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Pikeperch (Sander lucioperca) is a freshwater fish that has become increasingly popular as a food fish. Within this study, the influence of the spawning process on meat quality was investigated. For this purpose, adult pikeperch was examined directly before and after spawning, and compared regarding physical meat parameters and lipid composition. The results indicate that after spawning, the values of the pH, the electrical conductivity and the yellowness value of fillet were significantly higher than those of the animals sampled before spawning. Analysis of the sum of the total lipid content indicates no differences before and after closed season, but differences in the fatty acid profile were present. Despite significant lower MUFA concentrations, the EPA and DHA showed unaffected high contents. Therefore, the fish muscle indicated an equivalent meat quality. Nevertheless, the significant changes of some physical meat quality parameters after spawning season could have a particular impact on the shelf life and storage of the pikeperch fillet, highlighting the need for further research.

Commercial feeds, encoded by letters A, B, and C, with crude protein between 49.1% and 52.9% and crude fat between 13.0% and 22.2% produced especially for percids were fed to European perch (Perca ...

The functional spectrum of the teleostean head kidney covers haematopoietic, immune and endocrine signalling pathways with physiological effects that are likely to conflict if activated at the same time. An in vivo experiment on the salmonid fish maraena whitefish (Coregonus maraena) revealed that the head kidney shows a remarkably strong response after injection of Aeromonas salmonicida within 48 h. In order to investigate the potential influence of endocrine signalling on the initiation of immune responses, we established a primary culture of head-kidney cells of maraena whitefish. For the characterisation of this model system, we used flow cytometry complemented with an extensive panel of immunological/haematological and stress-physiological/neuroendocrinological qPCR assays. More than one third of the cells expressed the characteristic signature of myeloid cells, while more than half of the cells expressed those genes typical for lymphocytes and monocytes. In parallel, we quantified the expression of genes encoding endocrine receptors and identified ADRA2D as by far the most highly expressed adrenergic-receptor gene in head-kidney cells. The stimulation of the head-kidney cells with toll-like receptor ligands induced the expression of typical immune genes (IL1B, CXCL8, TNF, SAA) after only 1 h. The incubation with the stress hormones cortisol, adrenaline and noradrenaline also had an immune-activating effect, though less pronounced. However, cortisol had the strongest suppressive effect on the stimulation-induced immune response, while adrenaline exerted a comparably weaker effect and noradrenaline was almost ineffective. Moreover, we found that cortisol reduced the expression of genes coding for adrenergic and some glucocorticoid receptors, while noradrenaline increased it. In conclusion, the primary head-kidney cells of maraena whitefish reflect the immunological and neuroendocrinological diversity of the entire organ. This in vitro system allowed thus identifying the correlative changes between the activities of hormones and immune factors in salmonid fish in order to contribute to a better understanding of the regulation circuit between stress and immune defence.

The growth of fishes and their metabolism is highly variable in fish species and is an indicator for fish fitness. Therefore, somatic growth, as a main biological process, is ecologically and economically significant. The growth differences of two closely related salmonids, rainbow trout (Oncorhynchus mykiss) and maraena whitefsh (Coregonus maraena), have not been adequately studied as a comparative study and are therefore insufficiently understood. For this reason, our aim was to examine muscle growth in more detail and provide a first complex insight into the growth and muscle metabolism of these two fish species at slaughter size. In addition to skeletal muscle composition (including nuclear counting and staining of stem and progenitor cells), biochemical characteristics, and enzyme activity (creatine kinase, lactate dehydrogenase, isocitrate dehydrogenase) of rainbow trout and maraena whitefish were determined. Our results indicate that red muscle contains cells with a smaller diameter compared to white muscle and those fibres had more stem and progenitor cells as a proportion of total nuclei. Interestingly, numerous interspecies differences were identified; in rainbow trout muscle RNA content, intermediate fibres and fibre diameter and in whitefish red muscle cross-sectional area, creatine kinase activity were higher compared to the other species at slaughter weight. The proportional reduction in red muscle area, accompanied by an increase in DNA content and a lower activity of creatine kinase, exhibited a higher degree of hypertrophic growth in rainbow trout compared to maraena whitefish, which makes this species particularly successful as an aquaculture species.

