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Despite its ubiquity and its role as an ecosystem engineer on temperate intertidal mudflats, little is known of the spatial ecology of the lugworm Arenicola marina. We estimated lugworm densities and analyzed the spatial distribution of A. marina on a French Atlantic mudflat subjected to long-term clam digging activities, and compared these to a nearby pristine reference mudflat, using a combination of geostatistical techniques: point-pattern analysis, autocorrelation, and wavelet analysis. Lugworm densities were an order of magnitude greater at the reference site. Although A. marina showed an aggregative spatial distribution at both sites, the characteristics and intensity of aggregation differed markedly between sites. The reference site showed an inhibition process (regular distribution) at distances

Human exploitation of bivalve populations has changed intertidal landscapesworldwide.Many bivalves are ecosystemengineers thatmodify the physical environment, affecting the conditions for their survival. Herewe argue that lack of recovery of overexploited intertidal bivalve beds may be partly caused by the loss of important biological feedbacks from depleted populations. In a large-scale experiment we investigated engineering effects of cockles (Cerastoderma edule L.) and lugworms (Arenicola marina L.) on juvenile cockles by adding high densities of either species to 5 × 5 mplots in areas with different hydrodynamic and sediment conditions in the intertidal flats of the Wadden Sea. We hypothesized that cockles would facilitate the new generations by increasing sediment stability, while lugworms would have negative effects on juvenile cockles through sediment disturbance. We found that in sandy areas with high wave and current energy cockles enhanced sediment accumulationand promoted local densities of young cockles, while lugworms did not have any effect on juvenile cockles. In muddy sites sheltered from the tidal currents by mussel reefs (Mytilus edulis L.), juvenile cockle densities weregenerally high, demonstrating the general importance of biological engineering for recruitment processes in the intertidal. We suggest that the acknowledgement of positive feedbacks between bivalves and sediment stabilityis essential to achieve long-term restoration goals in coastal ecosystems. © 2014 Elsevier

Morganella arenicola Alfredo & Baseia sp. nov. from Brazilian forests is proposed as a new species based on its morphological features. A comparative analysis of several collections of Morganella compacta (G.Cunn.) Kreisel & Dring, including the holotype, is added. Detailed description, taxonomical remarks, and illustrations with photographs and scanning electron microscopy of the basidiospores are given.

SummaryInadequate products, waste management, and policy are struggling to prevent plastic waste from infiltrating ecosystems [1, 2]. Disintegration into smaller pieces means that the abundance of micrometer-sized plastic (microplastic) in habitats has increased [3] and outnumbers larger debris [2, 4]. When ingested by animals, plastic provides a feasible pathway to transfer attached pollutants and additive chemicals into their tissues [5–15]. Despite positive correlations between concentrations of ingested plastic and pollutants in tissues of animals, few, if any, controlled experiments have examined whether ingested plastic transfers pollutants and additives to animals. We exposed lugworms (Arenicola marina) to sand with 5% microplastic that was presorbed with pollutants (nonylphenol and phenanthrene) and additive chemicals (Triclosan and PBDE-47). Microplastic transferred pollutants and additive chemicals into gut tissues of lugworms, causing some biological effects, although clean sand transferred larger concentrations of pollutants into their tissues. Uptake of nonylphenol from PVC or sand reduced the ability of coelomocytes to remove pathogenic bacteria by >60%. Uptake of Triclosan from PVC diminished the ability of worms to engineer sediments and caused mortality, each by >55%, while PVC alone made worms >30% more susceptible to oxidative stress. As global microplastic contamination accelerates, our findings indicate that large concentrations of microplastic and additives can harm ecophysiological functions performed by organisms.

Capsule: Across the European wintering range Bar-tailed Godwits Limosa lapponica lapponica selected polychaete worms and especially Ragworms Hediste diversicolor, with differences between areas due to variations in prey availability.Aims: To determine the diet of Bar-tailed Godwits across their wintering range in Europe by the analysis of droppings, collected at five important wintering sites.Methods: Diet was estimated by the identification of undigested prey remains in droppings. We provide the rationale for quantifying the contributions of jawed and non-jawed polychaetes.Results: We identified 18 different prey species in the diet of wintering Bar-tailed Godwits. The Ragworm was the most common prey item and the only one actively selected. Ragworms, on average, contributed 79% to the diet in terms of biomass, followed by King Ragworm Alitta virens (with 17% biomass) and Lugworms Arenicola marina (with 2%). Polychaetes such as Alitta succinea and Scoloplos armiger were also regularly found in the diet. Bivalves, snails and crustaceans contributed less than 1% to the diet.Conclusion: This study highlights and confirms the importance of polychaete worms in the diet of European-wintering Bar-tailed Godwits.

Based initially on the morphological similarity between species belonging to Actinocephalus (Korn.) Sano and Paepalanthus Mart. subsect. Aphorocaulon Ruhland (Eriocaulaceae), these taxa were studied to clarify their relationships. After intensive fieldwork and morphological analyses of specimens belonging to Paepalanthus subsect. Aphorocaulon and Actinocephalus, we conclude that Paepalanthus subsect. Aphorocaulon and Actinocephalus should not be classified as different taxa. This taxonomic opinion is confirmed by published phylogenetic morphological and molecular data. We propose herein to include species of Paepalanthus subsect. Aphorocaulon in Actinocephalus. Thus nomenclatural and taxonomic changes are proposed in Actinocephalus and Paepalanthus with the following 16 new combinations: A. actinocephaloides (Silveira) F. N. Costa [≡ P. actinocephaloides Silveira], A. arenicola (Silveira) F. N. Costa [≡ P. arenicola Silveira], A. armeria (Mart. ex Korn.) F. N. Costa [≡ P. armeria Mart. ex Korn....

