Taxonomic composition and distribution of soft-walled monothalamid foraminifera in the area of Zernov’s Phyllophora Field (NW Black Sea)

We studied assemblages of soft-walled, single-chambered foraminifera (monothalamids) at eight stations in the area of Zernov's Phyllophora Field (ZPF) on the NW continental shelf of the Black Sea. This work is based on samples collected during Cruise 70 of the RV Professor Vodyanitsky and provides the first analysis of the taxonomic composition of monothalamids from this region. These delicate, poorly known foraminifera were found at all stations in the studied area. They were represented by nine forms that are identified to species or genus level as well as 14 undescribed species, nine of which are found in the Black Sea for the first time. Four species, Psammophaga sp., Vellaria pellucida, Goodayia rostellata and Krymia fusiformis, were most abundant, with Psammophaga sp. being the dominant species overall. Previous studies have suggested a link between members of this genus and eutrophication. There are a number of taxonomic parallels between these ZPF assemblages and those from the Adriatic Sea, e.g. the occurrence of the genera Goodayia, Psammophaga and Vellaria, although it is possible that some other taxa are endemic to the Black Sea.     

Pleistocene agglutinated foraminifera from the Lomonosov Ridge and Amundsen Basin, Arctic Basin. Initial report on piston cores 2177-5 (KAL) and 2176-3 (KAL)

Noncalcareous Pleistocene sediments of the Central Arctic Ocean contain sparse benthic foraminiferal assemblages consisting entirely of agglutinated taxa. Deep water agglutinated foraminifera are studied from two piston cores collected from the Lomonosov Ridge and Amundsen Basin [Cores PS 2177-5 (KAL) and 2176-3 (KAL)]. Core PS 2177-5 (KAL) contains an assemblage of 10 species, dominated by Cyclammina pusilla Brady, and is interpreted to reflect a bathyal environment with variable organic flux and nutrition levels. Core PS 2176-3 (KAL) in the Amundsen Basin yielded a very depauperate benthic foraminiferal assemblage. It is assumed that the environment was inhospitable for agglutinated foraminifera.     

Larger agglutinated foraminifera of McMurdo Sound, Antarctica: Are Astrammina rara and Notodendrodes antarctikos allogromiids incognito?

Explorers Cove, an embayment on the oligotrophic western side of McMurdo Sound, Antarctica, is noted for physical and biological similarities to the deep sea. This locality is an important site for foraminiferal biologists because large, deep-sea-like agglutinated taxa are abundant at depths accessible to divers. Using microdissection methods, we found that many of the giant, single-chambered species from this locality display an allogromiid internal organization (i.e., a monothalamous cell body encased by an organic wall or “theca”). Another characteristic feature of these species is the presence of a distinct space separating the cell body and agglutinated test. We used high voltage transmission electron microscopy of thick sections to examine the theca of Astrammina rara, a dominant Explorers Cove species possessing a simple spherical test morphology, and Notodendrodes antarctikos, a distinctive arborescent species. We found that the simple gross morphology of A. rara's agglutinated test belies the complex ultrastructure of its allogromiid-like theca, and that the complex dendritic morphology of N. antarctikos' agglutinated test contradicts the simple ultrastructure of its theca. Additional field and laboratory observations on A. rara revealed that the agglutinated test can be a transient structure. Our observations raise questions regarding the taxonomy and phylogeny of unilocular agglutinated foraminifera and other primitive granuloreticuloseans. The results are also discussed in terms of test function in larger agglutinated foraminifera and the ecology of this important taxon.     

Lower Cretaceous benthic foraminifera from DSDP Site 263: micropalaeontological constraints for the early evolution of the Indian Ocean