Eutrophication remains an environmental challenge in lagoons along the Southern Baltic Sea. Floating islands planted with emergent macrophytes are an option to remove nutrients from eutrophicated waters. Furthermore, floating wetlands offer other ecosystem services such as the provision of habitats. Numerous scientific studies have been conducted; however most remain on the laboratory scale. This research explores the challenges associated with installations in coastal environments and focuses on sustainability of the island design, the habitat function as well as nutrient removal. Most floating wetland designs use polyethylene, polypropylene, polyurethane or polyvinyl alcohol foam to ensure the buoyancy. For this study an artificial polymer free island design was developed and tested. The floating constructions in the Darss-Zingst-Bodden-Chain were planted with native macrophytes which have the potential to act as ‘biodiversity-supplements’ to the adjacent coastal wetlands: Bolboschoenus maritimus, Carex acutiformis, Iris pseudacorus, Juncus effesus, Lythrum salicaria, Schoenoplectus lacustris, Typha latifolia. The chosen macrophytes survived fluctuating salinities. After three months the above-ground biomass was harvested and analyzed for the nutrient concentrations. Phosphorus concentrations were highest in L. salicaria and nitrogen in I. pseudacorus. Video monitoring and field observations were applied in order to observe animals. Birds did not use the floating wetlands as breeding grounds, but the grey heron (Ardea cinerea) was a common visitor for foraging. Especially surprising was the large amount of juvenile eels (Anguilla anguilla). A diverse and large root network below the floating islands boosts not only nutrient removal but serves as a shelter and refuge for fish such as the endangered eel.

Despite intensive stocking programmes, wild Maraena whitefish Coregonus maraena (Bloch, 1779)‐stocks are in danger of extinction in the Baltic sea region. Current aquaculture rearing methods in recirculating aquaculture systems (RAS) are lacking efficient protocols for transitioning larvae from endogenous to exogenous feeding. In this 34‐day‐experiment the offspring of wild fish was used. Maraena whitefish larvae were weaned at three different temperatures (15.9°C, 17.9°C, 19.7°C) and three feeding regimes, resulting in nine treatments. The first group received pure live feed (freshly hatched Artemia sp. nauplii) for 10 days and a 1:1‐mixture of live and dry feed for 3 days. The second group received the live and dry feed mixture for 13 days and the third group directly received a commercial dry feed. All nine treatments were stocked in triplicate with 500 larvae per tank (19 ind. L⁻¹). Feeding started 4 days post hatch. Survival was highest in the pure dry feed groups and lowest in the pure live feed groups. In contrast to growth, which was highest in the live feed groups and lowest in the dry feed group. Higher temperature increased growth in the live feed groups but had no effect on survival in all groups. These results will enhance the weaning of C. maraena in recirculation aquaculture.

In vertebrates, the carbohydrate polymer polysialic acid (polySia) is especially well known for its essential role during neuronal development, regulating the migration and proliferation of neural precursor cells, for instance. Nevertheless, sialic acid polymers seem to be regulatory elements in other physiological systems, such as the reproductive tract. Interestingly, trout fish eggs have polySia, but we know little of its cellular distribution and role during oogenesis. Therefore, we localized α2,8-linked N-acetylneuraminic acid polymers in the ovaries of Coregonus maraena by immunohistochemistry and found that prevalent clusters of oogonia showed polySia signals on their surfaces. Remarkably, the genome of this salmonid fish contains two st8sia2 genes and one st8sia4 gene, that is, three polysialyltransferases. The expression analysis revealed that for st8sia2-r2, 60 times more mRNA was present than st8sia2-r1 and st8sia4. To compare polysialylation status regarding various polySiaT configurations, we performed a comparable analysis in Sander lucioperca. The genome of this perciform fish contains only one st8sia2 and no st8sia4 gene. Here, too, clusters of oogonia showed polysialylated cell surfaces, and we detected high mRNA values for st8sia2. These results suggest that in teleosts, polySia is involved in the cellular processes of oogonia during oogenesis.