We investigated the impact of sediment reworking fauna and hydrodynamics on mobilization and transport of organic matter and fine particles in marine sediments. Experiments were conducted in an annular flume using lugworms ( Arenicola marina ) as model organisms. The impact of lugworms on sediment characteristics and particle transport was followed through time in sediments experimentally enriched with fine particles ( − 1 ) to evaluate the importance of sediment erosion at the sediment–water interface. There was no impact of fauna on sediment composition and particle transport at current velocity below the sediment erosion threshold. At current velocity above the erosion threshold, sediment reworking by lugworms resulted in dramatic particle transport (12 kg dry matter m − 2 ) to an adjacent particle trap within 56 days. The transported matter was enriched 6–8 times in fine particles and organic matter when compared to the initial sediment. This study suggests that sediment reworking fauna is an important controlling factor for the particle composition of marine sediments. A. marina mediated sediment reworking greatly increases the sediment volume exposed to hydrodynamic forcing at the sediment–water interface, and through sediment resuspension control the content of fine particles and organic matter in the entire reworked sediment layer (> 20 cm depth).

Seagrass global distribution has declined in the last decades due to many causes, and the implementation of recovery programmes as well as the development of new restoration techniques are needed. This work describes the development of an innovative restoration measure to enhance Zostera marina (eelgrass) seed germination and seedling survival in sediments inhabited by lugworms (Arenicola marina) and its validation in mesocosm experiments. The technique consists of placing 3 cm thick biodegradable coconut fibre mats (membrane) in the surface sediment to exclude the negative effects of sediment reworking (burial of seeds and destabilization/burial of seedlings). Two different flume mesocosm experiments were setup to test for: i) the effect of membranes on burial of Z. marina seeds; ii) the effect of membranes on survival and growth of Z. marina seedlings. The experiments were run for 8 and 10 weeks, respectively. Results show that the membrane was effectively preventing critical burial of Z. marina seeds as all seed mimics placed on the surface initially were recovered from 0 to 4 cm depth in the plots with membrane, while in the absence of the membrane, all seeds were buried to below the critical depth of 5–6 cm. The membrane also significantly enhanced the survival of Z. marina seedlings. The initial seedling density was in both cases 30/m2 and the final density was 26.0 ± 3.3/m2 with membrane versus 8.0 ± 1.6/m2 without membrane. This new marine restoration measure showed to be effective on the reduction of the physical stress imposed by sediment reworking lugworms on Z. marina recovery, as a membrane keeps seeds at optimal depth for germination and protects seedlings from burial and erosion. In comparison to other measures, this new restoration technique is a low-tech nature-based solution. The results clearly show that this restoration technique can support Z. marina recovery through seeds and seedling protection. In this way, this technique contributes to decrease Z. marina vulnerability and increase its natural recovery potential and stability.

espanolLa revision de las especies de Goneplax Leach, 1814, ha arrojado la asignacion de cuatro especies fosiles de Goneplax, pero solo G. gulderi Bachmayer, 1953, y G. rhomboides son consideradas como validas. Goneplax craverii Crema, 1895, previamente asignada a Retropluma Gill, 1894, G. formosa Ristori, 1886, y G. meneghinii Ristori, 1886, son consideradas como sinonimos junior de G. rhomboides, mientras que G. sacci Crema, 1895, es considerada como nomen dubium. Se propone Albaidaplax n. gen. para incluir tanto los especimenes italianos del Mioceno de Rio Popogna (Livorno, Toscana, Italia) como los especimenes espanoles del Plioceno de la Cuenca de Guadalquivir (Sevilla, Andalucia, Espana), previamente asignados a G. gulderi. Finalmente, se asigna Ommatocarcinus arenicola Glaessner, 1960, del Oligoceno Tardio-Mioceno Medio de Nueva Zelanda, al genero existente Neogoneplax Castro, 2007, y constituye el primer registro del genero como fosil. EnglishA revision of the fossil species of Goneplax Leach, 1814, has resulted in the assignment of four fossil species to Goneplax, but only G. gulderi Bachmayer, 1953, and G. rhomboides are considered as valid. Goneplax craverii Crema, 1895, previously assigned to Retropluma Gill, 1894, G. formosa Ristori, 1886, and G. meneghinii Ristori, 1886, are regarded as junior synonyms of G. rhomboides, while G. sacci Crema, 1895, is considered a nomen dubium. Albaidaplax n. gen. is here erected to include both the Italian specimens from the Miocene of Rio Popogna (Livorno, Tuscany, Italy) and the Spanish specimens from the Pliocene of Guadalquivir Basin (Seville, Andalusia, Spain) previously assigned to G. gulderi. Finally, Ommatocarcinus arenicola Glaessner, 1960, from the Late Oligocene-Middle Miocene of New Zealand, is assigned to the extant Neogoneplax Castro, 2007, constituting the first report of this genus in the fossil record.

Plastic is ubiquitous in global oceans and constitutes a newly available habitat for surface-associated bacterial assemblages. Microplastics (plastic particles

Purpose The purpose of this paper is to compare three approaches for providing information on the bioaccumulation potential of metals from contaminated sediments to the deposit-feeding polychaete Arenicola marina.

The developmental cycle of the obligate marine antibiotic producer actinobacterium Salinispora arenicola isolated from a Great Barrier Reef marine sponge was investigated in relation to mycelium and spore ultrastructure, synthesis of rifamycin antibiotic compounds, and expression of genes correlated with spore formation and with rifamycin precursor synthesis. The developmental cycle of S. arenicola M413 on solid agar medium was characterized by substrate mycelium growth, change of colony color, and spore formation; spore formation occurred quite early in colony growth but development of black colonies occurred only at late stages, correlated with a change in spore maturity in relation to cell wall layers. Rifamycins were detected throughout the growth cycle, but changed in relative quantity at particular phases in the cycle, with a marked increase after 32 days. Expression of the spore division gene ssgA and the rifK gene for 3-amino-5-hydroxybenzoate synthase responsible for rifamycin precursor synthesis was seen even at early stages of the growth cycle. ssgA expression significantly increased between days 26 and 31, but rifK expression effectively remained constant throughout the growth cycle, consistent with the early synthesis of rifamycin. Factors other than precursor synthesis may be responsible for an observed late increase in rifamycin production. A useful approach for measuring and exploring the regulation of antibiotic synthesis and gene expression in the marine natural product producer S. arenicola has been established.

