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Spatio-temporal responses of the intertidal macrobenthic community to the effects of a submarine outfall (SO) and a new sewage treatment plant (EDAR) were evaluated, analyzing changes in macrofaunal assemblages and community structure. Study was conducted in a SW Atlantic coastal area in 4 stages: BSO (Before the SO), Du (During the construction of the SO), ASO (After the SO start-up) and AEDAR (After the treatment plant start-up). Boccardia proboscidea and Brachidontes rodriguezii contributed most to the differences between all stages at the site nearest to the discharge point. Number of individuals was highest at BSO and Du. Richness and diversity were lowest at the BSO and highest at the Du. Furthermore, the richness decreased slightly, and the diversity increased at AEDAR. Evenness was highest at the BSO and AEDAR. The nestedness was the dominant process driving the differences between the BSO stage community and the rest of the stages. SO affects the composition and structure of the intertidal macrobenthic community near the outfall area, as organic matter discharge further offshore favour the development of a more diverse intertidal community, including species sensitive to organic enrichment.

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Submarine outfalls are an effective alternative for the final discharge of wastewater. The aim was to evaluate the subtidal macrobenthic community's responses and the changes in bottom sedimentary dynamics due to submarine outfall (SO) location. Sampling stages were: before SO (BSO), after SO (ASO) and after treatment plant (AEDAR). Sampling sites were determined at different distances from the coastline (coastal, oceanic, and reference) on both sides of the pipe (North and South). Species shifts (from tolerant to sensitive) were observed along with a decrease in organic matter in the AEDAR Stage. There were changes in the sedimentary dynamic with sediment accumulation on the South side of the SO (finest sediments) and erosion on the North side (coarsest sediments) in the ASO and AEDAR Stages. Species turnover was higher than nesting in all stages. Functional trait analysis allowed the identification of temporal variations in benthic communities. The body size, development mode, feeding mode, habit, adult mobility and tolerance to pollution were useful functional traits to detect changes through Stages (BSO, ASO, and AEDAR). Biotic indices classified the sites as slightly disturbed, indicating a slight improvement in the AEDAR Stage.

RESUMO

The present study recorded the abundance of plastic debris in marine sediments of tourist beaches in the Southwest Atlantic (Argentina). We aimed to determine the abundance of macro-, meso- and microplastics in different beaches, considering different anthropogenic and natural factors. Generalized Linear Mixed Models (GLMMs) were performed and the explanatory factors were: Beach Morphology; Grain Size; Recreational Use Level; Continental Water Discharge, Location, Distance Urban Centre and Season. The Continental Water Discharge was the factor responsible for the highest abundance of plastic debris on the beach surface. Beaches with fine granulometry, between groins, with high to very high intensity of recreational use, tend to accumulate and/or retain greater amounts of plastic debris. The seasonal factor influences the abundance of plastic waste in the central zone between the pre-summer and post-summer seasons, despite the cleaning effect of the city goverment. In beaches with greater anthropogenic pressure, the influence of this factor on the abundance of litter is altered.

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Microplastics are currently considered widespread marine pollutants, accumulating in sediments and shorelines around the world. Spatial distribution of microplastics in marine sediments is consequence of a combination of multiple factors (naturals and anthropics). We evaluated the drivers' factors of the abundance and distribution of two microplastics morphotypes (fibers and fragments) in surface sediments (5 cm deep) on SW Atlantic beaches with different plastics waste contribution along the coastline. Beach geomorphology, sediment grain size, distance to the urban area, continental waters discharge and human activities were the analyzed factors. Fibers abundance was significantly highest in pocket beaches, moderately exposed and closest to the urban center, while the fragments abundance was highest in beaches with stormwater outfall. The fine sand and the high recreational level were also factors driving the abundance of both morphotypes. Therefore, plastic morphotype and abundance vary according to the determining factors.

