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Introduction: The bivalve Semimytilus patagonicus is a potentially useful bioindicator because of its feeding mechanism, and the worm Pseudonereis gallapagensis is also interesting as a bioindicator because it is benthonic, abundant, and a food source for the squid Doryteuthis gahi. However, their sensitivity to contaminants has not been sufficiently studied. Objective: To test the usefulness of the mussel Semimytilus patagonicus and the polychaete Pseudonereis gallapagensis as ecotoxicological tools for detergents in the marine environment. Methods: We used 120 individuals of S. patagonicus from Miraflores and 120 of P. gallapagensis from Barranco (both near the city of Lima, Peru). For the bioassays, we used two anionic detergents (active ingredient, ai, Sodium Dodecylbenzene Sulfonate). For S. patagonicus, with an average valve length of 32.3 ± 6.4 mm, we tested "Double power Ariel®" (90 %) at concentrations of 17.5, 35, 70 and 140 mg ai l-1, evaluated after 48 and 72 h of exposure; and for P. gallapagensis, with a total body length of 20.4 ± 8.8 mm, we tested "Caricia®" at 62.5, 125, 250, 500 and 1 000 mg of ai l-1 at 24, 48 and 72 h of exposure. Results: The LC50 values (Mean Lethal Concentration) were 34.95 mg ia l-1 for S. patagonicus and 102.48 mg ia l-1 for P. gallapagensis at 72 h of exposure. The detergents were toxic for S. patagonicus and slightly toxic for P. gallapagensis. The risk classification for S. patagonicus is "harmful" and for P. gallapagensis "not classifiable". Conclusions: These two bioindicators allow evaluating the acute toxicity of SDBS-based commercial detergents in the marine aquatic environment.

Introducción: El bivalvo Semimytilus patagonicus es un bioindicador potencialmente útil por su mecanismo de alimentación, y el gusano Pseudonereis gallapagensis también es interesante como bioindicador por ser bentónico, abundante y fuente de alimento para el calamar Doryteuthis gahi. Sin embargo, su sensibilidad a los contaminantes no ha sido suficientemente estudiada. Objetivo: Probar la utilidad del mejillón S. patagonicus y el poliqueto P. gallapagensis como herramientas ecotoxicológicas para detergentes en el medio marino. Métodos: Se utilizaron 120 individuos de S. patagonicus de Miraflores y 120 de P. gallapagensis de Barranco (ambos cerca de la ciudad de Lima, Perú). Para los bioensayos se utilizaron dos detergentes aniónicos (ingrediente activo, ia, dodecilbenceno sulfonato de sodio). Para S. patagonicus, con una longitud valver promedio de 32.3 ± 6.4 mm, probamos Ariel Doble Poder® (90 %) a concentraciones de 17.5, 35, 70 y 140 mg·ia·l-1, evaluadas a las 48 y 72 h de exposición; y para P. gallapagensis, con una longitud corporal total de 20.4 ± 8.8 mm, probamos Caricia® a 62.5, 125, 250, 500 y 1 000 mg·ia·l-1 a las 24, 48 y 72 h de exposición. Resultados: Los valores de CL50 (Concentración Letal Media) fueron de 34.95 mg·ia·l-1 para S. patagonicus y 102.48 mg·ia·l-1 para P. gallapagensis a las 72 h de exposición. Los detergentes fueron tóxicos para S. patagonicus y levemente tóxicos para P. gallapagensis. La clasificación de riesgo para S. patagonicus es "nocivo" y para P. gallapagensis "no clasificable". Conclusiones: Estos dos bioindicadores permiten evaluar la toxicidad aguda del detergente comercial a base de SDBS en el ambiente acuático marino.

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Polychaetes of the spionid genus Trochochaeta occur mainly in the northern hemisphere, including North and Central America. In South America, they have been reported only from the northeast region of Brazil - Sergipe and Paraíba - despite numerous biological investigations around the continent. In 2006, a dense population (up to 7000 individuals per square meter) of Trochochaeta was discovered in the estuary of Santos, São Paulo, Brazil, hosting the busiest container sea port in Latin America, and in 2008, one Trochochaeta specimen was found in Camamu Bay, Bahia. We identify these worms as Trochochaeta japonica Imajima, 1989 and describe and illustrate their morphology. This is the first record of the species from outside of its type locality in Honshu, Japan. It might have been introduced to the estuary of Santos as larvae in ballast water of ocean-going vessels. We review the systematics of Trochochaeta and provide an identification key to 12 currently recognized species.