Many bacteria produce siderophores for sequestration of growth-essential iron. Analysis of the Salinispora genomes suggests that these marine actinomycetes support multiple hydroxamate- and phenolate-type siderophore pathways. We isolated and characterized desferrioxamines (DFOs) B and E from all three recognized Salinispora species and linked their biosyntheses in S. tropica CNB-440 and S. arenicola CNS-205 to the des locus through PCR-directed mutagenesis. Gene inactivation of the predicted iron-chelator biosynthetic loci sid2-4 did not abolish siderophore chemistry. Additionally, these pathways could not restore the native growth characteristics of the des mutants in iron-limited media, although differential iron-dependent regulation was observed for the yersiniabactin-like sid2 pathway. Consequently, this study indicates that DFOs are the primary siderophores in laboratory cultures of Salinispora.

A study was performed to better understand the taxonomy and diversity of the diatom genus Amphora (Bacillariophyceae) from Korean coastal environments. Samples were taken from six locations at Saemangeum tidal flats on the west coast of Korea. Light microscopic (LM) and scanning electron microscopic (SEM) observations revealed a total of 23 Amphora species. Thirteen were identified to the species level, and ten to the genus level. Three Amphora species viz. A. arenicola, A. beaufortiana and A. maletractata var. constricta were recorded for the first time in Korea. All the Amphora species were listed and presented with morphological descriptions, dimensional information and photographic information.

The Athabasca Sand Dunes in northern Saskatchewan are a unique landscape characterized by large areas of active sand dunes. The dunes are of high conservation value as they support 10 endemic vascular plant taxa, including 9 sand dune specialists: Achillea millefolium var. megacephala, Armeria maritima ssp. interior, Deschamp sia mackenzieana, Salix brachycarpa var. psammophila, Salix silicicola, Salix turnorii, Salix tyrrellii, Stellaria arenicola, and Tanacetum huronense var. floccosum. This paper describes the patterns of distribution, abundance, and environmental affinity of the Athabasca endemic flora and assesses the implications of these patterns for the conservation status of the species. Extensive field surveys found large populations of Deschampsia mackenzieana, Salix brachycarpa, Salix silicicola, Salix turnorii, Salix tyrrellii, Stellaria arenicola, and Tanacetum huronense. With the exception of S. brachycarpa the abundant species were widely distributed across the dune landscape. Tw...

The highest concentrations of environmental contaminants are generally found in marine sediments, and there is a need for knowledge concerning how and whether they affect sediment-dwelling organisms. This study aimed to assess sublethal effects in Arenicola marina exposed to two sediments from a contaminated fjord and two reference locations with different sediment characteristics. Duplicate contaminated sediments were used to investigate the robustness of current protocols for sediment testing. The two reference sediments, with different grain sizes and total organic carbon, were collected from the outer Oslofjord and the two contaminated sediments from Frierfjord. Polychaetes were exposed in quadruplicate sediment microcosms and sampled after 1, 2, 4 and 8 weeks of exposure. Oxidative stress resistance (total oxyradical scavenging capacity, TOSC) and components comprising the energy budget (cellular energy allocation, CEA) were determined for individual polychaetes. Arenicola maintained and increased body weights over the initial 4 weeks of exposure in all groups, except in one reference sediment (Elle). There were no differences between treatments in the scavenging capacity (TOSC). The most striking difference in how polychaetes partitioned energy resources was a difference in lipid and carbohydrate allocations for Arenicola held in the contaminated sediments over the initial weeks. Cellular respiration appeared to increase in polychaetes held in the Elle sediment and decreased for polychaetes held in the two Frierfjord sediments by weeks 4 and 8. In the overall CEA, this was offset by increased energy per weight stored in the Elle group, which resulted in an overall positive CEA for polychaetes held in that sediment, whereas polychaetes in the other treatments were close to neutral. Although CEA would thus indicate that Elle polychaetes had good health status, their body weight also decreased significantly over the experimental period compared to other treatments, indicating an overall negative effect. This study has shown the importance of sediment characteristics when evaluating toxicity and how resource allocation can differ dramatically over a short time span in polychaetes held in similarly contaminated sediments. There were no clear effects of sediment contamination on CEA or TOSC in the polychaete A. marina. The findings are relevant for the design of both short- and long-term sediment studies.

A new species of Remanea Klie, 1929 (Copepoda: Harpacticoida: Paramesochridae) is described from a brackish water habitat near Naksan beach on the east coast of Korea, representing the third species of the genus. The new species was assigned to the genus Remanea on the basis of the well-developed rostrum, the eight-segmented female antennule, the two-segmented antennary exopod and the three-segmented P1 exopod. Remanea naksanensis sp. nov. is most closely related to the type species, Remanea arenicola Klie, 1929, sharing the same armature formula of the swimming legs and the previously overlooked sexual dimorphism on the distal endopodal segment of P3. The new species can be distinguished from its congeners primarily by the morphology of the P5 in both sexes, and setal length differences in the P1 endopod and caudal rami. A brief redescription of R. arenicola is provided based on Klie's original type slide material. The distribution records of all three species are summarized and an updated identification...

Peroxiredoxin 5 (PRDX5) is a thioredoxin peroxidase able to reduce hydrogen peroxide, alkyl hydroperoxides and peroxynitrite. In human, PRDX5 was reported to be localized in the cytosol, the mitochondria, the peroxisomes and the nucleus. Mitochondrial localization results from the presence of an N-terminal mitochondrial targeting sequence (MTS). Here, we examined the conservation of mitochondrial localization of PRDX5 in animal species. We found that PRDX5 MTS is present and functional in the annelid lugworm Arenicola marina. Surprisingly, although mitochondrial targeting is well conserved among animals, PRDX5 is missing in mitochondria of domestic pig. Thus, it appears that mitochondrial targeting of PRDX5 may have been lost throughout evolution in animal species, including pig, with unknown functional consequences.

