Shallow Sublittoral Zone Research Articles

Pannonian (late Miocene) ostracod fauna from Pécs-Danitzpuszta in Southern Hungary

The large outcrop at Pécs-Danitzpuszta, southern Hungary, exposes a 65-meter-thick succession of calcareous marls, clay marls and calcareous sands that were deposited during the early history of Lake Pannon, a vast, Caspian-type lake in Central Europe in the late Miocene. Within the framework of the complex stratigraphic investigation of this succession, well preserved, relatively diverse benthic ostracod assemblages containing 39 taxa were recovered from 29 samples (16 samples were barren). Palaeoecological interpretation of the ostracod genera suggests that deposition took place in a low-energy environment, in the shallow sublittoral zone of Lake Pannon, in pliohaline (9–16‰ salinity) water. The entire succession was divided into four interval zones based on the first occurrences of assumedly useful marker fossils: Hemicytheria lorentheyi Zone (from sample D29), Hemicytheria tenuistriata Zone (from sample D17), Propontoniella candeo Zone (from sample D115) and Amplocypris abscissa Zone (from sample D209). Based on comparison to the Beočin section 150 km to the SE, where a lithologically and stratigraphically similar section was dated magnetostratigraphically by an international team, we tentatively assume that the Pannonian marl succession of the Pécs-Danitzpuszta outcrop represents the time interval of 11.6 to ca. 10 Ma.

Genetic heterogeneity of two bioeconomically important kelp species along the Norwegian coast

Knowledge of genetic diversity among wild populations is becoming increasingly important as more species are recognized for their bioeconomic value. Industrialization of natural resources, such as kelp in the marine shallow sublittoral zone through cultivation and wild-harvesting, may lead to extensive translocation and local population decimation. Without adequate resilience in the form of genetic diversity within and across populations and given the potential introduction of deleterious alleles from translocations, such anthropogenically pressured populations may not be able to sufficiently respond to future climate and other stressors. Here we provide an assessment of the genetic heterogeneity of two bioeconomically important kelp species, Laminaria hyperborea and Saccharina latissima, across the Norwegian coastal region from South (57°N) to North (78°N), by applying microsatellite genotyping. Isolation by distance was found for both kelp species when comparing genetic distance to geographic distance. L. hyperborea clustered into four distinct genetic groups corresponding to distinct geographical ecoregions, whereas S. latissima did not show equally strong geographical structuring but separated into three geographical clusters along the Norwegian coast. No genetic differentiation was found within the Norwegian Skagerrak region, corroborating previous findings. The identified genetic clustering of both kelp species supports the retention of established management regions along the Norwegian coast and argues for the continuation of a regional focused management plan for kelp resources. Further, the results demonstrate that care should be taken to prevent translocation of kelp between ecoregions in the ongoing industrialization of kelp cultivation, to maintain a healthy coastal ecosystem and sound natural population genetic diversity.

Different Life Histories and Life Styles in Spatangoid Echinoids Living in the Shallow Sublittoral Zone in the Oki-Islands, Japan.

The growth rate, reproduction, recruitment and feeding of four spatangoid species in the Okiislands in the Japan Sea were investigated over five years. Nacospatangus alta, which inhabits unstable surface sediments, grows rapidly, reaches sexual maturity early, and has a short life span, indicating that it should be a ruderal, whereas Metalia spatagus and Brissus agassizii, which inhabit relatively stable deep sediment, grow slowly, reach sexual maturity late, and have a long life span, suggesting that they are stress-tolerators. Lovenia elongata, however, inhabits unstable surface sediment but has an exceptional life history; it grows rapidly, but does not reach sexual maturity early and has a long life span, likely because the specific morphology of its spines and tubercles allow it to cope with surface disturbances caused by storms. Lovenia elongata seems to be a competitive ruderal. A trade-off between test formation and gonad development may occur; N. alta constructs a fragile test with very thin plates, allowing the echinoid to allocate energy to increasing test size and developing the gonad to sexual maturity within a year. Lovenia elongata, with thick plates supporting the specific stout spines and tubercles, needs 2 years to reach sexual maturity with a similar rate of test growth to that of N. alta; M. spatagus and B. agassizii construct robust tests with thick plates, presumably necessary for these species, which burrow and live deep in sand under high pressure from surrounding sand. These echinoids do not reach sexual maturity until over 2 years of age. The flexible trade-off related to stress and disturbance associated with burrowing depth in different habitats allows the spatangoids to have different life-history strategies.