Stocking density is considered as a key factor determining the productivity of fish aquaculture systems. The transcriptomic response to crowding stress is, however, still poorly investigated. We aimed to identify potential biomarker genes via microarray analyses to gain insight into molecular pathways modulated by density-induced stress in farmed rainbow trout Oncorhynchus mykiss. Transcriptome profiling in the liver, kidney, and gills was complemented by analysis of classical plasma parameters and behavioural observations. Individuals of two trout strains were exposed for nine days to definite stocking densities, ~ 10 kg/m3 (low density); ~ 30 kg/m3 (moderate); ~ 60 kg/m3 (elevated); and ~ 120 kg/m3 (high). Only the PYGMA gene, encoding the key enzyme of glycogenolysis, was upregulated in gills and kidney, while about 90 genes were differentially regulated in the liver of trout exposed to high density compared with the moderate-density group. Pathway enrichment analyses predicted the upregulation of HIF1A signalling in liver, contributing to glucose homeostasis during stress conditions. This is consistent with the increased plasma glucose levels detected in crowding-stressed trout. The mTOR and PI3K/AKT signalling pathways were impaired in liver at higher stocking densities indicating stress at the cellular level. Contrary to our expectations, protein ubiquitination and cholesterol biosynthesis pathways were found to be underexpressed. Cholesterol is a precursor of the stress hormone cortisol, whose plasma concentrations were indeed within the normal physiological range in all treatment groups. In addition, we did not observe any aggressive interactions, which are known to be triggered through cortisol release. Taken together, we identified a relatively modest number of rainbow trout-specific crowding markers suggesting that farmed rainbow trout have gained enhanced stress-tolerant phenotypes through decades of selective breeding. Statement of relevance The comprehensive recording of animal-based biomarkers is becoming increasingly important for the further development of the aquaculture industry with importance for fish well-being and consumer opinion. Previous studies on crowding stress in rainbow trout have used single or multi-gene approaches to assess the relevance of putative biomarkers, but transcriptomic approaches to define crowding stress-induced pathways in salmonids are overdue. The present study compares the transcriptomic profiles of rainbow trout exposed to different stocking densities and correlates these data sets with classical plasma parameters and behavioural observations.

Newly hatched Coregonus maraena (Bloch) larvae reared in aquaria were observed during two trials in 2014 and 2015 for 42 and 34 days after hatching in order to determine the on-feeding effects of different feeding strategies on growth and survival. Feeds of commercial dry feed, live Artemia nauplii, frozen rotifers, and mixtures of these were compared. Larval whitefish were fed brine shrimp for up to 13 days beginning 4 days post hatch (dph). Whitefish larvae fed live Artemia for 8-9 h per day over a period of 10-12 days grew considerably larger (mean value of final total length (TL) 27.3-33.0 mm)) and were heavier (mean value of final body weight (BW) 112-165 mg)) than those fed dry feed, frozen rotifers, or Artemia for 3-6 days (TL= 22.6-30.2 mm; BW= 50-102 mg). The growth of larvae fed for 24 h solely on dry food was comparable (BW= 101 mg, TL= 26.6 mm) at 42 dph. Survival differed among groups (31-63%) and was highest for larvae fed dry food exclusively. Our results can improve the first feeding of Maraena whitefish larvae in small-scale fish farms.