A culture-independent analysis of the bacterial assemblages in the sediments of a lugworm Arenicola marina L. bioturbated mesocosm was carried out using a molecular RNA-gene based approach. Clone libraries were constructed for 4 spatial locations in the mesocosm: deep yeast layer (DYL), mid sand (MS), new casts (NC) and old casts (OC) after 29 d of bioturbation. In total, 495 clones were analysed and grouped into 159 unique phylotypes. All libraries were dom- inated by Epsilonproteobacteria, with Alpha-, Delta- and Gammaproteobacteria, Verrucomicro- bia and members of the Cytophaga-Flavobacteria-Bacteroides group also prevalent. Phyologe- netic comparison of the sites with respect to evolutionary distance showed that the libraries fell into 2 groups: (1) DYL and MS and (2) NC and OC. There were significant differences in species composition between but not within the 2 groupings. Bacteria involved with sulphur cycling are most likely to be affected by lugworm bioturbation. An Epsilonproteobacterium phylotype with >95% 16S similarity to Sulfurimonas denitrificans was abundant in the DYL sand layer but was not present in the egested sand (NC, OC). Promotion of the growth of sulphide-oxidising bacteria and their subsequent digestion would be consistent with the 'gardening' hypothesis and suggests that chemoautotrophic processes in shallow-water anaerobic sediments may be enhanced by the activities of the lugworm.

In order to investigate the residues associated with binding of the substrate taurocyamine in Arenicola mitochondrial taurocyamine kinase (TK), we performed Ala-scanning of the amino acid sequence HTKTV at positions 67-71 on the GS loop, and determined apparent K(m) and V(max) (appK(m) and appV(max), respectively) of the mutant forms for the substrates taurocyamine and glycocyamine. The appK(m) values for taurocyamine of the K69A, T70A and V71A mutants were significantly increased as compared with wild-type, suggesting that these residues are associated with taurocyamine binding. Of special interest is a property of V71A mutant: its catalytic efficiency for glycocyamine was twice that for taurocyamine, indicating that the V71A mutant acts like a glycocyamine kinase, rather than a TK. The role of the amino acid residue K95 of Arenicola MiTK was also examined. K95 was replaced with R, H, Y, I, A and E. K95R, K95H and K95I have a 3-fold higher affinity for taurocyamine, and activity was largely lost in K95E. On the other hand, the K95Y mutant showed a rather unique feature; namely, an increase in substrate concentration caused a decrease in initial velocity of the reaction (substrate inhibition). This is the first report on the key amino acid residues responsible for taurocyamine binding in mitochondrial TK.

Arenicola marina lives in marine environments where hydrogen peroxide concentrations reach micromolar levels. The annelid also forms reactive species through metabolic pathways. Its antioxidant systems include a cytosolic peroxiredoxin, peroxiredoxin 6 (AmPrx6 or AmPRDX6) that shows high homology to the mammalian 1-Cys peroxiredoxin. Previous work confirmed the peroxidase activity of AmPrx6 in the presence of dithiotreitol. Herein, we performed an in vitro kinetic characterization of the recombinant enzyme. AmPrx6 reduced hydrogen peroxide and peroxynitrite with rate constants of 1.1 × 107 and 2 × 106 M-1 s-1, respectively, at pH 7.4 and 25 °C. Reduction of tert-butyl hydroperoxide was slower. The pKa of the peroxidatic thiol of AmPrx6 was determined as 5.1 ± 0.2, indicating that it exists as thiolate, the reactive species, at physiological pH. The reductive part of the catalytic cycle was also explored. Hydrogen sulfide, present in millimolar concentrations in marine sediments where the annelid lives and that is able to reduce the mammalian 1-Cys peroxiredoxin, did not support AmPrx6 peroxidase activity. The enzyme was not reduced by other potential physiological reductants tested. Our data indicate that in this annelid, Prx6 could contribute to peroxide detoxification in the presence of a so far unidentified reducing counterpart.

During faunistic study on psammophilic ciliates along the coast of Qingdao, China, a population of Trachelocerca arenicola Kahl, 1933 was found and then investigated using silver staining and gene sequencing methods. The results indicated that it represented a new genus Apotrachelocerca characterized by uninterrupted circumoral kineties composed of two rows of dikinetids and no brosse or ciliary tuft in the oral cavity. This new genus should be assigned to the family Prototrachelocercidae Foissner, 1996. Based on the small subunit rRNA gene sequence, phylogenetic trees revealed that Apotrachelocerca arenicola occupied a basal position to other trachelocercids.

The molecular fingerprinting technique terminal-restriction fragment length polymorphism (T-RFLP) was used in combination with sequence-based approaches to evaluate the geographic distribution of secondary metabolite biosynthetic genes in strains of the marine actinomycete Salinispora arenicola . This study targeted ketosynthase (KS) domains from type I polyketide synthase (PKS) genes and revealed four distinct clusters, the largest of which was comprised of strains from all six global locations sampled. The remaining strains fell into three smaller clusters comprised of strains derived entirely from the Red Sea, the Sea of Cortez, or around the Island of Guam. These results reveal variation in the secondary metabolite gene collectives maintained by strains that are largely clonal at the 16S rRNA level. The location specificities of the three smaller clusters provide evidence that collections of secondary metabolite genes in subpopulations of S. arenicola are endemic to these locations. Cloned KS sequences support the maintenance of distinct sets of biosynthetic genes in the strains associated with each cluster and include four that had not previously been detected in S. arenicola . Two of these new sequences were observed only in strains derived from Guam or the Sea of Cortez. Transcriptional analysis of one of the new KS sequences in conjunction with the production of the polyketide arenicolide A supports a link between this sequence and the associated biosynthetic pathway. From the perspective of natural product discovery, these results suggest that screening populations from distant locations can enhance the discovery of new natural products and provides further support for the use of molecular fingerprinting techniques, such as T-RFLP, to rapidly identify strains that possess distinct sets of biosynthetic genes.

