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The NaGISA project (Natural Geography Ιn Shore Areas) is a global initiative within the framework of the Census of Marine Life. The Mediterranean Sea has joined with 4 stations, 2 in Italy and 2 on the island of Crete, Greece. Two different sites were sampled during two consecutive years (2007 and 2008) by means of SCUBA diving. On the basis of the evidence offered by the collected material from the hard substrates of Crete, and the literature mined datasets concerning the molluscan assemblages, two main issues are investigated: (a) is the molluscan fauna sampled in the two NaGISA sites representative of the regional Mediterranean one? and (b), is the molluscan fauna sampled from the two sites randomly assembled from the regional species pool across different spatial scales? Although a strong tendency of the local molluskan composition to be randomly sampled from the regional pools at all scales, it is not possible to demonstrate with a degree of certainty whether their observed local diversity is independent of local and regional processes or if it is determined by a combination of the two acting either in concert or antagonistically. [ABSTRACT FROM AUTHOR]

The Antarctic sublittoral is one of the most demanding habitat for polar bottom-dwelling organisms, as the disturbance of this zone is highly intense. Rapid changes in the marine environment, such as increases in atmosphere and surface water temperatures, can cause dramatic changes in biodiversity, especially in glacial fjords affected by heavy melt water inputs from the retreating glaciers. In such areas, rocks are often an important support for local diversity, providing habitats for a number of encrusting organisms. Thus, understanding the patterns of diversity of shallow rock encrusting fauna and factors controlling it are particularly important. The structure and diversity patterns of rock encrusting fauna were examined from four ecologically contrasting sites in the shallow sublittoral (6–20 m) of Admiralty Bay (King George Island). The results revealed a rich and abundant encrusting community with bryozoans and polychaetes outcompeting representatives of other fauna such as foraminifera and porifera. Spatial variability in species composition, as well as biological parameters, revealed the trend of encrusting assemblages declining towards the inner fjord areas - strongly affected by high sediment input (species richness: 13.3 ± 1.2, and abundance: 68,932.99 ± 11,915.98 individuals m −2  ± standard error). In contrast, at sites more open to the central basin, a peak of biological parameters was observed (24.8 ± 1.4 and 297,360.9 ± 30,314.72, respectively). We suggest that increased sedimentation was the major factor structuring the encrusting assemblages in Ezcurra Inlet, masking the influence of other parameters, such as food and light availability, which are important for the distribution of epifauna. Thus, if the increasing intensity of glacial processes will continue in the upcoming years, the diversity of the encrusting fauna in the shallow sublittoral could dramatically decrease. [ABSTRACT FROM AUTHOR]

Surveys of species diversity in sublittoral waters along the coasts of the Cape Peninsula on the Atlantic coast of South Africa yielded three species of Mysidopsis G.O. Sars, 1864. A new species, M. abbreviata   n. sp. is described, a supplementary description is given for M. similis (Zimmer, 1912), and the female of M. zsilaveczi   Wittmann & Griffiths, 2014 is described for the first time. The new species is characterized, among other characters, by a transversely shortened rostrum. Field observations of M. zsilaveczi and M. abbreviata   n. sp. showed the greatest intraspecific diversity of colour patterns ever documented for mysids. Stomach contents, together with differences in the armature of perioral mouthparts and in the foregut, suggest that all three species are specialized predators, mainly of crustaceans. An updated key to the species of Mysidopsis in southern Africa is given. [ABSTRACT FROM AUTHOR]

Coastal areas commonly consist of an environment of intense economic uses and are thus exposed to conflicts between anthropogenic activities and biodiversity. While several approaches of nature protection have been applied to the terrestrial domain, aquatic biotopes frequently still lack a good ecological state as required by EU policies (WFD and MSFD). For numerous years, the underwater world has been considered as one sphere and was neglected in the development of distinctive concepts of conservation for its variety of biotopes. This paper’s objective is the enhancement of ecological connectivity within the study area through the design of benthic wildlife corridors and a consequent sublittoral biotope network. A step-by-step approach is presented for the optimization of ecological potential in heavily modified coastal water bodies, using Kiel Fjord (Western Baltic Sea) as a case study. The procedure for the development of wildlife corridors includes defining and mapping of existing biotope types, the identification of key species for each biotope type and delineating their mobility range, the reconstruction of near-natural / pre-industrial conditions and deriving the protection priorities by comparing past with current / modified conditions. By harmonizing these scientific insights with the local land use of human society, proposals for biotope restoration and improvements can be made. In Kiel Fjord, compensation measures, obligatory for human interventions, such as construction work in the marine environment in this case, have been implemented and present an opportunity to enhance the connectivity of biotopes, thus creating wildlife corridors for their inhabitants. The composition of benthic wildlife corridors, forming a sublittoral biotope network in accordance with the present anthropogenic uses, holds potential for implementation in comparably altered coastal water bodies and integration into national and international frameworks, in anticipation of its functionality. [ABSTRACT FROM AUTHOR]

The article focuses on Squilla mantis species of spottail mantis (S. mantis) shrimp which are found in Ria Formosa Lagoon in southern Portugal. Topics discussed include sublittoral areas inhabited by S. mantis, commercial exploitation of stomatopod species which are found in the Mediterranean sea, and measurement done of specimen of S. mantis with a digital calliper and photography with a digital camera.

We establish baseline knowledge of abundance, diversity and multivariate structure of macrobenthos from shallow sublitoral soft bottoms in the North Portuguese coast and elucidate main environmental factors that shape their spatial patterns. In this area distribution of soft bottoms is patchy, surrounded by boulders and rocky substrates. This particular landscape and the lack of significant anthropogenic disturbances are values for the conservation of this habitat. Sediment and physicochemical properties of the water column were studied to provide models for each studied macrobenthic variable. Our models highlighted that most of variation (59%–72%) in macrobenthic spatial patterns was explained by the studied environmental variables. Sedimentary variables were more relevant that those of the water column. Therefore, disturbances affecting sedimentary environment could cause dramatic changes in macrobenthic assemblages because of the limited availability of soft bottoms in the area. In this way, results are useful to adopt right management and conservation strategies. [ABSTRACT FROM AUTHOR]