Analysis of 66 samples from DSDP Site 263 (Cores 263-4R-4 to 263-29R-4) reveals a unique faunal composition with a predominance of agglutinated taxa, many of them previously unrecorded from any other DSDP and ODP Indian Ocean sites. A total of 66 agglutinated and 31 calcareous taxa are documented and five new species are described: Hippocrepina gracilis n.sp., “Textulariopsis” elegans n.sp., Aaptotoichus challengeri n.sp., “Gaudryinopsis” pseudobettenstaedti n.sp. and “Gaudryina” cuvierensis n.sp. Three assemblages are recognized based on changes in the composition of dominant taxa and occurrences of stratigraphically important species: (1) a high-diversity Valanginian to Barremian Bulbobaculites-Recurvoides Assemblage (Cores 263-29R to -18R), comprised of numerous elongate agglutinated forms, rare nodosariids, and variable numbers of tubes and ammodiscids; (2) a moderately diverse Aptian to Albian Rhizammina-Ammodiscus-Glomospira Assemblage (Cores 26318R to -7R) with highly fluctuating numbers of the nominate taxa and Haplophragmoides, Trochammina, Verneuilinoides spp., and Vemeuilina howchini; (3) a very low diversity Albian or younger Assemblage (Cores 263-6R to -4R) containing sparse agglutinated foraminifera, rare nodosariids and rotaliids. We interpret the assemblages as shelf to lower slope and consider them to reflect a deepening palaeobathymetry as the Cuvier margin subsided after the initial breakup of East Gondwana during the Valanginian. Our interpretation is in sharp contrast with initial palaeodepth estimates of less than 100 m, as well as with original chronostratigraphic interpretations based on foraminifera and nannofossils which correlated the base of the recovered interval with the Aptian. The absence of many cosmoplitan forms, despite high diversity, suggests strong faunal differentiation in the Austral realm or endemisn within the Cuvier Basin during the Early Cretaceous.     

Demographic structure and distribution of John Dory, Zeus faber L. 1758, in the Adriatic Sea

Recent demographic structure and distribution of the fish species Zeus faber in the Adriatic Sea were investigated in this study and compared with a 1948–1949 study. The presence of John Dory in the Adriatic Sea was recorded at a depth range from 21 to 239 m, with the highest biomass indices at depths between 50 and 100 m. The length frequency distribution, length–weight relationships, sex ratio and length at first sexual maturity were determined. Results based on data from the 1948–1949 ‘Hvar’ expedition and the MEDITS surveys of 1996–1998 showed in the 50‐year interval that the index of biomass and area of distribution of this species in the Adriatic Sea have been reduced and that the demographic structure of the population has changed. Negative changes described in the paper indicate an overfishing of the Z. faber species in the Adriatic Sea.     

Genetic evidence for the identity of Caulerpa racemosa (Forsskål) J. Agardh (Caulerpales,Chlorophyta) in the Adriatic Sea

Three taxa of Caulerpa racemosa that differ morphologically and genetically have been reported in the Mediterranean Sea. The ‘invasive variety’ was recorded for the first time in the early 1990s in Libya. In less than 10 years, it was found in almost all parts of the Mediterranean. The first record of C. racemosa in the Croatian part of the Adriatic Sea was in 2000 and as many as 35 different localities were established by the end of 2004. In terms of morphology, the specimens from the Adriatic Sea resemble the ‘invasive variety’. To confirm this, we analysed populations from two different localities (the island of Mljet and the peninsula of Pelje?ac) using the ITS1-5.8S-ITS2 region of 18S-5.8S-26S rDNA unit as a molecular marker. The ITS1-5.8S-ITS2 region from nine individual plants was amplified by PCR, cloned in a pCR 2.1 vector and sequenced. Phylogenetic comparison of sequences from specimens found in the Adriatic Sea with specimens of the same and similar taxa, found both inside and outside the Mediterranean, provided genetic evidence that C. racemosa populating the Adriatic Sea corresponds to the Mediterranean C. racemosa var. cylindracea (Sonder) Verlaque, Huisman?&?Boudouresque, i.e. to the ‘invasive variety’.     

Molecular Phylogeny and Morphology of Leannia veloxifera n. gen. et sp. Unveils a New Lineage of Monothalamous Foraminifera

Monothalamous (single‐chambered) foraminifera have long been considered as the “poor cousins” of multichambered species, which calcareous and agglutinated tests dominate in the fossil record. This view is currently changing with environmental DNA surveys showing that the monothalamids may be as diverse as hard‐shelled foraminifera. Yet, the majority of numerous molecular lineages revealed by eDNA studies remain anonymous. Here, we describe a new monothalamous species and genus isolated from the sample of sea grass collected in Gulf of Eilat (Red Sea). This new species, named Leannia veloxifera, is characterized by a tiny ovoid theca (about 50–100 μm) composed of thin organic wall, with two opposite apertures. The examined individuals are multinucleated and show very active reticulopodial movement. Phylogenetic analyses of SSU rDNA, actin, and beta‐tubulin (ß‐tubulin) show that the species represents a novel lineage branching separately from other monothalamous foraminifera. Interestingly, the SSU rDNA sequence of the new species is very similar to an environmental foraminiferal sequence from Bahamas, suggesting that the novel lineage may represent a group of shallow‐water tropical allogromiids, poorly studied until now.     