The small polychaete family Trochochaetidae is monogeneric and had been recorded almost exclusively in the northern hemisphere before this study. During a benthic investigation in the coastal shelf zone off Angola at 15°S several specimens were collected from 84 m depth differing from other members of the family and we described it as a new species herein. The only known African species so far was Trochochaeta kirkegaardi from the eastern Atlantic. Trochochaeta ankeae sp. nov. is characterized by having four minute eyes, a small conical antenna, a nuchal crest projecting through chaetiger 2, by lacking notochaetae on chaetiger 2, by having acicular spines on neuropodia 2 and 3 and a pair of conical papillae ventral on abdomen. A key to all 11 known species (including an unnamed one) is given.

Zusammenfassung Die Ortskennung auf deutschen Kfz-Kennzeichen kann als Symbol für die Marke einer Stadt interpretiert werden. Der Beitrag befasst sich mit der daraus zu folgernden Vermarktungswirkung für die durch das Kennzeichen repräsentierte Gebietskörperschaft. Es wird vorgeschlagen, mit mehr als einer Ortskennung pro Zulassungsbezirk die in einem Landkreis vorhandenen räumlichen Produkte differenzierter zu repräsentieren.

Grandidierella elongata Chevreux, 1925 and a new species of the same aorid genus, G. ischienoplia sp. nov., are described from samples collected in coastal shelf zones off Angola, in 2004. The genus Grandidierella is now represented in West and South Africa by nine species. G. ischienoplia sp. nov. is closest to G. nyala Griffiths, 1974. Grandidierella elongata Chevreux, 1925 und eine neue Amphipodenart dieser Gattung, G. ischienoplia sp. nov., werden von Proben der Kustenschelfzone von Angola beschrieben, die im Jahre 2004 gesammelt wurden. Die Gattung Grandidierella , wird nun in West- und Sudafrika von neun Arten reprasentiert. G. ischienoplia sp. nov. ahnelt G. nyala Griffiths, 1974.

A benthological survey in the Benguela upwelling area off northern Namibia (located at 17.3°S and water depth ranging between 26 and 117 m) showed the concentration of dissolved oxygen and the accumulation of organic-rich sediments to control macrozoobenthic community patterns. In contrast to highly biodiverse nearshore areas with well-structured shell deposits of the brachiopod Discinisca tenuis (Sowerby 1847), the benthic community in the oxygen minimum zone (OMZ) decreased strongly in species numbers. Nevertheless, a well-established community ranging from 13 to 31 species persisted. Species densities (300–3,350 ind m−2) and biomass (4–109 g afdw/m2) were surprisingly high for areas with near bottom oxygen concentrations from 0.06 to 0.88 ml l−1. In contrast to OMZ’s of other upwelling areas, where the benthic macrofauna is generally dominated by small-bodied polychaetes, off Namibia larger key organisms like the bivalve Nuculana bicuspidata (Gould 1845) and the snail Nassarius vinctus (Marrett 1877) accounted for a large proportion of the macrozoobenthos >1 mm. This is supposed to have a distinct effect on the functional properties of the sediments.

Electrical currents in underwater sea cables could induce magnetic fields. The sea cables lie on or within the sea bottom and this is the living area for many invertebrate and vertebrate species. North Sea prawn Crangon crangon (Crustacea, Decapoda), round crab Rhithropanopeus harrisii (Crustacea, Brachyura), glacial relict isopod Saduria entomon (Crustacea, Isopoda), blue mussel Mytilus edulis (Bivalvia), and young flounder Plathichthys flesus (Pisces) were exposed to a static magnetic field (MF) of 3.7 mT for several weeks. The results showed no differences in survival between experimental and control animals. Mussels M. edulis were kept under static magnetic field conditions for 3 months during their reproductive period in spring. The determination of gonad index and condition index revealed no significant differences to the control group.