Use of pitfall traps for sampling marine benthic arthropods on soft substrate

AbstractEcological monitoring is a prerequisite for ecosystem-based management and conservation. There is a need for developing an efficient and non-destructive method for monitoring marine benthic arthropods on soft substrate, as the currently applied methods are often inadequate. Pitfall trapping has been used extensively to sample terrestrial arthropods, but has not been seriously considered yet in the marine environment. In this study, the effectiveness of pitfall traps for monitoring marine benthic arthropods was assessed through a case study in the shallow sublittoral zone of Kalloni Gulf, Lesvos Island, Greece. Two different trap types were installed in August 2016 at five depths, during two 12 h periods (day and night). Pitfall traps performed well, collecting a large number of individuals. The hermit crabDiogenes pugilatordominated the catches. The catch of this species significantly differed by trap type, while the interaction between depth and period was also found significant. Further research is needed to evaluate the efficiency of different types of pitfall traps and field protocols in the marine environment.

Tanaidacea fauna (Peracarida, Crustacea) from the shallow sublittoral zone of Admiralty Bay, King George Island, Antarctica, with new records

The Southern Ocean is a very sensitive ecosystem, with the Antarctic Peninsula being one of the most rapidly warming regions on Earth. Accordingly, studies of its biodiversity are of urgent interest. In this context, taxonomical surveys of Antarctic tanaidacean species become relevant, since it is one of the lesser-known Antarctic macrofaunal groups. The present study aims to elucidate the species composition as well as spatial and vertical distribution of tanaidaceans in the shallow sublittoral zone of Admiralty Bay, one of the Antarctic Specially Managed Areas. Sediment samples were taken in the years 2005 and 2010 from 20 and 50 m depth zones at two sites in each of five chosen stations. Three replicate box-corer samples were taken at each site, and the retained sediment was stratified (0–2, 2–6, and 6–10 cm sediment layers). Nine Tanaidacean species (superfamily Paratanaoidea) were identified, with two new species records for Admiralty Bay: Arhaphuroides parabreviremis and Parakanthophoreus antarcticus. In general, Nototanais antarcticus was the dominant species. Significant abundance differences were found among stations, except at 20 m depth in 2005. The Ullmann Point station stood out by the absence of tanaidaceans. No significant differences were found between depths, although 20 m depth sites exhibited higher abundance than 50 m depth ones, which in turn presented higher species richness. Tanaidaceans were concentrated in the first six cm of sediment. Data suggest that the Tanaidacea assemblages in Admiralty Bay have very heterogeneous spatial distribution, reflecting the variety of habitats present in this region.

The reproduction of Anemonia sulcata (Pennant, 1777) (Cnidaria: Anthozoa) in southern Spain

The reproduction of Anemonia sulcata (Pennant, 1777) (Cnidaria: Anthozoa) in southern Spain

Benthic fish guilds in the shallow sublittoral zone of Lough Hyne, Co. Cork, Ireland

The fully marine Lough Hyne in south-west Ireland was designated a marine nature reserve in 1981 because of its high species and habitat diversity as well as intense fishing pressure. Considerable research has described the fish species in the Lough, their behaviour and distributions. Following the population demise of purple urchins in the Lough, the fish communities inhabiting the shallow sublittoral zone, particularly benthic and hyperbenthic fishes, which could be potential predators of sea urchins, were characterised. Three sites were chosen in different parts of Lough Hyne that historically supported dense urchin populations. In August to September 2014, fish density was estimated by snorkel surveying 50m band transects, noting water depth, habitat type and the number of fish by family for each 5m section. The two-way factorial survey design included time of day (morning, midday, late afternoon) and tide (high vs low) as factors with six surveys per transect. Numerically, gobies were the most abundant benthic to hyperbenthic fish in the shallow subtidal habitats; wrasses were the second most abundant. While all factors of site, tide, time and weather had significant effects on fish densities, site was most significant. This pattern indicated that gobies and wrasses were distributed more according to habitat type than small-scale depth and temporal variations, but further work should be done to elucidate nocturnal-diurnal effects and large-scale, seasonal effects. In the absence of direct evidence of predation effects before and after 1981, coupled with observational and/or gut content data, the role of fish predation as the major causal mechanism of urchin demise in the Lough was not supported.

