Charybdis hellerii is one of several poorly known non-indigenous crabs in the Caribbean. In this study we report on the reproductive dynamic of a shallow subtidal population that invaded Isla Margarita, Venezuela, south-eastern Caribbean Sea > 15 years ago and has persisted in the region up to date. Male and female crabs, both large and small, were found year-round at the study site. The size–frequency distribution indicated a lifespan of 2–3 years. Charybdis hellerii reproduces continuously but with very low intensity during the year. Small individuals (<25 mm carapace length) were uncommon and intermittently found during the study period. Sex-ratio varied between 0.1 and 0.65 (mean ± SD = of 0.46 ± 0.14) and did not differ significantly from 1:1 ratio during most of the year. The size of the smallest brooding female was 36.81 mm carapace width (CW). Behavioural size at first maturity (movable abdomen) in males and females was estimated to be 22.39 mm CW (confidence limits: 18.35–24.72) and 37.43 mm CW (35.55–39.09), respectively. Reproductive output, estimated as the ratio of embryo to female body dry mass, varied between 0.052 and 0.084 (0.07 ± 0.008). Also, reproductive output was size-dependent with large females allocating proportionally less resources to egg production than small females. The reproductive schedule here reported for C. hellerii disagrees with the generalized idea of exotic populations ‘thriving’ in an environment free of natural enemies (e.g. predators, competitors and diseases).

Recent exploration of the New England and Corner Seamounts revealed four new species of Chrysogorgia, described here using a combination of molecular and morphological data. These four species are characterized by a sinistral spiral, a character that, with one known exception, has only been reported for Pacific species. In addition, two species have a sclerite composition typical of the Pacific (‘squamosae typicae’). This faunal connection between the Atlantic and the Pacific is confirmed by analysis of the mitochondrial msh1 gene. The exceptional preservation of specimens collected with remotely operated vehicles allows us to discuss the effect of growth on some morphological characters.

There have been many efforts to appraise the extent to which artificial reefs affect the surrounding community, but few studies addressed whether benthic assemblages change with distance from the reef. We experimentally assessed the relationship between infauna abundance and richness with increased distance (0, 5, 25, 50, 100 and 300 m) from reefballs deployed on a flat and homogeneous bottom, 9-m deep, on the north coast of Rio de Janeiro, south-eastern Brazil. Benthic taxon richness and abundance varied significantly between surveys with higher values in February 2007. Both numerical indicators changed similarly with distance, but more noticeably between 300 m and the other distance treatments where abundance was highest. A non-metric multidimensional scaling ordination revealed that macrobenthic assemblages were very heterogeneous with significant differences between surveys but not among sampling distances. A canonical correspondence analysis including species, distances and sediment variables showed that the distances 5, 25 and 100 m were related to organic matter and mud (fine sediment), while 0 and 300 m distances were more related to the non-organic variables, such as the percentage of gravel, sand and calcium carbonate. Spatial variations in the parameters of the sediment alone did not explain the distribution of the associated infauna, given the similarity of the community at different distances. It is suggested that the influence of artificial reefs is quickly dissipated due to strong bottom sea currents, indicating a reduced impact or influence of these reefs on the surrounding infauna.

The feeding ecology of striped dolphin, Stenella coeruleoalba, in the north-western Mediterranean Sea was studied using stable isotope analyses. Carbon and nitrogen stable isotope ratios were measured in skin and muscle tissues of stranded and by-caught dolphins from six geographical areas in the Mediterranean Sea and Atlantic Ocean. Variation in δ15N in relation to dolphin size is attributed to changes in diet. Nursing calves have a higher trophic level than weaned animals and their δ15N values decrease progressively until weaning, estimated to be at a body length of around 155 cm. δ15N values then increased for larger individuals which suggests changes in diet for mature dolphins. Geographical differences in diet were apparent between the Atlantic and the Mediterranean, although no clear differences were apparent between the five Mediterranean areas. Comparisons of the nitrogen isotope ratios of skin and muscle highlighted a higher fractionation in skin compared to the muscle tissue. Values of δ13C also increased with body length although it appears that this is not only driven by trophic level enrichment. δ13C increases before weaning and the difference in trophic level between newly-weaned and mature dolphins was twice as high for carbon as for nitrogen. Ontogenetic changes in carbon isotope composition may therefore be driven by feeding on deep water prey and dolphin movements outside the coastal feeding grounds. Indeed, seasonal variations in δ13C are suspected to be driven by migration within the Mediterranean basin.

