The rapid growth of the salmon industry necessitates the development of fast and accurate tools t... more The rapid growth of the salmon industry necessitates the development of fast and accurate tools to assess its environmental impact. Macrobenthic monitoring is commonly used to measure the impact of organic enrichment associated with salmon farm activities. However, classical benthic monitoring can hardly answer the rapidly growing demand because the morphological identification of macro-invertebrates is time-consuming, expensive and requires taxonomic expertise. Environmental DNA (eDNA) metabarcoding of meiofauna-sized organisms, such as Foraminifera, was proposed to overcome the drawbacks of macrofauna-based benthic monitoring. Here, we tested the application of foraminiferal metabarcoding to benthic monitoring of salmon farms in Norway. We analysed 140 samples of eDNA and environmental RNA (eRNA) extracted from surface sediment samples collected at 4 salmon farming sites in Norway. We sequenced the variable region 37f of the 18S rRNA gene specific to Foraminifera. We compared our data to the results of macrofaunal surveys of the same sites and tested the congruence between various diversity indices inferred from metabarcoding and morphological data. The results of our study confirm the usefulness of Foraminifera as bioindicators of organic enrichment associated with salmon farming. The foraminiferal diversity increased with the distance to fish cages, and metabarcoding provides an assessment of the ecological quality comparable to the morphological analyses. The foraminiferal metabarcoding approach appears to be a promising alternative to classical benthic monitoring, providing a solution to the morpho-taxonomic bottleneck of macrofaunal surveys.
FIGURE 5. Leptammina flavofusca gen. et sp. nov. A. Section through entire individual with nucleu... more FIGURE 5. Leptammina flavofusca gen. et sp. nov. A. Section through entire individual with nucleus, nucleoli, nuclear vacuole and exonuclear vacuole. B. Longitudinal section of aperture with peduncular sheath, agglutinated test material and inner organic lining. C. Section through nucleus and exonuclear vacuole, but without nuclear vacuole. D. Longitudinal section of Scale bars = 100 µm.
Deep-sea sediments represent the largest but least known ecosystem on earth. With increasing anth... more Deep-sea sediments represent the largest but least known ecosystem on earth. With increasing anthropogenic pressure, it is now a matter of urgency to improve our understanding of deep-sea biodiversity. Traditional morpho-taxonomic studies suggest that the ocean floor hosts extraordinarily diverse benthic communities. However, due to both its remoteness and a lack of expert taxonomists, assessing deep-sea diversity is a very challenging task. Environmental DNA (eDNA) metabarcoding offers a powerful tool to complement morpho-taxonomic studies. Here we use eDNA to assess benthic metazoan diversity in 39 deep-sea sediment samples from bathyal and abyssal depths worldwide. The eDNA dataset was dominated by meiobenthic taxa and we identified all animal phyla commonly found in the deep-sea benthos; yet, the diversity within these phyla remains largely unknown. The large numbers of taxonomically unassigned molecular operational taxonomic units (OTUs) were not equally distributed among phyla, with nematodes and platyhelminthes being the most poorly characterized from a taxonomic perspective. While the data obtained here reveal pronounced heterogeneity and vast amounts of unknown biodiversity in the deep sea, they also expose the difficulties in exploiting metabarcoding datasets resulting from the lack of taxonomic knowledge and appropriate reference databases. Overall, our study demonstrates the promising potential of eDNA metabarcoding to accelerate the assessment of deep-sea biodiversity for pure and applied deep-sea environmental research but also emphasizes the necessity to integrate such new approaches with traditional morphology-based examination of deep-sea organisms.