Sediment toxicity assessments using caged organisms present advantages over using laboratory and native community studies. The use of caged Arenicola marina in sediment toxicity assessments was evaluated. Lugworms were exposed in situ to sediments from coastal and port areas in Spain for seven days, and the activities of the biotransformation enzymes ethoxyresorufin O-deethylase, dibenzylfluorescein dealkylase and glutathione S-transferase, the activities of the antioxidant enzymes glutathione reductase and glutathione peroxidase and lipid peroxidation were then analyzed as biomarkers. Biomarker results and sediment physicochemical data were integrated. Cádiz Bay (SW Spain) sediments presented metal contamination that was not linked to a biochemical response. In LPGC Port (SW Spain), Pb contamination exhibited a moderate toxic potential, while PAHs, and presumably pharmaceuticals, provoked biochemical responses that efficiently prevented lipid peroxidation. In Santander Bay (N Spain), exposure to PAHs and, presumably, pharmaceuticals induced biomarker responses, but lipid peroxidation occurred nevertheless. These results indicated that caged A. marina were effective for the assessment of sediment quality and that the selected biomarkers were sufficiently sensitive to identify chemical exposure and toxicity.

A short-term whole-sediment test using the polychaete Arenicola marina was conducted under laboratory conditions to assess the bioavailability of metals bound to sediments collected from 12 sites of the Gulf of Cádiz. To achieve this objective, the rate of increase of metal bioaccumulation and the induction of a typical biomarker, metallothioneinlike proteins (MTLPs) were determined. Results of the multivariate analysis showed associated metal-rich sediments, increased rate of Cu and Zn accumulations, but lower toxicity with an increased MTLP induction, whereas sedimentary Ni and Co concentrations were related to higher toxicity to lugworms, although it might be caused by other contaminants present in these sediments. The linear kinetic approach was shown to be valid in certain circumstances, but more validation studies of this parameter are required before it can be recommended for use in evaluating metal bioavailability in sediments., This work was supported by the project “Interreg IIIA Cooperación Transfronteriza España-Portugal, FEDER-EU” (SP3.E101/03). J. K. thanks the i3p program of the Spanish National Research Council for funding her research fellowship.

The sediment quality of Cadiz Bay, Las Palmas de Gran Canaria (LPGC) Port, Santander Bay, Algeciras Bay, and Huelva Estuary (Spain) was evaluated by analysing a battery of biochemical biomarkers―activities of biotranformation enzymes ethoxyresorufin O-deethylase [EROD], dibenzylflourescein dealkylase [DBF], and glutathione S-transferase [GST]; activity of antioxidant enzyme glutathione reductase [GR]; and lipid peroxidation [LPO]―in the polychaete Arenicola marina after laboratory sediment exposure. Huelva Estuary polychaetes showed significantly (p

Benthic ecosystem engineering organisms attenuate hydrodynamic or biogeochemical stress to ameliorate living conditions. Bioturbating infauna, like the lugworm Arenicola marina, determine intertidal process dynamics by maintaining the sediment oxygenated and sandy. Maintaining the permeability of the surrounding sediment enables them to pump water through the interstitial spaces, greatly increasing the oxygen availability. In a field experiment, both lugworm presence and siltation regime were manipulated to investigate to what extent lugworms are able to cope with sedimentation of increasing mud percentage and how this would affect its ecosystem engineering. Fluorescent tracers were added to experimentally deposited mud to visualise bioturbation effects on fine sediment fractions. Lugworm densities were not affected by an increasing mud percentage in experimentally deposited sediment. Negative effects are expected to occur under deposition with significantly higher mud percentages. Surface chlorophyll a content was a function of experimental mud percentage, with no effect of lugworm bioturbation. Surface roughness and sediment permeability clearly increased by lugworm presence, whereas sediment erosion threshold was not significantly affected by lugworms. The general idea that A. marina removes fine sediment fractions from the bed could not be confirmed. Rather, the main ecosystem engineering effect of A. marina is hydraulic destabilisation of the sediment matrix.

Eelgrass coverage in Odense Fjord (Denmark) has declined by 90% since 1983, due to eutrophication and its associated pressures, and the state of low eelgrass coverage has remained sta- ble despite 10 to 15 yr of reduced nutrient loading and improved water quality. We hypothesize that the survival of eelgrass seedlings, and thus recolonization through reproductive dispersal, is nega- tively affected by physical disturbances. The 3 most likely physical mechanisms involved are uproot- ing or burial through drifting macroalgae, Arenicola marina sediment reworking and current-driven sediment resuspension. Our hypothesis was tested by field observations during the summer of 2009, when the mortality of seedlings was followed through time. The density of seedlings decreased dra- matically by 80% during the first month of observations, and no seedlings survived past August, cor- responding to an average seedling mortality of 1.5% d -1 . This was >3 times higher than the mortal- ity for seedlings protected from physical disturbance by enclosures (0.4% d -1 ), indicating that physical disturbance contributed to high seedling mortality. A significant correlation (p = 0.02) between macroalgal drift and seedling mortality suggested that ~40% of seedlings were lost due to the physical disturbance of drifting algae. In contrast, no correlations were found between A. marina reworking or resuspension and seedling mortality, despite a mobility of up to 400 cm 3 sediment m -2 d -1 by these mechanisms. Given the observed intensity of macroalgal drift, we speculate that this

The Balgzand intertidal is an important nursery area for early life stages of various epibenthic crustacean and fish species. Especially in summer, extremely high numbers of individuals occur. This study analyses whether these high densities in summer lead to food limitation using 0-group plaice Pleuronectes platessa L. as a model species. Between 1975 and 2007, this species was quantitatively monitored during 20 yr. The aim of this study is twofold: (1) a statistical analysis of field growth in relation to density, whereby negative density-dependent growth is considered as an indi- cation of intraspecific competition, and (2) a comparison of observed field growth with predicted maximum growth according to the dynamic energy budget (DEB) model, to detect whether growth reduction occurs during the growing season as an indication of interspecies competition. The statisti- cal analysis indicated no negative density-dependent growth during the whole growing season, sug- gesting the absence of intraspecies competition for food. The comparison of observed growth with DEB-predicted maximum growth showed that field growth was lower than the possible maximum, and that the difference increased over time until about the end of July, suggesting interspecies com- petition for food in summer. The stabilization in growth rate from July onwards might be related to a change in food quality: a shift from small bivalve siphons as main food items to larger tail tips of the lugworm Arenicola marina. These findings illustrate that not only food quantity but also food quality affects growth rates, at least in 0-group plaice.