Benthic fish guilds in the shallow sublittoral zone of Lough Hyne, Co. Cork, Ireland

Benthic fish guilds in the shallow sublittoral zone of Lough Hyne, Co. Cork, Ireland

DEPOSITIONAL ENVIRONMENTS, DIAGENETIC PROCESSES AND THEIR IMPACT ON RESERVOIR PROPERTIES OF UPPER SILURIAN-LOWER DEVONIAN CARBONATES IN R. TREBS AND A. TITOV FIELDS

The article considers the conditions of formation of upper Silurian-lower Devonian carbonate deposits of a name of Roman Trebs and Anatoly Titov fields in Timan-Pechora postbaikal plate. Shown facies heterogeneity of the sediments and their association with epicontinental carbonate platform. Identified multi-scale sedimentary cyclicity regressive type, due to tectono-eustatic sea level fluctuations. Allocated 6 major of cyclites corresponding to the number of productive carbonate layers. It is established that the sedimentation occurred in three bathymetric zones in the basin: the subtidal, intertidal and supratidal with characteristic sets of structural-genetic types of rocks. In relatively deep-water sublittoral selected primarily clay lithotypes; in the shallower parts - transitional lithotypes, with approximately equal proportions of clay and granular components; in the hydrodynamically mobile area of shallow sublittoral zone - the most granular rocks. It was found that the basic processes postsedimentary transformation of carbonate rocks were dolomitization, fracturing, leaching and cementation. It is shown that cementation has led to the declining of reservoir properties, cracking is a marginal effect on the filtration properties of rocks and dolomitization and, especially, leaching manifested the most ambitious and determined the development of secondary void space and formation of high quality collectors. According to porosity/permeability value with regard to the size of the dolomite crystals all of lithotypes divided into three petrophysical classes, that well comparable to the environments of sedimentation and secondary alterations of the reservoirs. It is shown that predominantly granular greinstones with grain size of 100-500 microns have the best reservoir properties. To select petrophysical classes in the productive carbonate section as an effective log method proposed the focused electrode logs.

Experimental test of host specificity in a behaviour-modifying trematode.

Host behavioural modification by parasites is a common and well-documented phenomenon. However, knowledge on the complexity and specificity of the underlying mechanisms is limited, and host specificity among manipulating parasites has rarely been experimentally verified. We tested the hypothesis that the ability to infect and manipulate host behaviour is restricted to phylogenetically closely related hosts. Our model system consisted of the brain-encysting trematode Euhaplorchis sp. A and six potential fish intermediate hosts from the Order Cyprinodontiformes. Five co-occurring cyprinids were examined for naturally acquired brain infections. Then we selected three species representing three levels of taxonomic relatedness to a known host to experimentally evaluate their susceptibility to infection, and the effect of infection status on behaviours presumably linked to increased trophic transmission. We found natural brain infections of Euhaplorchis sp. A metacercariae in three cyprinids in the shallow sublittoral zone. Of the three experimentally exposed species, Fundulus grandis and Poecilia latipinna acquired infections and displayed an elevated number of conspicuous behaviours in comparison with uninfected controls. Euhaplorchis sp. A was able to infect and manipulate fish belonging to two different families, suggesting that ecological similarity rather than genetic relatedness determines host range in this species.

INFLUENCE OF SEDIMENT QUALITY ON THE BENTHIC COMMUNITIES OF ADMIRALTY BAY, KING GEORGE ISLAND, ANTARCTICA

Marine benthos is widely used in environmental impact studies, especially in coastal areas. In the summer of 2010, three areas of Martel Inlet and one in Mackellar Inlet were sampled in order to verify the marine environmental status near the Brazilian Station Comandante Ferraz (CF). In the shallow sublittoral zone (20 m depth), sediment samples were collected to analyze their physical characteristics, quality and indicators of anthropic activities (grain size, organic matter, phytopigments, linear alkylbenzenes, faecal sterols, microbiological indicators, hydrocarbons, persistent organic pollutants and metals) and to evaluate the meio- and macrofauna communities structure. Meiofauna densities were in the range of those found in previous studies in the bay and did not differ significantly among sampling sites. Nematodes were the dominant group. On the other hand, macrofauna densities were significantly higher in Mackellar Inlet, when comparing with some sites of Martel Inlet. Polychaetes, oligochaetes and bivalves were the dominant macrofauna taxa. Correlation analysis showed that different sediment characteristics could explain the abundance of the meiofauna or the macrofauna groups in a different way. Change in the meio- and macrobenthic community structure was detected at the site under the CF sewage outfall influence (lower density of meiofauna, different taxa composition of macro- and meiofauna), where relatively higher concentrations of linear alkylbenzenes and coprostanol, and densities of Escherichia coli and Clostridium perfringens were found. These results suggest some local impact of human activities on the benthic system in front of the Brazilian Research Station and contribute to the monitoring program under the scope of the INCT-APA (National Institute of Science and Technology - Antarctic Environmental Research).