Abstract Foraminiferans are very common almost everywhere on the sea bottom and many of them infl... more Abstract Foraminiferans are very common almost everywhere on the sea bottom and many of them influence the sediment surface in different ways. Ammonia cf. aomoriensis created a rough sediment surface through their construction of sediment coverings (secondary tests) by the use of pseudopods. Their maximal distance moved in our experiment was 14.4 mm (median = 7.4 mm, standard error = 0.3 mm) during 24 h. The maximal sediment area covered was 21.0 mm 2 (median = 9.6 mm 2, standard error = 0.3 mm 2) during 24 h of incubation. Colchicine (5 μ M in seawater) was experimentally used to destroy the pseudopodia and consequently prevent them to form any sediment structures. Their influence on sediment stability was experimentally studied by using the LABEREX equipment where the shear stress exerted on the sediment surface during the resuspension was controlled. Our study showed that sediment incubated with colchicine and consequently removed pseudopods is more stable than sediment incubated with no colchicine. The activity of pseudopodial network will to some extent increase the sediment stability but simultaneously increase the bottom roughness, which in turn decreases the sediment stability by reducing the thickness of the viscous sublayer. This allows more turbulence close to the bottom and consequently resuspends and destabilizes the sediment. Active pseudopodia can ingest food (bacteria) but destroyed pseudopodia are unable to do this. The latter condition will allow bacterial populations to increase in number and produce more EPS (extracellular polymeric substances) that will stabilize the sediment even more.
Taxonomy of fourteen very little known species of Nodosariinae Ehrenberg, 1838 in Icelandic water... more Taxonomy of fourteen very little known species of Nodosariinae Ehrenberg, 1838 in Icelandic waters is revised. Knowledge of these species in the North Atlantic relies mainly on studies in the late 19th and early 20th centuries, using large volume samplers. Later studies have emphasized quantitative samples of a few cm3 where the Nodosariinae are very rare. This study analysed 879 dredging samples where Nodosariinae occurred in 492 samples, comprising 7598 specimens of about 415 000 of all picked foraminifera. Ordination analysis of species distributions reflects prominent temperature and salinity differences that exist in the sampling area (753 000 km2) north and south of the Greenland-Scotland Ridge (GSR). Eight species are restricted to southern temperate waters (> 2°C): Dentalina mutabilis (Costa, 1855), Dentalina antarctica Parr, 1950, Dentalina antennula d’Orbigny, 1846, Dentalina filiformis (d’Orbigny, 1826), Grigelis pyrula (d’Orbigny, 1826), Grigelis guttifera (d’Orbigny,...
GROMIA MARMOREA SP. NOV. (FIGS 2–4) <i>Diagnosis:</i> species of <i>Gromia</... more GROMIA MARMOREA SP. NOV. (FIGS 2–4) <i>Diagnosis:</i> species of <i>Gromia</i> with a rounded test, which is spherical, to droplet-shaped, to ovoid in shape; diameter 1.0– 3.4 mm, length: width ratio 0.6– 1.9. Overall colour in fresh specimens, greenish with silvery patches, giving marble-like mottling of wall; preserved specimens, brown. Single, prominent, mound-like oral capsule. <i>Type material and locality:</i> The holotype and paratypes are from an EBS deployment at RV <i>Polarstern</i> station 133#2, 62°46.95 <i>′</i> S, 53°1.72 <i>′</i> W, 1584 m water depth, 16th March 2005 (Table 1). They are deposited at the Research Institute and Natural History Museum Senckenberg, Frankfurt am Main. The holotype is catalogued under reg. no. SMF XXVII 7398. The paratypes are catalogued under reg. no. SMF XXVII 7399. The type specimens were extracted from <i>></i> 300-Mm residue and are preserved in 4% ...
Fig. 1. Modiolus cimbricus sp. nov., holotype (shell length 13.3 mm). The upper part of the figur... more Fig. 1. Modiolus cimbricus sp. nov., holotype (shell length 13.3 mm). The upper part of the figure shows the external shell side and the lower part shows the inner side of the valves. Scale bars = 5 mm.