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Introduction: The first open-sea (non-coastal) Marine Protected Area in Argentina, named "Namuncurá I" (NMPA), was created in 2013 at Burdwood Bank (BB), an undersea plateau located about 200 km south from Malvinas Islands (Falkland Islands) and 150 km east from Staten Island, SW Atlantic Ocean. It comprises three different management areas: the central one ("core", strict protection, only control and monitoring activities), surrounded by a "buffer" area (authorized activities, e.g. scientific research) and an external "transition" area (productive and extractive activities contemplated in the Management Plan). Beyond the transition area, only the southern shelf-break is protected, after the creation of the "Namuncurá II" MPA in December 2018. Objective: Provide the inventory of polychaetes collected during 2016 and 2017 at the core (98 m depth), buffer (128 m depth), transition (133 m-189 m depth) areas of the Namuncurá I MPA, together with slope areas (220 m-798 m depth). Methods: Taken with a trawl net used to characterize the faunal assemblages and to compare results with other Magellan areas. Multidimensional Scaling (MDS) and Cluster Analysis (CA) were applied to a Bray-Curtis similarity index to assess polychaete assemblages in the NMPA - BB slope and Magellan region respectively; SIMPER (Similarity Percentage Analyses) and ANOSIM (Analysis of Similarities) were performed. Results: A total of 918 individuals, which correspond to 39 taxa distributed in 22 families, were recorded in samples from NMPA and BB slope, mainly epibenthic or associated with the large corals collected. Ampharete kerguelensis McIntosh, 1885; Hyalinoecia artifex Verrill, 1880; Idanthyrsus macropaleus (Schmarda, 1861); Laetmonice producta Grube, 1877; Onuphis pseudoiridescens Averincev, 1972; Pista mirabilis McIntosh 1885 and Terebellides malvinensis Bremec & Elias, 1999 constitute new records for Burdwood Bank. A similar polychaete assemblage characterized the three areas of NMPA and slope locations, while H. artifex characterized locations at the NW deepest slope of the bank. Conclusions: These results indicate strong connections between the fauna collected at NMPA and the polychaetes assemblage in other Magellan areas dominated by soft bottoms. The biogeographic importance of the BB as connection for benthic polychaete species between South America and the Antarctic Peninsula merits future investigation.

Introducción: La primera Área Marina Protegida de mar abierto (no costera) en Argentina, llamada "Namuncurá I" (AMPN), fue creada en 2013 en el Banco Burdwood (BB), una plataforma sumergida ubicada unos 200 km al sur de las Islas Malvinas y 150 km al Este de la Isla de los Estados. En el Océano Atlántico SO. El área comprende tres diferentes áreas de manejo: la central ("el núcleo", con protección estricta, solo Control y actividades de monitoreo), rodeada por un área "de amortiguación" (solo actividades autorizadas, como investigación científica) y un área externa de "transición" (se contemplan actividades productivas y extractivas en el Plan de Manejo). Más allá del área de transición, el talud y las áreas adyacentes no presentan medidas de protección. Objetivos: Proporcionar un inventario de poliquetos colectados durante 2016 y 2017 en el Núcleo (98 m de profundidad), de Amortiguación (128 m), de Transición (133 m-189 m) y Talud (220 m-798 m). Métodos: Las muestras fueron obtenidas con una red de arrastre para caracterizar las asociaciones faunísticas y para compararlas con otras áreas Magallánicas. Análisis de Escalamiento Multidimensional y de agrupamiento aglomerativo jerárquico fueron aplicados a una matriz de similaridad de Bray-Curtis para determinar las asociaciones de poliquetos en el AMP - Talud del BB y región Magallánica, respectivamente. Resultados: Un total de 918 individuos, que corresponden a 39 taxones distribuidos en 22 familias, fueron registrados en las muestras del AMPN y talud del BB, mayormente epibentónicos o asociados a grandes corales. Ampharete kerguelensis McIntosh, 1885; Hyalinoecia artifex Verrill, 1880; Idanthyrsus macropaleus (Schmarda, 1861); Laetmonice producta Grube, 1877; Onuphis pseudoiridescens Averincev, 1972; Pista mirabilis McIntosh 1885 y Terebellides malvinensis Bremec & Elias, 1999 constituyen nuevos registros para el Banco Burdwood. Un ensamble de poliquetos similar caracteriza a las tres áreas del AMPN y talud, mientras que H. artifex caracteriza los sitios más profundos del talud del banco. Conclusiones: Estos resultados indican una fuerte conexión entre la fauna colectada en el NMPA y los ensambles de poliquetos de sustratos blandos de otras áreas Magallánicas. La importancia biogeográfica del BB como una conexión entre Sudamérica y la Península Antártica justifican futuras investigaciones.

