El mejillón Semimytilus patagonicus (Mytilida: Mytilidae) y el gusano Pseudonereis gallapagensis (Phyllodocida: Nereididae) como herramientas ecotoxicológica para la contaminación por detergentes en ambientes marinos / The mussel Semimytilus patagonicus (Mytilida: Mytilidae) and the worm Pseudonereis gallapagensis (Phyllodocida: Nereididae) as ecotoxicological tools for detergent pollution in marine environments

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.

The effect of seasonal and human pressure on macrobenthic fauna in the Caroni Swamp Ramsar Site, Trinidad and Tobago / Efecto de la presión estacional y humana en la fauna macrobentónica del sitio Ramsar pantano Caroní, Trinidad y Tobago

Abstract Human pressures have placed many tropical estuaries in developing countries under increased levels of stress. The Caroni Swamp Ramsar Site, the largest mangrove swamp along the west coast of Trinidad, has been subjected to high levels of anthropogenic impacts including hydrological alteration and pollution from land-based sources since the 1920's. While most of these impacts have been well documented, limited information exists on the macrobenthic communities in the swamp. This study addresses the paucity of information. The macrobenthic fauna in the main waterways of Caroni Swamp was sampled at 12 locations using a Van Veen 0.025 m2 grab, once in the dry (April) and wet (August) season of 2015 with a total of 144 samples. The samples were sorted, counted and species were identified to the lowest possible taxonomic level. A total of 55 taxa were identified with polychaetes being the most abundant taxa. The ecological status of the macrobenthos was assessed using AZTI's Marine Biotic Index (AMBI) and the multivariate-AMBI (M-AMBI). Physicochemical parameters were measured with a YSI multiparameter metre. Chemical analyses were also conducted on nitrates, nitrites, ammonia and reactive phosphates using standard methods. Overall, AMBI characterised the Caroni Swamp as "slightly disturbed" with a macrobenthic community of "poor" ecological status according to M-AMBI. Generally, the quality of the environment improves from the dry season to the wet season. However, seasonal variations in AMBI and M-AMBI were found to be site specific as some showed improvement in ecological status and macrozoobenthos quality while others showed degradation from the dry season to the wet season. The stations to the North of the swamp showed improvement from the dry season to the wet season while the opposite was observed in the more Southern stations. One notable characteristic of the swamp was the high levels of pollutants, particularly ammonia, recorded in one of its major waterways, the Caroni River. This is in contrast to the other waterways within the swamp which experience much lower levels of pollutant input from land-based sources. The assessment of the Caroni Swamp using AMBI and M-AMBI may be useful for informing management strategies to conserve the wetland and improve environmental quality. Rev. Biol. Trop. 66(3): 1101-1117. Epub 2018 September 01.

Resumen Los estuarios tropicales de países en desarrollo han experimentado un aumento en los niveles de estrés debido a la presión humana. El sitio Ramsar pantano Caroní, el manglar más grande de la costa oeste de Trinidad, ha estado sujeto a altos niveles de impacto antropogénico, incluyendo alteraciones hidrológicas y contaminación de fuentes terrestres desde la década de 1920. Aunque la mayoría de estos impactos han sido bien documentados, existe información limitada sobre las comunidades macrobentónicas en el pantano. Este estudio aborda esta escasez de información. Se muestreó la fauna macrobentónica en el canal principal del pantano Caroní en 12 localidades utilizando una draga Van Veen de 0.025 m2, una vez durante la época seca (Abril) y la época lluviosa (Agosto) 2015, con un total de 144 muestras. Las muestras fueron ordenadas, contadas y las especies se identificaron al menor nivel taxonómico posible. Se identificaron un total de 55 taxa, siendo los poliquetos el taxa más abundante. El estatus ecológico del macrobentos se evaluó utilizando el Índice Marino Biótico de AZTI (AMBI) y el AMBI-multivariado (M-AMBI). Los parámetros fisicoquímicos se midieron con un multiparámetro YSI. Los análisis químicos también se realizaron para nitratos, nitritos, amonio y fostatos activos utilizando métodos estándar. En conjunto, el índice AMBI caracterizó el pantano Caroní como "levemente alterado" con una comunidad macrobentónica de categoría "pobre" de acuerdo al M-AMBI. Generalmente, la calidad de los ambientes incrementa desde la época seca hasta la época lluviosa. Sin embargo, las variaciones estacionales en los índices AMBI y M-AMBI fueron específicas a la localidad, mostrando algunas un incremento en el estatus ecológico y calidad del macrozoobentos, mientras que otros mostraron una degradación de la época seca a la época lluviosa. Las estaciones al norte del pantano mostraron una mejora de la época seca a la época lluviosa, mientras que se presentó lo contrario en las estaciones más al sur. Una característica notable del pantano fueron los altos niveles de contaminantes, particularmente amonio, registrado en uno de los canales principales del río Caroní. Esto contrasta con los otros canales del pantano que experimentan niveles menores de aporte de contaminantes de fuentes terrestres. La evaluación del pantano Caroní utilizando los índíces AMBI y M-AMBI puede ser una base útil de información para las estrategias de manejo y conservación del humedal y mejorar su calidad ambiental.