The concentration of polycyclic aromatic hydrocarbons (PAHs) in sediment and excrements of annelids was measured by gas chromatography-mass spectrometry (GC/MS) and the movement of PAHs in the tidal flat was investigated. The PAH concentrations ranged 4.4–80.4 and 61.2–286.9 μg/kg-dry for the excrement of Arenicola basiliensis and of Marphysa sanguinea, respectively; the former contained about 10 times as much PAHs as the sediment and the latter about 100 times. The difference in the PAH concentration between the two organisms was attributed to their feeding behavior; M. sanguinea intakes much more detritus containing PAHs than A. basiliensis. Moreover, after the excrement of M. sanguinea had stood on the sediment for 2 hours, the PAH concentrations decreased to half. The reduction of the PAHs may arise from chemical changes owing to microorganisms and/or enzymes in the excrement of M. sanguinea.

We followed the net accumulation of As, Cu and Zn in the deposit-feeding polychaete Arenicola marina exposed in the laboratory to natural metal-contaminated sediments, one exposure leading to mass mortality between day 10 and 20, and the other not causing lethality over a period of 60 days of exposure. The worms showed lower total accumulated metal concentrations just before mortality occurred (

Arenicochrome, a green granular pigment in the epithelial cells of Arenicola marina L., first described histologically and histochemically by Lignac, was extracted from the worm by means of ammoniacal alcohol containing cyanide. After chromatography on aluminium oxide, crystallization of the pigment as a potassium salt was achieved. The formula of this salt proved to be (C21 H15 S2 O14 K3)n where n = 1 or n = 2. Of the three salt-forming groups (minimum formula) one has a pK of 5.7; the dissociation of this group is accompanied by a colour-shift from orange to blue. The two remaining groups are of a strong acid character. The absorption spectra of the compound at different pH values are reported. Some biological problems resulting from the investigation are briefly discussed. In addition some other properties of he pigment are mentioned.

Recent studies of extra-Amazonian species of Copaifera revealed several nomenclatural problems. We choose lectotypes for C. cearensis Huber ex Ducke and C. cearensis var. arenicola Ducke from amongst the available syntypes, and propose the lectotypification of C. langsdorffii Desf. with its original plate. Comments are made about the correct spelling of the specific epithet of C. langsdorffii and the typifications of C. elliptica Mart. and C. luetzelburgii Harms are clarified.

Based on a large-scale, long-term lugworm exclusion experiment established on an intertidal sand flat in Konigshafen (Sylt, North Sea), the effect of ecosystem engineering by the lugworm Arenicola marina on the meiofaunal community was studied. Samples for sediment and meiofauna analyses were taken from a lugworm exclusion plot three years after lugworms were excluded, a disturbed control plot and a pristine ambient plot. Statistical analyses revealed significantly higher concentrations of total organic matter and chloroplastic pigments at the lugworm exclusion site. The median abundance of total meiofauna was 21–29% higher at the lugworm-free site as compared to the lugworm-inhabited sites. Copepoda and Nematoda were distributed homogeneously over all experimental plots while Ostracoda and copepod nauplii reached their highest abundances in the absence of lugworms. Univariate and multivariate analyses revealed significant differences between the copepod species composition of the experimental sites. While the harpacticoid copepod Arenosetella germanica reacted with a decline in individual numbers to lugworm exclusion, Halectinosoma gothiceps and Asellopsis intermedia benefited from the induced changes in the sediment characteristics. Overall, a higher copepod species diversity and evenness was observed at the lugworm exclusion site. The results of this study indicate that sediment-mediated effects of bioturbating organisms influence the abundance and diversity of surface-living meiofauna.

The ecotoxicology of manufactured nanoparticles (MNPs) in estuarine environments is not well understood. Here we explore the hypothesis that nanoTiO 2 and single walled nanotubes (SWNT) cause sublethal impacts to the infaunal species Arenicola marina (lugworm) exposed through natural sediments. Using a 10 day OECD/ASTM 1990 acute toxicity test, no significant effects were seen for SWNT up to 0.03 g/kg and no uptake of SWNTs into tissues was observed. A significant decrease in casting rate ( P = 0.018), increase in cellular damage ( P = 0.04) and DNA damage in coelomocytes ( P = 0.008) was measured for nanoTiO 2 , with a preliminary LOEC of 1 g/kg. Coherent anti-stokes Raman scattering microscopy (CARS) located aggregates of TiO 2 of >200 nm within the lumen of the gut and adhered to the outer epithelium of the worms, although no visible uptake of particles into tissues was detected.

We employed real-time pressure recording and high temporal resolution two-dimensional oxygen imaging to characterize the porewater bioadvection related to hydraulic activities of Arenicola marina, a widespread representative of benthic macrofauna. Behavior-specific positive and negative pressure oscillations and hydraulic pulses resulted in bidirectional porewater flow and highly dynamic redox oscillations on the scale of minutes. Pumping of water by the worm into its blind-ending burrow pressurized the sediment and caused sediment oxygenation at depth and the exit of anoxic porewater into the overlying water. The sediment volume that was affected by bioadvective transport of oxygen and the porewater flow patterns varied strongly among sediment types. In low-permeability sediments, localized plumes of anoxic porewater ascended from the sediment, presumably through sedimentary cracks, while porewater flowed evenly through highly permeable sediments. Hydraulic behaviors that moved water out through the open tail shaft caused a reduction of porewater pressures below the hydrostatic baseline which resulted in the collapse of plumes and enhanced oxygen penetration into the surficial sediments. Porewater bioadvection and the related perfusing and oscillatory phenomena will affect a variety of biogeochemical and ecological processes, including organic matter mineralization, benthic recruitment, and prey localization. We suggest that bidirectional porewater bioadvection and the associated transient geochemical conditions are prevalent features of biogenically active sediments.