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Introduction: The taxonomy of Cirratulidae is not easy due to the diagnostic characters currently accepted change through ontogeny, in some cases, there are even difficulties to separate juveniles from adults. Among the Cirratulus species cited, described and considered as valid for Argentina are Cirratulus jucundus (Kinberg, 1866), Cirratulus patagonicus (Kinberg, 1866) and Cirratulus mianzanii Saracho Bottero, Elías & Magalhães, 2017. Objetive: This study made a revision of Cirratulus includes material deposited in the Museo de Ciencias Naturales de La Plata (MLP) and specimens collected privately by J.M. Orensanz that was donated to the laboratory of Bioindicadores Bentónicos of the National University of Mar del Plata. Methods: The specimens were examined with optical equipment (microscope and stereomicroscope) and also by a scanning electron microscope (SEM). Results: A complete examination of the material, revealed a higher number of species than those already mentioned. In the present work, three new species are described from the intertidal and subtidal areas of the Argentine continental shelf: Cirratulus orensanzii n. sp.; Cirratulus knipovichana n. sp. and Cirratulus alfonsinae n. sp. Conclusions: The knowledge about the taxonomy of the family as well as the updating of the geographic registries contributes to the biodiversity of the region, which is of great importance to carry out both ecological studies and conservation plans.

Introducción: La taxonomía de Cirratulidae no es fácil debido a que los caracteres diagnósticos actualmente aceptados cambian a través de la ontogenia; en algunos casos, incluso existen dificultades para separar a los juveniles de los adultos. Entre las especies de Cirratulus citadas, descritas y consideradas como válidas para Argentina se encuentran Cirratulus jucundus (Kinberg, 1866), Cirratulus patagonicus (Kinberg, 1866) y Cirratulus mianzanii Saracho Bottero, Elias & Magalhães, 2017. Objetivo: El presente estudio hace una revisión de Cirratulus que incluye material depositado en el Museo de Ciencias Naturales de La Plata (MLP) y especímenes recolectados en privado por JM Orensanz que fue donado al laboratorio de Bioindicadores Bentónicos de la Universidad Nacional de Mar del Plata. Métodos: Las muestras se examinaron con equipo óptico (microscopio y estereomicroscopio) y también con microscopio electrónico de barrido (SEM). Resultados: Un examen completo del material, reveló un mayor número de especies que las ya mencionadas. En el presente trabajo, se describen tres nuevas especies de las áreas intermareales y submareales de la plataforma continental argentina: Cirratulus orensanzii n. sp.; Cirratulus knipovichana n. sp. y Cirratulus alfonsinae n. sp. Conclusiones: El conocimiento sobre la taxonomía de la familia, así como la actualización de los registros geográficos, contribuye a la biodiversidad de la región, lo cual es de gran importancia para llevar a cabo estudios ecológicos y planes de conservación.

RESUMO

Introduction: The knowledge of polychaetes in the subtropical region of Africa benefited from the activity of J. Day. However, 50 years after the publication of his Monograph of the Polychaeta of southern Africa, it is necessary to reconsider the identity of the Cirratulidae due to changes in the diagnostic characters and new approaches to the taxonomy of the group to corroborate the status of cosmopolitan species in this region. Objective: We hypothesize that biodiversity of multitentacular Cirratulidae polychaetes has been significantly underestimated in southern Africa. Methods: The present work analyzes material deposited in the Iziko museum, as well as recently collected specimens, using scanning electron microscope to identify them. Results: The material corresponds to two new species belonging to the genus Protocirrineris. Protocirrineris strandloperarum sp. nov. is characterized by having the tentacular filaments between the chaetigers 5 to 10-12 and the first pair of branchiae from chaetiger 7, and P. magalhaesi sp. nov. is characterized by having tentacular filaments between chaetigers 4-8 and the first pair of branchiae from chaetigers 2 or 3. Descriptions of these species, with light and scanning electron microscope images, are given. Schematic drawings of the two new species are shown comparatively with diagnostic characters. Conclusions: The use of new techniques enables discovery of new taxonomic characters and two new species of the genus. The diversity of Cirratulidae polychaetes is underestimated also in the subtropical and tropical regions of Africa.

