaete Capitella capitata sp.I has a high capacity to metabolize polycyclic aromatic hydrocarbons (PAHs) which are among the most hazardous environmental pollutants with significant biological effects. In the present study, two novel cytochrome P450 (CYP) genes were identified in this species. One was named CYP331A1, the first member of a new family of CYP331, and the other CYP4AT1 is the first member of a new subfamily CYP4AT. Both of these genes are constitutively expressed in the worms and detectable by RT-PCR. The expression of CYP331A1 mRNA was observed to be more sensitive to PAH exposure than CYP4AT1, which indicated that CYP331A1 should play a more important role than CYP4AT1 in PAH metabolism in this species. Considering the importance of C. capitata sp.I in taking up PAH and other organic pollutants from contaminated marine sediments with the potential for subsequent food-chain transfer, our results are important for understanding the molecular basis of biotransformation and detoxification in this invertebrate, and also have evolutionary significance for understanding the diversity and history of the CYP superfamily.
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Variability in reproductive mode and larval development within the Capitella capitata species complex
Invertebrate Reproduction & Development, 2000Co-Authors: Nuria Méndez, Inez Linke-gamenick, Valery E. ForbesAbstract:Summary A comparative analysis was carried out of reproductive mode, larval development pattern, and larval growth rate under identical conditions of three members of the Capitella capitata species complex: Capitella sp I from New York, US, Capitella sp M from shallow hydrothermal vents off Milos, Greece, and Capitella sp S from an intertidal flat on Sylt, Germany. In addition, three populations from salmon farms, Capitella K (Kilmelford, Scotland), Capitella Cm and Capitella Ct (Cranford, Ireland), are described for the first time. Three development patterns were observed: planktotrophic (Capitella K and Ct populations), lecithotrophic (Capitella spp I, M and Cm populations), and direct development (Capitella sp S). Experiments with planktotrophic larvae from the Capitella K population at different temperatures, in the presence and absence of light and with several kinds of substrate were not successful in inducing settlement, although differences in the duration of larval survival were observed. Overall...
Amaral, Cecília A. Z. - One of the best experts on this subject based on the ideXlab platform.
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Polychaete zonation on sandy beaches of São Sebastião Island, São Paulo State, Brazil
Instituto Oceanográfico da Universidade de São Paulo, 2015Co-Authors: Reis, Margarete De O., Morgado, Eloísa H., Denadai, Márcia R., Amaral, Cecília A. Z.Abstract:This study was performed in the intertidal zone of Barra Velha, Perequê, and Engenho d'Água beaches, located on São Sebastião Island (São Paulo State, Brazil), to assess the composition, abundance, and zonation of the polychaete community in the intertidal zone. Four structurally different sectors were established, two on Barra Velha (I and lI), one on Perequê, and one on Engenho d'Água. Each sector was divided into 3 tidal levels (lower, middle, and upper), in which 5 or 6 random samples were taken seasonally using a corer of 0.01 m2 in area. Laeonereis acuta, Capitella capitata, and Heteromastus filiformis dominated in the upper tidal levels, and Scoloplos (Leodamas) sp. and Cirriformia tentaculata in the lower levels. The structural complexity of Engenho d'Água, caused by rocky fTagments mixed with sand, supported the richest and most diverse polychaete fauna of ali the sectors. The salinity of the interstitial water and the organic matter content were the principal factors related to the zonation patterns at these sites.Este trabalho foi realizado na região entremarés das praias Barra Velha, Perequê e Engenho d'Água, situadas na Ilha de São Sebastião (Estado de São Paulo, Brasil), com o objetivo de estudar a composição, abundância e zonação da taxocenose dos poliquetas. Quatro setores estruturalmente diferentes foram delimitados, sendo dois na Barra Velha (I e II), um no Perequê e um no Engenho d'Água. Cada setor foi dividido em 3 níveis entremarés (inferior, intermediário e superior), nos quais 5-6 amostras aleatórias foram tomadas sazonalmente utilizando um delimitador com 0,01 m2 de área. Laeonereis acuta, Capitella capitata e Heteromastus filiformis ocorreram predominantemente nos níveis superiores e Scoloplos (Leodamas) sp. e Cirriformia tentaculata nos inferiores. A complexidade estrutural do Engenho d' Água, caracterizado por fragmentos rochosos misturados ao sedimento, sustentou a fauna de poliquetas mais rica e diversificada dentre os setores. A salinidade da água intersticial e o teor de matéria orgânica foram os principais parâmetros determinantes da zonação nestes locais.107117Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
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Polychaete zonation on sandy beaches of São Sebastião Island, São Paulo State, Brazil