Interstitial annelids from the Caribbean Coast of Colombia / Anélidos intersticiales de la costa Caribe de Colombia

Abstract A total of 298 species of polychaetes have been recorded from Colombia. However, only the family Protodrilidae has been reported from the marine interstitial realm. We here aim at identifying the interstitial annelids inhabiting the sandy beaches in Santa Marta region to the most accurate taxonomic level based on light microscopy examinations. Our samples, collected from the intertidal zone at three touristic beaches in the department of Magdalena (Santa Marta Bay, Rodadero Bay, and Taganga Bay), yielded a total of 83 specimens, which we assigned to five families, ten genera and nine species. From those, two families, eight genera, and the species Hesionides gohari, Neogyptis mediterranea, Neopetitia amphophthalma, Westheidesyllis gesae, and Syllis beneliahuae represent new records for the Colombian fauna. This survey should be considered as a first step towards a complete knowledge of the Colombian diversity of interstitial annelids, and our results significantly contribute to fill the gap of our current knowledge, suggesting a high diversity of species comparable to this in better-known areas of the Caribbean and the Atlantic coasts of Brazil. A brief diagnosis, comments on distribution and ecology, and remarks are provided for each record, in order to facilitate the re-identification of the species. Rev. Biol. Trop. 66(2): 658-673. Epub 2018 June 01.

Resumen Un total de 298 especies de poliquetos han sido registradas para Colombia. Sin embargo, solo la familia Protodrilidae ha sido reportada para el medio marino intersticial. El objetivo de este estudio fue identificar los anélidos intersticiales que habitan en playas arenosas de la región de Santa Marta hasta la categoría taxonómica más precisa, basados en observaciones al microscopio de luz. Las muestras fueron recolectadas en la zona intermareal de tres playas turísticas en el departamento del Magdalena (La bahía de Santa Marta, bahía de Rodadero y bahía de Taganga), resultando un total de 83 especímenes, los cuales fueron asignados a cinco familias, diez géneros y nueve especies. De estos, dos familias, ocho géneros y las especies Hesionides gohari, Neogyptis mediterranea, Neopetitia amphothalma, Westheidesyllis gesae y Syllis beneliahuae representan nuevos registros para la fauna de Colombia. Este trabajo debería ser considerado como el primer paso hacia el conocimiento de la diversidad de anélidos intersticiales en Colombia y los resultados contribuyen significativamente a llenar el vacío de información en el tema, sugiriendo una alta diversidad de especies comparable con la de áreas mejor conocidas del Caribe y de la costa atlántica de Brasil. En este trabajo se provee una breve diagnosis, comentarios sobre la distribución y ecología, y anotaciones para cada registro, con el propósito de facilitar la re-identificación de las especies.

Some intertidal and shallow water polychaetes of the Caribbean coast of Costa Rica / Poliquetos de la zona intermareal y aguas someras de la costa del Caribe costarricense

Abstract:The polychaete fauna of the Caribbean coast of Costa Rica has been inadequately characterized with only nine species previously reported. Collections of polychaetes from intertidal coralline rocks and several shallow sub-tidal sites on the Caribbean coast of Costa Rica have been examined and 68 species were identified. Of these, 66 are new records for Costa Rica. Rev. Biol. Trop. 65 (1): 127-152. Epub 2017 March 01.

ResumenLa fauna de poliquetos en la costa del Caribe costarricense se ha descrito inadecuadamente con solo 9 especies reportadas anteriormente. Se estudiaron los poliquetos de de las rocas coralinas intermereales y varios sitios submareales someros en la costa del Caribe costarricense y se identificaron 68 especies, de las cuales 66 son nuevos registros para Costa Rica.

Morphological distinction between estuarine polychaetes: Laeonereis culveri and L. nota (Phyllodocida: Nereididae) / Distinción morfológica de dos poliquetos neréididos estuarinos: Laeonereis culveri (Webster, 1879) y L. nota (Treadwell, 1941)

AbstractThe family Nereididae includes more than 500 polychaete species described worldwide, and includes species common in many benthic environments, but some other species may tolerate freshwater or can even thrive in humid substrates in tropical forests. In estuarine environments, nereidid polychaetes can be abundant and relevant as a food source for resident or migratory birds. Laeonereis culveri (Webster, 1879) is a common estuarine species found in tropical and subtropical Atlantic American shores and was described from New Jersey; its median and posterior parapodia have upper notopodial ligules usually longer than the lower ones, and the latter are parallel to the notaciculae throughout the body. L. culveri distribution is from Connecticut to central Argentina; however, this wide distribution might be due to the inclusion of several other species as junior synonyms, despite that some morphological differences were found between them. One of such species is L. nota (Treadwell, 1941), that was described from Texas; its parapodia have notopodial ligules of about the same size, and the lower ones are oblique to the notaciculae. In order to clarify the differences between these two species, and to define which inhabits the Northwestern Caribbean region, topotype materials from these two species and specimens from Chetumal Bay were collected, and their morphological features were compared. Our results indicated that L. culveri and L. nota are different species and that the latter is found in Chetumal Bay. On the basis of mature specimens, L. culveri is hereby restricted to the Northern Gulf of Mexico and Northwestern Atlantic Ocean, and L. nota is reinstated and its distribution extends from Texas, in the Gulf of Mexico to Chetumal Bay, in the Northwestern Caribbean Sea. A key to identify all species in Laeonereis Hartman (1945) is also included.

