Brachycythara atlantidea (Knudsen, 1952) and B. beatriceae Mariottini, 2007, both species belonging to the family Mangeliidae, are here moved to the genus Bela Gray, 1847, based on morphological shell features. The new epithets are: Bela atlantidea (Knudsen, 1952) comb. nov. and Bela beatriceae (Mariottini, 2007) comb. nov. The recently described Bela clarae Peňas & Rolán, 2008 is here considered a junior synonym of B. atlantidea according to a comparative scanning electron microscopy analysis of the shells. The distribution of B. atlantidea in the Mediterranean basin is therefore reconsidered including all known records of B. clarae.

This paper reports the first record of the endangered cerianthid Ceriantheomorphe brasiliensis in the State of Paraná, southern Brazil. The observed distribution of the species over Paranaguá Bay is described and some aspects of its conservation are discussed.

Although there are a number of marine organisms located from various parts of the world, little information exists from Iranian coastal waters regarding the distribution of ascidian species. Hence, the present study attempts to describe the presence and distribution of Phallusia nigra from the four different stations along Persian Gulf coastal waters. The current study is the first record of the ascidian P. nigra off the Larak Island, Hengam Island, Qeshm Island and Bandar-e-Lengeh along the Iranian coasts of the Persian Gulf.

A total of twenty-seven species of marine-living coccolithophores were recorded from seawater samples that were collected during two spring cruises along the shelf regions of the Yellow Sea (YS) and the East China Sea (ECS). They were classified into ten families and four orders, with some additional species incertae sedis. Most of these species were heterococcolithophores, and no holococcolithophores were examined from the YS waters. Six species were recorded for the first time from the coastal waters of the China Seas and their morphological characteristics are described and photographically illustrated in this paper. They were Cyrtosphaera lecaliae, Syracosphaera histrica, Syracosphaera marginaporata, Pappomonas cf. sp. type 3, Calyptrolithophora papillifera and Corisphaera strigilis. Three types of Emiliania huxleyi, type A, type B/C and type C, were examined. Species of the genus Syracosphaera, in addition to E. huxleyi and Gephyrocapsa oceanica, frequently occurred at the surveyed sites. The coccolithophore assemblages in the offshore waters of the ECS were characterized by high species diversity—fourteen species in one sample. This finding indicated that the shelf waters adjacent to the Kuroshio path were ideal habitats for living coccolithophores. The variation in taxonomic composition of these algae could be associated with differences in their preferred habitats.

In December 2011 a specimen of the blue tang surgeonfish Acanthurus coeruleus was observed in the waters of Cyprus. As this species typically lives in the tropical western Atlantic Ocean, its presence in the Mediterranean Sea is very likely to be related to human activities. Speculated ways of introduction in the Mediterranean Sea are discussed.

This work reports for the first time cleaning activity by fish and shrimps in Santa Luzia, Cape Verde Archipelago and São Tomé Islands. Three new records of facultative cleaner fish species are presented. Facultative cleaners dominated by Labridae were the most observed cleaner fishes in the two studied islands. Multi-specific cleaning stations were prevalent in Santa Luzia, while cleaner shrimps were more observed interacting in the São Tomé Islands.

Four new records of nudibranchs from Kuwait, one new record for the Arabian Gulf and two rare species are reported together with photographs. A preliminary checklist of nudibranchs occurring in Kuwait is provided, based on current and literature records.

Ethylacetate extract of the gorgonian coral Suberogorgia reticulata was obtained and its effects on the larval settlement by acorn barnacle Balanus (=Amphibalanus) reticulatus and pearl oyster Pinctada martensii and spore germination of green algae Ulva linza and U. lactuca and red alga Gracilaria tenuistipitata was assessed in this study. Results showed that no larval settlement or spore germination occurred at the dose of 100 μg cm−2. Both larval settlement and spore germination were significantly inhibited by the extract at doses of 1 μg cm−2 for B. reticulatus, 0.1 μg cm−2 for U. linza and U. lactuca, and 0.01 μg cm−2 for P. martensii and G. tenuistipitata. It could be concluded that the gorgonian coral S. reticulata may produce bioactive substances with a broad spectrum of activity against a range of marine sessile organisms including macroalgae and invertebrates.

