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Deep-sea Cibicidoides pachyderma (forma mundulus) and related Cibicidoides spp. were cultured at in situ pressure for 1–2 d, or 6 weeks to 3 months. During that period, fluorescence analyses following BCECF-AM (2′,7′-bis(2-carboxyethyl)-5-(and-6)-carboxyfluorescein acetoxymethyl ester) or calcein (bis[N,N-bis(carboxymethyl)aminomethyl]-fluorescein) labelling revealed a persisting cytoplasmic sheet or envelope surrounding the Cibicidoides tests. Thus, the Cibicidoides shell can be considered as an internal rather than an external cell structure. A couple of days to a week after being transferred into high-pressure aquaria and adjusted to a pressure of 115 bar, the foraminifera changed from a mobile to a more or less sessile living mode. During this quasi-sessile way of life, a series of comparably thick static ectoplasmic structures developed that were not resorbed or remodelled but, except for occasional further growth, remained unchanged throughout the experiments. Three different types of these permanent structures were observed. (a) Ectoplasmic “roots” were common in adult C. pachyderma, C. lobatulus, and C. wuellerstorfi specimens. In our experiments single ectoplasmic roots grew to a maximum of 700 times the individuals' shell diameter and were presumably used to anchor the specimen in an environment with strong currents. (b) Ectoplasmic “trees” describe rigid ectoplasmic structures directed into the aquarium's water body and were used by the foraminifera to climb up and down these ectoplasmic structures. Ectoplasmic trees have so far only been observed in C. pachyderma and enabled the tree-forming foraminifera to elevate itself above ground. (c) Ectoplasmic “twigs” were used to guide and hold the more delicate pseudopodial network when distributed into prevailing currents and were, in our experiments, also only developed in C. pachyderma specimens. Relocation of a specimen usually required it to tear apart and leave behind the rigid ectoplasmic structures and eventually also the envelope surrounding the test. Apparently, these rigid structures could not be resorbed or reused.

The fauna of benthic foraminifers from the northern Laptev Sea has been analyzed to identify the relationship between the distribution of benthic foraminifers and environmental conditions in the eastern and western parts of the sea. The abundance of benthic foraminifer tests in the Laptev Sea is universally low, no more than 3–9 ind./g. Greater foraminifer abundances were found in the west, on the shelf of the Vilkitsky Strait. Foraminifers with agglutinated tests were dominant, 77–100%. In the east, the assemblages consisted almost entirely of agglutinated tests (90–100%). Calcareous Melonis barleeanus was common, up to 10–15%, on the shelf and the continental slope in the western part of the sea. Small specimens of the polar planktic species Neogloboquadrina pachyderma sin occurred. In one sample at an abyssal water depth of 2996 m, the abundance of its tests increased to 302 ind./g; the assemblage was composed predominantly of N. pachyderma sin., both small (juvenile) and large (adult) individuals with good preservation. The massive presence of the polar species N. pachyderma sin. at an abyssal depth in the eastern region indicates the dominant influence of Arctic waters there.

Isotopic and trace-element signals in the calcite shells of the planktonic foraminifera Neogloboquadrina pachyderma represent key proxies to reconstruct past climatic conditions in northern high latitudes. A correct interpretation of these chemical signals requires knowledge of the habitat and trophic interactions of the species. Direct observations on the biological interactions of N. pachyderma in polar environments are lacking and to date no consensus exists on the trophic behavior of this species. Here, we use single-cell metabarcoding to characterize the interactions of 39 specimens of N. pachyderma from two sites in the Baffin Bay with the local eukaryotic pelagic community. Our results show that the eukaryotic interactome of the foraminifera is dominated by diatoms, accounting for >50% of the reads in 17 of the samples, but other groups such as Crustacea and Syndiniales are also present. The high abundance Syndiniales suggests that these parasites could infect N. pachyderma and may play an important role in its population dynamics. Moreover, the strong but taxonomically non-specific association with algae, existing irrespective of depth and occurring in specimens collected far below the photic zone indicates that opportunistically grazed diatom-fueled marine aggregates likely represent the main interaction substrate of N. pachyderma.