Rhoicosphenia michali: a new species of marine diatom (Bacillariophyta) from King George Island, Antarctica

Rhoicosphenia michali sp. nov., described from the shallow sublittoral zone in Antarctica, is the second species in the genus with just one raphe slit on its convex valve. The first species, Rhoicosphenia flexa, was also described from marine coastal habitats in the Southern Hemisphere. Here, the morphology and ecology of R. flexa and R. michali are compared. The new species described herein may be endemic to Antarctica and can be found as free living cells on the shallow seabed, although it mainly occurs on the red alga Georgiella confluens, which is endemic to Antarctica.

The first report on Amphipoda from Marian Cove, King George Island, Antarctic

Abstract 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.

A new occurrence of classic “Árpád-type” mollusk fauna from the Upper Miocene of Kozármisleny, southern Hungary

A classic but very rare “Arpad-type” mollusk assemblage, representing the endemic fauna of the Late Miocene–Early Pliocene Lake Pannon, was discovered in Kozarmisleny (near Pecs, southern Hungary). The fossils were collected from silt layers deposited in the shallow sublittoral zone of Lake Pannon, and exposed by an 8–10 m high road cut. The assemblage contained some very rare species, including the type species of genus Lymnocardium, L. haueri (M. Hornes). Palynological investigations from the same layers failed to yield age-diagnostic dinoflagellates, and pointed to strongly freshened water and warm, subtropical climate.

The seaweeds of Angola: the transition between tropical and temperate marine floras on the west coast of southern Africa

The seaweed flora of Angola is relatively poorly known. Most of the 124 records listed for the country come from a 1974 British Natural History Museum expedition to the central and southern parts of that country. Previous biogeographic studies treated the Angolan seaweed flora as a whole and grouped it with those of certain West African islands as transitional between a Tropical West African seaweed flora (essentially extending from Senegal to Gabon) and temperate floras to the north and south of this truly tropical region. In the present study a total of 99 species and subspecies of seaweeds was collected from the intertidal zone and shallow sublittoral zones at five sites in the north of Angola and four sites in the south. The biogeographic distributions of our records were examined and compared with the temperate flora of Namibia to the south and the flora of Ghana to the north (as an example of a well-studied Tropical West African flora). Multivariate analyses of our presence/absence records showed differences between northern and southern sites (cluster analysis [Jaccard, average linkage] and detrended correspondence analysis). All Angolan sites were clearly different from floras of south, central and northern Namibia, which are considered to be strictly temperate in nature. Northern Angolan sites grouped more closely with Ghana than with southern Angolan sites. Distribution patterns within Angola are discussed in relation to monthly sea surface temperature data that were processed for this region. We conclude that the overall affinities of the Angolan seaweed flora, as represented by our collections, are Tropical West African, but with a well-developed temperate element in southern Angola (from about 13° S) comprising mainly cooler-water species from the Benguela Marine Province of Namibia and western South Africa. Our collections add about 45 species to the Angolan seaweed flora, raising the total number of species to around 169. This total approaches that of Ghana which, with about 200 species, is considered to have the richest seaweed flora in Tropical West Africa.

Population dynamics and reproduction of Holothuria tubulosa (Holothuroidea: Echinodermata) in the Aegean Sea

The Atlanto-Mediterranean holothurian Holothuria tubulosa is among the conspicuous benthic invertebrates in the shallow sublittoral zone. It is an edible species, harvested at the Aegean Sea and utilized as fishing bait. Considering the lack of information for the Aegean populations, a one-year survey, based on monthly or semimonthly samples, was carried out focusing on population structure, allometric relationships and reproductive status of H. tubulosa stocks in Pagasitikos Gulf. Population density varied around 9.93 individuals/100 m2. This value was rather low compared with other studied Mediterranean populations of the species, possibly due to the scarcity of seagrass meadows in the area studied. All measured biometric characters showed high plasticity, and all the examined morphometric relationships followed negative allometry indicating a change to the shape of the animal's body as it grows. Holothurians’ length was a moderate predictor of biomass since r values reached 60%; in contrast a very strong relation was observed between drained and gutted weight. Size–frequency distribution analysis was unimodal with the exception of spring where a second mode of larger sized individuals appeared. The gonadosomatic index showed a single spawning season per year, in late summer; accordingly the reproductive cycle of the species showed a clear annual pattern which was highly correlated with the seasonal variations of temperature.