Rimicaris hybisae sp. nov. is described from hydrothermal vent fields on the world's deepest seafloor spreading centre, the Mid-Cayman Spreading Centre (MCSC), Caribbean, at depths of 2300–4960 m. The new species is described and illustrated on the basis of 17 specimens. Brief notes on the distribution and habitat of the new species are provided. Molecular phylogenetic data from mitochondrial COI (460 base pair (bp)), 16S ribosomal RNA (549 bp) and nuclear 18S ribosomal RNA (576 bp) regions is used to complement the description. Morphological variation within R. hybisae sp. nov. and morphological affinities with previously described species are discussed. Based on morphological and molecular evidence, the new species is provisionally assigned to the genus Rimicaris, and differs from all known species in the genus by a distinctive pair of ‘pores' on the posterior lobes of its four-lobed dorsal organ. An emended diagnosis for Rimicaris is provided. Rimicaris hybisae sp. nov. is the first taxon to be described from MCSC vent fields. This record extends the known geographical range of Rimicaris into the Caribbean Sea and constitutes the deepest documented occurrence of alvinocaridid shrimp.

Phymactis papillosa is a rocky shore sea anemone that is commonly found in the Pacific Ocean, from the Gulf of California to Tierra del Fuego, and in the Mar del Plata region, Argentina. The genus Phymactis is closely related to Bunodosoma and, due to character plasticity, a number of misidentifications have occurred. Therefore, the presence of P. papillosa in Argentina has been doubted but the matter had not been investigated in detail. Here we analyse P. papillosa specimens from Argentina and compare them, using molecular and morphological markers, to specimens from the species' type locality. In a phylogenetic analysis using 19 allozyme markers and ribosomal internal transcribed spacers sequences of different sea anemone genera, including all West Atlantic Bunodosoma species, we have found that the specimens from Argentina were genetically divergent from P. papillosa from Chile and closely related to West Atlantic Bunodosoma species. The genetic and morphological analyses indicate that those specimens belong to a new species of the genus Bunodosoma, described here as B. zamponii sp. nov.

Individuals of the sand stargazer Dactyloscopus tridigitatus were collected monthly over a period of one year in an urban-sandy beach in south-eastern Brazil. We sampled 57 males, 64 females, and 6 juveniles, indicating a sex-ratio of approximately 1:1. Total length and weight did not differ significantly between sexes, showing no sexual dimorphism in size. The growth of D. tridigitatus was highly positive allometric and the correlation coefficient was significant for both sexes. Males were observed carrying two egg clumps under each enlarged pectoral fin during most of the year. In contrast, females showed a more restricted reproductive period, concentrated during the austral rainy season. The number of eggs in each clump carried by males did not differ significantly from the number of vitellogenic oocytes of mature females. The number of eggs carried by males was weakly correlated to male total length; however, female fecundity was strongly correlated to female total length. Dactyloscopus tridigitatus consumed a high variety of prey items, including crustaceans, annelids, molluscs, teleosts, insects and eggs. Isopods were the most important component of the diet followed by polychaetes and amphipods. We concluded that promiscuous breeding, paternal care behaviour and invertivorous feeding habits seem to be important traits for the species' success in the studied habitat.