Seaweed fails to prevent ocean acidification impact on foraminifera along a shallow‐water CO2 gradient

Ocean acidification causes biodiversity loss, alters ecosystems, and may impact food security, as shells of small organisms dissolve easily in corrosive waters. There is a suggestion that photosynthetic organisms could mitigate ocean acidification on a local scale, through seagrass protection or seaweed cultivation, as net ecosystem organic production raises the saturation state of calcium carbonate making seawater less corrosive. Here, we used a natural gradient in calcium carbonate saturation, caused by shallow‐water CO₂ seeps in the Mediterranean Sea, to assess whether seaweed that is resistant to acidification (Padina pavonica) could prevent adverse effects of acidification on epiphytic foraminifera. We found a reduction in the number of species of foraminifera as calcium carbonate saturation state fell and that the assemblage shifted from one dominated by calcareous species at reference sites (pH ~8.19) to one dominated by agglutinated foraminifera at elevated levels of CO₂ (pH ~7.71). It is expected that ocean acidification will result in changes in foraminiferal assemblage composition and agglutinated forms may become more prevalent. Although Padina did not prevent adverse effects of ocean acidification, high biomass stands of seagrass or seaweed farms might be more successful in protecting epiphytic foraminifera.     

Distribution of living benthic Foraminifera on the back-reef and outer slopes of a high island (Moorea French Polynesia)

Living foraminifera were examined on both sides of the barrier reef across a section situated on the north-west part of the high island of Moorea (Society Archipelago, French Polynesia). In all, 87 species were found: 62 in the back-reef area (fringing reef, channel and barrier reef) and 72 on the outer slope; 47 were common to both zones. This study points out the importance of substrates in the distribution pattern of foraminifera. The sediments are essentially inhabited by epipsammitic species, whereas algae are colonized mainly by free-living foraminifera: miliolids in the back-reef area; rotaliids in the outer slope. Free-living individuals are much less abundant in the fringing reef, channel and inner part of the barrier reef than in the other parts of the study area. The two major groups on the two sides of the barrier reef are very different in size, test building and probably nutritional modes. In the back-reef area, epipsammitic taxa, mainly composed of small agglutinated species, dominate the fauna; in the outer slope large calcareous symbiotic Amphistegina are the major components of the living association (50 to 70%).     

Benthic foraminiferal fauna during the time of the Indian-Asian contact, in southern Balochistan, Pakistan

Cretaceous and early Paleocene benthic foraminifera were studied from one section along the western Gaj River, southern Balochistan, Pakistan, to reconstruct the paleoenvironment of the Tethys Sea during the Indian-Asian contact. We recognize three lithostratigraphic units in ascending order: the Mughal Kot Formation, the Pab Sandstone, and the Jamburo Group. Both the Maastrichtian Mughal Kot Formation, which consists of shale with grey marly limestone, and the Maastrichtian Pab Sandstone, which consists of quartzose sandstone, indicate an open ocean environment as they have diversified planktic and benthic foraminiferal assemblages. The Maastrichtian-Paleocene Jamburo Group, consisting of dark grey, calcareous shale and marlstone with some sulfide grains, is characterized by low diversities of benthic assemblages. The change to the lower diversities may be associated with the development of poor circulation of deeper water that was caused by narrowing of the Tethys Sea.The Trochammina spp. Assemblage from the Jamburo Group, which can be correlated with flysch-type agglutinated foraminiferal assemblages, has a low benthic species diversity, indicating an unfavorable condition for calcareous foraminifera because of the development of oxygen-depleted water. The absolute abundance of agglutinated specimens shows a remarkable change from low numbers in the Maastrichtian to high ones in the Paleocene. The benthic foraminiferal evidence supports the hypothesis that the collision of the Asian and Indian plates occurred near the end of the Cretaceous.     