Introducción: El conocimiento de los poliquetos de la región subtropical de África fue logrado gracias a John Day. Sin embargo, 50 años después es necesario reconsiderar la identidad de los Cirratulidae, debido a los cambios en los caracteres diagnósticos y a las nuevas herramientas de análisis. Objetivo: Nuestra hipótesis es que la biodiversidad de los poliquetos cirratulidos multitentaculares ha sido subestimada significativamente en el sur de África. Métodos: El trabajo actual analiza muestras tomadas recientemente y material depositado en el museo de Iziko con microscopia electrónica de barrido para su identificación. Resultados: El material corresponde a dos especies nuevas, Protocirrineris strandloperarum sp. nov. y Protocirrineris magalhaesi sp. nov. Una imagen esquemática con los caracteres diagnósticos es dada para las especies descriptas en este trabajo. Conclusiones: el uso de nuevas técnicas permitió descubrir nuevos caracteres diagnósticos y dos nuevas especies del género. La diversidad de Cirratulidae también está subestimada en la región subtropical y tropical de África.

RESUMO

Introduction: Brazil has more than 8 000 km of coastline but its marine invertebrates are still poorly known. The cirratulid polychaetes have been an especially neglected group because of its challenging taxonomy. Objective: To describe a new species of Protocirrineris. Methods: In a recent survey in two of the largest Brazilian bays, Todos os Santos Bay and Camamu Bay, 84 specimens of four morphotypes of the multitentaculate genus Protocirrineris were collected. Because of the lack of modified chaetae, the taxonomy of Protocirrineris is challenging and only two of these morphotypes are herein described as new species. Results: These two new species are characterized by having tentacular filaments in two groups over chaetigers 3-4 and first branchiae present from chaetiger 1. They differ from each other in relation to the nature of the achaetigerous region, posterior region, ultrastructure of capillary chaetae and methyl green staining pattern. Two incomplete specimens are also considered as Protocirrineris, and brief descriptions are given. Conclusions: The genus Protocirrineris is cited for the first time in Brazil. Four new morphotypes were found in two large estuaries of Brazil, and two new species are formally described.

Introducción: Brasil tiene más de 8000 km de costa, pero sus invertebrados marinos aún son poco conocidos. Los poliquetos cirratulidos han sido un grupo especialmente descuidado debido a su desafiante taxonomía. Objetivos: Identificar morfotipos de Cirratulidae multitentaculados y encontrar nuevos caracteres diagnósticos. Métodos: En muestreo reciente en dos de las bahías más grandes de Brasil, Bahía de Todos los Santos y Bahía de Camamu, se colectaron cuatro morfotipos del género multitentaculado Protocirrineris. Resultados: Debido a la falta de quetas modificada, la taxonomía de Protocirrineris es un desafío y solo dos de estos morfotipos se describen aquí como nuevas especies. Estas dos nuevas especies se caracterizan por tener filamentos tentaculares en dos grupos sobre los quetígeros 3-4 y las primeras branquias presentes de quetígero 1. Se diferencian entre sí en relación con la naturaleza de la región sin quetas, región posterior, ultraestructura de las quetas capilares y el patrón de tinción con verde de metilo. Dos especímenes incompletos también se consideran Protocirrineris, y se dan breves descripciones. Conclusiones: Se cita por primera vez la presencia del género Protocirrineris en Brasil. Cuatro morfotipos del género han sido encontrados en dos grandes estuarios de Brasil. Dos especies nuevas para la ciencia son descriptas.

