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Introduction: The tomopterids are holopelagic polychaetes widely distributed in all oceans, nevertheless they have been poorly studied despite their important implications in the trophic webs, as predators of various groups of zooplankton, including eggs and fish larvae. Objective: To describe the structure of the community of these pelagic worms in an upwelling area in the Central American Pacific. Methods: The zooplankton samples were obtained during the oceanographic campaign DOMO IV organized by the Universidad Nacional Autónoma de Mexico, in July-August, 1982. The polychaetes of the Tomopteridae family were sorted out and identified providing data on their specific composition, abundance and distribution. Results: Four species of the genus Tomopteris were determined, being T. elegans and T. planktonis dominant, T. nationalis constant and T. euchaeta rare. T. nationalis, T. elegans and T. euchaeta have tropical and subtropical affinies, while T. planktonis have been considered as cosmopolitan species. T. elegans had the higher relative abundance (62%) and T. euchaeta the lower (2.5%). Conclusion: Overall, T. elegans and T. planktonis showed a notable rise in the abundance related to upwelling in the thermal dome of Costa Rica. [ABSTRACT FROM AUTHOR]

Introduction: Several studies have demonstrated the effect of Cd on mortality and other physiological responses of some polychaete species. Objective: to evaluate the toxic effect of Cd on adults mortality of Polydora sp as a test species for ecotoxicological studies. Methods: The specimens were collected in the coastal wetland of Poza de la Arenilla, Callao, Peru. The organisms were acclimatized for two weeks with seawater and sediment and then, three days in seawater, with 30 ‰ of salinity and temperature between 20 to 22 °C. The organisms were exposed to the nominal concentrations 75, 11.25, 1.69, 0.25; 0.04 mg/L of Cd and a control. Three replicates of ten individuals per treatment were analyzed for 72 hours to register mortality. The Kruskal-Wallis and U-Man Whitney tests were applied to detect significant differences among treatments. Results: The adverse effect of Cd on mortality was much more evident in the treatments of 11.25 and 75 mg/L after the first 24 hours of exposure. The mean lethal concentration of Cd at 72h was 2.59 mg/L. Conclusions: the LC50 is in the same order of magnitude as other polychaete species. This is the first ecotoxicological study in Peru using polychaetes under laboratory conditions. It is suggested the use of Polydora sp as a test species in ecotoxicology experiments, using nominal sublethal concentrations of Cd not exceeding 1.6 mg/L. for the observation of several physiological responses. [ABSTRACT FROM AUTHOR]

Introduction: From a global point of view, polychaetes that inhabit in the pelagic community have been little studied, although they are an important link in the food chains of marine ecosystems. Objective: to analyze the local richness and density of polychaetes. Methods: Plankton samples were taken in 17 localities during May and December 2013, through surface trawls in a barge with an outboard motor. We used a net with 0.3 m mouth diameter, 1.30 m long and a 0.3 mm aperture mesh. From each collected sample, polychaetes were separated and determined at the lowest possible taxonomic level. Results: We collected a total of 1 873 individuals, with an important variation in relative density, since in May 7 952.0 ind/100m3 were recorded, while in December there were only 882.1 ind/100m3. The differences in the composition and density of the determined polychaetes, were analyzed, of which the highest proportion belongs to the larval forms of the benthic (meroplankton) populations, and the lowest proportion to holoplankton organisms. During the two periods of study were observed thirteen families, from which Sabellariidae, Spionidae, Chaetopteridae, Magelonidae, Iospilidae and Typhloscolecidae were common in both periods, while Aphroditidae, Syllidae, Phyllodocidae and Alciopidae were observed only in May, and Serpulidae, Sabellidae and Lopadorhynchidae were observed only in December. Conclusions: It is important to point out that the observed variations provide valuable information about the life cycles and the biogeographic aspects of the polychaetes in the study area. [ABSTRACT FROM AUTHOR]

The marine-estuarine polychaete Capitella capitata is an endobenthic species which is considered as a cosmopolitan organism. The laboratory culture of this species-complex allows its use as a test species in toxicity bioassays and reproduction studies. Objective: It is pretended to observe mortality under two temperature and salinity ranges as optimal conditions to culture Capitella sp. in the laboratory. Metodology: Polychaetes were collected in Callao Province, Peru, during November 2016 and January 2017. A bioassay was carried out to observe mortality under different temperature and salinity ranges using two treatments: treatment 1, with polychaetes collected during January 2017, which were subjected to conditions similar to the collection site (temperature: 20-22° C, salinity: 30-32 psu); treatment 2, with the organisms collected during November 2016, with temperature (24-26 °C) and salinity (32 a 34 ups) selected according to bibliographic data. Results: The increase of temperature and time significantly influenced polychaete mortality of the two treatments (Spearman correlation), while salinity and dissolved oxygen did not show correlation with mortality. Significant effect of time was observed on mortality, with more deaths from the second half of the experiment. Organisms from treatment 1, with environmental conditions similar to those of their habitat survived more than worms from treatment 2. These results were also observed in the porcentual varibility of the variation coefficient among days in each treatment. The cumulative mortality curve did not show differences between treatments. Conclusion: The optimal ranges to culture Capitella sp. in the laboratory are those from their habitat. In addition to temperature and time, other posible causes of the observed mortality can be worms age, health or maturity, and probably the bad quality of the water used during the bioassay. [ABSTRACT FROM AUTHOR]

The article focuses on the Lineus longissimus, also known as the "bootlace worm" or "gusano cordón de bota," which is possibly the longest animal on Earth. It discusses its characteristics, distribution in shallow waters, and its presence in the northern regions of Europe, including the North Sea, the Baltic Sea, and coastal areas of the British Isles, France, Asturias, Galicia, and the Cíes Islands. It article also delves into its anatomy, respiratory system, reproduction, and feeding habits.