Deep-sea benthic foraminiferal recolonization of the 1991 Mt. Pinatubo ash layer in the South China Sea

A census count of Rose Bengal stained benthic foraminifera from the surface area on top of a 2 to 6 cm thick ashfall layer at three deep water stations along the western margin of the Philippines exhibits a unique assemblage composition of benthic foraminifera. The total number of benthic foraminifera is low and the ratio of living individuals to empty tests is high. Specific diversity is low, with a significant dominance of infaunal morphotypes including species of the genus Reophax (R. scorpiurus, R. bilocularis and R. dentaliniformis), which are regarded as successful recolonizers. Assemblages below the ash layers are diverse and contain many epifaunal suspension-feeding agglutinated and calcareous foraminifera. The 1991 Mt. Pinatubo eruption caused mass mortality of benthic foraminifera in a vast area of the eastern South China Sea followed by step-wise recolonization of the ash substrate. Three years after the eruption, the benthic foraminiferal community structure is still far from recovery to background levels.     

A new genus of xenophyophores (Foraminifera) from Japan Trench: morphological description,molecular phylogeny and elemental analysis

The deep‐sea floor is inhabited by a number of unusual and enigmatic taxa, unknown in shallow waters. These include the xenophyophores, a group of giant protists that construct fragile agglutinated tests. Here, we describe Shinkaiya lindsayi gen. et sp. nov. , a new xenophyophore collected by the submersible Shinkai 6500 at a depth of 5435 m near the Japan Trench. The phylogenetic analysis performed on its complete small‐subunit ribosomal DNA (SSU rDNA) sequence confirms that Sh. lindsayi sp. nov. is a foraminiferan that is closely related to another xenophyophore, Syringammina corbicula Richardson, 2001, and to a monothalamous (single‐chambered) foraminiferan Rhizammina algaeformis Brady, 1879. In terms of morphology, the new genus resembles Syringammina, but its test wall is thicker, softer, and more weakly cemented. Moreover, the SSU rDNA sequences of the two genera are highly divergent. Mass spectra analyses reveal unusually high concentrations of some elements, such as lead, uranium, and mercury. The granellare system (the cytoplasm and the organic sheath that encloses it) is apparently devoid of barite crystals, which are usually abundant as intracellular inclusions in xenophyophores, but is rich in mercury (with 12 times the concentration of mercury found in the surrounding sediment). Fecal pellets retained within a tubular system (stercomare) concentrate heavy metals, including lead and uranium (respectively, two and six times more than that of the sediment). Based on a comparison of the compositions of the agglutinated test wall, the granellare, the stercomare, and the surrounding sediment, we discuss the impact of xenophyophores on their habitat. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 455–464.     

Range‐wide population structure of European sea bass Dicentrarchus labrax

The euryhaline European sea bass Dicentrarchus labrax L., inhabiting the coasts of the eastern Atlantic Ocean and Mediterranean Sea, has had many opportunities for differentiation throughout its large natural range. However, evidence for this has been incompletely documented geographically and with an insufficient number of markers. Therefore, its full range was sampled at 22 sites and individuals were genotyped with a suite of mapped markers, including 14 microsatellite loci (N = 536) and 46 neutral or gene‐linked single nucleotide polymorphisms (SNPs; N = 644). We confirm that the Atlantic and Mediterranean basins harbour two distinct lineages. Within the Atlantic Ocean no pattern was obvious based on the microsatellite and SNP genotypes, except for a subtle difference between South‐eastern and North‐eastern Atlantic sea bass attributed to limited introgression of alleles of Mediterranean origin. SNP genotypes of the Mediterranean lineage differentiated into three groups, probably under the influence of geographical isolation. The Western Mediterranean group showed genetic homogeneity without evidence for outlier loci. The Adriatic group appeared as a distinct unit. The Eastern Mediterranean group showed a longitudinal gradient of genotypes and most interestingly an outlier locus linked to the somatolactin gene. Overall, the spatial pattern fits those observed with other taxa of between‐basin segregation and within‐basin connectivity, which concurs well with the swimming capabilities of European sea bass. Evidence from a few outlier loci in this and other studies encourages further exploration of its regional connectivity and adaptive evolution.     