<i> Modiolus cimbricus</i> sp. nov. urn:lsid:zoobank.org:act: FA5D6226-648B-44C5-A5BE... more <i> Modiolus cimbricus</i> sp. nov. urn:lsid:zoobank.org:act: FA5D6226-648B-44C5-A5BE-1E4D0F97BA67 Figs 1–2<i> Mytilus adriaticus</i> – Petersen 1888: 126.<i> Modiola adriatica</i> – Petersen 1893: 71. — Jensen &amp; Spärck 1934: 75. — Jørgensen 1946: 288.<i> Modiolus adriaticus</i> – Muus 1973: 84. — Rasmussen 1973: 272. — Christensen 1978: 49. — Wikander 1981: 73. — Bondesen 1984: 13. — Larsen<i> et al</i>. 2007: 425. Diagnosis Dissoconch shell substance thin and light. Shell shape in lateral aspect somewhat elongated, anteroventrally upturned often approaching a parallelogram, dorsal margin behind umbones straight in adult specimens; shell margin postero-dorsally stretched and narrowly rounded posteriorly, mid-ventrally straight or nearly so. Umbones strongly prosogyrate not much elevated above the dorsal margin. Shell surface with sharp growth lines and often with low and uneven commarginal ribs. Periostracum yellowish and varnished turning brownish in larger specimens. Short and simple byssal hairs on the periostracum occur mainly around the siphonal region. They are easily lost just as are grains glued to the shell. Shell inside glossy, neither adductor muscle scars nor pallial line are discernible. Ligament is sub-internal, not strong and its length between 35–40% of the adult shell length. The prodissoconch I is 400 µm. The species is edentulous after the nepioconch stage. The nepioconch usually turns whitish when it remains in adult specimens. Largest diameter of nepioconch is most often between 0.6–0.8 mm. Shell colouration varies greatly. Red only, red with blue (violet or purple), blue only, and presence of opaque white, usually as blotches, or absence of white. Red is by far the most common colour expressed as rays, strongest dorsally and posteriorly on the shell. Uncoloured specimens appear to be very rare. A well-developed bundle of byssus, strong, hair-like protein threads, originate from the posterior end of the foot and are used for attachment to sandgrains that form a covering around the shell. [...]
Mass occurrence of seven species of Synaptula (S. sp., S. lamperti, S. madreporica, S. media, S. ... more Mass occurrence of seven species of Synaptula (S. sp., S. lamperti, S. madreporica, S. media, S. psara, S. violacea, and S. virgata) was found on large sponges in the Andaman Sea and Gulf of Thailand. From 1 up to at least 1,000 holothuroids could be found on the pinakoderm of a single sponge, but never in the spongocoel even if it was open and very large. The observed holothuroids remained at the same spot all the time. Sometimes they fed on detritus on the sponge surface. We hypothesize that they also take up nutrients that leak out of the sponge on which they thrive.
Species of large, testate, rhizarian protists in the genus Gromia are often common in high-latitu... more Species of large, testate, rhizarian protists in the genus Gromia are often common in high-latitude coastal environments, including fjords, but are frequently overlooked and almost all are undescribed. Here, we describe three new gromiid species from the Nuuk fjord system on the west coast of southern Greenland. Morphologically, the new species differ in the size and shape of the test. Gromia cucumiformis sp. nov. is elongate, up to 5.5 mm long, with a length:width (L/W) ratio of 4.3–5.5; Gromia botelliformis sp. nov. is up to 2.1 mm long, with a L/W ratio of 3.0–4.8; Gromia brevis is typically less than 1.0 mm long, with a L/W ratio around 2.0. Genetically, they are well-characterised and split between two clades. Gromia cucumiformis and G. brevis branch with several species of deep-water gromiids from the Arabian Sea and the Weddell Sea, while G. botelliformis branches with deep Weddell Sea species and several unnamed and morphologically uncharacterised gromiids from different parts of the world. Gromia botelliformis and G. brevis are currently known only from the Nuuk fjords, but sequences of G. cucumiformis from Greenland group together with sequences from Svalbard and the White Sea. Our genetic data reveal four additional clades of undescribed Gromia species. One contains sequences from Greenland, Svalbard and the White Sea, two comprises sequence from Greenland and the White Sea and one is limited to sequences from Greenland. These results demonstrate the high genetic diversity of gromiids and their widespread distribution in Arctic as well as in deep-sea environments.