Henricia specimens were collected using fishing nets from the East Sea of Korea. The specimens were identified as Henricia oculata Pennant, 1777, belonging to the family Echinasteridae of the order Spinulosida. This species can be distinguished from other Henricia species by broad arms (R/r=4-4.1), rough skin, a thick arm base, three to nine minute delicate abactinal spines, and inferomarginal plates reniform in shape. This species superficially resembles H. pachyderma in its body size and wide papular areas but differs mainly in the number of papulae and abactinal spines, and the shape and arrangement of the inferomarginal plates. To date, two genera of Echinasteridae, Aleutihenricia and Henricia, with a total of 13 species, have been reported in Korea. The morphological characteristics of H. oculata are described, and photographs are provided.

Sea stars were collected from the adjacent waters of Jukbyeon and Jumunjin, Korea, using fishing nets at depths of 70-100 m. The specimens were identified as Henricia perforata (O.F. Muller, 1776) in the family Echinasteridae and order Spinulosida, with worldwide species distribution. H. perforata can be distinguished from some morphologically related Henricia species by its long, slender, and pointed adambulacral spines. The abactinal skeleton of H. perforata has wide papular areas resembling those of H. pachyderma, but the former has more papulae (two to seven). Previously, two genera of Echinasteridae, Aleutihenricia and Henricia, with a total of 12 echinasterid species, have been reported in Korea. The morphological characteristics of H. perforata are described and photographs are provided.

Changeover from a glacial to an interglacial climate is considered as transitional between two stable modes. Palaeoceanographic reconstructions using the polar foraminifera Neogloboquadrina pachyderma highlight the retreat of the Polar Front during the last deglaciation in terms of both its decreasing abundance and stable oxygen isotope values (δ18O) in sediment cores. While conventional isotope analysis of pooled N. pachyderma and G. bulloides shells shows a warming trend concurrent with the retreating ice, new single-shell measurements reveal that this trend is composed of two isotopically different populations that are morphologically indistinguishable. Using modern time series as analogues for interpreting downcore data, glacial productivity in the mid-North Atlantic appears limited to a single maximum in late summer, followed by the melting of drifting icebergs and winter sea ice. Despite collapsing ice sheets and global warming during the deglaciation, a second “warm” population of N. pachyderma appears in a bimodal seasonal succession, separated by the subpolar G. bulloides. This represents a shift in the timing of the main plankton bloom from late to early summer in a “deglacial” intermediate mode that persisted from the glacial maximum until the start of the Holocene. When seawater temperatures exceeded the threshold values, first the “cold” (glacial) then the “warm” (deglacial) populations of N. pachyderma disappeared, whilst G. bulloides with a greater tolerance to higher temperatures persisted throughout the Holocene to the present day in the midlatitude North Atlantic. Single-specimen δ18O of polar N. pachyderma reveals a steeper rate of ocean warming during the last deglaciation than appears from conventional pooled δ18O average values.

Individual foraminifera analysis (IFA) holds promise to reconstruct seasonal to interannual oceanographic variability. Even though planktonic foraminifera are reliable recorders of environmental conditions on a population level, whether they also are on the level of individuals is unknown. Yet, one of the main assumptions underlying IFA is that each specimen records ocean conditions with negligible noise. Here we test this assumption using stable isotope data measured on groups of four shells of Neogloboquadrina pachyderma from a 16–19 d resolution sediment trap time series from the subpolar North Atlantic. We find a within-sample variability of 0.11 ‰ and 0.10 ‰ for δ18O and δ13C respectively that shows no seasonal pattern and exceeds water column variability in spring when conditions are homogeneous down to hundreds of metres. We assess the possible effect of life cycle characteristics and delay due to settling on foraminifera δ18O variability with simulations using temperature and δ18Oseawater as input. These simulations indicate that the observed δ18O variability can only partially be explained by environmental variability. Individual N. pachyderma are thus imperfect recorders of temperature and δ18Oseawater. Based on these simulations, we estimate the excess noise on δ18O to be 0.11±0.06 ‰. The origin and nature of the recording imprecision require further work, but our analyses highlight the need to take such excess noise into account when interpreting the geochemical variability among individual foraminifera.