Orthoglymma wangapeka gen.n., sp.n. (Coleoptera: Carabidae: Broscini): a newly discovered relict from the Buller Terrane,north‐western South Island,New Zealand,corroborates a general pattern of Gondwanan endemism

Orthoglymma Liebherr, Marris, Emberson, Syrett & Roig‐Juñent gen.n. (Coleoptera: Carabidae: Broscini) is described to accommodate the single type species Orthoglymma wangapeka Liebherr, Marris, Emberson, Syrett & Roig‐Juñent sp.n., known from the Wangapeka Track, Kahurangi National Park, north‐western South Island, New Zealand. Orthoglymma wangapeka sp.n. is analysed cladistically along with a comprehensive array of 42 other broscine generic terminals and four out‐group taxa, using information obtained from 73 morphological characters, and placed as adelphotaxon to the remainder of subtribe Nothobroscina, a clade distributed in New Zealand, southern South America and Australia. Based on fossil evidence for Carabidae, the occurrence of Orthoglymma wangapeka sp.n. on the Buller Terrane, a geological feature once situated on the eastern margin of Gondwana, and early cladistic divergence of Orthoglymma from the remaining Nothobroscina, Orthoglymma wangapeka sp.n. is interpreted as a Gondwanan relict. The New Zealand arthropod fauna is reviewed to identify other taxa in existence at the time of Cretaceous vicariance of New Zealand and Australia. These candidate Gondwanan taxa, all of which are specified using fossil data or molecular divergence‐based estimates, are analysed biogeographically. Where phylogenetic hypotheses are available, primordial distributions are optimized using event‐based, dispersal‐vicariance (DIVA) analysis. The hypothesized Gondwanan‐aged taxa demonstrate inordinate fidelity to the Gondwanan‐aged geological terranes that constitute the western portions of New Zealand, especially in the South Island. Persistence of these relicts through a hypothesized ‘Oligocene drowning’ event is the most parsimonious explanation for the concentration of Gondwanan relicts in the Nelson, Buller and Fiordland districts of the South Island. Geographic patterns of Gondwanan‐aged taxa are compared with distributions of taxa hypothesized to have colonized New Zealand across the Tasman Sea from Australia and New Caledonia, subsequent to Cretaceous vicariance. These post‐Gondwanan taxa exhibit very different patterns of distribution and diversification in New Zealand, including: (i) abundant endemism in Northland, and the islands and peninsulas of the North Island; (ii) species geographically restricted to areas underlain by the youngest Rakaia and Pahau geological terranes; and (iii) species exhibiting exceedingly widespread geographic distributions spanning geological terranes of disparate ages.

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Benthic foraminiferal distributions in Chilean fjords: 47°S to 54°S

Surface sediment samples collected from the fjord region of southern Chile (47° to 54° South) were analyzed for benthic foraminifera. A total of 175 species were identified including agglutinated and calcareous benthic taxa. Hierarchical cluster analysis of the foraminiferal data resulted in the recognition of three distinct biofacies: inner-fjord, intermediate fjord and channel, and oceanic biofacies, geographically controlled by relative position between the Pacific Ocean and fjord heads. Similarity percentage (SIMPER) analysis identified key taxa in the definition of the biofacies that include Globocassidulina rossensis, Cassidulina laevigata and Bulimina notovata. Principal components analysis resulted in two principal components representing sediment size, and bottom water temperature and salinity.Regional distributions are strongly controlled by the oceanographic conditions influenced from the Pacific in the west and the glacial/freshwater input from the east. Localized distributions of foraminifera are controlled by conditions influenced by the physiography of the individual fjords and channels. The distribution of Chilean fjord foraminifera and their environmental associations are consistent with results from other temperate to high latitude fjord foraminiferal studies.     