Small usually beautifully coloured mussels from the Kattegat were to date identified as Modiolus ... more Small usually beautifully coloured mussels from the Kattegat were to date identified as Modiolus adriaticus (Lamarck, 1819) since C.G.Johs. Petersen’s account of the shell-bearing molluscs was published in 1888. However, these mussels from Danish and Swedish waters represent a very distinct new species which also is endemic. The present paper serves to describe this new species, Modiolus cimbricus sp. nov., which belongs to the genus Modiolus Lamarck, 1799. The genus Gibbomodiola Sacco, 1898, to which Modiolus adriaticus has been moved, is here synonymized with Modiolus Lamarck, 1799.
We describe two new species of spherical single-chambered ('saccamminid') foraminifera fr... more We describe two new species of spherical single-chambered ('saccamminid') foraminifera from the bathyal and abyssal Weddell Sea (Southern Ocean), collected in epibenthic sledge and Agassiz trawl samples obtained during the 2005 ANDEEP III campaign. Both are assigned to Leptammina gen. nov. The new genus is similar in overall test morphology to Saccammina Carpenter, 1869; it is distinguished mainly by its test wall, which is delicate, flexible and composed of fine mineral grains, rather than being rigid and coarsely agglutinated. In Leptammina grisea gen. et sp. nov., the test wall is relatively thick, grayish with a violet tinge and a dull surface; the cytoplasm is dark greenish. In Leptammina flavofusca gen. et sp. nov., the test is yellowish brown, with a very finely, almost transluscent agglutinated wall; the cytoplasm is pale yellowish. Both species have prominent circular apertures. Maximum likelihood phylogenetic analysis of SSU rRNA gene data showed that both species ...
The rapid growth of the salmon industry necessitates the development of fast and accurate tools t... more The rapid growth of the salmon industry necessitates the development of fast and accurate tools to assess its environmental impact. Macrobenthic monitoring is commonly used to measure the impact of organic enrichment associated with salmon farm activities. However, classical benthic monitoring can hardly answer the rapidly growing demand because the morphological identification of macro-invertebrates is time-consuming, expensive and requires taxonomic expertise. Environmental DNA (eDNA) metabarcoding of meiofauna-sized organisms, such as Foraminifera, was proposed to overcome the drawbacks of macrofauna-based benthic monitoring. Here, we tested the application of foraminiferal metabarcoding to benthic monitoring of salmon farms in Norway. We analysed 140 samples of eDNA and environmental RNA (eRNA) extracted from surface sediment samples collected at 4 salmon farming sites in Norway. We sequenced the variable region 37f of the 18S rRNA gene specific to Foraminifera. We compared our data to the results of macrofaunal surveys of the same sites and tested the congruence between various diversity indices inferred from metabarcoding and morphological data. The results of our study confirm the usefulness of Foraminifera as bioindicators of organic enrichment associated with salmon farming. The foraminiferal diversity increased with the distance to fish cages, and metabarcoding provides an assessment of the ecological quality comparable to the morphological analyses. The foraminiferal metabarcoding approach appears to be a promising alternative to classical benthic monitoring, providing a solution to the morpho-taxonomic bottleneck of macrofaunal surveys.
FIGURE 5. Leptammina flavofusca gen. et sp. nov. A. Section through entire individual with nucleu... more FIGURE 5. Leptammina flavofusca gen. et sp. nov. A. Section through entire individual with nucleus, nucleoli, nuclear vacuole and exonuclear vacuole. B. Longitudinal section of aperture with peduncular sheath, agglutinated test material and inner organic lining. C. Section through nucleus and exonuclear vacuole, but without nuclear vacuole. D. Longitudinal section of Scale bars = 100 µm.