Leiochrides yokjidoensis sp. n., collected from the sublittoral muddy bottom in southern Korea, is described as a new species. The taxonomic status of the monospecific genus Pseudomastus has been a subject of controversy for many years, as its characteristics overlap those given in recent generic definitions of Leiochrides. The results of a comprehensive review and comparison regarding the two genera, based on previous records showed minor differences. In this study, a detailed description of L. yokjidoensis sp. n. is given and a comparison with closely related species is tabulated and discussed. The taxonomic status of Pseudomastus is discussed and the genus placed in synonymy with Leiochrides. [ABSTRACT FROM AUTHOR]

The calcareous nannoplankton was established for the first time in Upper Volgian deposits of the Loino Section (Kirov oblast). Here, single coccolites of representatives of genus Watznaueria of wide stratigraphic and geographic distributions dominate. Representatives of genus Zuegrhabdotus are less common, whereas species of genus Polypodorhabdus are rare. The taxonomic composition of the calcareous nannoplankton assemblage does not allow us to distinguish the nannoplankton zone in the Loino Section, but it gives us an idea about its distribution at the Volgian Stage in the Russian Plate. As corresponding microfauna, foraminifers, assigned to the Lenticulina infravolgaensis-Saracenaria pravoslavlevi Zone, and ostracods were identified to substantiate the age of host deposits. The ostracod assemblage is assigned to the Macrodentina (Polydentina) subtriangularis Beds established on the Volga River left bank in deposits corresponding to the ammonite zones Panderi and Virgatus assigned to the middle Volgian substage. On the basis of ostracods, the warm-water well-aerating environment of the upper sublittoral (as deep as 50 m) was reconstructed. [ABSTRACT FROM AUTHOR]

The role of labile organic material and macrofaunal activity in benthic respiration and nutrient regeneration have been tested in sublittoral fine sand sediments from the Gulf of Valencia (northwestern Mediterranean Sea). Three experimental setups were made using benthic chambers. One experiment was performed in-situ through the annual cycle in a well-sorted fine sand community. The remaining experiments were carried out with mesocosms under laboratory conditions: one with different concentrations of organic enrichment (mussel meat and concentrated diatoms culture), and the other adding two different densities of the endofaunal bivalve Spisula subtruncata. Biochemical variables in surface sediment and changes in oxygen consumption and nutrient fluxes throughout incubation period were studied in each experiment. In the in situ incubations, dissolved oxygen (DO) fluxes showed a strong correlation with sedimentary biopolymeric fraction of organic carbon. Organic enrichment in the laboratory experiments was responsible for increased benthic respiration. However, sediment response (expressed as DO uptake and dissolved inorganic nitrogen-DIN-release) between oligotrophic and eutrophic conditions was more intense than between eutrophic and hypertrophic conditions. S. subtruncata abundances close to 400 and 850 ind m also intensified benthic metabolism. DO uptake and DIN production in mesocosms with added fauna were between 60 and 75 % and 65-100 % higher than in the control treatment respectively. The results of these three experiments suggest that the macrobenthic community may increase the benthic respiration by roughly a factor of two in these bottoms, where S. subtruncata is one of the dominant species. Both organic enrichment and macrobenthic community in general, and S. subtruncata in particular, did not seem to have a relevant role in P and Si cycles in these sediments. [ABSTRACT FROM AUTHOR]

The first interaction of water column-derived organic matter with benthic microbial communities takes place in surface sediments which are acting as biological filters catalyzing central steps of elemental cycling. Here we analyzed the bacterial diversity and community structure of sediment top layers at seven sites in the North Sea where sediment properties ranged from coarse-grained and highly permeable to fine-grained and impermeable. Bacterial communities in surface sediments were richer, more even and significantly different from communities in bottom waters as revealed by Illumina tag sequencing of 16S rRNA genes. Sediment permeability had a clear influence on community composition which was confirmed by CARD-FISH. Sulfate-reducing Desulfobacteraceae (2-5% of total cells), Flavobacteriaceae (3-5%) were more abundant in impermeable than in highly permeable sediments where acidobacterial Sva0725 dominated (11-15%). Myxobacterial Sandaracinaceae were most abundant in medium permeable sediments (3-7%). Woeseiaceae/JTB255 and Planctomycetes were major groups in all sediments (4-6%, 8-22%). Planctomycetes were highly diverse and branched throughout the phylum. We propose Planctomycetes as key bacteria for degradation of high molecular weight compounds and recalcitrant material entering surface sediments from the water column. Benthic Flavobacteriaceae likely have restricted capabilities for macromolecule degradation and might profit with Sandaracinaceae and Acidobacteria from low molecular weight compounds. [ABSTRACT FROM AUTHOR]

Cappucci, S.; Valentini, E.; Del Monte, M.; Paci, M.; Filipponi, F., and Taramelli, A., 2017. Detection of natural and anthropic features on small islands. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue No. 77, pp. 73-87. Coconut Creek (Florida), ISSN 0749-0208. Mapping the distribution of seabed habitats, and estimating the spatial distribution of features and biocenosis over land and the seafloor, is particularly important for the analysis of human impacts. The present paper uses an innovative image analysis method that integrates different data sources from airborne remote sensing and in situ measurements for different features, allowing the detection of ecological 'tipping points' both in emerged and submerged coastal environments. Results show that it is possible to differentiate between the respective roles of: first, the internal variability of the natural morphological system and second, of external forcing factors. The final evidence, however, identifies a clear signature of external forcing, but whether of anthropogenic or natural origin, is unclear. The spatial pattern of the response to anthropogenic forcing may be indistinguishable from patterns of natural variability. It is argued that this novel approach to define tipping points following anthropogenic impacts could be most valuable in the management of natural resources and the economic development of coastal areas worldwide. [ABSTRACT FROM AUTHOR]

The macrozoobenthos of Cahul Lake (one of the largest in Ukrainian Danube basin) has been studied. We collected 256 samples at 12 littoral and sublittoral stations within 2006-2012. Some 95 species and subspecies were found, namely: Spongia - 1 species, Turbellaria - 2, Annelida - 17, Bryozoa - 1, Crustacea - 19, Insecta - 35, Gastropoda - 15 and Bivalvia - 5 species, among them 15 previously unregistered species were found. We discovered that the overall number of species increased downstream. Seasonal dynamics of species composition is poorly expressed. The maximum number of macrozoobenthos on the littoral was recorded in spring, maximal biomass - in summer; Maximum sublittoral abundance and biomass of macrozoobenthos were recorded in the summer. [ABSTRACT FROM AUTHOR]