Organochlorine pesticides in Muraena helena L. 1758 from the Eastern Adriatic Sea

This work examines the bioaccumulated organochlorine compounds in Muraena helena to draw attention to this species as a potential bioindicator organism. The morays were caught in the East Adriatic Sea, Elaphite Islands, near Dubrovnik, Croatia (lat: 42°45′38.8″; long: 17°45′53.6″) at the same location in summer (August, 2009) and winter (January, 2010), at depths from 5 to 10 m. Nine fish were caught by longline hooks per each field trip (total in summer and winter, N = 18). No single fish was free of organochlorines (OC), but not all pesticides were present in every fish. The concentration level was: Endrin > ppDDE > Heptachlor epoxide > Heptachlor > Aldrine > Lindane > βHCH > δHCH > Endrin aldehyde). Endrin was the only pesticide approaching the maximum concentrations proposed by the European Union and Croatia (summer max. concentration = 14.75 μg kg^?1; winter max. concentration = 8.35 μg kg^?1). All other pesticides ranged from 0.1 to 0.7 μg kg^?1. Heptachlor was absent in winter and δ‐HCH and Endrin aldehyde in summer, while Lindane and pp‐DDE had higher (P ≤ 0.05) concentrations in summer. Other residues had similar seasonal concentration levels. The p‐DDT was similar as in other biota from the Adriatic or Mediterranean. HCH concentrations corresponded to those found in organisms from the Italian area of the Adriatic. The endocrine and reproductive disrupting potential of the detected OCs are bases for future studies. Results show that morays are a good bioindicator model, with slight interspecies and seasonal variability in OC bioaccumulation as a consequence of diverse food consumption.     

Experimental dissolution of a fossil foraminiferal assemblage (Paleocene–Eocene Thermal Maximum,Dababiya, Egypt): Implications for paleoenvironmental reconstructions

Dissolution experiments were carried out on a foraminiferal assemblage from the Paleocene–Eocene Thermal Maximum (PETM) at Dababiya, Egypt, in order to: 1) reveal the effects of differential dissolution on the composition of the foraminiferal assemblage and 2) develop objective criteria for the evaluation of dissolution in foraminiferal assemblages used in early Paleogene paleoenvironmental reconstructions, particularly with respect to neritic Midway-type assemblages from the Paleocene/Eocene transition. Our results confirm two general observations on modern foraminifera: 1) planktic foraminifera are much more vulnerable to dissolution than benthic foraminifera, leading to depressed P/B ratios and 2) dissolution susceptibility differs between size fractions, with the smaller specimens dissolving more rapidly than the bigger ones, leading to a larger average size of the remaining assemblage. Within a size fraction, wall structure and thickness are considered to be the main factors controlling differential dissolution susceptibility. We propose a ranking scheme for taxa with respect to dissolution resistance. Among the benthic taxa, Lenticulina is most resistant, followed by the agglutinated Gaudryina cf. ellisorae and Alabamina midwayensis. Biserial and triserial hyaline taxa and the porcelaneous Spiroloculina sp. are most susceptible to dissolution, whereas rotaliines, such as Cibicidoides and Anomalinoides have an intermediate susceptibility. This implies that mild dissolution of a Midway-type benthic assemblage leads to a relative enrichment in Lenticulina, Gaudryina and rotaliines. Amongst planktic foraminifera, the muricate taxa Acarinina and Morozovella are most resistant, followed by the cancellate Subbotina. The smooth and generally small Globanomalina and Zeauvigerina are least resistant to dissolution. Our data enable to objectively evaluate various degrees of dissolution in benthic and planktic foraminiferal assemblages retrieved from the lower Paleogene Tethyan outcrops. In this way taphonomic artifacts can be readily distinguished from paleoenvironmental signals affecting the primary composition of the assemblages. More generally, we propose that the combined use of foraminiferal numbers, P/B ratio and relative abundances of non-calcareous agglutinated taxa and Lenticulina may provide a powerful proxy for assessing dissolution in hemipelagic assemblages from Cenozoic and upper Cretaceous continental margins. In order to achieve more robust pre-Quaternary paleoenvironmental reconstructions based on quantitative foraminiferal data, application of dissolution proxies, like proposed here, or in slightly modified form, should become a more widely used micropaleontologic procedure. Particularly continental margin studies dealing with major biotic events (e.g. PETM) or employing P/B ratios for sea-level reconstructions should benefit from such an approach.     