Deep-sea sediments represent the largest but least known ecosystem on earth. With increasing anth... more Deep-sea sediments represent the largest but least known ecosystem on earth. With increasing anthropogenic pressure, it is now a matter of urgency to improve our understanding of deep-sea biodiversity. Traditional morpho-taxonomic studies suggest that the ocean floor hosts extraordinarily diverse benthic communities. However, due to both its remoteness and a lack of expert taxonomists, assessing deep-sea diversity is a very challenging task. Environmental DNA (eDNA) metabarcoding offers a powerful tool to complement morpho-taxonomic studies. Here we use eDNA to assess benthic metazoan diversity in 39 deep-sea sediment samples from bathyal and abyssal depths worldwide. The eDNA dataset was dominated by meiobenthic taxa and we identified all animal phyla commonly found in the deep-sea benthos; yet, the diversity within these phyla remains largely unknown. The large numbers of taxonomically unassigned molecular operational taxonomic units (OTUs) were not equally distributed among phyla, with nematodes and platyhelminthes being the most poorly characterized from a taxonomic perspective. While the data obtained here reveal pronounced heterogeneity and vast amounts of unknown biodiversity in the deep sea, they also expose the difficulties in exploiting metabarcoding datasets resulting from the lack of taxonomic knowledge and appropriate reference databases. Overall, our study demonstrates the promising potential of eDNA metabarcoding to accelerate the assessment of deep-sea biodiversity for pure and applied deep-sea environmental research but also emphasizes the necessity to integrate such new approaches with traditional morphology-based examination of deep-sea organisms.
Abstract Foraminiferans are very common almost everywhere on the sea bottom and many of them infl... more Abstract Foraminiferans are very common almost everywhere on the sea bottom and many of them influence the sediment surface in different ways. Ammonia cf. aomoriensis created a rough sediment surface through their construction of sediment coverings (secondary tests) by the use of pseudopods. Their maximal distance moved in our experiment was 14.4 mm (median = 7.4 mm, standard error = 0.3 mm) during 24 h. The maximal sediment area covered was 21.0 mm 2 (median = 9.6 mm 2, standard error = 0.3 mm 2) during 24 h of incubation. Colchicine (5 μ M in seawater) was experimentally used to destroy the pseudopodia and consequently prevent them to form any sediment structures. Their influence on sediment stability was experimentally studied by using the LABEREX equipment where the shear stress exerted on the sediment surface during the resuspension was controlled. Our study showed that sediment incubated with colchicine and consequently removed pseudopods is more stable than sediment incubated with no colchicine. The activity of pseudopodial network will to some extent increase the sediment stability but simultaneously increase the bottom roughness, which in turn decreases the sediment stability by reducing the thickness of the viscous sublayer. This allows more turbulence close to the bottom and consequently resuspends and destabilizes the sediment. Active pseudopodia can ingest food (bacteria) but destroyed pseudopodia are unable to do this. The latter condition will allow bacterial populations to increase in number and produce more EPS (extracellular polymeric substances) that will stabilize the sediment even more.
Taxonomy of fourteen very little known species of Nodosariinae Ehrenberg, 1838 in Icelandic water... more Taxonomy of fourteen very little known species of Nodosariinae Ehrenberg, 1838 in Icelandic waters is revised. Knowledge of these species in the North Atlantic relies mainly on studies in the late 19th and early 20th centuries, using large volume samplers. Later studies have emphasized quantitative samples of a few cm3 where the Nodosariinae are very rare. This study analysed 879 dredging samples where Nodosariinae occurred in 492 samples, comprising 7598 specimens of about 415 000 of all picked foraminifera. Ordination analysis of species distributions reflects prominent temperature and salinity differences that exist in the sampling area (753 000 km2) north and south of the Greenland-Scotland Ridge (GSR). Eight species are restricted to southern temperate waters (> 2°C): Dentalina mutabilis (Costa, 1855), Dentalina antarctica Parr, 1950, Dentalina antennula d’Orbigny, 1846, Dentalina filiformis (d’Orbigny, 1826), Grigelis pyrula (d’Orbigny, 1826), Grigelis guttifera (d’Orbigny,...