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There is growing awareness that to improve the understanding of the biological control of silicon (Si) cycling in the oceans, the biogeochemical models need to incorporate Si users other than diatoms. In the last decades, siliceous sponges are coming into sight as important Si users, but the scarce quantitative information on how they use Si is hindering the assessment of their role. We are here investigating Si consumption kinetics in two demosponge species ( Tethya citrina and Hymeniacidon perlevis) that have contrasting biological features while inhabiting at the same sublittoral habitat. In laboratory experiments, we have determined that both species share some common traits when incorporating Si from seawater: (1) saturable Michaelis-Menten kinetics; (2) maximum velocity of Si consumption occurring at high silicic acid (DSi) concentrations (∼150 μM) that are not available in shallow waters of the modern oceans; (3) the ability to increase consumption rates rapidly and predictably in response to increasing DSi availability; and (4) half-saturation constants that indicate an affinity for DSi lower than those of diatom systems. Across the four sponge species investigated to date, the affinity for DSi varies about 4.5 times. Our results also suggest that at least part of that between-species variability reflects the skeletonization level of the species. Within a given species, there are also between-individual differences in the DSi demand, which appear to reflect the particular physiological condition of each individual (i.e., body size, reproductive vs. non-reproductive stage). [ABSTRACT FROM AUTHOR]

Coral mortality may result in macroalgal proliferation or a phase shift into an alga-dominated state. Subtidal, high-latitude western Indian Ocean coral communities at Sodwana Bay on the KwaZulu-Natal coast, South Africa, have experienced some mortality because of warm-water anomalies, storms and other causes, but the response of the macroalgae is unknown. We investigated the abundance and diversity of benthic algae on different hard natural substrata (dead digitate, brain and plate corals and beach rock) on Two-Mile Reef, Sodwana Bay. We also compared algal communities colonising ceramic, marble and pretreated ceramic tiles placed on the reef for six months. We identified 95 algae (14 Chlorophyta, 11 Phaeophyceae, 69 Rhodophyta and one cyanobacterium). Assemblages on natural and artificial substrata were dominated by the brown algaLobophora variegata(Lamouroux) Womersley ex Oliveira and non-geniculate corallines (Rhodophyta, Corallinaceae). Cluster and ordination analyses revealed that the algae showed no affinity for particular substrata, whether natural or artificial. Algal cover was occasionally higher on rougher tiles and crustose corallines were significantly more abundant on marble than ceramic tiles. Two-Mile Reef had 23.1% dead and 48.4% live scleractinian coral cover, where dead corals were colonised indiscriminately by many small algal species, but there was no evidence of algal proliferation. The results provide a baseline for monitoring this high-latitude reef system. [ABSTRACT FROM AUTHOR]

Commercially harvested since ancient times, the highly valuable red coral Corallium rubrum (Linnaeus, 1758) is an octocoral endemic to the Mediterranean Sea and adjacent Eastern Atlantic Ocean, where it occurs on rocky bottoms over a wide bathymetric range. Current knowledge is restricted to its shallow populations (15-50 m depth), with comparably little attention given to the deeper populations (50-200 m) that are nowadays the main target of exploitation. In this study, red coral distribution and population structure were assessed in three historically exploited areas (Amalfi, Ischia Island and Elba Island) in the Tyrrhenian Sea (Western Mediterranean Sea) between 50 and 130 m depth by means of ROV during a cruise carried out in the summer of 2010. Red coral populations showed a maximum patch frequency of 0.20 ± 0.04 SD patches·m−1 and a density ranging between 28 and 204 colonies·m−2, with a fairly continuous bathymetric distribution. The highest red coral densities in the investigated areas were found on cliffs and boulders mainly exposed to the east, at the greatest depth, and characterized by medium percentage sediment cover. The study populations contained a high percentage (46% on average) of harvestable colonies (>7 mm basal diameter). Moreover, some colonies with fifth-order branches were also observed, highlighting the probable older age of some components of these populations. The Ischia population showed the highest colony occupancy, density and size, suggesting a better conservation status than the populations at the other study locations. These results indicate that deep dwelling red coral populations in non-stressed or less-harvested areas may diverge from the inverse size-density relationship previously observed in red coral populations with increasing depth. [ABSTRACT FROM AUTHOR]

Cinquante-huit espèces appartenant au genre Mastogloia ont été répertoriées dans des prélèvements effectués dans la zone infralittorale (-1,5 à - 7 mètres sous le zéro des cartes) sur la côte d'une île située au Nord-Est de l'Océan Atlantique (Île de Groix). La majorité de ces espèces est présente dans les régions tropicales et subtropicales. Cette étude apporte de nouvelles informations sur la distribution géographique de ces espèces. En outre, la morphologie de quatre espèces non identifiées est décrite en microscopie photonique. Fifty eight Mastogloia species were found in samples collected in the sublittoral zone (1.5 - 7 m charted depth) on the coast of a North-Eastern Atlantic island (Groix Island). Most of them are usually present in tropical and subtropical waters. The objective of this study was to provide new information on the biogeography of the genus Mastogloia. In addition, the morphology of four undetermined taxa was described using LM. [ABSTRACT FROM AUTHOR]

1. In the planning of marine protected areas for the conservation of coral reef systems, it is important to be able to distinguish between certain bioregions, i.e. regions with distinct species assemblages. This was done off western Halmahera (Moluccas, Indonesia), where three such bioregions were distinguished based on species inventories of 41 coral reef sites. 2. The relative value of species belonging to different trophic groups was examined with regard to their possible role as indicators for these three regions. The study focused on ascidians (Ascidiacea), macroalgae, mushroom corals (Fungiidae), and a selection of coral-associated gastropods (Epitoniidae and Coralliophilidae). 3. The best results for the detection of bioregions were obtained when datasets of all four trophic groups were pooled. When comparing the taxa and their indicator values, ascidians were the most suitable, followed by macroalgae, corals and gastropods with 98, 83, 71 and 66 % certainties, respectively. The occurrence of 17 species correlated strongly with the bioregions, which therefore were identified as potential indicator species consisting of 13 ascidians, three macroalgae, and one mushroom coral. These data suggest that ascidians have a significant value as indicators to evaluate bioregion boundaries. 4. Water quality measurements indicated that salinity and turbidity could be responsible for at least part of the differences between the species assemblages in the three bioregions. [ABSTRACT FROM AUTHOR]