There is direct correlation between building powerful destination brands and the degree to which tourists and locals share the brands values. The massive penetration of the active population by Generation Y has generated a major shift in tourism marketing, based on the profile of this cohort. The members of Generation Y are very different from previous generations. The so-called “digital natives” share high technological proficiency; they like to share their skills; they are disloyal consumers; and they are affected by trends. In order to connect with members of Generation Y and to actively involve them into the life of tourist destinations, viral, participative, interactive, networked and versatile marketing techniques should be employed. This article introduces the Intelligent Solution for Brand Culturalization (CUBIS) Project, which is a collaborative research initiative that offers to Destination Management Organizations an innovative idea of how to connect the members of Generation Y with destination brands using information and communication technologies (ICT). The CUBIS Project aims to create emotional attachment with the brand values and supports the adoption of the brand by young locals and tourists. The CUBIS idea is flexible and highly adaptable to other destinations. The article uses exploratory qualitative research in the form of a case study.

The features of the reproductive biology such as morphology of gametes, larval morphology, larval development and development of gametes of Marenzelleria viridis Type II from the Baltic were summarized. Further reproductive features of Baltic Sea populations are given and the purpose of the review is to account for the successful immigration of M. viridis into the oligohaline areas of the Baltic considered against a background of such variables as population density and structure, salinity, temperature, food availability, oxygen and sulphide levels. Gametogenesis started in spring. Fecundity of animals depended on salinity, temperature, age and size of worms. Mature oocytes contained large cortical alveoli not yet known for polychaetes. Animals spawned in autumn in all years of investigation. The pelagic larvae of M. viridis Type II were found mainly from September to November. Larval development depended on water temperature and lasted about 4 to 12 weeks. Successful larval development from egg to juvenile was not possible below salinities of 5‰, but colonization of oligohaline regions took place by larvae with more than 4 setigers or by swimming juveniles. Reproductive features of M. viridis Type II from the Baltic were compared and discussed with the results of M. viridis Type I populations from the North Sea and North America. The two M. viridis types reproduced at different time, M. viridis Type I reproduced in spring and M. viridis Type II in autumn. Both types showed also differences in larval development, gametal development and sex ratio of mature worms.

Phytoplankton < 20 µm was a principal dietary component of the larvae of Marenzelleria cf. viridis. Maximum ingested particle size increased as animal size increased, reaching a maximum diameter of 80 µm for larvae with 6 to 10 setigers. The larvae started ingesting particulate matter at the 1-setiger stage and were able selectively to ingest phytoplankton and polystyrene particles of various sizes. Larvae in the 6 to 10-setiger size group did not differ from those in the 11 to 17-setiger size group in respect of size selectivity for polystyrene particles. The gut passage time for Chlorella vulgaris was ≥ 20 min. The ingestion rate was limited by food concentrations even at concentrations much higher than those encountered in the natural biotope, saturation being reached at a concentration of 28.5 times 106 cells ml-1 (117.7 mg C l-1. The low maximum filtration rate of only 1.19 µl ind.-1 h-1 indicates that the filtering capacity of the larvae is low. The larvae are still capable of food uptake at 1 °C. Further experiments demonstrated that larval growth and survival were strongly dependent on both food concentration and quality. Larval growth was food-limited under biotope conditions of the Darss–Zingst Boddens and even more so under Baltic Sea conditions. The results indicate that Marenzelleria cf. viridis is a species adapted to eutrophic conditions prevailing in brackish waters.

To find out how the polychaete Marenzelleria cf. viridis could spread successfully into the habitat of the Darss-Zingst Bodden Chain, one important environmental factor for sediment dwelling animals was examined: hydrogen sulphide. To investigate the stress of this environmental factor, hydrogen sulphide was continuously examined in the pore water of the sediment and burrows of M. cf. viridis. Metabolic activity was recorded by direct and indirect calorimetry. Depending on water temperature, organic matter content of the sediment and salinity, the sulphide concentration in the pore water varied between 1.5 and 4.2 mmol l-1 being high during summer and in winter when the sediment and overlying water was ice covered. In microcosm experiments water of M. cf. viridis-burrows showed variations in sulphide between 145 and 210 µmol l-1 but pore water concentration was much higher (6.5 mmol l-1). In the presence of oxygen animals exhibited an accelerated metabolic rate which was met by a fully aerobic metabolism at Po2 of 20 to 7.5 kPa and sulphide concentration of 215–245 µmol l-1. When oxygen is absent the heat production was only slightly elevated (103%) when compared to the anoxic control. The elevated heat production of the animals during sulphide exposure and oxygen may be due to detoxification processes. In this case thiosulphate is formed probably via mitochondrial oxidation and therefore may account for additional ATP-gain.

