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Though the morphological discrimination of the three pseudo-cryptic Ammonia species, A. aberdoveyensis, A. confertitesta and A. veneta, has been recently established, information on their ecology and habitats are still relatively scarce. This study aims to define distribution patterns of these species at eight sites scattered along the French coasts of the English Channel, over a total of 39 stations. These sites were classified into two habitats, either harbours (heavily modified sites) or less impacted (moderately influenced sites). The use of IndVal index (an index based on how a species is statistically specific to a habitat) clearly indicates that A. confertitesta is recorded preferentially in or close to harbours. Considering its non-indigenous species (NIS) status in Europe, we investigated its reported occurrences in Europe in the literature. It almost always showed a proximity to major European harbours. Sometimes, this species occurred relatively far away from these harbours, suggesting a secondary spread. Finally, this work interprets A. confertitesta being a NIS in the eastern English Channel with assumptions of being invasive regarding its dominance over the indigenous species A. aberdoveyensis and A. veneta. Complementary works such as retrospective core studies of fossil faunas are needed to quantitatively assess when and where A. confertitesta was introduced in Europe and potentially started to replace its congenerics A. veneta and A. aberdoveyensis. [ABSTRACT FROM AUTHOR]

The invasive benthic foraminifera Trochammina hadai has been found for the first time in Europe along the coast of Normandy. Its native range of distribution is in Asia (Japan and Korea), and it has also been introduced along the coasts of western North America, Brazil and Australia. Morphological and molecular assessments confirm that specimens found in Le Havre and Caen-Ouistreham harbors belong to the Asiatic type. Like in Asia, T. hadai was found in transitional waters with muddy sediments. It exhibited high relative abundances (up to about 40%) confirming that T. hadai is a highly competitive species. In the present study, it was nearly absent from natural transitional waters and very abundant in heavily modified habitats like harbors, suggesting that ballast waters may likely be the vector of introduction. It was not recorded farther north along the coast of the Hauts-de-France. It is further hypothesized that the finding of a few specimens outside the harbor may facilitate the expansion of T. hadai in the English Channel by means of propagules dispersion. [ABSTRACT FROM AUTHOR]

We describe a new agglutinated monothalamous foraminiferal species, Capsammina crassa sp. nov., based on integrated observations of the test morphology and the chemical characteristics of materials composing the test. The new species was found at a depth of <60 m on the East coast of Korea. The test morphology is typical of the genus Capsammina, comprising two or more mica plates with a ring of finely agglutinated mineral grains sandwiched between them and surrounding the cell body. There is no distinct test aperture. Elemental analyses of the agglutinated grains revealed 15 different types of mineral grains of which quartz is the most abundant. The surface areas of grains exposed on fractured surfaces ranged from 1.6 to 7,700 µm² and the large plate-like grains forming the upper and lower surfaces measured about 420-2,350 µm in maximum width. The new species is morphologically similar to C. patelliformis, however, the differences in size, distribution area and depth support that these two species are distinct. This discovery is the first record of the genus Capsammina from the North Pacific. Therefore, it extends the biodiversity and geographical distribution of the genus Capsammina, which has been reported only from the bathyal NE Atlantic. Our finding also suggests the possibility of additional discovery of monothalamous foraminifera from around Korea. [ABSTRACT FROM AUTHOR]

Chemical maps and images were made of the test of Textularia earlandi, an agglutinated foraminifera, by ESEM-EDS (Environmental Scanning Electron Microscopy-Energy Dispersive Spectrometer). The specimen is about 300µm long, comprising 17 imbricated growth chambers. In order to evaluate themass distribution along the test, mineral grain densities, as deduced through chemical mapping, as well as the volumes of 650 grains, were treated by geostatistical methods. The volume of the imbricated spheres was 3D-modelled using theMonte-Carlo method. It is calculated that the volume of the chamber grows regularly. The mass of the chambers undergo some variation due to occurrence of various proportions of minerals with different densities. The mass distribution within each chamber is smoothly distributed. Further development on other protists with various shape and geometry could be easily imagined. [ABSTRACT FROM AUTHOR]

The benthic foraminiferal assemblages in Lake Varano (southern Italy) have been investigated in detail. Statistical analyses enable us to recognize two main biotopes and five sub-biotopes that reflect different ecological and environmental conditions. The assemblages mainly seem to be influenced by the hydrological (namely salinity) and sediment conditions in the lake. These biotopes are characterized by specific sub-assemblages and variations in relative species' abundances. The Outer Lake Biotope is affected by marine influence and is dominated by the foraminiferal species: Ammonia beccarii, Ammonia parkinsoniana and Aubignyna perlucida, which are more common in open water environments. In contrast, the Inner-Marginal Lake Biotope reflects more restricted conditions where low salinity values and sand are associated with high numbers of miliolids. These two main biotopes are thus subjected to different degrees of confinement and water residence times, both of which are related to the water exchange time of the lake with the Adriatic Sea. In addition five sub-biotopes (Intermediate Marine, Mixing, "Urban", Marginal, and Innermost) represented by particular foraminiferal assemblages are identified that characterize particular sub-environments. These sub-biotopes are, to some extent, separated by salinity gradients as well as the grain-size and the organic matter of sediments. [ABSTRACT FROM AUTHOR]