Changes in the seasonal dynamics of Mediterranean macroalgal-dominated assemblages from the upper sublittoral zone are described along a gradient of sewage pollution. Algal coverage and composition were measured for more than one year at approximately monthly intervals. Nutrients concentrations (nitrites, nitrates, ammonia and phosphates) showed different seasonal patterns depending on the distance to the pollution focus. Ulva -dominated assemblages appearing close to the sewage outfall showed maximal coverage during early spring and started to decrease in May. Corallina -dominated assemblages - replacing ulvacean algae at intermediate levels of pollution - followed the same pattern, peaking in March and decreasing in May. In contrast, Cystoseira -dominated assemblages, present at sites with low or no influence of sewage, increased coverage in May and continued with high coverage until the end of summer. Neither ephemeral algae ( Ulva spp.), nor stress-tolerant algae ( Corallina elongata ), nor canopy-forming algae ( Cystoseira spp.) have a seasonal growth cycle governed by eutrophication. Results demonstrate also that the period from May to July is the best time of the year for Water Framework Directive (WFD) monitoring purposes as less variability is observed within the assemblages. [ABSTRACT FROM AUTHOR]

Numerous trace fossils are described from the Late Miocene sediments of the Bzenec Formation exposed at the Gbely section (the Vienna Basin, Slovakia). During deposition of the sediments the area was part of the large, long-lived brackish to freshwater Lake Pannon. Most of the trace fossils are attributed herein to Egbellichnus jordidegiberti igen et ispec. nov. and are interpreted as burrows produced by decapod crustaceans, specifically by a ghost shrimp of the family Callianassidae. This interpretation is based on two independent lines of evidence: environmental requirements of large bioturbators and the burrow morphology itself. The new ichnotaxon is distinguished from other related ichnotaxa by a combination of typically inclined (roughly at an angle of 45°) cylindrical burrows, absence of lining, and tunnels making loops or bends at approximately right angles. The burrow systems at Gbely document the survival of ghost shrimp long after the closure of all seaways and the origin of Lake Pannon. As today, no ghost shrimp are known from long-lived brackish lakes. Egbellichnus from Gbely is the only, although indirect, record of ghost shrimp from a brackish lake environment reported so far. [ABSTRACT FROM AUTHOR]

An evaluation of all species of the genusHanleyashowed that they only inhabit the Atlantic Ocean, occurring from off Brazil (25°44′S) to the Barents Sea (74°27′N). The majority of records refer toH. nagelfarwhich ranges from 9°03′8′′N to 74°27′N in coastal waters of North America, Europe and Africa. There are six Recent species ofHanleya:H. tropicalisDall, 1881,H. brachyplaxJardim and Simone, 2010b,H. harasewychisp. nov,H. mediterraneasp. nov,H. hanleyi(Bean in Thorpe, 1844) andH. nagelfar(Lovén, 1846). The phylogenetic relationship ofH. hanleyiandH. nagelfarhas long been questioned. New data on age variability ofHanleya nagelfarare provided.Hanleya hanleyiis the only species of the genus that also occurs in the intertidal zone. All other members ofHanleyainhabit mainly bathyal or sublittoral depths:H. nagelfar(28–1680 m),H. tropicalis(230 m),H. brachyplax(250–408 m),H. harasewychi(73–115 m),H. mediterranea(50–200 m). http://zoobank.org/urn:lsid:zoobank.org:pub:CB8027AC-6755-4F44-9A02-D5C539D84D1F [ABSTRACT FROM AUTHOR]

A new species of marine interstitial wormshrimp, Ingolfiella maldivensis, is described from coral sand on the inner and outer reef off Magoodhoo island, Faafu atoll, Maldives. Six females were found and compared to other species from the Maldives and those bordering the Indian Ocean and beyond. Morphological resemblance ties it to a species from the Caribbean island of Curaçao. Both species are found in shallow sublittoral interstitial spaces. [ABSTRACT FROM AUTHOR]

Gorgonians are widespread sub-littoral benthic suspension feeders in the world oceans. However, data on their trophic ecology and role in benthic-pelagic coupling and biogeochemical cycles remain limited. This study assesses the trophic ecology of Leptogorgia virgulata in the Skidaway River estuary, USA (31.9896N, 81.0242W) by analysing carbon and nitrogen isotopic signatures of its soft tissue and different-sized fractions of particulate organic matter (POM) in its environment. Samples were taken in 5 April, 2 August, and 15 October 2012 and 11 January 2013. Results support a distinct temporal shift in the diet of L. virgulata from the POM fraction <10 µm (i.e. pico- and nanoplankton) to the 10-63-µm fraction (i.e. microplankton). This trophic regime is likely associated with the natural abundance of prey items within these size classes, thus suggesting that L. virgulata may be an opportunistic feeder, and seasonal shifts in food availability in the water column affect its diet. As such small prey items affect the bioenergetics of L. virgulata, it is important to understand the implications of changes in food availability associated with environmental drivers on the physiology and population dynamics of this dominant species in the western Atlantic Ocean. [ABSTRACT FROM AUTHOR]

Ecological succession has been scarcely investigated on sublittoral rocky cliffs. The few relevant studies deal with the structure of the developing community and are limited to higher taxa or sessile forms. The objective of the present study was to examine succession patterns on algal-dominated rocky cliffs both at the structural (species composition) and functional (feeding guild composition) level, using Polychaeta, a dominant taxon in this marine habitat, as a reference group. Cement panels were seasonally installed on the rocky substratum (25-30 m depth) and sampled every 3 months over a 1-year period. Twenty-nine polychaete species were recorded, previously reported from the surrounding benthic community, and classified into eight feeding guilds. Most species were assigned as sessile filter-feeders; this guild dominated in abundance and biomass. A strong effect of the length of immersion and of the seasonal onset of succession on the developed communities was assessed: species composition analyses suggested convergence into a similar organization as succession proceeds, whereas the impact of starting season on succession was stronger when analysing feeding guilds. In both cases succession was faster on panels installed in winter. The main emerging patterns were in agreement with relevant surveys of the entire benthic fauna, thus supporting the efficacy of polychaetes as a surrogate group for studying ecological succession in the benthic marine environment. [ABSTRACT FROM AUTHOR]