Summary A gynandromorphous individual of caddisfly Oecetis ochracea (Curtis, 1825) is described and imaged by scanning electron microscopy. The animal was collected from a lake in Northeastern Germany in 2001. The appearances of abnormality were visible at the head, wings and the posterior abdominal segments.

Since its immigration in 1985, the spionid polychaete Marenzelleria viridis (Verrill, 1873) has become a major element of the fauna in the Darss-Zingst Bodden Chain, a tideless estuary-like coastal...

Spermatogenesis in Marenzelleria viridis was studied by ultrastructural investigation. The testes are formed on the greatly ramified nephridial blood vessel and are enveloped by a thin layer of peritoneal cells. The spermatogonia vary in shape, are about 10 μm in diameter and are not linked by intercellular bridges. Pairs or tetrads of spermatocytes connected by intercellular bridges float freely in the coelomic cavity. A complex acrosome is produced by a Golgi complex. The acrosome consists of four to five different structures, forms cisternae and, in the mature spermatozoon, lies deep in an invagination of the nucleus. Two centrioles are also situated in a deep centriolar fossa, the proximal centriole being perpendicular to the distal one. The mature spermatozoon is an ect-aquasperm measuring about 5 μm in length and 2.5 μm in width. The midpiece consists of five spherical mitochondria arranged around the axoneme behind the nucleus. The axoneme is connected to the plasma membrane by a satellite complex. The microtubules of the flagellum are arranged in a typical 9 × 2 + 2 configuration. The spermatogenesis and the sperm morphology of M. viridis were compared with those of other members of the family Spionidae. Copyright © 1996 The Royal Swedish Academy of Sciences. Published by Elsevier Science Ltd.

Summary Oogenesis in Marenzelleria viridis was studied by ultrastructural investigation. The ovaries are formed on the greatly ramified nephridial blood vessels and are enveloped by a thin layer of follicle cells which contain glycogen and a few lipid droplets. The oogonia vary in shape, are about 10 μm in diameter and are not linked by intercellular bridges. Developing previtellogenic and vitellogenic oocytes remain inside the ovary until a late stage of oogenesis. The vitellogenic oocytes contain abundant proteosynthetic rough endoplasmic reticulum and active Golgi complexes. Early developing oocytes are intimately associated with the perivascular cells of blood vessels. There are two possible pathways of uptake of exogenous precursors by the growing oocytes. Low molecular weight precursors may enter the oocytes via the abundant spherical surface granules of the microvilli tips. Endocytotic vesicles along the oolemma indicate the probable uptake of large molecular weight precursors via perivascular cell...

Four apseudomorph tanaidaceans are recorded from benthos of the shelf off Angola and off northern Namibia (SouthWest Africa). Of these, three are new to science, one each in the genera Hemikalliapseudes, Calozodion and Apseudopsis. The genus Hemikalliapseudes now contains four species, all described from West Africa (Angola andMauretania). The new species Hemikalliapseudes sebastiani sp. nov. is separated from other species of this genus byfeatures of several appendages, and the shape of the cephalothorax, pereonites and telson. The genus Calozodion ismainly distributed in the Atlantic and also in the Indian Ocean. Calozodion dominiki sp. nov. is the tenth representativeof the genus and is readily distinguished from all others in that the cheliped propodus of the male has only smallprocesses proximo-ventrally. The new species was widely distributed in the investigation area. Apseudopsis cuanzanus sp. nov. is a new member of this species-rich and widely-distributed genus. It differs from the other species of this genusby a combination of several morphological features, including the absence of a dorsodistal spine on the pereopod 1merus, the lack of anterolateral spines on the pereonites, the shape of rostrum and by the absence of plumose setae on pereopod six basis.