ResumenLa familia Nereididae incluye especies comunes y frecuentes en muchos ambientes bénticos y cuenta con más de 500 especies en todo el mundo, y algunas pueden tolerar ambientes dulceacuícolas e incluso viven en sustratos húmedos en bosques tropicales. Como ocurre en otras especies estuarinas, los poliquetos neréididos pueden ser abundantes y relevantes como fuente de alimento para aves residentes o migratorias. Laeonereis culveri (Webster, 1879) es una especie común en estuarios, fue descrita de Nueva Jersey, E.U.A.; sus parápodos medianos y posteriores tienen lígulas notopodiales superiores generalmente más largas que las inferiores, y estas últimas son paralelas a las notacículas a lo largo del cuerpo. La distribución de L. culveri comprende desde Connecticut, E.U.A. hasta el litoral central de Argentina; esta amplia distribución podría deberse a la inclusión de otras especies como sinónimos menores, a pesar de las diferencias morfológicas entre ellas. Una de dichas especies, L. nota (Treadwell, 1941) fue descrita de Texas; sus parápodos medios y posteriores tienen lígulas notopodiales superiores de longitud similar a las inferiores, y estas últimas son oblicuas a las notacículas. Para clarificar las diferencias entre estas dos especies y determinar cuál de ellas se encuentra en el Caribe noroccidental, se estudiaron topotipos de ambas especies y se recolectaron ejemplares de la Bahía de Chetumal para comparar sus atributos morfológicos. Nuestros resultados indican que L. culveri y L. nota son especies diferentes y que la última se presenta en la Bahía de Chetumal. Con base en ejemplares maduros, L. culveri se restringe al norte del Golfo de México y Atlántico noroccidental y L. nota se reestablece con una distribución que se extiende desde Texas, en el Golfo de México a la Bahía de Chetumal, en el Caribe noroccidental. También se incluye una clave para la identificación de todas las especies de Laeonereis Hartman, 1945.

Polychaetes associated with decaying wood in Térraba mangrove, South Pacific, Costa Rica / Poliquetos asociados a madera en descomposición en el manglar de Térraba, Pacífico Sur, Costa Rica

Abstract The present study shows spatial patterns in the faunal assemblage of decaying wood and sediments, with emphasis on the polychaetes. The survey was executed across a salinity gradient in a tropical mangrove estuary of Costa Rica. To capture the organisms we analyzed decomposing logs found in the Térraba mangrove and sediment samples were taken with a corer in the sand bottom. Seven different phyla were found in the sediment samples. Of the 192 individuals found in the sediment samples, 18 were polychaetes belonging to nine families and 11 species. Analyses of decaying wood resulted in 2 564 individuals distributed in five phyla. Polychaetes accounted for 429 individuals belonging to eight families and 16 species. Although, polychaetes were more abundant in decaying wood, and their diversity was lower. The abundance of polychaetes in decaying wood was negatively correlated with the number of individuals of Mollusca, Hexapoda and Crustacea. A change in the composition of polychaetes in decaying wood was found along the salinity gradient of this estuarine zone. Dissimilarities in the composition of benthic fauna in decaying wood and sediments in the Térraba mangrove showed that biodiversity was increased by the microhabitats inside the mangrove forest. Finally, several genera or species of polychaetes are new records for Costa Rica and the Central American Pacific Coast. Rev. Biol. Trop. 63 (Suppl. 1): 61-74. Epub 2015 April 01.

Resumen Este artículo presenta datos sobre los taxones de fauna, con énfasis en poliquetos; hallados en madera en descomposición y sedimentos. El estudio se realizó a través de un gradiente de salinidad dentro de un manglar estuarino de Costa Rica. Se capturaron los organismos destruyendo los leños encontrados en el piso del manglar Térraba. También, se sacó muestras de sedimento con un cilindro plástico. Se encontraron siete filos diferentes en las muestras del sedimento. De los 192 individuos encontrados, 18 eran poliquetos, con nueve familias y 11 especies. Al inspeccionar las muestras de madera en descomposición se encontró 2 564 individuos, distribuidos en cinco filos. Los poliquetos sumaron 429 individuos en ocho familias y 16 especies. Aunque los poliquetos fueron más abundantes en la madera deteriorada, su diversidad fue mayor en las muestras de sedimento. La abundancia de poliquetos en los leños se asoció negativamente con el número de individuos de Mollusca, Hexapoda y Crustacea. Se encontró que el gradiente de salinidad explica en gran medida el cambio en la composición de fauna. La disimilitud en la composición de fauna bentónica hallada en la madera deteriorada y los sedimentos en el manglar de Térraba, indicó que la biodiversidad aumenta al interior del manglar, gracias a la diversidad de micro hábitats. Finalmente varios géneros o especies de poliquetos son nuevos registros para Costa Rica y en general para la Costa Pacífica Centroamericana.