Marine epiphytic diatoms from the shallow sublittoral zone in Potter Cove, King George Island, Antarctica

Abstract Marine epiphytic diatoms in the Antarctic Peninsula have not been studied in detail previously, and information on their distribution and occurrence is scarce. We studied the marine epiphytic diatoms on several species of macroalgae belonging to the Rhodophyta, Phaeophyceae and Chlorophyta. We recorded a total of 50 epiphytic diatoms, with Cocconeis spp., Entopyla australis var. gigantea, Grammatophora arctica, Licmophora antarctica and Pseudogomphonema kamtschaticum the most common taxa. Diatoms appeared to have substratum preferences rather than site preferences. The most frequent hosts for diatom attachment were the rhodophytes Pantoneura plocamioides, Delesseria lancifolia and Georgiella confluens. Phaeophytes were less favourable hosts, and no diatoms were recorded on the chlorophytes.

The limpet Patella vulgata L. at night in air: effective feeding on Ascophyllum nodosum monocultures and stranded seaweeds

Opportunistically, the limpet Patella vulgata will switch from microphagous grazing to feeding on attached macroalgae or, a novel finding, on accumulations of stranded seaweeds. Macroalgal food is ingested primarily at night during emersion, when the thalli come to lie on the rock surface and are sufficiently damp. Monocultures of Ascophyllum nodosum are not immune to the destructive effects of limpets as previously thought. Patella vulgata can graze them down to complete disappearance, thus pushing Ascophyllum back to refuges where P. vulgata is absent or rare. Such refuges were found along a wide range from very sheltered to strongly wave-exposed rocky shores in Brittany, France. By a combination of its macrophagous and microphagous feeding habits, P. vulgata can control mid-tidal macroalgal assemblages in a similar fashion to the action of sea urchins upon kelp communities inhabiting the lower intertidal and shallow sublittoral zones of rocky shores.

New records of benthic marine algae from the Canary Islands (eastern Atlantic Ocean): morphology, taxonomy and distribution

Abstract Four species of marine algae are reported from the Canary Islands for the first time. Our report of the western Atlantic Gelidiella setacea (Gelidiales, Rhodophyta) is the first from the eastern Atlantic Ocean. Pseudotetraspora marina (Tetrasporales, Chlorophyta) previously known on the eastern side of the Atlantic Ocean from temperate saltmarshes only, is now reported growing in the shallow sublittoral zone, the habitat in which tropical western Atlantic populations also occur. The presence of Lomentaria chylocladiella (Rhodymeniales, Rhodophyta) represents the first report in the Atlantic Ocean of a species previously thought to be endemic to the Mediterranean Sea. The record of the widely distributed Acrochaetium hallandicum (Acrochaetiales, Rhodophyta) was not unexpected. Specimens of A. hallandicum have vegetative cells with a single lobate parietal chloroplast with a single pyrenoid, a feature that among acrochaetioid algae occurs exclusively in the genus Colaconema (Colaconematales), and consequently the species is transferred to this genus. Fertile sporophytes are described for Gelidiella setacea, a species previously known only in its vegetative condition. Cruciately to irregularly divided sporangia are regularly arranged in transverse rows in stichidia laterally formed on the axes. The species is transferred to the genus Parviphycus on the basis of the morphology of the stichidia and the distichous pattern of apical division exhibited by the axes, both exclusive features of this genus.

Vertical distribution of macrobenthic infauna from the shallow sublittoral zone of Admiralty Bay, King George Island, Antarctica

A 0.0625 m2 mini-box corer (MBC) was used to study the vertical distribution of macrobenthos in the shallow sublittoral zone of Admiralty Bay, during the 2003/2004 summer, near the Brazilian Station Comandante Ferraz, and the Peruvian Station Machu Picchu. Sediment samples were taken from 20, 30 and 60 m, and stratified for particle-size, total organic matter (TOM) and faunal composition analysis. The most abundant taxa were Polychaeta, Oligochaeta, Amphipoda, Cumacea, Bivalvia and Gastropoda. In general, macrofauna were concentrated in the 0–4 cm layer (64% of total organisms). Correlations between sediment characteristics and faunal densities have not completely explained neither the aggregation of organisms at the surface sediment layers nor the differences in faunal composition between locations at 20 m depth. Analysis of parameters such as organic carbon, heavy metals, interstitial water, and species composition should contribute to a better understanding of the diversity patterns found in this study.