A new species of the genus Dahmsopottekina is described from the Mediterranean Sea. Dahmsopottekina guilvardi sp. nov. was collected from abyssal habitats at a depth range of 2340–2850 m. Like its congeners, the new species has a vermiform habitus, a highly transformed P1 in both sexes and a plough-like rostrum in the female. Dahmsopottekina guilvardi sp. nov. can be distinguished from its congeneric species by the combination of a fused basis and endopodite in P1 of both sexes and the absence of an endopodite in P2–P4 of the female. Dahmsopottekina guilvardi sp. nov. is the second record of a harpacticoid species after its congener D. peruana in which the basis and endopodite of a leg other than the P5, namely the P1, are fused. Furthermore, the new species is the only one among Dahmsopottekina species with a 1-segmented P1 exopodite in the male. Similar to its congeners, D. guilvardi sp. nov. is strongly sexually dimorphic. This is evident through the morphology of most of the cephalic appendages and the reduction of P2–P6 in the female. The results of the present study support the observation that Dahmsopottekina species are sparsely distributed and highly endemic. Nevertheless, our results do not agree with the statement of considerably larger females as the length variability between females is greater than between the two sexes. Despite the morphological characters of the species commensurate with a burrowing mode of life, its presence in sediment traps suggests that D. guilvardi sp. nov. is an active ‘swimmer’.

The variability of shell morphology and relative growth of the invasive pearl oyster Pinctada radiata was studied within and among ten populations from coastal Tunisia using discriminant tests. Therefore, 12 morphological characters were examined and 34 metric and weight ratios were defined. In addition to the classic morphological characters, populations were compared by the thickness of the nacreous layer. Results of Duncan's multiple comparison test showed that the most discriminative ratios were the width of nacreous layer of right valve to the inflation of shell, the hinge line length to the maximum width of shell and the nacre thickness to the maximum width of shell. The analysis of variance revealed an important inter-population morphological variability. Both multidimensional scaling analysis and the squared Mahalanobis distances (D2) of metric ratios divided Tunisian P. radiata populations into four biogeographical groupings: the north coast (La Marsa); harbours (Hammamet, Monastir and Zarzis); the Gulf of Gabès (Sfax, Kerkennah Island, Maharès, Skhira and Djerba) and the intertidal area (Ajim). However, the Kerkennah Island population was discriminated by the squared Mahalanobis distances (D2) of weight ratios in an isolated group suggesting particular trophic conditions in this area. The allometric study revealed high linear correlation between shell morphological characters and differences in allometric growth among P. radiata populations. Unlike the morphological discrimination, allometric differentiation shows no clear geographical distinction. This study revealed that the pearl oyster P. radiata exhibited considerable phenotypic plasticity related to differences of environmental and/or ecological conditions along Tunisian coasts and highlighted the discriminative character of the nacreous layer thickness parameter.

Molecular biological methods including genomic and proteomic approaches hold a specific promise to provide new insights into the stress physiology of corals. However, to fully exploit the power of these techniques, aquarium setups are required that allow biological assays under tightly controlled laboratory conditions. Here, details are provided about the successful development of a closed coral mesocosm at the National Oceanography Centre, Southampton. The system can be operated without access to natural seawater and allows long-term observations and experimental studies of reef corals. The individual experimental tanks allow the corals to be exposed, for example, to different light and/or temperature conditions without the need to disconnect them from the system.

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.

Three species: Oxyonchus orientalis sp. nov., O. sakchalinensis sp. nov., and O. nicholasi sp. nov. (Thoracostomopsidae: Nematoda) are described and illustrated with the aid of light microscopy and laser-scanning microscopy pictures from sediments of Far Eastern Seas (the one former species from the Sea of Japan, Eastern Russia and the two latter species from the Sea of Okhotsk, Sakhalin Island). Generic diagnosis is emended for identification of Oxyonchus. Oxyonchus orientalis sp. nov. has short cephalic sensillae (0.6 cephalic diameters), strongly developed broad mandibular plate with irregular arrangement of numerous small denticles. Oxyonchus sakhalinensis sp. nov. is particularly characterized by the weakly short cephalic capsule, and the rounded thin mandibular plates with 10 denticles. Oxyonchus nicholasi sp. nov. can be differentiated by the structure of the cephalic armament (well developed capsule, fenestrae and incisions), numerous long cervical setae and tail shape. The distribution patterns of the various Oxyonchus species was suggested.