Estructura de la comunidad y distribución vertical de la macrofauna de fondos blandos en isla Gorgona, Pacífico Colombiano / Community structure and vertical distribution of the soft bottom macrofauna on Isla Gorgona, Colombian Pacific

Soft bottoms are important in marine ecosystems but their ecology have been less studied in the tropics than in temperate areas. This article describes the temporal, spatial, and vertical distribution of the community structure of subtidal soft bottom macrofauna on Isla Gorgona, Colombian Pacific. Samples were collected in March and June 2011 by corers at 10m depth at five points around the island. Seventy-three species were recorded; polychaetes (55%) and crustaceans (30%) were the dominant groups in number of individuals. The community structure assessed by classification and ordination analysis did not change temporarily, but it shows differences between sampling points, due to the structure of the substrate. The highest abundances of macrofauna were recorded at points with dominance of fine particles (Farallones). However, another point with a similar substrate (Planchón) showed low abundance, apparently due to bioturbation exerted by the fish Heteroconger sp. The presence of Heteroconger sp. in El Planchón could also affect the vertical distribution of the macrofauna, where their relative abundance was homogeneous across the analyzed layers (1-2-3-4-5-10cm). In the other four sites, the abundance of the macrofauna was mainly limited to the first two centimeters of the sediment. Playa Blanca and Remanso showed substrates composed mainly of gravel, recording at the last sampling point the lowest richness, diversity and abundance. Rev. Biol. Trop. 62 (Suppl. 1): 169-188. Epub 2014 February 01.

Resumen Se evaluó la variación temporal, espacial y vertical de la estructura comunitaria de la macrofauna de fondos blandos submareales en isla Gorgona, Pacífico colombiano. Las muestras fueron colectadas en marzo y junio de 2011 mediante descorazonadores a 10m de profundidad en cinco puntos alrededor de la isla. Se registraron un total de 73 especies; poliquetos (55%) y crustáceos (30%) fueron los grupos dominantes en número de individuos. La estructura comunitaria evaluada mediante análisis de clasificación y ordenación, no varió temporalmente, pero si presentó diferencias entre puntos de muestreo, al parecer relacionada con la estructura del sedimento. Las mayores abundancias de la macrofauna se registraron en puntos con dominancia de partículas finas (Farallones), pero en otro punto con sustrato similar (Planchón), la abundancia fue baja, al parecer por la bioperturbación ejercida por el pez Heteroconger sp. La presencia de Heteroconger sp. en el Planchón posiblemente afectó la distribución vertical de la macrofauna, ya que en este último punto la abundancia relativa fue homogénea entre las capas analizadas (1-2-3-4-5-10cm). En los otros cuatro sitios, la abundancia de la macrofauna estuvo limitada principalmente a los primeros dos centímetros del sedimento. En Playa Blanca y Remanso el sustrato fue principalmente gravoso, registrándose en el último punto la menor riqueza, diversidad y abundancia.

Is nematode colonisation in the presence of Scolelepis in tropical sandy-beach sediment similar to the colonisation process in temperate sandy beaches? / A colonização dos sedimentos de praias tropicais por nematódeos na presença de Scolelepis é similar ao processo de colonização que ocorre em praias arenosas temperadas?

The role of a dominant macrobenthic polychaete, Scolelepis squamata, in the colonisation of defaunated tropical sediments by sandy-beach nematodes was investigated and compared with a previous colonisation experiment carried out on a temperate sandy beach. Experimental cylinders, equipped with lateral windows allowing infaunal colonisation, were filled with defaunated sediment containing two treatments, with and without S. squamata. These cylinders were inserted into microcosms containing sediment with indigenous meiofauna collected from the field. The treatments were incubated in the laboratory at ambient temperature and salinity for 7, 14 and 21 days. The nematode assemblages in both treatments did not differ in composition between treatments and from the natural assemblages, suggesting that all the species were equally able to colonise the experimental cores. The presence of the polychaete did not affect the development of the nematode community composition, in contrast to the results from a previous temperate-beach experiment. However, our results did not indicate whether the difference in results was caused by the different behaviour of the polychaete specimens, or by the different composition and response of the present nematode community.

Esse estudo avaliou a influência da espécie Scolelepis squamata (Polychaeta) no processo de colonização de sedimentos defaunados obtidos em uma praia arenosa tropical, além de comparar esses resultados com um estudo similar realizado em uma praia temperada. Sedimentos, previamente defaunados, foram colocados em amostradores com aberturas laterais, que permitiram a colonização da meiofauna. Foram definidos dois tratamentos, um com a presença e outro com a ausência da espécie S. squamata, além do controle. Os amostradores desses tratamentos foram alocados em unidades experimentais do tipo microcosmo, as quais continham sedimento com a meiofauna residente. Os tratamentos foram incubados em laboratório por 7, 14 e 21 dias, com condições controladas de temperatura e salinidade. Os nematódeos não apresentaram diferenças significativas em termos de composição entre os tratamentos e nem em relação ao controle, sugerindo que todas as espécies desse grupo foram, igualmente, capazes de colonizar as unidades experimentais. Esses resultados indicaram que a presença do poliqueto não afetou a estrutura da comunidade de nematódeos, o que representou um resultado contrário ao obtido para a praia temperada. No entanto, não se pode concluir se essas diferenças entre as praias estariam relacionadas ao comportamento diferencial de S. squamata ou pela presença de comunidades de nematódeos distintas nas praias.