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The estuaries of the Aconcagua and Maipo Rivers of central Chile are receptors of residues that contain metals from anthropic activities including agriculture, mining and smelters, which have different levels in the two basins. This study postulates that the exposition to metals is different in the two estuaries and that their sediments contain bioavailable chemical agents that produce oxidative stress. The aim of the study was to evaluate the effect of estuarine sediments on the polychaete Perinereis gualpensis using oxidative stress biomarkers and to determine the metal concentrations in sediments and their accumulation in P. gualpensis. Sediments and organisms were collected in December 2015 and January 2016 in the estuaries. The Catapilco estuary was used as control, since its basin has little anthropic activity. The metal concentrations of Fe Cu, Pb, Zn and Cd were determined in tissues of the organisms and in sediments. The granulometry, conductivity, redox potential, pH and organic matter in sediments were determined, as well as catalase activity and lipid peroxidation. The results show that the concentrations of metals in sediments were higher in the estuary of the Aconcagua River: Cu: 48 ± 2µgg-1; Fe: 154 ± 19mgg-1, Pb: 20 ± 3µgg-1 and Zn: 143 ± 20µgg-1. In tissues, Pb and Fe were higher in the estuary of the Maipo River, while Cd was detected only in the Catapilco River mouth. Catalase activity was greater in the estuary of the Aconcagua River and lipid peroxidation in the estuary of the Catapilco River. Significant regressions were found between biomarkers of oxidative stress and metal concentrations in tissues of P. gualpensis. In conclusion, the sediments of the studied estuaries contain bioavailable chemical agents that provoke oxidative stress in P. gualpensis, which may be a risk for the benthic communities of these ecosystems. This species is proposed to monitor metals bioavailability and oxidative stress in estuarine sediments.

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Sternaspis chilensis n. sp. is described based on specimens collected in channels and fjords of southern Chile and previously identified as Sternaspis scutata (Ranzani, 1817), originally described from the Meditarrean Sea. Sternaspis chilensis n. sp. is described based on the features of the shield with anterior margins rounded and anterior depression shallow; marginal shield chaetal fascicles arranged with an inverted C-shaped pattern; and distribution of the integument papillae. Sternaspis chilensis is widely distributed in the Magellan Province from Estero Reloncaví (41°32'54"S, 72°19'48"W) to Strait of Magellan (53°34'S, 70°04'W), between 50 and 515 m depth.

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Perhaps the most widely used quantitative approach in metacommunity ecology is the estimation of the importance of local environment vs. spatial structuring using the variation partitioning framework. Contrary to metapopulation models, however, current empirical studies of metacommunity structure using variation partitioning assume a space-for-dispersal substitution due to the lack of analytical frameworks that incorporate patch connectivity predictors of dispersal dynamics. Here, a method is presented that allows estimating the relative importance of environment, spatial variation and patch connectivity in driving community composition variation within metacommunities. The proposed approach is illustrated by a study designed to understand the factors driving the structure of a soft-bottom marine polychaete metacommunity. Using a standard variation partitioning scheme (i.e. where only environmental and spatial predictors are used), only about 13% of the variation in metacommunity structure was explained. With the connectivity set of predictors, the total amount of explained variation increased up to 51% of the variation. These results highlight the importance of considering predictors of patch connectivity rather than just spatial predictors. Given that information on connectivity can be estimated by commonly available data on species distributions for a number of taxa, the framework presented here can be readily applied to past studies as well, facilitating a more robust evaluation of the factors contributing to metacommunity structure.