GROMIA MARMOREA SP. NOV. (FIGS 2–4) <i>Diagnosis:</i> species of <i>Gromia</... more GROMIA MARMOREA SP. NOV. (FIGS 2–4) <i>Diagnosis:</i> species of <i>Gromia</i> with a rounded test, which is spherical, to droplet-shaped, to ovoid in shape; diameter 1.0– 3.4 mm, length: width ratio 0.6– 1.9. Overall colour in fresh specimens, greenish with silvery patches, giving marble-like mottling of wall; preserved specimens, brown. Single, prominent, mound-like oral capsule. <i>Type material and locality:</i> The holotype and paratypes are from an EBS deployment at RV <i>Polarstern</i> station 133#2, 62°46.95 <i>′</i> S, 53°1.72 <i>′</i> W, 1584 m water depth, 16th March 2005 (Table 1). They are deposited at the Research Institute and Natural History Museum Senckenberg, Frankfurt am Main. The holotype is catalogued under reg. no. SMF XXVII 7398. The paratypes are catalogued under reg. no. SMF XXVII 7399. The type specimens were extracted from <i>></i> 300-Mm residue and are preserved in 4% ...
Fig. 1. Modiolus cimbricus sp. nov., holotype (shell length 13.3 mm). The upper part of the figur... more Fig. 1. Modiolus cimbricus sp. nov., holotype (shell length 13.3 mm). The upper part of the figure shows the external shell side and the lower part shows the inner side of the valves. Scale bars = 5 mm.
<i> Modiolus cimbricus</i> sp. nov. urn:lsid:zoobank.org:act: FA5D6226-648B-44C5-A5BE... more <i> Modiolus cimbricus</i> sp. nov. urn:lsid:zoobank.org:act: FA5D6226-648B-44C5-A5BE-1E4D0F97BA67 Figs 1–2<i> Mytilus adriaticus</i> – Petersen 1888: 126.<i> Modiola adriatica</i> – Petersen 1893: 71. — Jensen &amp; Spärck 1934: 75. — Jørgensen 1946: 288.<i> Modiolus adriaticus</i> – Muus 1973: 84. — Rasmussen 1973: 272. — Christensen 1978: 49. — Wikander 1981: 73. — Bondesen 1984: 13. — Larsen<i> et al</i>. 2007: 425. Diagnosis Dissoconch shell substance thin and light. Shell shape in lateral aspect somewhat elongated, anteroventrally upturned often approaching a parallelogram, dorsal margin behind umbones straight in adult specimens; shell margin postero-dorsally stretched and narrowly rounded posteriorly, mid-ventrally straight or nearly so. Umbones strongly prosogyrate not much elevated above the dorsal margin. Shell surface with sharp growth lines and often with low and uneven commarginal ribs. Periostracum yellowish and varnished turning brownish in larger specimens. Short and simple byssal hairs on the periostracum occur mainly around the siphonal region. They are easily lost just as are grains glued to the shell. Shell inside glossy, neither adductor muscle scars nor pallial line are discernible. Ligament is sub-internal, not strong and its length between 35–40% of the adult shell length. The prodissoconch I is 400 µm. The species is edentulous after the nepioconch stage. The nepioconch usually turns whitish when it remains in adult specimens. Largest diameter of nepioconch is most often between 0.6–0.8 mm. Shell colouration varies greatly. Red only, red with blue (violet or purple), blue only, and presence of opaque white, usually as blotches, or absence of white. Red is by far the most common colour expressed as rays, strongest dorsally and posteriorly on the shell. Uncoloured specimens appear to be very rare. A well-developed bundle of byssus, strong, hair-like protein threads, originate from the posterior end of the foot and are used for attachment to sandgrains that form a covering around the shell. [...]