The northern Galician rias provide important economic and social services from fisheries, shellfish harvesting and recreational activities. Consequently, these rias have been included in the Nature 2000 Network as a Special Conservation Zone. The aims of this study were to describe the meiofauna spatial structure in terms of diversity and abundance of major taxa, as well as its relationship with the environmental characteristics in the Ria de Foz nature reserve. For this aim, environmental gradients and distribution patterns of intertidal meiobenthic communities at the Ria de Foz nature reserve were studied using multivariate methods. Ria de Foz showed to be a complex transitional habitat with significant changes in its environment along the estuarine gradient. An abundant and rich meiofauna community was reported at Ria de Foz. A total of 21 higher taxa of meiofauna were found. The most common taxa were nematodes, copepods, ostracods and turbellarians. Three clear different meiobenthic communities were defined. These three communities showed a clear spatial distribution pattern along the estuarine gradient. Moreover, a high degree of similarity between distribution patterns of meiobenthic communities and previously studied macrobenthic communities was found. Regarding the role of environmental factors shaping meiobenthic community distribution patterns distance to the river mouth was the environmental variable that best explained meiobenthic community structure and distribution. Therefore, changes on hydrodynamics that affect environmental factors related to the estuarine gradient will change the distribution pattern and diversity of benthic communities. This work provides the first information about meiobenthos diversity and structure in the Ria de Foz nature reserve and should be useful for future management and conservation plans on this and other similar protected areas.

To examine the specific features of trench communities, spatial changes in the assemblages of harpacticoids were investigated at the family level around the Ryukyu Trench (the Ryukyu region) and Kuril Trench (the Kuril region). In the Ryukyu region, there were high average dissimilarities in the harpacticoid assemblages among the trench, trench slope and abyssal plain, indicating that the assemblage structures differ substantially between these topographic settings at the family level. Conversely, in the Kuril region, the average dissimilarities in harpacticoid assemblages between the trench and the trench slope and between the trench and the abyssal plain were lower than that between the slope and the abyssal plain. This result suggests that the hadal assemblage is a transition zone between the slope and the abyssal plain in this region. In addition, the analyses indicate that the composition of harpacticoid assemblages is influenced by the quantity of organic matter in the Ryukyu region, while sediment properties play a key role in the Kuril region. Comparisons of the assemblages between the two regions, however, revealed that the average dissimilarities between the trenches and between the abyssal plains were higher than that between the adjacent slopes. This result suggests that interchange among regions is difficult for deep-sea benthic animals, including harpacticoid copepods, likely due to the presence of physical barriers around trenches.

Pacifigorgia marviva, a new shallow-water species of the family Gorgoniidae, was found in Coiba National Park, Pacific Panama at 35–40 m depth. It is characterized by having white to cream, small, erect colonies composed of 1–4 fronds, stems short or absent network irregular and open without fan midribs, and polyp mounds slightly raised and sparsely distributed. All sclerites are colourless. Coenenchymal sclerites mostly composed of long spindles reaching up to 0.25 mm in length, and long and thin anthocodial rods, up to 0.16 mm in length. Morphological characters are analysed and illustrated. Scanning electron microscopy was used for sclerite study. The new species is herein described and compared with other similar species reported from the eastern Pacific. Pacifigoria marviva increases the number of Pacifigorgia species to 35; 20 in Panama representing 57% of the genus in the eastern Pacific, followed by Costa Rica and Ecuador with 14 and 10 species, respectively.

Deep-water corals are known to provide essential habitat for fish and invertebrates along the continental slope in different areas of the world, offering prey to coral predators, protection or attachment substrate to other suspension feeders. In the Mediterranean Sea the coral Isidella elongata (Esper, 1788) characterizes a facies of bathyal compact mud substrates between 500 and 1200 m depth. Based on 4 experimental surveys carried out between 1985 and 2008, we obtained quantitative data on the fauna associated with live coral stands. We show that species richness of invertebrates and crustaceans, as well as abundance and biomass of crustaceans, is higher in areas with large stands of the coral. Some commercial fishery species are also more abundant or reach larger sizes in areas with high density of the coral, particularly the red shrimps Aristeus antennatus (Risso, 1816) and Plesionika martia (A. Milne Edwards, 1883). Trawling over I. elongata facies causes direct impacts on the biological assemblages by removing the habitat-forming corals, decreasing invertebrate species diversity and negatively affecting fisheries production in the long term.