Depth diversity profile of polychaete worms in Bahía Chatham, Isla del Coco National Park, Costa Rican Pacific / Perfil de diversidad en profundidad de gusanos poliquetos en Bahía Chatham, Parque Nacional Isla del Coco, Pacífico costarricense

The subtidal benthos of tropical islands has been poorly studied in the Eastern Tropical Pacific. Several studies have been published on taxonomic collections from oceanic islands in the region, but ecological features and community structure are practically unknown. In the present study, composition of the polychaete community along a depth gradient from the sand bottom of Bahía Chatham, Isla del Coco National Park, Costa Rica is analyzed. Fifty species of polychaetes belonging to 28 families were found. There is a peak in diversity, abundance and richness at 28-30m. The lowest values occurred at 50m depth with values increasing below this depth. The composition of species changed with depth with some species being found only at depths either less than or greater than 50m. This pattern can be explained in part by the location of the thermocline that occurred at around 50m depth.

El bentos submareal de las islas tropicales ha sido poco estudiado en el Pacífico Oriental. Varios estudios se han publicado sobre colecciones taxonómicas de las islas oceánicas de la región, pero las características ecológicas y la estructura de la comunidad son prácticamente desconocidas. En el presente estudio se muestra la composición de la fauna de anélidos poliquetos según un gradiente de profundidad en los fondos arenosos de la Bahía de Chatham, Parque Nacional Isla del Coco, Costa Rica. Cincuenta especies de poliquetos repartidas en 28 familias fueron encontradas. La comunidad muestra un pico en la diversidad, abundancia y riqueza a los 28-30m. Los valores fueron menores a 50m mientras que por debajo de esta profundidad se observó una tendencia hacia un aumento en la riqueza de la comunidad. La composición de las especies cambió de acuerdo a la profundidad y algunas especies sólo se encontraron por debajo o por arriba de los 50m. La ubicación de la termoclina en la profundidad de 50m podría explicar en parte el patrón encontrado.

Algunos poliquetos holoplanctónicos (Annelida: Polychaeta) del Parque Nacional Isla del Coco, Costa Rica / Some holoplanktonic polychaetes (Annelida: Polychaeta) from the Parque Nacional Isla del Coco, Costa Rica

The holoplanktonic polychaetes have not been surveyed in the oceanic waters adjacent to Isla del Coco. These pelagic forms are studied based on the analysis of zooplankton samples collected in the area. Samples were obtained both at night and daytime by standard plankton nets (0.2-0.5 mm meshes, 0.49 m mouth diameter) hauled horizontally and vertically off the oceanic island Isla del Coco, Costa Rica in the Eastern Tropical Pacific. Pelagic polychaetes were collected in one of the night samples and were taxonomically analyzed. The material obtained includes representatives of six species and five families: Alciopidae, Lopadorrhynchidae, Tomopteridae, Polynoidae, and Typhloscolecidae. Brief diagnoses, synonymies, comparative morphological comments, taxonomic illustrations, and data on the distribution of the species collected in the plankton of Isla del Coco are provided. The record of Drieschia pellucida Moore is the first of the species in the Eastern Tropical Pacific; our specimen shows some differences with respect to the original description. The rest of the species have been recorded previously in waters of the Eastern Tropical Pacific, but are the first records of this important protected area.

Los poliquetos holoplanctónicos no han sido estudiados en las aguas oceánicas adyacentes al Parque Isla del Coco. Se estudiaron estas formas pelágicas a partir del análisis de muestras de zooplancton recolectadas en esta área protegida. Las muestras fueron obtenidas mediante redes de plancton estándar (0.2-0.5mm de malla, 0.49m de diámetro de boca) en arrastres horizontales y verticales en la isla oceánica Isla del Coco, Costa Rica, en el Pacífico Tropical Oriental. Los poliquetos pelágicos de esta zona fueron analizados taxonómicamente. El material obtenido incluye representantes de seis especies y cinco familias: Alciopidae, Lopadorhynchidae, Tomopteridae, Polynoidae y Typhloscolecidae. Se presentan diagnosis breves, sino- nimias, análisis morfológicos comparativos, ilustraciones taxonómicas y la distribución conocida de las especies recolectadas en el plancton de Isla del Coco. El registro de Drieschia pellucida Moore es el primero en el Pacífico Tropical Oriental; nuestro espécimen muestra algunas diferencias respecto a la descripción original. El resto de las especies han sido encontradas previamente en aguas del Pacífico Tropical Oriental y en el Domo de Costa Rica, pero son los primeros registros para esta área protegida.