Isotopic and trace-element signals in the calcite shells of the planktonic foraminiferaNeogloboquadrina pachydermarepresent key proxies to reconstruct past climatic conditions in northern high latitudes. A correct interpretation of these chemical signals requires knowledge of the habitat and trophic interactions of the species. Direct observations on the biological interactions ofN. pachydermain polar environments are lacking and to date no consensus exists on the trophic behaviour of this species. Here we use single-cell metabarcoding to characterise the interactions of 39 specimens ofN. pachydermafrom two sites in the Baffin Bay with the local eukaryotic pelagic community. Our results show that the eukaryotic interactome of the foraminifera is dominated by diatoms, accounting for > 50% of the reads in 17 of the samples, but other groups such as Crustacea and Syndiniales are also present. The high abundance Syndiniales suggests that these parasites could infectN. pachydermaand may play an important role in its population dynamics. Moreover, the strong but taxonomically non-specific association with algae, existing irrespective of depth and occurring in specimens collected far below the photic zone indicates that opportunistically grazed diatom-fuelled marine aggregates likely represent the main interaction substrate ofN. pachyderma.

Deciphering the evolution of marine plankton is typically based on the study of microfossil groups. Cryptic speciation is common in these groups, and large intragenomic variations occur in ribosomal RNA genes of many morphospecies. In this study, we correlated the distribution of ribosomal amplicon sequence variants (ASVs) with paleoceanographic changes by analyzing the high-throughput sequence data assigned to Neogloboquadrina pachyderma in a 140,000-year-old sediment core from the Arctic Ocean. The sedimentary ancient DNA demonstrated the occurrence of various N. pachyderma ASVs whose occurrence and dominance varied through time. Most remarkable was the striking appearance of ASV18, which was nearly absent in older sediments but became dominant during the last glacial maximum and continues to persist today. Although the molecular ecology of planktonic foraminifera is still poorly known, the analysis of their intragenomic variations through time has the potential to provide new insight into the evolution of marine biodiversity and may lead to the development of new and important paleoceanographic proxies.

Planktonic calcifiers, the foraminiferal species Neogloboquadrina pachyderma and Turborotalita quinqueloba, and the thecosome pteropod Limacina helicina from plankton tows and surface sediments from the northern Barents Sea were studied to assess how shell density varies with depth habitat and ontogenetic processes. The shells were measured using X-ray microcomputed tomography (XMCT) scanning and compared to the physical and chemical properties of the water column including the carbonate chemistry and calcium carbonate saturation of calcite and aragonite. Both living L. helicina and N. pachyderma increased in shell density from the surface to 300 m water depth. Turborotalita quinqueloba increased in shell density to 150–200 m water depth. Deeper than 150 m, T. quinqueloba experienced a loss of density due to internal dissolution, possibly related to gametogenesis. The shell density of recently settled (dead) specimens of planktonic foraminifera from surface sediment samples was compared to the living fauna and showed a large range of dissolution states. This dissolution was not apparent from shell-surface texture, especially for N. pachyderma, which tended to be both thicker and denser than T. quinqueloba. Dissolution lowered the shell density while the thickness of the shell remained intact. Limacina helicina also increase in shell size with water depth and thicken the shell apex with growth. This study demonstrates that the living fauna in this specific area from the Barents Sea did not suffer from dissolution effects. Dissolution occurred after death and after settling on the sea floor. The study also shows that biomonitoring is important for the understanding of the natural variability in shell density of calcifying zooplankton.