Intertidal fish assemblages are thought to respond to tidal and diel rhythms although the assumption that these patterns are stable over long time scales (>1 year) is largely untested. Testing the validity of this assumption is necessary to assess whether short-term temporal patterns, once established, can be extrapolated over time and give a better understanding of the temporal dynamics of fish assemblages in coastal habitats. Here, we compare the fish assemblage structure from two intertidal mangrove creeks in North Brazil (Bragança Peninsula, Caeté estuary) sampled with the same sampling methodology (block nets), effort (two lunar cycles) and design (accounting for the combination of tidal and diel cycle) in the rainy seasons of 1999 and 2012 to evaluate the persistence, stability and recurrence of short-term patterns in the fish community organization. The interaction of tidal and diel cycles (inundations at spring tide-night, spring tide-day, neap tide-night, neap tide-day), found to be stable after 13 years, resulted in recurrent and stable intertidal mangrove fish assemblage compositions. The intertidal mangrove creek fish assemblage consisted of a persistent number of dominant species (seven). However, there were notable changes in fish catch mass, abundance and species dominance between 1999 and 2012. The most severe drought in North Brazil in 30 years, linked to lower precipitation and river runoff in the rainy season of 2012, may have resulted in (1) lower abundance of small juveniles of several dominant species in this assemblage (especially Ariidae – Cathorops agassizii and Sciades herzbergii ) and (2) increased dominance of large-sized specimens of the tetraodontid Colomesus psittacus . Our findings highlight: (1) the overriding importance and stability of the interactive pulse of the tidal and diel cycles in determining short-term temporal patterns in intertidal mangrove fish assemblages in neotropical macrotidal estuaries despite the occurrence of extreme events (i.e. major decrease in rainfall) and (2) the large-scale influence that these extreme events can exert on recruitment processes in tropical estuarine fish assemblages. [ABSTRACT FROM AUTHOR]

Understanding individual dispersion from offshore natal areas to coastal nurseries during pelagic larval life is especially important for the sustainable management of exploited marine fish species. For several years, the hatching period, the larval life duration, the average growth rate and the otolith chemical composition (δ 13 C, δ 18 O, Sr:Ca and Ba:Ca) during the larval life were studied for young of the year (YOY) of sole collected in three main nurseries of the Gulf of Lions (GoL) (Thau, Mauguio and Berre). We investigated the spatial variation in the origin of the sole larvae which colonised the nurseries around the GoL, and whether temporal differences in environmental conditions during this life stage affected growth and larval life duration. The hatching period ranges from October to March, depending on year and site. Average ages at metamorphosis varied between 43 and 50 days, with the lowest and highest values consistently found for Mauguio and Berre, respectively. Otolith growth rates ranged between 2.7 and 3.2 μm d −1 , with the lowest values in Thau and Mauguio and the highest in Berre. Otolith chemical composition during the larval life also varied, suggesting contrasted larval environmental histories in YOY among nurseries. In fishes from Berre and Mauguio, larval life was more influenced by the Rhône River, showing consistently higher larval Ba:Ca ratios (10/23 μmol mol −1 ) and lower δ 13 C (−6.5/−6.1‰) and δ 18 O values (−1.6/0.1‰) than for Thau (with Ba:Ca ratios < 8 μmol mol −1 , δ 13 C ∼−2.3‰ and δ 18 O ∼1.5‰). Differences in larval otolith composition were observed for 2004, with higher Ba:Ca and lower δ 13 C and δ 18 O values than in the two other years. These differences were explained by changes in composition and chemical signatures of water masses after an exceptional flooding event of the Rhône River in late 2003. [ABSTRACT FROM AUTHOR]

A new species of marine Gastrotricha,Urodasys poculostylissp. nov. (Macrodasyida: Macrodasyidae), is described from the sublittoral sediments of Capron Shoal, Florida. The new species is a simultaneous hermaphrodite with a single left testis, a stylet bulb and a frontal organ. The stylet bulb bears a cup-shaped sclerotic stylet up to 20 µm long. Several specimens possessed a large spermatophore within the frontal organ.Urodasys poculostylissp. nov. can be further distinguished by the presence of three pairs of anterior adhesive tubes distributed in two rows, 14–17 pairs of lateral adhesive tubes with staggered insertions, 5–7 pairs of ventrolateral adhesive tubes, 12–15 pairs of dorsolateral adhesive tubes and two dorsal adhesive tubes. [ABSTRACT FROM AUTHOR]

This is a first account on amphipods from Marian Cove in Maxwell Bay, near the King Sejong Station, King George Island, the Antarctic. We have conducted a survey in 14 localities in the shallow sublittoral zone. A total of 22 amphipod species belonging to 12 families were identified. Six of these species were new for the whole Maxwell Bay. Our findings increase the amphipod fauna of Maxwell Bay from 55 to 61 species. The dominant species in the shallow sublittoral zone of Marian Cove were: Cheirimedon femoratus and Gondogeneia antarctica, followed by Bovallia gigantea, Orchomenella cf. ultima, Paradexamine fissicauda, Prostebbingia brevicornis, Pariphimedia integricauda, and Jassa wandeli. [ABSTRACT FROM AUTHOR]

Abstract: Several species of benthic macro and meio-invertebrates actively emerge from the seabed to the water column during the night. Such diel vertical migrations have important consequences for benthic–pelagic coupling, dispersal, connectivity and recovery after disturbance of benthic assemblages. However, this process has never been studied in the coast of the Humboldt Current ecosystem. Herein we examined the relationship between the emerging assemblage and moon phases (and co-variables) and the timing of emergence during the day/night cycle, in a sublittoral soft-bottom habitat. Sampling using emergence traps was conducted at 7m depth in the zone of Bolsico, a sheltered cove with low bottom hydrodynamics in northern Chile. Multivariable analysis showed that changes in the dissimilarity of the emerging assemblage were related to each moon phase. The percentage of moon illumination, bottom illumination and tide amplitude explained most of the variation of the emerging assemblage. Species showed differential responses to each moon phase; some were abundant at intermediate phases (e.g., harpacticoids), or peaked at full moon (e.g. ostracods) and others such as mysids emerged in equal abundances at all moon phases. The timing of assemblage emergence followed a consecutive sequence through the night/day period. Most of the studies dealing with the emergence processes have described species-specific responses. Our research shows that the examination at assemblage level may reveal new and distinct patterns of emergence in sublittoral soft-bottom habitats. [Copyright &y& Elsevier]

The article presents a study that described the macrofaunal assemblage that performs diel vertical migrations for the first time in a shallow, sublittoral soft-bottom habitat in northern Chile. The researchers discussed a short-term experiment using traps for collecting emerging invertebrates in a sublittoral site. They reported 17 taxa of identified benthic invertebrates, principally composed of peracarids, copepods and ostracods.