The fauna occurring in waters off South-West Africa is of a remarkable composition and highly diverse due to local waterbodies, flow conditions and abiotic factors. These parameters predominate as a result of the cooperation of a major coastalupwelling system (the Benguela Current Large Marine Ecosystem), the Benguela Current flowing northwards, thesouthward directed Angola Current and the Angola–Benguela Frontal Zone formed in the transition zone of both watercurrents. This area has been insufficiently explored within the last decades and major gaps in biodiversity knowledge existto date. Two expeditions were conducted in 2004/2008, which collected benthic fauna samples. This is a list of brittle starsfound and a comprehensive research study relating to Ophiuroidea in waters off Angola and Namibia. 17 species could beidentified at depths from the littoral zone down to 125 m. The known depth and geographical distributions were extended for several species. Short diagnoses and ecological data are included.

The pelagic larvae of the polychaete Marenzelleria viridis (Verrill, 1873) are newcomers among the meroplankton of the Baltic Sea, where they sometimes achieve an abundance of up to 21x106 ind m-3 near the coast, especially in late autumn and even in winter. Benthos samples were collected in the Darss-Zingst bodden chain from April 1992 to 1993 and used to ascertain the reproductive stages of individuals. Development from fertilized egg to benthic juvenile is described on the basis of field material. Details of the morphology of various pelagic stages and the young benthic worm are presented as drawings and scanning electron microscope photographs. In 1992, development of the gametes started in mid-May. The individuals reached maturity in late September after about 20 wk. The first planktonic stage was the fertilized egg. The larvae have initially one and later two pairs of black eyes and, in the 2nd segment, a ciliated pit. Gastrotrochs are present on the third and thereafter every alternate segment. Neuropodial setae develop once the 7-setiger stage is reached. Palps appear at the 10-setiger stage, and neuropodial bidentate hooks from the 10th to 11th setiger on. Metamorphosis into the juvenile benthic stage takes place at the earliest when the 15-setiger stage has been reached. The reproductive seasons of various populations of M. viridis and the developmental patterns of their larvae are discussed, and differences are compared with relevant findings for the spionids.

Artificial magnetic fields are unavoidable features of offshore wind farms in natural geomagnetic field environments. The movement of the wind over the blades makes them rotate and a connected shaft powers a generator to convert the energy into electricity. This electricity is transmitted by cables over long distances. Operating electric currents always produce magnetic fields, which are essentially dipolar in nature, having a north and a south magnetic pole. The magnetic field lines of a straight current-carrying wire form concentric circles around the wire. The direction of the magnetic field is perpendicular to the wire and defined by the human right-hand rule, where the thumb of the right hand points in the direction of the conventional current and the fingers curl around the wire in the direction of the magnetic field. Direct electric currents (DC) produce static magnetic fields. The impact of a magnetic field is described by the magnetic flux density (B). It is defined as the force acting per unit length on a wire carrying unit current (I). The magnetic flux density around a very long, straight wire can be calculated as

During two sampling campaigns carried out in 2004 and 2008 on the shelf off Angola and northern Namibia (South West Africa), sixteen cumacean species belonging to the families Bodotriidae, Diastylidae and Pseudocumatidae were collected. Two of them are new to science, namely Bodotria fionae and Heterocuma ambrizetensis. Figures are drawn for the new species and additional for seven species, which are partially described up to date. Additionally, an adapted key to the species of Heterocuma is provided. Taxonomic and morphological features were analysed and the findings were compared and discussed with earlier investigations from West Africa.