Planktonic foraminifera inhabit in the ocean waters and their spatial distribution is driven mainly by surface temperature. Thus, the tests remain deposited in the ocean sediment show different assemblages according to global climate zones. The main goal of this study was to assess the planktonic foraminifera found in the lowest continental slope of Uruguayan Continental Margin (UCM), and to identify the best criteria for future late Quaternary biostratigraphic and paleoceanographic models and based on carbonate preservation to identify water masses changes. For this purpose, this work examines foraminifera within a sediment core (T-90, 372 cm recovery, 3273 m water depth) collected in the lowest slope of UCM using a gravity corer. Forty height samples were selected along the core for foraminifera presence/absence analysis, and 13 samples, in the core section between 20 and 100 cm for foraminiferal faunal census. The age model was based on three AMS 14 C dating. Foraminifera were absent in the core bottom, but were very abundant in its upper part. This variation of foraminifera was associated with fluctuations of lysocline in the glacial/interglacial transition, related to changes in geometry of bottom water masses. The most abundant species were Globorotalia inflata , Neogloboquadrina incompta , Globigerina bulloides , Globorotalia crassaformis , Globigerinoides ruber (white, sensu stricto ) and Neogloboquadrina pachyderma . Principal component analysis (PCA) allowed to distinguished 3 groups of species in terms of climate zones: G. inflata (transicional), N. incompta (subpolar) and N. pachyderma (polar). Cluster analysis also identified three patterns of relative abundance among these three species, which can be related to oscillations in the latitude of Brazil-Malvinas Confluence zone during the last 15 ka. For future studies, it will be possible to check the relationship between these species as indicators of others paleoceanographic events in the study area. Resumo Os foraminiferos planctonicos habitam os oceanos sendo a sua distribuicao espacial influenciada principalmente pela temperatura das aguas de superficie. As suas carapacas depositadas no sedimento oceânico registam diferentes associacoes de acordo com as zonas climaticas globais. O principal objetivo deste trabalho e identificar mudancas de massas de agua, no talude inferior da Margem Continental Uruguaia (UCM), com base na preservacao de carbonatos e nas associacoes de foraminiferos planctonicos. Este trabalho baseia-se no estudo de foraminiferos planctonicos num testemunho de sedimentos (T-90, 372 cm de recuperacao) recolhido a 3273 m de profundidade de lâmina de agua, no talude continental inferior de UCM. Foram selecionadas 40 amostras ao longo do testemunho para analise presenca / ausencia de foraminiferos, e 13 amostras, na secao central entre 20 e 100 cm para o estudo das associacoes de foraminiferos. O modelo de idade foi baseado em tres datacoes de radiocarbono por AMS. Os foraminiferos estao ausentes na extremidade inferior do testemunho, mas sao muito abundantes na seccao superior. Esta variacao da abundância de foraminiferos podera estar associada a flutuacoes da lisoclina na transicao glacial/interglacial, relacionadas com mudancas na geometria das massas de agua do fundo. As especies mais abundantes ao longo do testemunho sao Globorotalia inflata , Neogloboquadrina incompta , Globigerina bulloides , Globorotalia crassaformis , Globigerinoides ruber (branco, sensu stricto ) e Neogloboquadrina pachyderma . A analise de componentes principais (PCA) permitiu distinguir 3 grupos de especies em termos de zonas climaticas: G. inflata (transicional), N. incompta (subpolar) e N. pachyderma (polar). A analise de agrupamento permitiu identificar tres padroes de abundância relativa entre essas tres especies, que podem estar relacionadas a oscilacoes na latitude da zona de confluencia Brasil-Malvinas durante os ultimos 15 ka. Estudos futuros, poderao basear-se na relacao entre estas especies para tracar eventos paleoceanograficos na regiao estudada.

The Subtropical Front (STF) is one of the major ocean fronts in the south-west Pacific. The STF migration has a distinct but varying impact on the temperature change throughout the region. To improve our understanding on the history of the STF migration and the relationship between STF migration and global climate change, we have generated a 450-kyr record of sea surface temperature (SST) change at IODP Site U1352 located in the Canterbury Basin off New Zealand. Planktonic foraminiferal assemblages from the site were used to derive SST estimates. Comparisons of the planktonic foraminiferal assemblage and SST record of IODP Site U1352 with those of ODP Site 1119, DSDP Site 594 and core MD06-2986 allow us to reconstruct the spatial change of the STF over the last 450 kyr by locating the positions of its Southland Front (SF) section, which runs nearly parallel to the South Island's shoreline. The percentage of Neogloboquadrina pachyderma in the sum of Nq. pachyderma and Nq. incompta was below 40% at Sites IODP U1352, ODP 1119 and DSDP 594 during Marine Isotope Stage (MIS) 11c, MIS 7a–c and MIS 5e. Moreover, the SSTs of the three sites during these periods were similar and close to that of the present-day. This indicates that the three sites were covered by a Subtropical Water–Subantarctic Water (STW–SAW) mixture during these interglacials. IODP Site U1352 recorded a similar scenario during MIS 7e. In comparison with previous studies, the higher resolution record of IODP Site U1352 showed the influence of an STW–SAW mixture was limited to MIS 11c, MIS 7e, MIS 7a–c and MIS 5e at this site. The SSTs of Sites IODP U1352, ODP 1119 and DSDP 594 were similar during MIS 11a–b and MIS 9a–d. At the same time, the temperature differences among the three sites and core MD06-2986 (west of New Zealand) during MIS 11a–b and MIS 9a–d were larger than during interglacials MIS 11c, MIS 7a–c, and MIS 5e. These indicate that the Subantarctic Water (SAW) influenced Sites IODP U1352, ODP 1119 and DSDP 594 during MIS 11a–b and MIS 9a–d. The ~3–4 °C warmer SSTs at Sites IODP U1352 and ODP 1119 than at DSDP Site 594 suggest that the SF is situated between DSDP Site 594 and Sites IODP U1352, ODP 1119 during MIS 7d and glacial periods of MIS 10, MIS 8, and MIS 6. Hence, unlike previous studies in the region, MIS 7d is identified as a glacial period.