The benthic microbial food web can be responsible for a large proportion of benthic carbon cycling yet there are few data on the trophic interactions between this food web and macrobenthos. A large-scale field experiment was conducted to investigate effects of eliminating the polychaete Arenicola marina on benthic microbes (prokaryotes, heterotrophic and autotrophic protists) and metazoan meiofauna in a marine intertidal flat of the North Sea, Germany. Over a period of 2 years, quantity and composition of micro- and meiobenthos from unmanipulated sites were compared to those from sites deplete of lugworms. These grazer treatments were cross-classified with different sediment characteristics (low- and mid-intertidal areas). Lugworm removal resulted in an initial increase in abundance of prokaryotes and nanoflagellates, which became less pronounced in the second year. Ciliates were not affected quantitatively, but in the absence of lugworms, diversity and the proportion of carnivorous forms increased. Meiobenthos (nematodes, ostracods and copepods) were affected only moderately. The observed changes are probably due to a combination of release from grazing/predation pressure, changes in the species composition of higher trophic levels (namely large polychaetes) and altered environmental conditions (such as depth of the oxygenated layer and sediment grain size). Spatial differences between sites of different tidal exposure/grain size appeared to be as large as temporal differences during the 2 years following the manipulation of the system. We conclude that in intertidal sediments, indirect effects due to habitat transformation are as important as direct biological interactions (grazing pressure and competition) for the dynamics of the benthic microbial food web.

The Algodones dunes in southeastern California are among the largest dunes systems in North America comprising roughly 700 km2. Our 2-year inventory of the insects of these dunes has revealed a fauna of more than 1100 species, including more than 60 species new to science. Among these are 21 species of Pompilidae given in a table, including Ageniella (Ageniella) arenicola Wasbauer and Kimsey, sp. nov., and Ageniella (Priophanes) pernia Wasbauer and Kimsey, sp. nov., described herein.

The polychaete Arenicola defodiens, or black lug, was recently described as a morphologically highly similar species alongside the blow lug Arenicola marina . So far it was only known from the British Isles. A double spawning peak was observed earlier in lugworms of the western Wadden Sea. Here, we test the hypothesis that the two spawning peaks represent the two species in sympatry. This hypothesis is refuted on the basis of both morphological and mitochondrial DNA data; both spawning peaks are attributed to A. marina . In spite of this, we confirm, on the basis of new collections as well as re-examination of museum collections, the presence of A. defodiens in the western Wadden Sea, North Sea and also the Skagerrak; its distribution is restricted to habitats which are either submerged or have short emersion times, have relatively coarse sediments and high and stable salinities. Sympatry is common. The species differ strongly in the mitochondrial DNA fragment examined; the observed 14% uncorrected minimum difference amounts to an estimated 33–63 million years since sequence divergence. The amount of intraspecific molecular variation is larger for A. defodiens than for A. marina . This is evidence to suggest that A. marina may have undergone more recent and/or more severe population size bottlenecks.

The capitellid genus Notodasus Fauchald, 1972 is emended and its previously known species are redescribed. Since the original descriptions of N. magnus Fauchald, 1972, N. dexterae Fauchald, 1973, and N. arenicola Hartmann-Schroder, 1992 omitted important morphological details and were either incomplete or misleading, these species are redescribed based upon examination of type materials. Four new species are described from tropical localities in Mexico: Notodasus harrisae n. sp., N. hartmanae n. sp., N. kristiani n. sp. and N. salazari n. sp. Standardised descriptions are provided for all species including the methyl green staining pattern, the epithelial texture and the shape of hooded hooks. A key for all described species is provided.

The hydraulic activities of two arenicolid polychaetes, Abarenicola pacifica and Arenicola marina, result in strikingly similar pressure waveforms. The principal hydraulic activities are defecation, burrowing and feeding/burrow maintenance. Both the duration and magnitudes of the pressures are very similar. The behavioral periodicities of the two species are also quite similar, although burrowing is more common in A. pacifica than in A. marina. Additionally burrowing activities in A. marina appear to be more influenced by tidal stage than those in A. pacifica. The link between burrowing and pore-water pressure reductions makes this difference potentially important in terms of drawing oxygenated water into surface sediments

Concentrations of Fe, Zn, Cu, Pb and Cd were measured in four surface sediments, whole worm tissues and faeces collected along Aguas de Moura channel in Sado estuary. Six wet-weight worm classes were used to analyze the influence of weight. The metal concentration in colonized sediments is high for Fe and Cu, moderate for Pb and Zn, and low for Cd. The analyses of whole worm tissues show that Zn, Cd and Cu are accumulated. Considering the elevated sediment concentrations to which this species is exposed, the high levels of Zn and Cu suggest sequestration and Cu adaptation. However, the low Fe concentration indicates that this metal is not readily available. The similar Pb behaviour also suggests low availability or Fe interference. The high correlation in the sediment between Pb and Fe reinforces this suggestion. The results obtained show that Pb, Zn and Fe are the most important metals in the different weight classes. The overall results of this study show: (1) that this worm is able to adapt physiologically to elevated levels of metals; and (2) that the weight of the worms needs to be taken into account in environmental management programmes.