In the present paper, three dictyotalean brown algae ( Dictyopteris lucida, Dictyota cyanoloma, and Padina pavonicoides) are reported for the first time from Turkey. D. cyanoloma and P. pavonicoides are also reported for the first time from the eastern Mediterranean Sea. The species were collected in the sublittoral zone near İzmir (Aegean coast of Turkey). The data concerning the habitat and morphology of these species are presented. [ABSTRACT FROM AUTHOR]

The average pH of surface oceans has decreased by 0.1 unit since industrialization and is expected to decrease by another 0.3–0.7 units before the year 2300 due to the absorption of anthropogenic CO2. This human-caused pH change is posing serious threats and challenges to the Pacific oyster (Crassostrea gigas), especially to their larval stages. Our knowledge of the effect of reduced pH on C. gigas larvae presently relies presumptively on four short-term (<4 days) survival and growth studies. Using multiple physiological measurements and life stages, the effects of long-term (40 days) exposure to pH 8.1, 7.7 and 7.4 on larval shell growth, metamorphosis, respiration and filtration rates at the time of metamorphosis, along with the juvenile shell growth and structure of the C. gigas, were examined in this study. The mean survival and growth rates were not affected by pH. The metabolic, feeding and metamorphosis rates of pediveliger larvae were similar, between pH 8.1 and 7.7. The pediveligers at pH 7.4 showed reduced weight-specific metabolic and filtration rates, yet were able to sustain a more rapid post-settlement growth rate. However, no evidence suggested that low pH treatments resulted in alterations to the shell ultrastructures (SEM images) or elemental compositions (i.e., Mg/Ca and Sr/Ca ratios). Thus, larval and post-larval forms of the C. gigas in the Yellow Sea are probably resistant to elevated CO2 and decreased near-future pH scenarios. The pre-adapted ability to resist a wide range of decreased pH may provide C. gigas with the necessary tolerance to withstand rapid pH changes over the coming century. [ABSTRACT FROM AUTHOR]

Abstract: Although large crabs are recognized as important sediment disturbers influencing the structure of benthic communities, the role of dominant predatory crabs in soft-bottom habitats along the Humboldt Current Ecosystem, remains largely unknown. A field study was conducted, hypothesizing that the digging activity of these predators disturbs the habitat thereby leading to a reduction in individual abundance, biomass and species richness; these changes result in a modified structure of macrobenthic communities. A directed sampling (crab pits vs. reference areas) showed significant reductions in total abundances in pits compared to reference areas, but no differences were observed in taxonomic richness or benthic biomass. Short-term cage experiment showed significant decreases in total abundance and biomass of macroinvertebrates in predator inclusion treatments compared to exclusions and controls. In consequence, our results confirmed that burrowing activities and the generation of small disturbed sediment patches influence the community structure. These results highlight the importance of large cancrid crabs in soft-bottom habitats, where their modification of the physical configuration of the sediment affects community structure over small spatial scales. Crabs are thus an important source of spatial heterogeneity of the sea-floor landscape. This ecological role must be considered in management strategies of the extensive artisanal fishery for these crabs, as current evidence is showing increasing populations of intermediate predators (like cancrid crabs) in many benthic habitats in response to the depletion of top predators. [Copyright &y& Elsevier]

Abstract: We examined whether two decades of rising sea surface temperatures have resulted in significant changes in the benthic community and frequency of occurrence of Northern and Southern species in three areas of Northern Ireland, using visual census data collected by SCUBA surveys undertaken during two periods: pre-1986 and post-2006. We found little evidence to suggest that rising sea surface temperatures have contributed to the changes in benthic assemblage structure between the pre-1986 and post-2006 surveys. However, there were slight but not significant declines in extreme Northern species at Rathlin Island, and increases in the mean number and frequency of occurrence of extreme Southern species in all three areas. There were also substantial declines in the spatial presence of 7 extreme Northern species and notable increases in distribution of 19 extreme Southern species. In contrast, there were no clear trends in the intermediate to Northern and intermediate to Southern species. These results suggest that rising sea surface temperatures have had significant impacts on the occurrence of rarer marine invertebrate species at the edges of their biogeographic range however the trends differed between areas in Northern Ireland. [Copyright &y& Elsevier]

ancellarla corrosa Reeve, 1856, a species described from an unknown locality and believed by early authors to inhabit "China Seas," has been found to be a component of the sublittoral fauna of western Central America. A more detailed description of the shell and radula of this species is provided. As specimens have been misidentified in collections as C. decussata Sowerby I, 1832 or C. gemmulata Sowerby I, 1832, features useful to distinguish these species are provided. Examination of the fossil literature for the region indicates that the lineage giving rise to C. corrosa has been present since at least the middle Miocene. [ABSTRACT FROM AUTHOR]

Data on Amur Bay (the Sea of Japan) are used to show the existence of a dependence between the diurnal variability and the mean daily concentrations of various hydrochemical characteristics, which can be approximated by power function. The formation mechanism of such dependences is considered. Relationships between the parameters of such functions and variability of water salinity are obtained. The possible variation limits of such parameters in a coastal tidal zone of a sea, subject to the effect of coastal runoff. In the frontal mouth zone, one of the parameter (the exponent) linearly increases toward the river, thus reflecting the increase in the contribution of water dynamics to the diurnal variability of characteristics. The notion of variability of characteristics 'by salinity' is introduced. [ABSTRACT FROM AUTHOR]

Abstract: The region of the Bohai Sea is among the most densely populated of any marginal sea worldwide, and the sea is of great commercial importance as one of the major fishing areas in China. In this study, sublittoral macrofaunal community data collected during the 2000s was integrated with historical data from the 1980s to 1990s to detect any change in biodiversity status over the past three decades. Biodiversity was assessed through species diversity, taxonomic relatedness and other measures of community structure. Different geographic locations had different scenarios of decadal biodiversity change. We observed a sustained increase in species diversity in Bohai Bay and a cyclic trajectory in Laizhou Bay. In the central part of the Bohai Sea, there was little change in species diversity, whereas taxonomic distinctness tended to increase. A test for departure from the expected value of taxonomic distinctness (Δ +, Λ +) suggested that approximately one-fifth of the sampling stations were subjected to environmental stress and perturbation. [Copyright &y& Elsevier]