The contribution of non-loricate ciliate assemblage to the ecological pattern of a ciliated protozoan community was studied based on a 1-year (June 2007–May 2008) dataset collected from Jiaozhou Bay, northern China. Samples were collected biweekly from five sampling sites. Results showed that: (1) the non-loricate ciliate assemblages were the primary components and significantly correlated with the total ciliate communities in terms of species number, abundance and biomass; (2) the ecological pattern of non-loricate ciliate assemblages was significantly related to that of both total ciliate communities and variations in environmental variables; and (3) spatio-temporal variations in biodiversity (richness, diversity and evenness of species) indices of non-loricate ciliate assemblages were significantly correlated with those of total ciliate communities and the environmental conditions, especially nutrients nitrate nitrogen, nitrite nitrogen and soluble reactive phosphorous. These results suggest that the non-loricate ciliates are a primary contributor to the ecological pattern of total ciliate communities and might be used as a potential bioindicator for bioassessment in marine ecosystems.

Distributions of deep-sea fish, benthic invertebrates and the effects of deep-sea bottom trawling were studied based on data collected in 2005 from a joint collaboration survey undertaken between the Spanish Institute of Oceanography and a deep-sea trawler on the Hatton Bank (north-east Atlantic). A total of 163 valid bottom trawl hauls (600–1600 m) were analysed. The main trawlable grounds were located on the sedimentary seabed of the western flank of the bank (Hatton Drift). Grenadiers and smoothheads were predominant in the trawl catches (67% and 11.8% by weight respectively). Both species were abundant along the western flank. Deep-water sharks accounted for 7.4% of weight, and were abundant along the south-eastern slopes. Chimerids, lotids, morids and other deep-sea species were also taken as by-catch. Grenadiers and deep-water sharks dominated the discards. By-catches of cold-water corals were generally associated with the rocky outcrop and were more abundant at the top of the bank. Abundant by-catches of large sponges, characteristic of sponge-dominated biotopes, were taken from the eastern flank.

The annotated literature of Blastomussa loyae Head, 1978, together with the comparison of descriptions and figures by various authors, new observations in the field, collected and figured samples from the northern Red Sea provide the basis to regard the species as valid and distinct from B. merleti (Wells, 1961).

This paper focuses on Antomicron, Leptolaimus and Procamacolaimus, three genera inhabiting coastal water systems of the Patagonian, Chubut and Santa Cruz provinces of Argentina, providing a review of their taxonomy for a new identification key. One new species belonging to the genus Antomicron and one new species belonging to the genus Leptolaimus of the family Leptolaimidae are described from Puerto San Julián, Santa Cruz province: Antomicron alveolatum sp. nov. has 35 alveoli and three precloacal supplements and Leptolaimus gabinoi sp. nov. is characterized by the structure and number of precloacal supplements (three) with hamate distal end with two hooks. Another species belonging to the genus Procamacolaimus of the family Camacolaimidae is described and recorded from Puerto Madryn, Chubut province of Argentina: Procamacolaimus dorylaimus.

This paper aims to study the morphological and gonadal maturity of the swimming crab Callinectes danae in the Santa Cruz Channel, Brazil. Crabs of both sexes were measured at carapace width (CW), carapace length (CL), abdomen width (AW), length of the right chelipod (LRC), and dissected to visualize the gonads. The gonadal maturity was estimated based on the frequency of mature individuals per class of CW, and the determination of morphological maturity was based on the relationship between the structures LRC versus CW for males and AW versus CW for females. The sizes that 50% of females reached gonadal and morphological maturity were 62.5 and 59.5 mm CW respectively. In turn, the sizes that 50% of males reached gonadal and morphological maturity were 74.5 and 70.5 mm CW respectively. In the analysis of dispersion of points in relation to AW versus CW, it could be observed that juvenile females showed positive allometry and adult females showed negative allometry, indicating a higher growth rate during the juvenile phase, related to the need of expanding the abdomen for egg incubation at the adult phase. In the relation LRC versus CW, it was observed that both juvenile and adult males showed positive allometry, but changes in the degree of allometry were evident between the two phases. The exceeding growth of the chelipod of males may be related to the reproductive process, including courtship and agonistic interactions with other males.