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Annelid disparity has resulted in morphological-based classifications that disagree with phylogenies based on Sanger sequencing and phylogenomic analyses. However, the data used for the latter studies came from various sources and technologies, involved poorly occupied matrices and lacked key lineages. Here, we generated a new Illumina-based data set to address annelid relationships from a fresh perspective, independent from previously generated data and with nearly fully occupied matrices. Our sampling reflects the span of annelid diversity, including two symbiotic annelid groups (Myzostomida and Spinther) and five meiofaunal groups once referred to as part of Archiannelida (three from Protodrilida, plus Dinophilus and Polygordius). As well as the placement of these unusual annelids, we sought to address the overall phylogeny of Annelida, and provide a new perspective for naming of major clades. Our results largely corroborate the phylogenomic results of Weigert et al. (2014; Illuminating the base of the annelid tree using transcriptomics. Mol Biol Evol. 31:1391-1401), with "Magelona + Owenia" and Chaetopteridae forming a grade with respect to all other annelids. Echiura and Sipuncula are supported as being annelid groups, with Sipuncula closest to amphinomids as sister group to Sedentaria and Errantia. We recovered the three Protodrilida terminals as sister clade to Phyllodocida and Eunicida (=clade Aciculata). We therefore place Protodrilida as part of Errantia. Polygordius was found to be sister group to the scaleworm terminal and the possibility that it is a simplified scaleworm clade, as has been shown for the former family Pisionidae, is discussed. Our results were equivocal with respect to Dinophilus, Myzostomida, and Spinther possibly owing to confounding long-branch effects.

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In Mar del Plata (Argentine, SW Atlantic), a large seaside resort, the sewage discharges impact the littoral ecosystem. The invader polychaete Boccardia proboscidea has developed reefs since spring of 2008. The effect of this species on the richness, diversity and structure of epilithic intertidal community was assessed through an MBACI design in both sewage-impacted and reference sites, and Before/After the invasion. The presence of reefs of B. proboscidea since spring 2008 has caused a significant reduction of total individuals, total taxa and diversity in sewage-impacted sites regarding the reference ones. The species analyzed showed a high variable response because patterns were dominated by small-scale variability. Occasional peaks in abundance were observed on a single sampling site and time and a large variation among replicates. The associated fauna, formerly rich and diverse in impacted sites, shows a tendency to disappear as the ecosystem engineer Brachidontes rodriguezii is replaced by monocultures of B. proboscidea.

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In this paper, a literature review was conducted to characterize the knowledge produced about the group Annelida Polychaeta in the state of Maranhão, indicating gaps and possibilities for study, besides rescuing its diversity, listing the recorded species and the environments in which they occur. This study was conducted by search databases, academic libraries and private collections of researchers who have produced work about the group. The scientific production related to polychaetes is dominated by informally published material (92.3%) and majority of the studies analyzed (75.6%) was not specifically about the group Polychaeta, but on benthic macrofauna, with predominance of work in mangroves environments (59.6%). A total of 99 genera, 32 families and 38 taxa was identified to the species level recorded for Maranhão. The knowledge of the polychaetous fauna is still incipient, requiring greater investment and intensification of studies. Thus, this literature review contributes towards synthesizing the knowledge produced about the polychaetes, seeking to find the gaps and provide basis for future studies to be conducted in Maranhão.

Neste artigo, realizou-se uma revisão de literatura para caracterizar a produção científica referente ao grupo Annelida Polychaeta no estado do Maranhão, indicando lacunas e possibilidades de estudo, além de resgatar a sua diversidade, listando as espécies registradas e os ambientes onde ocorrem. Este estudo foi realizado por meio de busca em bases de dados, bibliotecas acadêmicas e acervos particulares de pesquisadores que produziram trabalhos sobre o grupo. A produção científica relacionada aos poliquetas é constituída principalmente por trabalhos não-publicados (92,3%). A maioria dos estudos analisados (75,6%)não tratava especificamente sobre o grupo Polychaeta, mas sobre macrofauna bêntica. Em relação ao ambiente de estudos que abriga maior quantidade de informação, predominou o manguezal, representando 59,6% dos trabalhos. A análise dos registros permitiu quantificar um total de 32 famílias e 99 gêneros, dos quais 38 táxons foram identificados em nível de espécie. Observou-se que o conhecimento sobre a fauna poliquetológica maranhense ainda é incipiente, necessitando de maior investimento e intensificação dos estudos. Assim, esta revisão de literatura contribui no sentido de sintetizar o conhecimento produzido sobre os poliquetas, buscando encontrar as lacunas e dar base para estudos futuros a serem realizados no Maranhão.