Abstract: Rapid declines in the sea urchin Diadema aff. antillarum densities and shifts in community states of sublittoral rocky reefs have been observed over a short period (between 2004 and 2008) for the first time in an area with fishing restrictions (the MPA of La Palma, Canary Islands, eastern Atlantic Ocean). Changes were spatially variable according to the MPA''s use area considered. During this period there was a sea urchin density reduction (in some cases from 3.34 to 0.45 indv·m−2), and an increase of erect seaweed (up to 30% of cover) in the sites of the no-take area. In the partially restricted fishing area, the effect was less clear and only some sites, near to the no-take area, showed the sea urchin reduction and seaweed growth, in contrast to the increase of sea urchin densities outside the MPA. In addition to increased coverage, there was also a replacement of the ephemeral species by the perennial seaweed Lobophora variegata. These changes were related to increases in the abundance of fish predators of the sea urchins. In the no-take area, where there is total fishing restriction, predators were so abundant to induce shifts in the benthic community, while in the partially protected area such as outside the MPA, fishing prevented the top-down process and the changes in the communities. [Copyright &y& Elsevier]

The heart rate and calpain activity of blue mussels Mytilus edulis from the sublittoral zone, exposed to different levels of water-borne copper and cadmium, was investigated in a long-term experiment. The content of cadmium and copper in the blue mussel was determined using flame and graphite Atomic absorption spectroscopy. The observed concentrations ranged from 2.5 to 89.1 μg/g dry weight for cadmium and from 6.1 to 51.0 μg/g dry weight for copper in the control and highest concentration, respectively. Initially, increase in cardiac activity in response to copper and Cadmium exposure was observed under all pollutant concentrations (5–250 and 10–500 μg/L, respectively). The calpain-like activity in gills and hepatopancreas of the mussels treated with metals changed in dose- and time-dependent manner: from a sharp rise at the 250 μg/L concentration of copper on the first day to a significant decrease under the effect of Cadmium in the concentration of 500 μg/L on the third day of the experiment. These results suggest that: (i) heart rate oscillation may reflect active adaptation of blue mussels to contamination and (ii) animals have different sensitivity to copper and Cadmium according to the role of the metals in the mussels’ life activity. [ABSTRACT FROM PUBLISHER]

Abstract: Historical overfishing is the most likely explanation for the depletion of the shallow sublittoral communities in many areas not least in the Cyclades Archipelago, Greece. The present study is the first quantitative study of the shallow rocky sublittoral of the Cyclades based on in situ underwater surveys of algal cover, and fish and sea urchin abundance at 181 sampling sites in 25 islands to provide a baseline and investigate the relationship between these communities. Algal turf was the most abundant algal functional group, and canopy algae of the genus Cystoseira were more abundant at the northern islands. A range in fish biomass of almost two orders of magnitude was found across islands, but overall the Cyclades displayed much lower values than fished areas of the Western Mediterranean. We observed apex predators only in 25% of our sampling sites, and their biomass was uncorrelated to total fish biomass, indicating a depleted ecosystem. Sea urchin biomass was also low but similar to values found in other Mediterranean islands and was positively correlated with barrens. We observed a gradient of benthic community complexity from sea urchin barrens to communities dominated by Cystoseira spp. There was no correlation between sea urchins and their predators Diplodus spp., which presented extremely low densities. [Copyright &y& Elsevier]

In order to reveal the structure of the sparsely known deeper sublittoral hard bottom communities of glacial Kongsfjorden, the macroepibenthos from six depth zones (30-200 m) was analysed. A total of 180 still images derived from 6-h video recorded at the Kongsfjordneset remotely operated vehicle station were assessed quantitatively. Overall 27 mainly suspension-feeding species/taxa were observed. Of these, two-thirds have an arcto-boreal distribution, while the remainder are cosmopolitan. The overall mean epibenthos abundance was 33 ind. m with maximum values at 150 m depth (97.9 ind. m). The majority of the taxa inhabited the entire depth range. Encrusting red algae, an unidentified sponge and the sea anemone Urticina eques, characterized the assemblage of the shallow zone. The sea anemones Hormathia spp. were important below 30 m, the Serpulid polychaete Protula tubularia was characteristic for the community below 50 m and the demosponge Haliclona sp. was a key taxon between 100 and 200 m depth. Cluster analysis and non-metrical multidimensional scaling based on abundance data showed differences between the assemblages along the bathymetric gradient, but only in the shallower depths in relation to the substratum surface incline. As surface and tidal current impacts attenuate with increasing depth, there is a gradual trend from robust key species towards more fragile ones (i.e. P. tubularia), in line with the 'Physical control hypothesis'. [ABSTRACT FROM AUTHOR]

Abstract: Hermit crabs play an important role in the Northern Adriatic Sea due to their abundance, wide range of symbionts, and function in structuring the benthic community. Small-scale (0.25m2) hypoxia and anoxia were experimentally generated on a sublittoral soft bottom in 24m depth in the Gulf of Trieste. This approach successfully simulates the seasonal low dissolved oxygen (DO) events here and enabled studying the behaviour and mortality of the hermit crab Paguristes eremita. The crabs exhibited a sequence of predictable stress responses and ultimately mortality, which was correlated with five oxygen thresholds. Among the crustaceans, which are a sensitive group to oxygen depletion, P. eremita is relatively tolerant. Initially, at mild hypoxia (2.0 to 1.0mll−1 DO), hermit crabs showed avoidance by moving onto better oxygenated, elevated substrata. This was accompanied by a series of responses including decreased locomotory activity, increased body movements and extension from the shell. During a moribund phase at severe hypoxia (0.5 to 0.01mll−1 DO), crabs were mostly immobile in overturned shells and body movements decreased. Anoxia triggered emergence from the shell, with a brief locomotion spurt of shell-less crabs. The activity pattern of normally day-active crabs was altered during hypoxia and anoxia. Atypical interspecific interactions occurred: the crab Pisidia longimana increasingly aggregated on hermit crab shells, and a hermit crab used the emerged infaunal sea urchin Schizaster canaliferus as an elevated substrate. Response patterns varied somewhat according to shell size or symbiont type (the sponge Suberites domuncula). Mortality occurred after extended anoxia (~1.5d) and increased hydrogen sulphide levels (H2S ~128μmol). The relative tolerance of crabs and certain symbionts (e.g. the sea anemone Calliactis parasitica) – as potential survivors and recolonizers of affected areas – may influence and promote community recovery after oxygen crises. [Copyright &y& Elsevier]