Introduction: Pachydermoperiostosis (PDP) or hypertrophic osteoarthropathy (HOA) is a rare disease that has genetic predisposition and defined clinical features. Aim of the work: To study and analyse the clinical features of Tunisian PDP patients and review the literature. Patients and methods: The PDP cases attending the Rheumatology Department of the University Hospital Farhat Hached of Sousse in Tunisia were retrospectively studied over a period of 17 years (2000–2017). Secondary causes were excluded. Results: The PDP cases had a primary and complete form of the disease and included 6 men at a frequency of 0.03% (6/20,000) of the total number of rheumatic diseases cases attending the rheumatology clinic. The mean age was 27 ± 12.3 years [18–46 years]. Five patients had arthralgia and one polyarthritis. Thickening of the skin of the head and distal extremities (pachyderma) and deep folds and furrows of the skin of the forehead was observed in all cases. Digital clubbing of the fingers and toes and spade-like enlargement of the hands and feet was noted in 5 cases. Hyperhidrosis of the hands and feet was observed in 4 cases and seborrhea in 2. Elevated acute phase reactants were found in 4 cases. Hypergammaglobulinemia was present in one case. Periostosis of the long bones was observed in all cases. Treatment consisted of analgesics in all cases, non-steroidal anti-inflammatory drugs in 2 cases and tamoxifen in 2 cases. Conclusions: Complete form of primary PDP is rarely present among rheumatic diseases patients in Tunisia. A multicenter larger number longitudinal study is recommended. Keywords: Pachydermoperiostosis, Clubbing, Hypertrophic osteoarthropathy, Periostosis

Mg/Ca ratio paleothermometry in foraminifera is an important tool for the reconstruction and interpretation of past environments. However, existing Mg/Ca:temperature relationships for planktic species inhabiting middle- and high-latitude environments are limited by a lack of information about the development and impact of low-Mg/Ca ratio “crusts” and the influence of the carbonate system on Mg/Ca ratios in these groups. To address this, we cultured individual specimens of Neogloboquadrina incompta and Neogloboquadrina pachyderma in seawater across a range of temperature (6°–12°C) and pH (7.4–8.2). We found by laser ablation inductively couple mass spectrometry analyses of shells that culture-grown crust calcite in N. incompta had a lower Mg/Ca ratio than ontogenetic calcite formed at the same temperature, suggesting that temperature is not responsible for the low-Mg/Ca ratio of neogloboquadrinid crusts. The Mg/Ca:temperature relationship for ontogenetic calcite in N. incompta was consistent with the previously published culture-based relationship, and no significant relationship was found between Mg/Ca ratios and pH in this species. However, the Mg/Ca ratio in laboratory-cultured N. pachyderma was much higher than that reported in previous core top and sediment trap samples, due to lack of crust formation in culture. Application of our ontogenetic calcite-specific Mg/Ca:temperature relationships to fossil N. pachyderma and N. incompta from five intervals in cores from the Santa Barbara Basin and the Bering Sea shows that excluding crust calcite in fossil specimens may improve Mg/Ca-based temperature estimates.

Background: Pachyderma is defined as severely thickened skin with deep folds and is occasionally observed with primary cutaneous NK and T-cell lymphoma (pCNKTCL), primary cutaneous B-cell lymphoma (pCBCL), and leukemia cutis (LC). Aim: To describe the clinical, histological, and therapeutic particularities of a series of pCNKTCL, pCBCL, and LC patients with pachyderma. Results: In a series of pCNKTCL (n = 70), pCBCL (n = 12), and LC (n = 2) patients followed up during 9 years, 6 cases of pachyderma were observed. Pachyderma occurred on the arms (n = 2), thighs (n = 1), forehead (n = 1), and face (n = 2). The mean age of the patients was 69 years (51–82). The stages were erythrodermic (T4) mycosis fungoides (MF) (n = 1), folliculotropic MF (FMF) (n = 2), classic (T2) MF (n = 2), and chronic myeloid leukemia (n = 1). The erythrodermic MF patient with acute pachyderma on the right arm responded rapidly to oral steroids. The other cases were indolent, appeared progressively, and were highly treatment resistant. Histology revealed dense dermal neoplastic infiltration. The immunohistological profile of the pachydermic lesions was similar to common MF and LC. Conclusion: Pachyderma is an atypical manifestation of MF and LC and may occur on the face (FMF) or the extremities (MF). The rapidly appearing pachyderma may be transitory and responds readily to oral steroids.