Mass occurrence of seven species of Synaptula (S. sp., S. lamperti, S. madreporica, S. media, S. ... more Mass occurrence of seven species of Synaptula (S. sp., S. lamperti, S. madreporica, S. media, S. psara, S. violacea, and S. virgata) was found on large sponges in the Andaman Sea and Gulf of Thailand. From 1 up to at least 1,000 holothuroids could be found on the pinakoderm of a single sponge, but never in the spongocoel even if it was open and very large. The observed holothuroids remained at the same spot all the time. Sometimes they fed on detritus on the sponge surface. We hypothesize that they also take up nutrients that leak out of the sponge on which they thrive.
Species of large, testate, rhizarian protists in the genus Gromia are often common in high-latitu... more Species of large, testate, rhizarian protists in the genus Gromia are often common in high-latitude coastal environments, including fjords, but are frequently overlooked and almost all are undescribed. Here, we describe three new gromiid species from the Nuuk fjord system on the west coast of southern Greenland. Morphologically, the new species differ in the size and shape of the test. Gromia cucumiformis sp. nov. is elongate, up to 5.5 mm long, with a length:width (L/W) ratio of 4.3–5.5; Gromia botelliformis sp. nov. is up to 2.1 mm long, with a L/W ratio of 3.0–4.8; Gromia brevis is typically less than 1.0 mm long, with a L/W ratio around 2.0. Genetically, they are well-characterised and split between two clades. Gromia cucumiformis and G. brevis branch with several species of deep-water gromiids from the Arabian Sea and the Weddell Sea, while G. botelliformis branches with deep Weddell Sea species and several unnamed and morphologically uncharacterised gromiids from different parts of the world. Gromia botelliformis and G. brevis are currently known only from the Nuuk fjords, but sequences of G. cucumiformis from Greenland group together with sequences from Svalbard and the White Sea. Our genetic data reveal four additional clades of undescribed Gromia species. One contains sequences from Greenland, Svalbard and the White Sea, two comprises sequence from Greenland and the White Sea and one is limited to sequences from Greenland. These results demonstrate the high genetic diversity of gromiids and their widespread distribution in Arctic as well as in deep-sea environments.
Small usually beautifully coloured mussels from the Kattegat were to date identified as Modiolus ... more Small usually beautifully coloured mussels from the Kattegat were to date identified as Modiolus adriaticus (Lamarck, 1819) since C.G.Johs. Petersen’s account of the shell-bearing molluscs was published in 1888. However, these mussels from Danish and Swedish waters represent a very distinct new species which also is endemic. The present paper serves to describe this new species, Modiolus cimbricus sp. nov., which belongs to the genus Modiolus Lamarck, 1799. The genus Gibbomodiola Sacco, 1898, to which Modiolus adriaticus has been moved, is here synonymized with Modiolus Lamarck, 1799.
We describe two new species of spherical single-chambered ('saccamminid') foraminifera fr... more We describe two new species of spherical single-chambered ('saccamminid') foraminifera from the bathyal and abyssal Weddell Sea (Southern Ocean), collected in epibenthic sledge and Agassiz trawl samples obtained during the 2005 ANDEEP III campaign. Both are assigned to Leptammina gen. nov. The new genus is similar in overall test morphology to Saccammina Carpenter, 1869; it is distinguished mainly by its test wall, which is delicate, flexible and composed of fine mineral grains, rather than being rigid and coarsely agglutinated. In Leptammina grisea gen. et sp. nov., the test wall is relatively thick, grayish with a violet tinge and a dull surface; the cytoplasm is dark greenish. In Leptammina flavofusca gen. et sp. nov., the test is yellowish brown, with a very finely, almost transluscent agglutinated wall; the cytoplasm is pale yellowish. Both species have prominent circular apertures. Maximum likelihood phylogenetic analysis of SSU rRNA gene data showed that both species ...
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