1 - A survey of the macrobenthos community was carried out in Lake Illawarra, NSW, Australia, during April and May 2011. 2 - The aim of this study was to understand the current status of the characteristic macrobenthic fauna community, and the temporal changes over the past 30 years, as well as the impacts of anthropogenic activities on the benthic ecosystem. 3 - Fifteen stations were selected as representative of three main areas of the lake (the entrance channel, the central basin and the sublittoral fringe), which might be impacted by different kinds of human activities. 4 - A total of 45 macrobenthic species were identified. Mollusca represented the most abundant taxon with 17 species, followed by Crustacea with 16 species. Three species were dominant, i.e., the mollusk Nassarius burchardi, and the polychaeta Lumbrineris sp. and Nephtys australiensis. 5 - The abundance and biomass of the macrobenthos were variable between the three main areas. Based on Bray Curtis similarity of macrobenthos, the 15 sites also divided largely into three groups. 6 - M-AMBI index analysis indicated that eight stations (57.1%) had 'good' to 'high' ecological status (EcoQ), four stations (28.6%) 'moderate' EcoQ, and two stations (14.3%) with 'poor' to 'bad' EcoQ, which indicates the Lake Illawarra was in reasonably good condition, but evidence of disturbance and impact on benthic communities was obvious at several sites. [ABSTRACT FROM AUTHOR]

The article presents a study which describes the feeding behavior of dominant sea urchins in Mediterranean sublittoral such as Arbacia lixula and Paracentrotus lividus. The study used stable isotope analysis to test the trophic positions of the species in western Mediterranean and in Macaronesia. Results show that A. lixula occupies a higher trophic level and was suggested to be considered as an omnivore.

Both sexes of a new species of Sentiropsis Huys & Gee, 1996 (Copepoda, Harpacticoida, Pseudotachidiidae) are described from the upper sublittoral zone off Hyeopjae, Jeju Island, Korea. Sentiropsis coreana, new species is very similar to its zoogeographically closest congener, S. vietnamensis Gómez & Chertoprud, 2009 from Nha Trang Bay (Vietnam) in the South China Sea. Females of both species differ primarily in morphometric characters. The presence of a well-developed apophysis on the male P2 endopod of S. coreana serves to distinguish it from the Caribbean type species, S. minuta (Coull, 1973) and calls into question the previously suggested sister-group relationship between Sentiropsis and the Paradanielssenia-lineage characterized by the presence of claviform aesthetascs on the mouthparts. An updated key to the 19 valid genera of the subfamily Danielsseniinae is provided. The genus Carolinicola Huys & Thistle, 1989 is removed from the Pseudotachidiidae and transferred to the subfamily Hemimesochrinae in the Canthocamptidae. [ABSTRACT FROM AUTHOR]

In the Western Mediterranean Sea, the gorgonian Eunicella singularis (Esper, 1794) is found at high densities on sublittoral bottoms at depths from 10 to 70 m. Shallow colonies have symbiotic zooxanthellae that deeper colonies lack. While knowledge of the ecology of the shallow populations has increased during the last decades, there is almost no information on the ecology of the deep sublittoral populations. In October and November 2004 at Cap de Creus (42°19′12″ N; 03°19′34″ E), an analysis of video transects made by a remotely operated vehicle showed that shallow populations (10-25 m depth) were dominated by small, non-reproductive colonies, while deep sublittoral populations (50-67 m depth) were dominated by medium-sized colonies. Average and maximum colony heights were greater in the deeper populations, with these deeper populations also forming larger patch sizes and more extensive regions of continuous substrate coverage. These results suggest that shallow habitats are suitable for E. singularis, as shown by the high recruitment rate, but perturbations may limit or delay the development of these populations into a mature stage. This contrasts with the deep sublittoral habitats where higher environmental stability may allow the development of mature populations dominated by larger, sexually mature colonies. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the mechanisms of ecological succession is fundamental to predict recovery patterns and restore the increasingly disturbed marine habitats; the season in which disturbance occurs severely affects these processes but this factor has not been thoroughly studied in sublittoral cliffs. Thus, seasonal patterns of benthic colonization and succession were investigated on a temperate rocky cliff (Aegean Sea, eastern Mediterranean). Cement panels, seasonally installed on the rocky substratum at 25–30m depth, were sampled every 3months over a 1-year period each, yielding 40 floral and 158 animal species. Diversity, cover and abundance were very low at the initial immersion period and increased toward the late periods. The immersion period and the season of installation had a strong effect on diversity and abundance; decapods showed increased colonization on panels installed in spring, and polychaetes on hibernal panels. The vagile fauna responded to the increasing habitat complexity offered by the development of algal turfs and sessile species. Community structure remained highly dynamic up to the end of the experimental installation and quite different from that of the surrounding benthic community. Two stages of succession, considering vagile and sessile biota, either separately or altogether, were observed over immersion periods; the first was characterized by high variability that can be related to the presence of different colonizers in different seasons, whereas the second, exhibited higher species richness and abundance and showed increased endogenous similarity. Thus, regardless of the season colonization started the developed communities converged toward a common structure, after one year of immersion. An exception was hibernal installation, in which the 12-month immersion period was recognized as a third stage characterized by increased diversity also showing an increased similarity with the adjacent algal community; this suggests that benthic colonization in such environments is faster when succession starts in winter. [Copyright &y& Elsevier]

The article explores two nassariid gastropods' physiological responses to hypoxia. The authors conducted a study using endpoints that includes SfG and other energy budget items in a 31 d experiment. They found that Nassarius siquijorensis experienced reduced energy intake after exposure to stronger hypoxia treatment of 1.5 milligram O2 1¹, while there was a halt in N. conoidalis' feeding. They conclude that significant adverse effect on the environment of the gastropods might result in major environmental changes.