To trace spatial variations in Holocene reservoir ages of surface and subsurface waters we studied narrowly spaced 14C records of planktic foraminifera in three high-sedimentation rate cores from the Nordic Seas, the Barents Sea continental margin and eastern Fram Strait. The two northern cores reveal a distinct Early Holocene 14C plateau in dates on the subsurface dweller Neogloboquadrina pachyderma at 9.3–9.1 14C ka. The plateau was tuned to an atmospheric 14C plateau at 9.0–8.7 14C ka that spans 10.2–9.6 calendar ka. These two plateau boundaries provide robust age control points to estimate short-term changes in sedimentation rate and to correlate paleoceanographic signals over 900 km along the West Spitsbergen Current. The difference between planktic and atmospheric 14C plateau ages suggests local 14C reservoir ages of 370–400 yr. Planktic foraminifera species that inhabit different water masses document different reservoir ages. By comparison, the subpolar N. incompta reveals a reservoir age of 150 yr, probably formed in well-mixed Atlantic-sourced waters during winter. The near-surface dweller Turborotalita quinqueloba shows an age of 290 yr in the Fram Strait, but one of 720 yr at the Barents Sea continental margin. The latter age suggests a calcification within old, meltwater-enriched Arctic surface waters admixed by the East Spitsbergen Current. Likewise, we assign an elevated reservoir age of 760 yr on mixed species at a Norwegian Sea site near 71°N to Preboreal meltwaters that spread from northern Norway far west, also documented by the spatial distribution of a coeval δ13C minimum of N. pachyderma.

Next-generation sequencing was used to obtain the complete mitogenome of Henricia pachyderma (Hayashi, 1940). The mitogenome form was found to be a circular molecule 16,192 bp long with a 5...

Pachydermoperiostosis (Touraine-Solente-Gole Syndrome) is a hereditary disorder which usually presents with bony lesions (periostosis), digital clubbing and skin thickening (pachyderma). Facial coarsening, spade-like hands and feet with increased sweating may cause diagnostic confusion between

Background Pachydermoperiostosis (PDP) is a rare disorder characterized by clubbing of the fingers, thickening of the skin (pachyderma), and excessive sweating (hyperhidrosis). It typically appears during childhood or adolescence, often around the time of puberty, and progresses slowly. Clinical presentations of PDP can be confused with secondary hypertrophic osteoarthropathy, psoriatic arthritis, rheumatoid arthritis, thyroid acropachy, and acromegaly. Case presentation A Mongolian male, aged 19 years, resident of a hilly district of Nepal, with history of consanguinity, presented to our outpatient department with chief complaints of pain and swelling in both hands and feet for 6 years. The pain was insidious in onset, throbbing in nature, and not relieved by over-the-counter medications. The patient also complained of profuse sweating, progressive enlargement of hands and feet, and gradual coarsening of facial features. On examination there were marked skin folds in the forehead, face, and eyelids. Clubbing and swelling of bilateral knee joints and ankle joints was also evident. He was subsequently investigated extensively for acromegaly. Insulin-like growth factor-1 level and oral glucose tolerance test were normal. Radiography of various bones showed periosteal hypertrophy with subperiosteal bone formation. Conclusions PDP should be considered as a differential diagnosis when a patient presents with hypertrophic osteoarthropathy and acromegalic features.