Annulata örstediana: publication dates, composition and annotated taxonomic list, with some comments on Hemipodus (Polychaeta: Glyceridae)

The collecting trips by Ørsted and Kröyer in Central and South America resulted in a series of papers by Grube, the Annulata örstediana which contained the proposal for seven genera and descriptions for 84 species. There are some problems dealing with the correct number of contributions, their publication dates, the correct citation for the authors for each species name and sometimes even for the type locality. In order to improve the current situation, we have consulted the original publications together with the corresponding collections. Our results indicate that there were only three parts in the series which were published in the journal, and repagination in reprints sometimes caused some further confusion. Additionally, we provided some review comments on the species current status and we added a short nomenclatural note on Hemipodus (Polychaeta: Glyceridae) trying to clarify the correct generic name and type species.

Los viajes de recolecta por Ørsted y Kröyer en Centroamérica y Sudamérica resultaron en una serie de notas por Grube, los Annulata örstediana que contienen la propuesta de siete géneros y 84 especies. Hay algunos problemas en relación con el número correcto de contribuciones, sus fechas de publicación, la citación correcta de los autores para cada nombre específico y a veces incluso para la localidad tipo. Para mejorar la situación, hemos consultado las publicaciones originales junto con las colecciones correspondientes. Nuestros resultados indican que hubo tres partes en la serie, que fueron publicadas en la revista y cuyas páginas fueron re-enumeradas para las separatas lo que a veces ocasionó confusiones adicionales. Además, brindamos algunos comentarios para revisar el estado de cada especie y agregamos una breve nota nomenclatural sobre Hemipodus (Polychaeta: Glyceridae) para aclarar el nombre correcto del género y la especie tipo.

Giant Eunicid Polychaetes (Annelida) in shallow tropical and temperate seas

Some species of Eunice might reach giant size, often being longer than 2m, and they are known from tropical and temperate seas. Despite their large size and recent internet notoriety, there remain some taxonomic problems in large-sized eunicids, especially since original descriptions were brief and type materials are often missing. As a mean to encourage the solution of this situation, we review the historical progress in the taxonomy of the group, including some comments on generic and specific delineation, and recommend some critical steps to solve the current confusion. These ideally would include collecting in type localities, evaluate ontogenetic morphological changes, and generate some molecular analysis to complement the morphological approach. Rev. Biol. Trop. 59 (4): 1463-1474. Epub 2011 December 01.

Algunas species de Eunice pueden alcanzar tamaño gigantesco, a menudo sobrepasan los 2m de largo, y se conocen de mares tropicales y templados. A pesar de su gran tamaño y de su reciente notoriedad en Internet, todavía hay problemas taxonómicos entre los eunícidos gigantes, especialmente dado que las descripciones originales fueron breves y a menudo se carece de materiales tipo. Para incentivar la solución del problema, revisamos el desarrollo histórico de la taxonomía del grupo y se incluyen algunos comentarios sobre la delineación de los géneros y de las especies y recomendamos algunos pasos críticos para alcanzar este fin. Idealmente, esto incluiría recolectar en las localidades tipo, evaluar cambios morfológicos durante la ontogenia y generar algunos análisis moleculares para complementar el enfoque morfológico.

Free-living marine polychaetes (Annelida) inhabiting hard-bottom substrates in Trinidad and Tobago, West Indies

As part of a larger comparative study, marine polychaete hard-bottom assemblages were surveyed using artificial substrate units (ASUs) deployed at four sites off the islands of Trinidad and Tobago. The polychaete fauna was represented by 19 families comprising 89 species. The syllid Exogone dispar was the most abundant polychaete followed closely by the serpulid Pseudovermilia occidentalis. At the family level, the polychaete fauna inhabiting the ASUs is similar to the fauna from other temperate and tropical locations. Omnivorous species were dominant (70 %), followed by filter feeders (20%). This survey provides first records of the hard-bottom polychaete fauna of Trinidad and Tobago and adds new information about the geographic range of some polychaete species. Rev. Biol. Trop. 58 (1): 147-157. Epub 2010 March 01.

Como parte de un estudio comparativo más amplio, ensamblajes marinos de poliquetos de fondos duros fueron contabilizados utilizando unidades de sustrato artificial ubicadas en cuatro sitios de las islas de Trinidad y Tobago. La fauna de poliquetos estuvo representada por 19 familias, integradas por 89 especies. Exogone dispar fue el poliqueto más abundante seguido cercanamente por Pseudovermilia occidentalis. A nivel de familia, la fauna de poliquetos que habitan las unidades de sustrato artificial es similar a la de otras localidades templadas y tropicales. Las omnívoras fueron las especies dominantes (70%), seguido por las filtradoras (20%). Este estudio proporciona los primeros registros de la fauna de poliquetos del fondo duro de Trinidad y Tobago, y añade nueva información sobre la distribución geográfica de algunas especies de poliquetos.