RESUMO

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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A large number multitentaculate cirratulids have been described worldwide but most are only known through the original descriptions. Type material, voucher and recently collected specimens from Brazil were revisited in order to reveal their true identity and confirm the records of widely distributed species in this region. Six species are described, three of which are new, Cirriformia capixabensis sp. nov., Cirriformia chicoi sp. nov. and Timarete ceciliae sp. nov. COI and 16S sequences were obtained and used for inter-specific comparisons. Timarete caribous is reported from several localities along the Brazilian coast and a new synonym, Cirratulus melanacanthus, is proposed. The species Timarete oculata, originally described from Brazil and lumped into the Timarete filigera species complex, is herein revalidated and redescribed. The occurrence of the species Timarete filigera and Cirriformia tentaculata is not confirmed from the Brazilian coast. Descriptions, illustrations and a key to genera and species are provided.

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We evaluated benthic habitat quality along a presumed contamination gradient in the Mar del Plata port (Southwestern Atlantic) by coupling biological and chemical proxies in a multidisciplinary approach. Organic matter and photosynthetic pigment contents were higher in silty-clay bottoms of the inner port sites. Levels of all fecal steroids decreased from the inner sites to the port inlet. High concentrations of coprostanol in the inner sites seemed to derive from a permanent population of sea lions rather than from sewage outfalls due to coprostanol/epicoprostanol ratio (IV) values <2.5. PAHs levels were also higher in the inner sector, related to both biomass combustion and petroleum combustion associated to local marine traffic. High disturbance and low ecological status were reflected in low benthic diversity and high AMBI values in the inner sites.

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In order to understand changes in the functioning and the community structure of intertidal ecosystem in sewage-impacted sites, a long-term monitoring coverage study (2004-2011) was carried out on abrasion platforms of the SW Atlantic. The intertidal zone is characterized by the mytilid Brachidontes rodriguezii, an ecosystem engineer. Since the austral spring of 2008, a demographic explosion of an invader polychaetes, Boccardia proboscidea, has produced massive biogenic structures around the sewage discharge outfall. Cover percentage of this polychaete reached almost 100% in sewage-impacted sites but low or no coverage at all in Reference Sites. The density of B. rodriguezii declined due to the biogenic reefs stifles these mytilids. The massive settlement of B. proboscidea among mussels, the rapid growth and the tube construction smothers the mussels in sewage-impacted sites.

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Caulleriella bremecae and C. galeanoi (Polychaeta: Cirratulidae) are newly described from Mar del Plata, Argentina (38ºS, 57ºW). Both species have small, red-pigmented nuchal organs (lateral "eyes") on the prostomium. Caulleriella bremecae sp. nov. is further characterized by a peristomium without annulations except for a narrow anterior dorsal fold, posterior part of peristomium extending posterodorsally over chaetiger 1, latter extending posterodorsally over chaetiger 2 and with slightly separated grooved palps arising middorsally; notochaetae of chaetigers 1-23 all smooth capillaries, thereafter with six bidentate sigmoid hooks and 3-4 capillaries, both types fewer on last 4-5 chaetigers; neurochaetae of chaetigers 1-2 comprised of 8 bidentate hooks and 1-2 capillaries, thereafter only bidentate hooks, decreasing in number posteriorly. The species is frequent and abundant throughout the year in the intertidal mussel beds situated 200-700m from the sewage outfall of Mar del Plata city. Caulleriella galeanoi sp. nov. is characterized by a peristomium with three annulations dorsally, with grooved palps arising from annulus 3, and by smooth capillary chaetae in noto- and neuropodia of chaetigers 1-2. Bidentate hooks are present in neuropodia from chaetiger 3, numbering 5-6 in anterior and middle chaetigers, 1-3 in posterior ones. Notopodia have 3-6 pairs of smooth capillary chaetae, decreasing in number posteriorly. From chaetiger 13-20, notopodia with 1-2 capillary chaetae and 1-2 bidentate hooks. Specimens held in aquaria supplied with water and the green alga Vaucheria sp. (Vaucheriaceae) from the intertidal zone reproduced asexually by fission. Gametes were not observed in any specimens.