Invasion of amphisteginid foraminifera in the Adriatic Sea

Amphisteginid foraminifera are larger symbiont-bearing foraminifera that are abundant in tropical and subtropical reef and shelf regions of the world’s oceans. There is now unequivocal evidence that climate change has led to an expansion of tropical belts. As temperatures rise, surface isotherms are shifting poleward and habitat ranges are moving towards higher latitudes. Fueled by substantial warming, the Mediterranean has been identified as one of the most severely affected areas. This study documents for the first time that amphisteginid foraminifera have now crossed the Strait of Otranto and invaded the eastern Adriatic coast along southern Albania. Sampling on the opposite side along the southern part of the Italian boot shows, however, that amphisteginid foraminifera have not yet colonized the western coast of the Adriatic. The asymmetric invasion of the Adriatic displays spatial heterogeneity, where the progressive colonization follows the major surface currents with a northerly flow along the eastern coast and a southerly return along the western coastline. Previous sampling along Ionian Sea sample sites provides a baseline chronology allowing computations of range expansion rates. The observed recent rate of range expansion in Amphistegina is computed between 4.0 and 10 km/year^?1 and provides strong support for current species model projections. Based on the new data, the range boundary shift is projected to lead to a total northward range expansion of 5.2° latitude in the year 2100. The latitudinal range extension computed for the Mediterranean is thus almost twice as large as those computed for the southern hemisphere. The ongoing range extension into new areas of the Mediterranean Sea is shown to trigger changes in community structures with potential consequences for ecosystem functioning. Numerical abundances and impacts of invasive amphisteginids are greatest at shallow depths <20 m. Evidence is now accumulating that the invasion of amphisteginid foraminifera results in (1) a loss of benthic foraminiferal biodiversity, (2) alterations of foraminiferal community structures and (3) shifts in abundances of functional groups of foraminifera.     

Microfossil assemblages and relative sea-level fluctuations in a lagoon at the Oxfordian/Kimmeridgian boundary (Upper Jurassic) in the eastern part of the Paris Basin

The Late Oxfordian–Early Kimmeridgian interval of the eastern part of the Paris Basin is characterized by a carbonate succession deposited in shallow-marine platform environments. The Gudmont-Villiers section is represented by deposits ranging from barrier to typical lagoonal environments often poor in macrofossils. Previously unpublished calcareous microfossils are more abundant and provide alternative paleoenvironmental indicators. They also provide a biostratigraphical framework across the Oxfordian–Kimmeridgian boundary. The evolution of microfossil associations (algae and benthic foraminifera) in the lower part of the section, based on statistical analyses, is correlated to the sea-level variations. The first highly diversified association composed of small agglutinated and calcitic foraminifera (miliolids, textulariids, Spirillina, Trocholina, Molherina basiliensis etc.) characterizes high sea-level deposits; a second association richer in large agglutinated foraminifera (Alveosepta jaccardi, Everticyclammina, Nautiloculina oolithica) is significantly abundant in low sea-level deposits. A third association characterizes beds with a significant occurrence of encrusting microorganisms and algae (Lithocodium aggregatum, Troglotella incrustans, Cayeuxia piae, dasycladaceans). The upper part of the section is marked by more argillaceous beds and by the occurrence of one opportunist taxon (Lenticulina). This study shows that the microfauna-flora evolution in an internal carbonate platform environment constitute an efficient tool to determine variations in the relative sea level.     

Soft-walled monothalamids (Rhizaria: foraminifera) of the Crimean shelf (Black Sea): taxonomic composition and inter-regional patterns of species diversity and distribution

We present new data on monothalamous (single-chambered) foraminifera from the Black Sea Crimean shelf zone between Karkinitsky Gulf in the west to the area near Kerch in the east. Within this region we recognized a total of 40 morphospecies; 8 are assigned, in some cases tentatively, to known species and another 9 to known genera, again sometimes tentatively. Twelve species (all undescribed) are reported here for the first time. The most abundant species are Psammophaga sp. (sensu Gooday et al. 2011), Goodayia rostellata Sergeeva & Anikeeva 2008 and Vellaria pellucida Gooday & Fernando 1992, each of which is evenly distributed in all studied areas. The highest species richness of monothalamous foraminifera was observed in the Yalta region. Based on a multivariate analysis of monothalamid assemblage structure and diversity indices [Shannon (H’), Margalef (D’), eveness Pielou (J’), Simpson (1-λ’) and rarefaction ES(n)], we recognized three groups of stations, corresponding to the Western, Southern and Eastern coasts of the Crimean peninsula. The monothalamid assemblages found in each of these coastal regions exhibit different structural features and are distinguished by certain characteristic species.