Polidiariose em ostras Crassostrea gigas cultivadas na praia da Ponta do Sambaqui, Florianópolis, Santa Catarina, Brasil / Polydiariosis in cultured oyster Crassostrea gigas from Ponta do Sambaqui, Florianópolis, Brasil

A infestação por poliquetas do gênero Polydora em ostras C. gigas de cultivo foi acompanhada por meio de coletas mensais enquanto os parâmetros físico-químicos da água do mar foram monitorados semanalmente. Foi determinada a área total ocupada pelas bolhas e tubos na superfície interna das valvas, observando os possíveis danos às principais características fisiológicas da ostra. Houve prevalência do anelídeo Polydora sp. (Polychaeta: Spionidae) em todos os meses amostrados, chegando a 100% no período de águas mais frias. As análises histológicas mostraram que os tecidos e órgãos estavam intactos, ocorrendo a formação de gametas. Nas ostras severamente infestadas, foi possível observar intensa fibrose na região do manto, mostrando reparo do tecido.

The infestation of polychaetes Polydora in oyster C. gigas within cultivation was accompanied by monthly samples whereas the physical and chemical parameters of seawater were monitored weekly. The total area occupied by bubbles and tubes in the inner surface of the valve was determined, indicating the possible damage to the main physiological characteristics of oysters. It was observed prevalence of annelid Polydora sp. (Polychaeta: Spionidae) in all samples each month, reaching 100% in the period of cooler waters. The histological analysis showed that the tissues and organs were intact, occurring the formation of gametes. In oysters severely infested, it was possible to observe intense fibrosis in the mantle, showing repair of the tissue.

Porcentaje del grado de infestación de polydora cf. websteri Hartman, 1943 (Polychaeta: spionidae) por clase de talla de Crassostrea rhizhophorae (Guilding, 1828) de la Laguna La Restinga (Isla de Margarita Venezuela) / Percentage of Infestation Level of Polydora cf. websteri Hartman, 1943 (Polychaeta: spionidae) by size class of Crassostrea rhizhophorae (Guilding, 1828) on La restinga Lagoon (Margarita Island Venezuela)

La infestación de moluscos bivalvos de interés comercial por parte de poliquetos espiónidos, especialmente aquellos pertenecientes a los géneros Polydora, Dipolydora y Carazziella, ha sido referida en numerosas ocasiones. Se realizó un estudio sobre la infestación de la ostra de mangle Crassostrea rhizophorae (Guilding, 1828) por el poliqueto espiónido Polydora cf. websteri Hartman, 1943 con el fin de determinar el nivel de infestación y la preferencia del poliqueto por una u otra valva. Se realizaron colectas mensuales (enero-julio) separando manualmente los bivalvos de las raíces de los mangles en la laguna de La Restinga. La presencia, ausencia e intensidad del ataque se registró en ambas valvas de cada individuo, estableciéndose niveles de infestación de acuerdo al número de galerías. El 64,57 por ciento de los bivalvos estaban infestados por el poliqueto. Se encontraron diferencias altamente significativas en la abundancia de galerías entre valvas (ts = 5,786, P < 0,001). No se observó correlación (Pearson) entre la talla y el número de galerías ni entre la biomasa y el número de galerías.

The infestation of mullusks bivalves with commercial importance by spionid polychaetes belonging, mainly, to genera Polydora, Dipolydora and Carazziella, has been recorded in many occasions. A study about of infestation of mangrove oyster Crassostrea rhizophorae (Guilding, 1828) by spionid polychaete Polydora cf. websteri Hartman, 1943 was made in order to determine the level of infestation and the polychaete worm preference by one or the other shell. Monthly samplings (January-July) were made. Bivalves were manually separated of mangroves roots from La Restinga lagoon. Presence or not and attack intensity was recorded in both valves of each specimen in order to establish infestation levels according to galleries spionid abundance. Almost 65 por ciento of bivalves showed infestation by the polychaete. Highly significative differences in the abundance of galleries between valves (ts = 5.786, P < 0.001)were found. Not Pearson correlation between the bivalve size and galleries number, nor biomass and galleries number was observed.

Antioxidant responses of Laeonereis acuta (Polychaeta) after exposure to hydrogen peroxide

The effects of H2O2 were evaluated in the estuarine worm Laeonereis acuta (Polychaeta, Nereididae) collected at the Patos Lagoon estuary (Southern Brazil) and maintained in the laboratory under controlled salinity (10 psu diluted seawater) and temperature (20°C). The worms were exposed to H2O2 (10 and 50 µM) for 4, 7, and 10 days and the following variables were determined: oxygen consumption, catalase (CAT) and glutathione peroxidase activity in both the supernatant and pellet fractions of whole body homogenates. The concentrations of non-protein sulfhydryl and lipid peroxides (LPO) were also measured. The oxygen consumption response was biphasic, decreasing after 4 days and increasing after 7 and 10 days of exposure to 50 µM H2O2 (P < 0.05). At the same H2O2 concentration, CAT activity was lower (P < 0.05) in the pellet fraction of worms exposed for 10 days compared to control. Non-protein sulfhydryl concentration and glutathione peroxidase activity were not affected by H2O2 exposure. After 10 days, LPO levels were higher (P < 0.05) in worms exposed to 50 µM H2O2 compared to control. The reduction in the antioxidant defense was paralleled by oxidative stress as indicated by higher LPO values (441 percent compared to control). The reduction of CAT activity in the pellet fraction may be related to protein oxidation. These results, taken together with previous findings, suggest that the worms were not able to cope with this H2O2 concentration.