Little is known about the cleaning behaviour of shrimps in comparison to that of cleaner fish, and only recently have cleaner shrimps been shown to remove parasites effectively from coral reef fish. Here we describe patterns of cleaning interactions between Pederson shrimp Ancylomenes pedersoni and fish clients in St Thomas, US Virgin Islands. Clients observed here were members of at least 16 fish families, including three previously unreported client families. Most cleans lasted <20 seconds; surgeonfish were cleaned most frequently, but lizardfish and groupers received the longest cleans. The shrimp formed social groups of varying sizes on individuals of the host sea anemone Bartholomea annulata, which served as the centres of their cleaning stations. The number and duration of cleans per station increased with the number of resident shrimp, however most anemones hosted small groups of fewer than four individuals, while larger groups of up to nine individuals were relatively rare. Some client fish chased away other fish and competitively excluded them from anemone stations. We conclude that these shrimp clean a wide diversity of clients, vary their clean duration with fish identity, and clean more when in large groups. In addition, clients in part control these patterns of interaction by interfering with access to these stations by other clients.

The management scheme of Marine Protected Areas (MPAs) includes monitoring protocols but such activities are not always carried out. This is the case for Golfo San José, a MPA in northern Patagonia, Argentina. It was created in 1975 for the protection of the southern right whale (Eubalaena australis) breeding grounds. Other components of the system, such as dolphin populations have received little attention. This study is the first attempt to estimate sighting rates, group size and overall abundance of a bottlenose dolphin (Tursiops truncatus) population in Golfo San José and adjacent areas after 30 years. An analysis of the seasonal sighting rates indicates that bottlenose dolphins were present in the study area throughout the year but a decline in group size and abundance and major shift in distribution was detected when compared with previous published reports. The settlement of the MPA failed to secure the persistence of the bottlenose dolphin population within its boundaries. Possible explanations for the detected decline are addressed including increased natural mortality, human induced mortality and disturbance, resources depletion and environmental shift.

We provide a review on scientific contributions concerned with Leptocaris (Harpacticoida: Copepoda) that includes the zoogeography, ecology, biology, and morphology of this genus. A tabular key is given to aid in the identification of the ignavus-group. Leptocaris ryukyuensis sp. nov. is included on the basis of specimens collected from Akeijima sandy beach of the Ryukyu Islands in Japan. The new species can be distinguished from its congeners by an abexopodal seta and 3 exopodal setae on A2, a barbed inner seta on the proximal, endopodal segment of female P1 to P3, setae of the caudal ramus (setae I and II are very small, and the basal seta is transformed to a big spine), and modified inner setules of P2 enp-2 and P3 enp-2 in the males. The new species belongs to the ignavus-group established by Kunz (1994) and is the third species of the genus Leptocaris in East Asia.

Little information is available on the maternal–embryonic relationships among sharks. Birdbeak dogfish (Deania calcea) has been described as ovoviviparous, but this term comprises a wide range of forms on how the embryos are nourished including lecithotrophy and matrotrophy. To evaluate the maternal–embryonic relationship in birdbeak dogfish we have analysed chemical features (fatty acid composition and mercury (Hg) levels) and biological characteristics (egg and embryo dry weight variation, uterus characterization). Monounsaturated fatty acids were the dominant fatty acids in eggs while polyunsaturated fatty acids (PUFA) were the dominant fatty acids in both pregnant females and embryos. Significant differences were found among eggs, embryos and pregnant females for all fatty acids groups with the exception of saturated fatty acids for embryos and pregnant females. The principal components analysis revealed that embryos are particularly related to n-6 PUFA and pregnant females with n-3 PUFA. A close relationship exists between the Hg level of pregnant females and the Hg level of their embryos which indicates that there is a transfer of mercury from maternal sources. The comparison of the mean dry weight between eggs and embryos showed a gain of 3.8% obtained in the embryos. Histological sections of the uteri of pregnant females showed a high level of both superficial and inner vascularization in the uterine villi as well as the presence of secretor cells. Until now, the importance of this species maternal contribution and interference for the embryos development has never been documented. However, the biological and chemical results observed in the present work show that there is a matrotrophic strategy for the birdbeak dogfish.