This study constitutes a first contribution to the knowledge of the ecology of the decapod crustaceans in waters off Guinea-Bissau. Samples were collected during a survey undertaken between October and November 2008. A total of 122 species of decapod crustaceans were identified. Results showed an increase of decapod biomass and abundance with depth, reaching maxima values in the 200–500 m depth stratum but decreasing at depths over 500 m. Average diversity by strata increased with depth, with maximum over the deep slope. Seven main assemblages were identified: five primarily associated with depth—coastal shelf (<60 m), shelf (60–200 m), upper slope (200–300 m), middle slope (300–500 m), deep slope (500–1000 m)—and two other northern shelf assemblages affected by sediment type—coastal shelf-north (<50 m) and shelf-north (50–100 m). Species of each assemblage are typified. This study provides new information about composition, distribution, abundance and assemblage structure of decapod crustaceans in Guinea-Bissau that may be useful for future assessment of the effect of trawling pressure in the area.

In this study we describe community parameters such as densities, biomasses, species composition, feeding modes and normalized biomass size-spectra (NBSS) of macrobenthic invertebrate communities from three stations located in the Baker Fjord obtained on four seasonal campaigns in 2008 and 2009. The macrobenthic communities were dominated by small-bodied polychaetes (Paraonidae, Capitellidae and Cirratulidae) characterized by continuous year-round breeding, short life-spans, and fast turnover rates, which in turn regulated the standing stock in the communities. Principal component analysis and multiple-regression analysis demonstrate the distribution of macrobenthic communities in the study area to be mainly controlled by few local environmental conditions. Macrofaunal densities, diversity and feeding modes were significantly correlated with the total organic carbon (TOC; R2 = 0.74; P < 0.001) and chlorophyll-a (Chl-a; R2 = 0.55; P < 0.05) content in the sediments. This study also suggests that feeding modes and NBSS can be used to detect and follow possible changes caused by natural perturbations such as glacial lake outburst floods or anthropogenic stressors associated with ecological impacts generated by the construction and operation of hydroelectric power stations in the Baker River.

A dual stable isotope approach (δ13C and δ15N) was used to investigate inter- and intra-specific variations in feeding ecology and habitat use of 7 delphinids from coastal/estuarine, continental shelf and offshore marine environments from southern Brazil: Tursiops sp., Orcinus orca, Stenella frontalis, Steno bredanensis, Delphinus delphis, Pseudorca crassidens and Lagenodelphis hosei. Teeth from 50 specimens acquired from stranded animals were analysed in this study. Tursiops sp. and O. orca are the most coastal species, and had the highest δ13C values followed by the continental shelf species S. frontalis, S. bredanensis and D. delphis. Lagenodelphis hosei showed the lowest δ13C value, demonstrating its typical offshore habitat. One group of P. crassidens had the lowest δ15N values, indicating their low trophic level feeding habit while two specimens of the same species showed the highest mean nitrogen isotope value. This first study on stable isotope values of delphinids from southern Brazil provides substantial new information about the trophic ecology, habitat use and feeding environments of these animals.

Three new species of free-living marine nematodes Micoletzkyia longispicula sp. nov., Micoletzkyia filicaudata sp. nov. and Micoletzkyia nanhaiensis sp. nov. from the Yellow Sea and the South China Sea are described. Micoletzkyia longispicula sp. nov. is characterized by spicules elongated and straight, 7 a.b.d. long, pear-shaped proximally and pointed distally; gubernaculum conical, without apophysis, and tubular supplement headlike proximally. Micoletzkyia filicaudata sp. nov. is characterized by slender body with relatively long filiform tail (8.1 a.b.d.), spicules elongated and straight (4.4 a.b.d.), cephalate proximally and pointed distally, gubernaculum tubular, with dorsal apophysis. Micoletzkyia nanhaiensis sp. nov. is characterized by spicules slender and curved, 2.5 a.b.d. long, cephalous proximally and chapiter-shaped distally, and gubernaculum with relatively long dorsal apophysis. A key for all known species of Micoletzkyia is proposed.