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In this paper, a literature review was conducted to characterize the knowledge produced about the group Annelida Polychaeta in the state of Maranhão, indicating gaps and possibilities for study, besides rescuing its diversity, listing the recorded species and the environments in which they occur. This study was conducted by search databases, academic libraries and private collections of researchers who have produced work about the group. The scientific production related to polychaetes is dominated by informally published material (92.3%) and majority of the studies analyzed (75.6%) was not specifically about the group Polychaeta, but on benthic macrofauna, with predominance of work in mangroves environments (59.6%). A total of 99 genera, 32 families and 38 taxa was identified to the species level recorded for Maranhão. The knowledge of the polychaetous fauna is still incipient, requiring greater investment and intensification of studies. Thus, this literature review contributes towards synthesizing the knowledge produced about the polychaetes, seeking to find the gaps and provide basis for future studies to be conducted in Maranhão.(AU)

Neste artigo, realizou-se uma revisão de literatura para caracterizar a produção científica referente ao grupo Annelida Polychaeta no estado do Maranhão, indicando lacunas e possibilidades de estudo, além de resgatar a sua diversidade, listando as espécies registradas e os ambientes onde ocorrem. Este estudo foi realizado por meio de busca em bases de dados, bibliotecas acadêmicas e acervos particulares de pesquisadores que produziram trabalhos sobre o grupo. A produção científica relacionada aos poliquetas é constituída principalmente por trabalhos não-publicados (92,3%). A maioria dos estudos analisados (75,6%)não tratava especificamente sobre o grupo Polychaeta, mas sobre macrofauna bêntica. Em relação ao ambiente de estudos que abriga maior quantidade de informação, predominou o manguezal, representando 59,6% dos trabalhos. A análise dos registros permitiu quantificar um total de 32 famílias e 99 gêneros, dos quais 38 táxons foram identificados em nível de espécie. Observou-se que o conhecimento sobre a fauna poliquetológica maranhense ainda é incipiente, necessitando de maior investimento e intensificação dos estudos. Assim, esta revisão de literatura contribui no sentido de sintetizar o conhecimento produzido sobre os poliquetas, buscando encontrar as lacunas e dar base para estudos futuros a serem realizados no Maranhão.(AU)

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The genus Ficopomatus (Serpulidae) consists of sessile, tubicolous polychaete annelid worms that may colonize a diversity of substrata, and tolerate considerable variations in salinity. Thus, members of this genus, including Ficopomatus uschakovi, in some cases are exotic and maybe invasive. The purpose of our research was to collect and identify marine organisms associated with the submerged roots of mangrove trees in the Gulf of Urabá, Colombian Caribbean, South America. Within the Gulf, there is a well-developed forest of the Red Mangrove, Rhizophora mangle, along the margins of El Uno Bay. We sampled the roots of R. mangle from five stations of the bay, and we identified specimens of F. uschakovi from each of those stations. Ficopomatus uschakovi was found to be more abundant in regions of the bay that exhibit the lowest salinity. Based on a morphological comparison of the present specimens with the original species description, revised descriptions, and other records from the Indo-West Pacific, Mexican Pacific, and Venezuelan and Brazilian Caribbean, we suggest that F. uschakovi has a broader geographical distribution. Furthermore, because of this broad distribution, and the observed tolerance for low salinity in our study, we also suggest that F. uschakovi is a euryhaline species. It is also likely that F. uschakovi will be found in other localities in the Gulf of Urabá, and in other regions of the Colombian Caribbean. Thus, this record extends the distribution of the species to the Colombian Caribbean, giving the species a continuous distribution across the northern coast of South America.

ResumenEl género Ficopomatus, familia Serpulidae, está compuesto por gusanos poliquetos tubícolas y sésiles que pueden colonizar gran cantidad de sustratos y tolerar variaciones considerables de salinidad. Así, los miembros de éste género, incluyendo Ficopomatus uschakovi, en algunos casos pueden ser considerados exóticos y tal vez invasores. El propósito de nuestra investigación fue recolectar e identificar los organismos marinos asociados a raíces sumergidas de árboles de mangle rojo, Rhizophora mangle, en el golfo de Urabá, Caribe colombiano, Suramérica. Dentro del golfo de Urabá, existe un bosque bien desarrollado de R. mangle, a lo largo de las márgenes de la bahía El Uno. Se tomaron muestras de mangle rojo en cinco estaciones y seidentificó a F. uschakovi para cada una de ellas. Esta especie exhibió mayor abundancia en zonas de la bahía con menor salinidad. Basados en la similitud morfológica que exhiben los ejemplares con la descripción original de la especie, descripciones revisadas e identificaciones reportadas en el oeste del Indopacífico, Pacífico mexicano y la zona Caribe de Venezuela y Brasil, sugerimos que F. uschakovi tiene una amplia distribución geográfica. Además, por esta amplia distribución y la tolerancia observada a bajas concentraciones salinas en nuestro estudio, sugerimos que F. uschakovi es una especie eurihalina. También es probable que F. uschakovi se pueda encontrar en otras localidades en el golfo de Urabá, y en otras regiones del Caribe colombiano. Este registro amplía la distribución de la especie al Caribe colombiano, lo cual demuestra una continuidad en la costa norte de Suramérica.