As espécies novas Caulleriella bremecae e C. galeanoi (Polychaeta: Cirratulidae) são descritas para a região de Mar del Plata, Argentina (38ºS, 57ºW). Ambas têm pequenos órgãos nucais prostomiais de cor vermelha. Cauleriella bremecae sp. nov. é diagnosticada pela presença de peristômio sem anelações, com exceção de uma estreita dobra antero-dorsal; parte posterior do peristômio projetando-se posterodorsalmente sobre o setígero 1, que por sua vez se estende sobre a metade antero-dorsal do setígero 2; setígero 1 com palpos sulcados, em posição médio-dorsal, ligeiramente separados entre si; notocerdas dos setígeros 1-23 todas capilares lisas, substituídas a seguir por 6 ganchos sigmóides bidentados e 3-4 capilares, em menor número nos 4-5 últimos setígeros; neurocerdas dos setígeros 1-2 incluem 8 ganchos bidentados e 1-2 capilares, a seguir apenas ganchos bidentados, cujo número decresce posteriormente. A espécie é constante (?) e abundante ao longo de todo o ano em bancos de mexilhões na região entre marés, a 200-700 metros do ponto de despejo do duto de esgotos de Mar del Plata. Caulleriella galeanoi sp. nov. é diagnosticada por um peristômio com 3 anelações dorsais, com palpos sulcados inseridos na terceira anelação; cerdas capilares lisas nos notopódios e neuropódios dos setígeros 1-2; 5-6 ganchos bidentados neuropodiais a partir do setígero 3, diminuindo para 1-3 nos setígeros posteriores; notopódios anteriores com 3-6 pares de cerdas capilares lisas, presentes em menor número nos notopódios posteriores. A partir dos setígeros 13-20, notopódios com 1-2 cerdas capilares e 1-2 ganchos bidentados. Exemplares mantidos em aquários com a clorofícea Vaucheria sp reproduziram-se assexuadamente por fissão. Não foram observados gametas.

RESUMO

Caulleriella bremecae and C. galeanoi (Polychaeta: Cirratulidae) are newly described from Mar del Plata, Argentina (38ºS, 57ºW). Both species have small, red-pigmented nuchal organs (lateral "eyes") on the prostomium. Caulleriella bremecae sp. nov. is further characterized by a peristomium without annulations except for a narrow anterior dorsal fold, posterior part of peristomium extending posterodorsally over chaetiger 1, latter extending posterodorsally over chaetiger 2 and with slightly separated grooved palps arising middorsally; notochaetae of chaetigers 1-23 all smooth capillaries, thereafter with six bidentate sigmoid hooks and 3-4 capillaries, both types fewer on last 4-5 chaetigers; neurochaetae of chaetigers 1-2 comprised of 8 bidentate hooks and 1-2 capillaries, thereafter only bidentate hooks, decreasing in number posteriorly. The species is frequent and abundant throughout the year in the intertidal mussel beds situated 200-700m from the sewage outfall of Mar del Plata city. Caulleriella galeanoi sp. nov. is characterized by a peristomium with three annulations dorsally, with grooved palps arising from annulus 3, and by smooth capillary chaetae in noto- and neuropodia of chaetigers 1-2. Bidentate hooks are present in neuropodia from chaetiger 3, numbering 5-6 in anterior and middle chaetigers, 1-3 in posterior ones. Notopodia have 3-6 pairs of smooth capillary chaetae, decreasing in number posteriorly. From chaetiger 13-20, notopodia with 1-2 capillary chaetae and 1-2 bidentate hooks. Specimens held in aquaria supplied with water and the green alga Vaucheria sp. (Vaucheriaceae) from the intertidal zone reproduced asexually by fission. Gametes were not observed in any specimens.