Four hundred-thirty six polychaetes collected in soft bottoms from the Gulf of Venezuela were examined. Samples were taken from ninety stations, between 2008 and 2012. Thirhteen species were identified, belonging to four families from Eunicida: Eunicidae (6 spp.), Onuphidae (5 spp.), Lumbrineridae (1 sp.) and Oenonidae (1 sp.). Seven of these species are new records for Venezuela. These results increase the knowledge about marine biodiversity from the continental shelf in Venezuela and the southern Caribbean Sea. [ABSTRACT FROM AUTHOR]

In this study, fifteen species of benthic polychaetes associated with soft bottoms of the Gulf of Venezuela are taxonomically analyzed. The material was collected in ninety stations between 2009-2012. A total of 421 specimens were examined, among which 13 species of wandering polychaetes belonging to eight families were identified. Among the species identified Paranaitis polynoides, Phyllodocidae, and Aglauphamus verrilli, Nephtyidae, constitute new records for Venezuela. These results increase knowledge about marine biodiversity in the Venezuelan continental shelf. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Científica Juyyaaania is the property of Universidad Autonoma Indigena de Mexico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report the presence of nocturnal pelagic aggregations of adult individuals of the polychaete Platynereis australis (heteronereids) associated with Macrocystis pyrifera kelp beds in several locations (7) along Fueguian and Magellan channels, Chile (53º-55ºS, 67º-73ºW), in 2006 and 2007. Adult specimens showed morphological changes in 2/3 of the body, with modified parapodia and large coalescent black eyes. Pre-natatory region consists of 19 to 22 segments, while the epitoke region comprises from 60 to 90 segments. Specimens were sexually mature and mean egg size between 135 and 155 µm in diameter, having a similar size along the entire body, indicating a simultaneous development in the coelomic cavity. Pelagic swarms were observed in all sites in spring. Observations made in autumn reported the presence of heteronereids in tubes attached to Macrocystis fronds. This may constitute the existence of an intermediate phase between the benthic and pelagic phase. However, further studies are required to clarify this behavior. We discuss the close association between Platynereis and forests of M. pyrifera at different stages of their life cycle. [ABSTRACT FROM AUTHOR]

One-hundred fifty-six specimens of polychaetous belonging to the family Orbiniidae were taxonomically analyzed, worms were collected in 21 localities of the coasts of Venezuela, it with the purpose of contributing to the knowledge of polychaetes biodiversity from the region. It was used a PVC corer (0,018 m²) and van Veen dredge (0,027 m³). Ten species were identified: Leitoscoloplos robustus, Scoloplos (Leodamas) rubra, Scoloplos (Leodamas) texana, Scoloplos (Scoloplos) cf. capensis, Orbinia riserii, Orbinia americana, Orbinia sp., Naineris setosa, Califia cf. calida, and Protoaricia cf. pigmentata, all these are new records for Venezuela and extending their geographic distribution in the Grand Caribbean. [ABSTRACT FROM AUTHOR]

Polychaetes have a high diversity and abundance in all oceans. They have important role as biological indicators of marine water quality. In Colombia, they have been studied for about 30 years, in which 43 families, 138 genera and 253 species have been identified, from central and north Colombian Caribbean coasts. The aim of this research was the taxonomic analysis of material belonging to the family Terebellidae, deposited in the Invemar Invertebrate Collection. Eight genera and 11 species of terebellids were previously identified; nevertheless, after this research, these numbers were increased to ten genera, and 17 species. The scarce information about polychaetes available in Colombia, and the lack of stardardized, updated taxonomic world revisions, not only for terebellids but also for the entire group of polychaetes, led to many incorrect species identifications, and the belief that some species are cosmopolitan in distribution. Anincrease in funding of basic taxonomic research will permit better estimates of the true polychaete diversity found in Colombian seas. [ABSTRACT FROM AUTHOR]

Specimens belonging to eight species of Amphinomidae and one of Euphosinidae collected in different localities of the East coast of Venezuela were identified: Amphinome rostrata, Chloeia viridis, Chloenopsis atlantica, Eurythoë complanata, Hermodice carunculata, Linopherus canariensis, L. pauci- branchiata, Notopygos crinita (Amphinomidae) and Euphrosine triloba (Euphrosinidae). Except for Eurythoë, Hermodice and Notopygos, the remain genera or species constitute new records from Venezuelan coast. [ABSTRACT FROM AUTHOR]

Copyright of Nova Acta Científica Compostelana is the property of Universidad de Santiago de Compostela, Servicio de Publicaciones and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nova Acta Científica Compostelana is the property of Universidad de Santiago de Compostela, Servicio de Publicaciones and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study evaluates the effect of weekly immersion baths in fresh water and a 0.2% solution of calcium hydroxide (lime) on the intensity of fouling polychaete worms in Crassostrea gigas oysters. Initially, 135 juvenile oysters (with an average length of 2.75 ± 0.25 cm and a mean wet weight of 4.33 ± 0.96 g) were randomly assigned to three groups with three replicates each. Two groups were treated for 10 minutes with lime and fresh water, respectively, and a third group remained as control. Fouling polychaete intensity and the bivalve length and weight were obtained every 15 days. Every week oyster survival was registered for each treatment and water parameters were measured at the culture site. Significant differences (P<0.05) in worm intensity were found between the two bath treatments and the control. The lime treatment showed the lowest intensity (number of mud tubes/oyster) in all the sampling days, with no increase in intensity during the last experimental month. There were no significant differences (P>0.05) in, final survival, final length, final weight and final condition index of the oysters among treatments after 112 days of study. [ABSTRACT FROM AUTHOR]