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The genus Amphictene is reported for the first time from Mexico. Previous records for America are restricted to Brazil (Amphictene catharinensis) (Grube, 1870), and Guatemala (Amphictene guatemalensis) (Nilsson, 1928). In this paper we describe a new species, Amphictene helenae sp. n., characterized by the presence of three pairs of tentacular cirri, while other species have only two pairs. The new species is closely similar to Amphictene catharinensis, and can be distinguished by the presence of a circular group of glandular papillae inserted between the lines of glandular cirri present from the second segment. Amphictene guatemalensis is redescribed based on type material; it differs from the new species in the presence of two pairs of tentacular cirri on segments 1 and 2, six pairs of glandular cirri on the third segment, and four glandular lobes fused in pairs on the fourth segment.

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Fullerene (nC60) and nanosilver (nAg) are nanomaterials with bactericide properties. The increments in their use raise questions about their potential environmental impacts, including estuarine ones. The polychaete Laeonereis acuta (Nereididae) secretes mucus that is colonized by bacteria communities. We analyzed the antioxidant and oxidative damage responses of anterior, middle and posterior region of L. acuta and bacteria communities after nC60 or nAg exposure during 24 h. Molecular analysis showed a prevalence of Vibrio genera in the communities. Bacteria biomass was lowered in worms exposed to 1.0 mg/L of nAg. nC60 reduced total antioxidant capacity of bacteria from worms exposed to 0.1 mg/L. Worms anterior region presented lower antioxidant capacity after exposure to 1.0 mg nC60/L, and the same was observed in the posterior region of worms exposed to 1.0 mg nAg/L. Lipid peroxidation was reduced in the anterior region of worms exposed to nC60 and the opposite was observed in the posterior region.

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The species of the genus Notopygos Grube, 1855 are characterized by an ovate body, a prominent caruncle with three lobes, dendritic branchiae, and double dorsal cirri. Twenty-two species belonging to Notopygos have been described, mostly from the Indo-Pacific region. In America, few species are frequently recorded: Notopygos crinita Grube, 1855 from St. Helena Island (Atlantic) and Notopygos ornata Grube and Ørsted in Grube 1857 from Costa Rica (Pacific). Notopygos crinita is a widely distributed species in the Western Atlantic with additional reports in the Mediterranean Sea (as a questionable alien species) and in the Pacific Ocean. However, only the genus features have been considered, consequently some records could be misidentifications. During a revision of materials from collections and the barcode project, 'Mexican Barcode of Life, MEXBOL', we found specimens of Notopygos megalops and an undescribed species from reef zones in the Caribbean; the former had been considered a junior synonym of Notopygos crinita. Herein, Notopygos megalops is reestablished and Notopygos caribeasp. n. is described. A morphological and DNA barcode approach was used to explain the records of Notopygos ornata in the Atlantic and to show the differences with the new species, since both species share features such as complex pigmentation patterns, and circular projections in the median lobe of the caruncle.

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The sabellariid Phragmatopoma caudata (Kroyer, 1856), Morch, 1863 is widely distributed in the Americas and constructs large reef agglomerates that provide substrates for other benthic species. However, the difficulty in obtaining size data (especially length) hampers population studies, making it necessary to carry out morphometric studies as basis for studies of population dynamics. The objective of the present study is to determine the best morphological descriptor of length in P. caudata. A total of 17 morphometric variables were measured in specimens from four different populations. Measurements were performed using an ocular micrometer attached to a stereoscopic microscope. Correlations in the dataset were tested using Pearson's linear correlation coefficient, and the hypothesis of morphometric differences among populations was tested using MANOVA and principal component analysis. Correlation coefficients were different amongst populations, as well as in the measured traits . Moreover, the results suggest that populations differ more strongly in body size than in shape. Although populations presented different morphometric relationships, the length of the first thoracic chaetiger was one of the variables with highest correlation with total length. This result, as well as the fact that such region is located on the anterior portion of the body, suggests that this structure is a good length descriptor in P. caudata.