Light is one of the most important abiotic factors influencing the (skeletal) growth of scleractinian corals. Light stimulates coral growth by the process of light-enhanced calcification, which is mediated by zooxanthellar photosynthesis. However, the quantity of light that is available for daily coral growth is not only determined by light intensity (i.e. irradiance), but also by photoperiod (i.e. the light duration time). Understanding and optimizing conditions for coral growth is essential for sustainable coral aquaculture. Therefore, in this study, the question was explored whether more light (i.e. more photons), presented either as irradiance or as light duration, would result in more growth. A series of nine genetically identical coral colonies of Galaxea fascicularis L. were cultured for a period of 18 weeks at different light duration times (8 hours 150 μE m−2 s−1:16 hours dark, 12 hours 150 μE m−2 s−1:12 hours dark, 16 hours 150 μE m−2 s−1:8 hours dark, 24 hours 150 μE m−2 s−1:0 hours dark) and different irradiance levels (8 hours 150 μE m−2 s−1:16 hours dark, 8 hours 225 μE m−2 s−1:16 hours dark and 8 hours 300 μE m−2 s−1:16 hours dark). Growth was determined every two weeks by measuring buoyant weight. Temperature, salinity and feeding levels were kept constant during the experiment. To detect possible acclimation of the corals to an increased light duration, rates of net photosynthesis and dark respiration were measured, hereby comparing coral colonies grown under an 8:16 hours light (150 μE m−2 s−1):dark cycle with corals grown under a 16:8 hours light (150 μE m−2 s−1):dark cycle. No increase in growth was detected with either increasing photoperiod or irradiance. Continuous lighting (24 hours 150 μE m−2 s−1:0 hours dark) resulted in immediate bleaching and the corals died after 14 weeks. Hourly photosynthetic rates were significantly reduced in the 16 hour light treatment compared to the 8 hour light treatment. As a result, daily net photosynthetic rates were not significantly different, which may explain the observed specific growth rates. Acclimation to photoperiod duration appeared neither to be mediated by changes in chlorophyll-a concentration nor zooxanthellae density. Based on the results of this study, we can conclude that the enhancing effect of light on coral growth is not only a matter of photons. Obviously, the availability of light was not limiting growth in these experiments and was probably in excess (i.e. stressful amounts). Other factors are discussed that play a role in determining growth rates and might explain our results.

The invasion of marine species is a threat to local and global biodiversity and can have many ecological, economic and social impacts. The bivalve Isognomon bicolor has invaded the rocky shores of Brazil and spread along the coast, occurring from Rio Grande do Norte to the Santa Catarina State. The present study evaluated the distribution of I. bicolor on different rocky shores of Arvoredo Island (Santa Catarina State) and its relationship with other taxa. A high density of I. bicolor was found on the exposed shore, which was associated with the occurrence of articulated calcareous macroalgae. In addition, I. bicolor was also found in empty shells of the barnacles Tetraclita stalactifera and Megabalanus spp. The physical structure of these habitats probably plays an important role in the success of I. bicolor invasion. For these reasons, I. bicolor evidences an alteration on the benthic community of the rocky shores and its potential consequences become a threat to local species.

Macrobenthic assemblages were examined in three fish estuarine nurseries and related to environmental variables, as well as fish and macrocrustaceans, in order to assess and compare the potential foraging ground value of these systems. Macrobenthos was sampled in spring 2007 in the Canche, Authie and Somme estuaries (eastern English Channel, France). A total of 17, 28 and 23 macrobenthic taxa, with a clear dominance of amphipods (mainly Bathyporeia sarsi), polychaetes and bivalves, were recorded in the three estuaries respectively. Although predators (fish and macrocrustaceans) were abundant, relatively high densities of macrobenthos were observed: 876.2 ± 389.1, 595.4 ± 197.2 and 854.3 ± 281.2 ind. m-2 in the Canche, Authie and Somme, respectively. No significant difference in species richness, Shannon–Wiener diversity and density (total and dominant groups) of macrobenthos was observed between the three estuaries. Although the analysis of similarity and similarity percentages analyses indicated that macrobenthic assemblage was variable between Authie and Somme, results showed that macrobenthos resource was relatively high and similar in the three estuaries. Taking into account these considerations, the present study indicated a similar relative importance of the Canche, Authie and Somme estuaries as foraging grounds for fish and macrocrustaceans during spring. Multivariate analysis showed that macrobenthic assemblages were mainly driven by salinity and sediment characteristics in the Canche and Authie estuaries while in the Somme estuary sediment characteristics were the most influencing parameters.