Orbiniidae polychaetes (Polychaeta: Scolecida) from Coiba Island, eastern Pacific of Panama, with description of a new species

Santa Cruz and El Gambute, two mangrove systems with associated tidal flats, were sampled in Coiba National Park, Coiba Island, Pacific of Panama. At each site, two samplings were done at low, middle and high intertidal levels in February and November of 1997. A new orbiniid species were found: Orbinia oligopapillata n. sp. is characterized by having 15-16 thoracic chaetigers with four or five rows of uncini and up to three papilliform postchaetal processes on neuropodial lobes by the abdominal parapodia bearing flail-tipped neurochaetae, and by the presence on anterior-most abdominal chaetigers of interramal cirri and a low number of subpodial and stomach papillae. A specimen belonging to genus Leitoscoloplos Day, 1977 is described as "Leitoscoloplos sp.", characterized by the lateral pouches on its abdominal chaetigers, a unique case for the family because these brooding structures have only been previously cited in two species of Scoloplos. Naineris sp. is characterized by the number of its thoracic chaetigers, branchiae, uncini and bilobed abdominal neuropodia with protruding aciculae.

En el Parque Nacional de Coiba, costa pacífica de Panamá, hay manglares con playas asociadas. Estudiamos la fauna de dos poliquetos orbínidos de Santa Cruz y El Gambute. En cada playa se eligieron puntos de muestreo al nivel de marea baja, media y alta y cada uno se realizaron dos muestreos, en febrero y noviembre de 1997. Encontramos individuos no identificables con certeza y una especie nueva: Orbinia oligopapillata n. sp., la cual se caracteriza por tener 15-16 setígeros torácicos con cuatro o cinco filas de uncinos y hasta tres procesos postsetales papiliformes en los lóbulos neuropodiales, por los parápodos abdominales provistos de sedas en bayoneta y por la presencia en los setígeros abdominales anteriores de papilas estomacales en escaso número. Leitoscoloplos sp. se caracteriza por llevar bolsillos laterales en los setígeros abdominales, caracter único en el género y que en la familia solo ha sido citada en dos especies del género Scoloplos. Naineris sp. se caracteriza por el número de setígeros torácicos, sus branquias, sus uncinos y sus neuropodios abdominales, bilobulados y con la acícula sobresaliente.

Foraging and mobility in three species of Aciculata (Annelida: Polychaeta)

Aspects of feeding, such as food capture and ingestion, as well as mobility of the polychaetes Eurythoe complanata, Marphysa formosa and Diopatra aciculata, from São Sebastião Channel (São Sebastião, state of São Paulo) were observed in laboratory conditions. Eurythoe complanata, a carnivorous species, fed exclusively on pieces of fish with the aid of strong muscular retractable lips, and detected the presence of food by chemical stimuli. Diopatra aciculata, an omnivorous species, captured and ingested different kinds of food with the aid of its jaws, generating a flow of water through its tube by which it detects the presence of food and oxygenates its gills. Marphysa formosa also used its jaws to bite and lacerate food. These species showed greater or lesser degrees of intolerance to light.

Alguns aspectos da atividade alimentar, tais como a captura e ingestão de alimento, bem como a mobilidade dos poliquetas Eurythoe complanata, Marphysa formosa e Diopatra aciculata, procedentes do Canal de São Sebastião (São Sebastião, SP), foram observados em laboratório. Eurythoe complanata, carnívora, alimentou-se apenas de pedaços de peixe, utilizando os lábios retráteis fortemente musculares e detectando a presença do alimento através de estímulos químicos. Diopatra aciculata, onívora, capturou (com o auxílio das maxilas) e ingeriu os diferentes tipos de alimentos oferecidos, promovendo um fluxo de água para dentro do tubo, por meio do qual o animal detecta a presença de alimento e oxigena as brânquias. Marphysa formosa também utilizou as maxilas para morder ou rasgar o alimento. Durante as observações, foi constatado que estes poliquetas, em maior ou menor grau, apresentam intolerância à luminosidade.

Polychaeta (Annelida) associated with Thalassia testudinum in the northeastern coastal waters of Venezuela

Seasonal variations of polychaetes in a Thalassia testudinum bed were studied from June 2000 to April 2001 in Chacopata, northeastern Venezuela. Eight replicate samples were taken monthly with a 15 cm diameter core and the sediment was passed through a 0.5 mm mesh sieve. A total of 1,013 specimens, belonging to 35 species, was collected. The monthly density ranged from 387 ind/m2 (September) to 1,735 ind/m2 in May (x = 989+/-449 ind/m2). Species richness was lowest in August and September (8) and highest (25) in April (x = 18.00+/-5.29). The shoot density of Thalassia showed an average of 284+/-77.60 shoots/m2, with extreme values in February (164) and May (422). Species diversity ranged from 1.25 in August and 3.33 bits/ind in December (x = 2.47+/-0.64). Significant positive correlations were detected among the number of Thalassia shoots, polychaete abundance and species richness, as well as among species richness, polychaete abundance and species diversity. Species number and average density were found within the intervals of mean values reported in similar studies. The higher number of species and organisms obtained in March-April and June-July can be attributed to the recruitment correlated with the regional up-welling.