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The sabellariid Phragmatopoma caudata (Kroyer, 1856), Morch, 1863 is widely distributed in the Americas and constructs large reef agglomerates that provide substrates for other benthic species. However, the difficulty in obtaining size data (especially length) hampers population studies, making it necessary to carry out morphometric studies as basis for studies of population dynamics. The objective of the present study is to determine the best morphological descriptor of length in P. caudata. A total of 17 morphometric variables were measured in specimens from four different populations. Measurements were performed using an ocular micrometer attached to a stereoscopic microscope. Correlations in the dataset were tested using Pearson's linear correlation coefficient, and the hypothesis of morphometric differences among populations was tested using MANOVA and principal component analysis. Correlation coefficients were different amongst populations, as well as in the measured traits . Moreover, the results suggest that populations differ more strongly in body size than in shape. Although populations presented different morphometric relationships, the length of the first thoracic chaetiger was one of the variables with highest correlation with total length. This result, as well as the fact that such region is located on the anterior portion of the body, suggests that this structure is a good length descriptor in P. caudata.

RESUMO

The sabellariid Phragmatopoma caudata (Kroyer, 1856), Morch, 1863 is widely distributed in the Americas and constructs large reef agglomerates that provide substrates for other benthic species. However, the difficulty in obtaining size data (especially length) hampers population studies, making it necessary to carry out morphometric studies as basis for studies of population dynamics. The objective of the present study is to determine the best morphological descriptor of length in P. caudata. A total of 17 morphometric variables were measured in specimens from four different populations. Measurements were performed using an ocular micrometer attached to a stereoscopic microscope. Correlations in the dataset were tested using Pearson's linear correlation coefficient, and the hypothesis of morphometric differences among populations was tested using MANOVA and principal component analysis. Correlation coefficients were different amongst populations, as well as in the measured traits . Moreover, the results suggest that populations differ more strongly in body size than in shape. Although populations presented different morphometric relationships, the length of the first thoracic chaetiger was one of the variables with highest correlation with total length. This result, as well as the fact that such region is located on the anterior portion of the body, suggests that this structure is a good length descriptor in P. caudata.

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The condition index (CI) of oysters represents an ecophysiological approach to estimate meat quality and yield in cultured bivalve mollusks. In the present study, the CI of oysters from a heavy-metal polluted bay was analyzed with respect to Zn and Cd contamination in soft tissues, spawning, and polychaete infestation. The CI was calculated through a new technique based on molds made to measure the volume of oyster-shell internal cavities. The higher CI values (over 9 in the dry season) were probably related availability of suspended particles rich in organic matter in the bay, while the rapid reduction in the CI from one season to the next at some stations suggests the effect of spawning. Polychaete infestation was considered low (18.7%) and produced no clear CI effects. The Cd in the oyster tissue collected during the rainy season was weak, although still significantly correlated with the CI (r = -0.36; p 0.05). All other comparisons of CI and metal concentrations demonstrated a non-significant correlation. The CI variations observed on the temporal and spatial scale were likely to have been caused by availability of organic matter and spawning, rather than spionid infestation or metal body burdens.

O índice de condição (IC) de ostras é um índice ecofisiológico utilizado para avaliar a qualidade e a produtividade em cultivos de bivalves. No presente estudo, o IC de ostras de uma baía contaminada por metais pesados foi analisado em relação ao conteúdo de Zn e Cd nos tecidos moles, à liberação de gametas após o período reprodutivo e à infestação por poliquetas. O IC foi calculado com uma nova técnica que utiliza moldes da cavidade interna da concha para medir seu volume. Os maiores valores de IC (acima de 9 na estação seca) podem estar relacionados à disponibilidade de material particulado em suspensão rico em matéria orgânica na baía, enquanto a rápida redução do IC observada de uma temporada a outra em algumas estações é um provável efeito da liberação de gametas. A infestação por poliquetas foi considerada baixa (18,7%) e não apresenta efeitos claros no IC. Apenas Cd nos tecidos de ostras coletadas durante a estação das chuvas apresentou correlação baixa, porém significativa (r = -0,36; p 0,05), com o IC. Todas as outras correlações entre metais e IC foram estatisticamente não significativas. As variações do IC observadas em escala espacial e temporal parecem ser causadas mais pela disponibilidade de material particulado rico em material orgânico e pela liberação de gametas do que pela infestação por poliquetas e acúmulo de metais nos tecidos.