As espécies novas Caulleriella bremecae e C. galeanoi (Polychaeta: Cirratulidae) são descritas para a região de Mar del Plata, Argentina (38ºS, 57ºW). Ambas têm pequenos órgãos nucais prostomiais de cor vermelha. Cauleriella bremecae sp. nov. é diagnosticada pela presença de peristômio sem anelações, com exceção de uma estreita dobra antero-dorsal; parte posterior do peristômio projetando-se posterodorsalmente sobre o setígero 1, que por sua vez se estende sobre a metade antero-dorsal do setígero 2; setígero 1 com palpos sulcados, em posição médio-dorsal, ligeiramente separados entre si; notocerdas dos setígeros 1-23 todas capilares lisas, substituídas a seguir por 6 ganchos sigmóides bidentados e 3-4 capilares, em menor número nos 4-5 últimos setígeros; neurocerdas dos setígeros 1-2 incluem 8 ganchos bidentados e 1-2 capilares, a seguir apenas ganchos bidentados, cujo número decresce posteriormente. A espécie é constante (?) e abundante ao longo de todo o ano em bancos de mexilhões na região entre marés, a 200-700 metros do ponto de despejo do duto de esgotos de Mar del Plata. Caulleriella galeanoi sp. nov. é diagnosticada por um peristômio com 3 anelações dorsais, com palpos sulcados inseridos na terceira anelação; cerdas capilares lisas nos notopódios e neuropódios dos setígeros 1-2; 5-6 ganchos bidentados neuropodiais a partir do setígero 3, diminuindo para 1-3 nos setígeros posteriores; notopódios anteriores com 3-6 pares de cerdas capilares lisas, presentes em menor número nos notopódios posteriores. A partir dos setígeros 13-20, notopódios com 1-2 cerdas capilares e 1-2 ganchos bidentados. Exemplares mantidos em aquários com a clorofícea Vaucheria sp reproduziram-se assexuadamente por fissão. Não foram observados gametas.

RESUMO

The polychaete composition and distribution within mussel beds were studied in order to assess organic pollution due to domestic sewage in a rocky shore of Mar del Plata (Argentina) during 1997. Four stations and a control site were randomly sampled around the local effluent. Quantitative data on polychaetes, as well as sediment accumulated among mussels and its organic carbon content were measured. Polychaete distribution patterns are related to the organic matter gradient, being Capitella cf. capitata, Neanthes succinea (Frey & Leuckart, 1847) and Boccardia polybranchia (Haswell, 1885) the dominant indicator species close to the effluent. At medial distances, the cirratulids Caulleriella alata (Southern, 1914) and Cirratulus cirratus (Müller, 1776) are very important in abundance. The syllids Syllis prolixa Ehlers, 1901 and S. gracilis Grube, 1840 are distributed along the study area, but dominate at the medial stations and at the control site. The orbiniid Protoariciella uncinata Hartmann-Schröder, 1962 is subdominant at the control station.

RESUMO

The polychaete composition and distribution within mussel beds were studied in order to assess organic pollution due to domestic sewage in a rocky shore of Mar del Plata (Argentina) during 1997. Four stations and a control site were randomly sampled around the local effluent. Quantitative data on polychaetes, as well as sediment accumulated among mussels and its organic carbon content were measured. Polychaete distribution patterns are related to the organic matter gradient, being Capitella cf. capitata, Neanthes succinea (Frey & Leuckart, 1847) and Boccardia polybranchia (Haswell, 1885) the dominant indicator species close to the effluent. At medial distances, the cirratulids Caulleriella alata (Southern, 1914) and Cirratulus cirratus (Müller, 1776) are very important in abundance. The syllids Syllis prolixa Ehlers, 1901 and S. gracilis Grube, 1840 are distributed along the study area, but dominate at the medial stations and at the control site. The orbiniid Protoariciella uncinata Hartmann-Schröder, 1962 is subdominant at the control station.

RESUMO

The polychaete composition and distribution within mussel beds were studied in order to assess organic pollution due to domestic sewage in a rocky shore of Mar del Plata (Argentina) during 1997. Four stations and a control site were randomly sampled around the local effluent. Quantitative data on polychaetes, as well as sediment accumulated among mussels and its organic carbon content were measured. Polychaete distribution patterns are related to the organic matter gradient, being Capitella cf. capitata, Neanthes succinea (Frey & Leuckart, 1847) and Boccardia polybranchia (Haswell, 1885) the dominant indicator species close to the effluent. At medial distances, the cirratulids Caulleriella alata (Southern, 1914) and Cirratulus cirratus (Müller, 1776) are very important in abundance. The syllids Syllis prolixa Ehlers, 1901 and S. gracilis Grube, 1840 are distributed along the study area, but dominate at the medial stations and at the control site. The orbiniid Protoariciella uncinata Hartmann-Schröder, 1962 is subdominant at the control station.