Global warming trends in the marine environment currently lead to poleward shifts in the distribution of marine fauna along European coastlines indicating limited thermal tolerance of affected species and potential loss of their southernmost populations. The present study analyses the degree and limits of thermal specialisation in various populations of a key species of the intertidal zone, the lugworm Arenicola marina, which is exposed to highly fluctuating conditions in temperature, salinity, pH and oxygen levels during the seasonal as well as the tidal cycle. Thermal windows of tolerance and exercise performance were compared in three populations from the Russian White Sea, the German North Sea and the French Atlantic coast. Digging experiments in natural marine sediments quantified performance capacity and its optimum temperature. Temperature dependent ventilation and respiration were analysed in lugworms dwelling in artificial self-perfused burrows. Haemoglobin oxygen affinity was examined for an evaluation of population specific adaptations in the oxygen supply system. The results reflect a shift of both the thermal window and the thermal optimum towards higher temperatures with decreasing latitude. This shift was accompanied by a reduction of performance amplitude, i.e. the absolute number of digging periods, and a widening of the distance between critical temperatures, i.e. the total aerobic window of thermal tolerance.

Effective management of eutrophic ecosystems requires an understanding of how nutrient input affects the structure and function of benthic communities. The effects of nutrients in soft sediment habitats can be influenced by a variety of factors including sediment characteristics, hydrodynamic exposure, and the presence of bioturbating macroinvertebrates. We used a large scale exclusion experiment (400 m 2 areas, n = 6) to test if bioturbating lugworms, Arenicola marina mediate the effects of nutrient enrichment. We incorporated small plots (30 × 30 cm) dosed with household garden fertilizer within the lugworm exclusion and corresponding control areas and predicted that the effects of nutrient enrichment would be greater in the absence of lugworms. We found that the increases in nutrient concentrations were higher in the absence of lugworms, but only in the less permeable sediment in the low intertidal zone compared to the more permeable sediment in the high intertidal. Contrary to expectations, the accumulation of nutrients in the plots did not affect the organic matter and chlorophyll levels in the sediment. Interestingly, there were overall negative effects of nutrient additions on some of the most abundant molluscs, Hydrobia ulvae , Retusa obtusa and juvenile Cerastoderma edule . Possible explanations for these adverse effects such as the changes in the sediment chemistry or the physical presence of the fertilizer in the sediment caused by the nutrient additions are discussed. We conclude that the effects of nutrient enrichment in soft sediment habitats on benthic assemblages are determined by the interplay between the presence of bioturbating macroinvertebrates, tidal height and sediment characteristics.

Pinnixa arenicola is redescribed and illustrated on the basis of new collections and reexamined type material. Its occurrence in the burrows of Upogebia vasquezi Ngoc-Ho is reported, along with range extensions that include Florida, Puerto Rico, Aruba, and the Cayman Islands. New collections represent the first reports of P. arenicola since original discoveries in Curacao and suggest a potentially wide distribution of the species in the tropical western Atlantic. Following publication of the unillustrated original description for the holotype male, females were also noted to occur in Curacao, but illustrations with limited detail were provided by Rathbun for only the male holotype specimen. Prior to our work, no illustrations have depicted female morphology, unique male gonopods, or some pereopod features of potential value in defining phylogenetic relationships.

International audience; This work reports for the first time the expression of a soluble B2 globin chain that is part of the extracellular hexagonal-bilayer haemoglobin from Arenicola marina. Two recombinant B2 globins were produced, one fused with gluthatione S-tranferase (B2-GST) and the other without a fusion tag (RecB2) and requiring a different purification procedure. We also describe a new method for the expression of globin that uses Studier's auto-induction medium together with the heme precursor -aminolevulinic acid. Media supplementation with the heme precursor -aminolevulinic acid in the culture increased heme synthesis by E. coli leading to the expression of the recombinant B2 globins in their active form. RecB2 and B2-GST were expressed with a yield of up to 105 mg/l of E. coli culture. Our approach is rapid and requires only one chromatographic purification step for B2-GST and three purification steps for RecB2. The overall results on RecB2 and B2-GST show that the recombinant globins exhibit similar properties to those of Arenicola marina native HBL-Hb with a great stability and a strong oxygen binding. The results and methodologies described in this paper are the beginning of a work aiming at reconstituting a recombinant HBL-Hb by genetic engineering in order to produce an innovative oxygen carrier for therapeutic applications.

Three new cyclohexadepsipeptides, arenamides A-C (1-3), were isolated from the fermentation broth of a marine bacterial strain identified as Salinispora arenicola. The planar structures of these compounds were assigned by detailed interpretation of NMR and MS/MS spectroscopic data. The absolute configurations of the amino acids, and those of the chiral centers on the side chain, were established by application of the Marfey and modified Mosher methods. The effect of arenamides A and B on NFkappaB activity was studied with stably transfected 293/NFkappaB-Luc human embryonic kidney cells induced by treatment with tumor necrosis factor (TNF). Arenamides A (1) and B (2) blocked TNF-induced activation in a dose- and time-dependent manner with IC(50) values of 3.7 and 1.7 microM, respectively. In addition, the compounds inhibited nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production with lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Moderate cytotoxicity was observed with the human colon carcinoma cell line HCT-116, but no cytotoxic effect was noted with cultured RAW cells. Taken together, these data suggest that the chemoprevention and anti-inflammatory characteristics of arenamides A and B warrant further investigation.

Eight polycyclic aromatic hydrocarbons (PAHs) including benzo[a]pyrene were analyzed in sediment and benthos collected on the coast of Chiba Prefecture in Japan by gas chromatography-mass spectrometry (GC/MS). The total concentration of the PAHs ranged from 8 to 18 μ g/kg-dry in the sediments and from 36 to 59 μ g/kg-wet in the benthos, Mactra quadrangularis, Scoletoma nipponica, and Arenicola basiliensis. The PAH composition in the sediments and the benthos was similar at four sampling points and dominated by phenanthrene (Phe), fluoranthene (Flu), and pyrene (Pyr). The ratios of abundance of Flu to that of Pyr, Flu/Pyr, and of Phe/anthracene suggest that the PAHs in the benthos are derived from the combustion of fossil fuels. The ratio, R, of the PAH concentration in the benthos to that in the sediment is 2.0 for Scoletoma nipponica and 1.8 for Arenicola basiliensis in average, indicating that the bioaccumulation is not significant in the benthos. However, the R value for perylene in Scoletoma nipponica...