Instituto Oceanográfico da Universidade de São Paulo, 2015Co-Authors: Reis, Margarete De O., Morgado, Eloísa H., Denadai, Márcia R., Amaral, Cecília A. Z.Abstract:This study was performed in the intertidal zone of Barra Velha, Perequê, and Engenho d'Água beaches, located on São Sebastião Island (São Paulo State, Brazil), to assess the composition, abundance, and zonation of the polychaete community in the intertidal zone. Four structurally different sectors were established, two on Barra Velha (I and lI), one on Perequê, and one on Engenho d'Água. Each sector was divided into 3 tidal levels (lower, middle, and upper), in which 5 or 6 random samples were taken seasonally using a corer of 0.01 m2 in area. Laeonereis acuta, Capitella capitata, and Heteromastus filiformis dominated in the upper tidal levels, and Scoloplos (Leodamas) sp. and Cirriformia tentaculata in the lower levels. The structural complexity of Engenho d'Água, caused by rocky fTagments mixed with sand, supported the richest and most diverse polychaete fauna of ali the sectors. The salinity of the interstitial water and the organic matter content were the principal factors related to the zonation patterns at these sites.Este trabalho foi realizado na região entremarés das praias Barra Velha, Perequê e Engenho d'Água, situadas na Ilha de São Sebastião (Estado de São Paulo, Brasil), com o objetivo de estudar a composição, abundância e zonação da taxocenose dos poliquetas. Quatro setores estruturalmente diferentes foram delimitados, sendo dois na Barra Velha (I e II), um no Perequê e um no Engenho d'Água. Cada setor foi dividido em 3 níveis entremarés (inferior, intermediário e superior), nos quais 5-6 amostras aleatórias foram tomadas sazonalmente utilizando um delimitador com 0,01 m2 de área. Laeonereis acuta, Capitella capitata e Heteromastus filiformis ocorreram predominantemente nos níveis superiores e Scoloplos (Leodamas) sp. e Cirriformia tentaculata nos inferiores. A complexidade estrutural do Engenho d' Água, caracterizado por fragmentos rochosos misturados ao sedimento, sustentou a fauna de poliquetas mais rica e diversificada dentre os setores. A salinidade da água intersticial e o teor de matéria orgânica foram os principais parâmetros determinantes da zonação nestes locais
Inez Gamenick - One of the best experts on this subject based on the ideXlab platform.
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Field distribution and sulphide tolerance of Capitella capitata (Annelida : Polychaeta) around shallow water hydrothermal vents off Milos (Aegean Sea): a new sibling species?
Marine Biology, 1998Co-Authors: Inez Gamenick, Marco Abbiati, O. GiereAbstract:The cosmopolitan polychaete Capitella capitata, known as a complex of opportunistic sibling species, usually dominates the macrobenthos of polluted or unpredictable environments. A population of C. capitata, termed Capitella sp. M, was found in a shallow water hydrothermal vent area south of Milos (Greece). Here, this population occurs close to vent outlets (termed the “transition zone”), an environment with steep gradients of temperature, salinity and pH and increased sulphide concentrations of up to 710 μM. The field distribution of C. capitata in relation to sulphide concentrations around the vent outlets was investigated and sulphide tolerance experiments were conducted on laboratory-cultured worms to elucidate possible adaptations of Capitella sp. M to these extreme environmental conditions. In order to investigate whether the population from the Milos hydrothermal vent area can be considered a distinct sibling species within the C. capitata complex, crossbreeding experiments and analysis of general protein patterns were conducted with Capitella sp. M and three other C. capitata populations of different ecological ranges. Capitella sp. M showed high resistance (median survival time: 107 ± 38 h) to anoxia plus high sulphide concentrations of 740 μM. It seems that the ability to survive high-sulphide conditions in combination with reduced interspecific competition enables the polychaete to maintain a continuous population in this rigorous habitat. From the extremely high tolerance to anoxia and sulphide, shown in both the crossbreeding experiments and the analysis of total proteins, it can be concluded that Capitella sp. M from the Milos hydrothermal vent area represents a separate sibling species within the C. capitata complex.
Marco Abbiati - One of the best experts on this subject based on the ideXlab platform.
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Field distribution and sulphide tolerance of Capitella capitata (Annelida : Polychaeta) around shallow water hydrothermal vents off Milos (Aegean Sea): a new sibling species?
Marine Biology, 1998Co-Authors: Inez Gamenick, Marco Abbiati, O. GiereAbstract:The cosmopolitan polychaete Capitella capitata, known as a complex of opportunistic sibling species, usually dominates the macrobenthos of polluted or unpredictable environments. A population of C. capitata, termed Capitella sp. M, was found in a shallow water hydrothermal vent area south of Milos (Greece). Here, this population occurs close to vent outlets (termed the “transition zone”), an environment with steep gradients of temperature, salinity and pH and increased sulphide concentrations of up to 710 μM. The field distribution of C. capitata in relation to sulphide concentrations around the vent outlets was investigated and sulphide tolerance experiments were conducted on laboratory-cultured worms to elucidate possible adaptations of Capitella sp. M to these extreme environmental conditions. In order to investigate whether the population from the Milos hydrothermal vent area can be considered a distinct sibling species within the C. capitata complex, crossbreeding experiments and analysis of general protein patterns were conducted with Capitella sp. M and three other C. capitata populations of different ecological ranges. Capitella sp. M showed high resistance (median survival time: 107 ± 38 h) to anoxia plus high sulphide concentrations of 740 μM. It seems that the ability to survive high-sulphide conditions in combination with reduced interspecific competition enables the polychaete to maintain a continuous population in this rigorous habitat. From the extremely high tolerance to anoxia and sulphide, shown in both the crossbreeding experiments and the analysis of total proteins, it can be concluded that Capitella sp. M from the Milos hydrothermal vent area represents a separate sibling species within the C. capitata complex.