Oxygen and carbon isotope analyses of the foraminifera Orbulina universa (planktic), Uvigerina peregrina (benthic) and Cibicides pachyderma (benthic) in 45 bottom samples from the archipelago of Bocas del Toro, Caribbean Panama, are used to address the reliability of stable isotope values in distinguishing differences among neritic surface water and middle neritic to upper bathyal depths. The significance of variation in isotope values within stations, between stations within depth-defined groups, and between depths was determined with Analysis of Variance. Isotope values differ significantly among stations with few exceptions; thus, within-station error is minimal. δ 18 O values of O. universa across the open shelf are the same. Oxygen isotope ratios of U. peregrina discriminate outer shelf to upper slope depths well. δ 18 O values of C. pachyderma from the inner middle shelf, outer middle shelf, and inner outer shelf are significantly different, and mean values from 33 m to 240 m are strongly correlated with water depth. Cibicides pachyderma from two stations shows strong δ 18 O evidence of downslope transport of 80 and 160 m, corroborated by foraminiferal assemblages. δ 13 C can only differentiate middle shelf and outermost outer shelf to upper slope depths. Oxygen isotope values of O. universa and U. peregrina generally agree with predicted temperatures, and those of C. pachyderma are consistently low. Comparisons of δ 18 O values of benthic and planktic foraminifera, and neritic and deep-sea planktic foraminifera, enable qualitative and even quantitative estimates of paleodepth and paleosalinity, enabling their use in Neogene studies of sedimentary rocks within the region.

The close association between planktic foraminiferal assemblages and local hydrography make foraminifera invaluable proxies for environmental conditions. Modern foraminiferal seasonality is important for interpreting fossil distributions and shell geochemistry as paleoclimate proxies. Understanding this seasonality in an active upwelling area is also critical for anticipating which species may be vulnerable to future changes in upwelling intensity and ocean acidification. Two years (2012–2014) of plankton tows, along with conductivity–temperature–depth profiles and carbonate chemistry measurements taken along the north-central California shelf, offer new insights into the seasonal dynamics of planktic foraminifera in a seasonal coastal upwelling regime. This study finds an upwelling affinity for Neogloboquadrina pachyderma as well as a seasonal and upwelling associated alternation between dominance of N. pachyderma and Neogloboquadrina incompta, consistent with previous observations. Globigerina bulloides, however, shows a strong affinity for non-upwelled waters, in contrast to findings in Southern California where the species is often associated with upwelling. We also find an apparent lunar periodicity in the abundances of all species and document the presence of foraminifera even at very low saturation states of calcite.

Planktic foraminiferal Mg/Ca ratios have become a fundamental seawater temperature proxy in past climate reconstructions, due to the temperature dependence of Mg uptake into foraminiferal calcite. However, empirical calibrations for single species from methodologically consistent data are still lacking. Here we present species-specific calibrations of Mg/Ca versus calcification temperature for two commonly used species of planktic foraminifera: Globigerina bulloides and Neogloboquadrina pachyderma left, based on a series of Southern Ocean and North Atlantic core tops. Combining these new data with previously published data, we derive an integrated G. bulloides Mg/Ca-temperature calibration for mid and high latitudes of both hemispheres between 2 and 18°C, where Mg/Ca = 1.006 ± 0.032 * e0.065 ± 0.003*Tiso (R2 = 0.82). G. bulloides is found to calcify deeper in the Southern Ocean (∼ 200 m) than in the North Atlantic (top 50 m). We also propose a Mg/Ca temperature calibration to describe the temperature response in N. pachyderma left that calcified away from the influence of sea ice in the Southern Ocean, valid between ∼ −1 and 9°C, of the form Mg/Ca = 0.580 ± 0.016 * e0.084 ± 0.006*Tiso (R2 = 0.70). These calibrations account for uncertainties on Mg/Ca measurements and calcification temperature that were carefully estimated and propagated using Monte Carlo iterations. The 1σ propagated error in Mg/Ca-derived temperatures is 1.1°C for G. bulloides and 0.9°C for N. pachyderma left for the presented data sets. Geographical extension of genotypes must be assessed when choosing to develop regional or global calibrations.

IODP Site U1340 and Site U1343 in the Bering Sea have been investigated with regard to planktonic foraminifers and fragmentation. The base of Site U1340 dates back to the Early Pliocene and the base of Site U1343 to the Early Pleistocene. Site U1340 is situated at Bowers Ridge, the southern Bering Sea. Site U1343 is situated near the gateway to the Arctic Ocean in the northern Bering Sea. At both sites there are none or very few planktonic foraminifers during the Pliocene and early Pleistocene. After 1.3–1.4 Ma the planktonic foraminifers are continuously present for most of the samples examined. Three stratigraphic events have been identified in this study. The first occurrence (FO) of Neogloboquadrina inglei is observed at 1.4–1.5 Ma, although this event may be affected by poor preservation of foraminifers in older sediments. The observed age of the change in the coiling ratio of Neogloboquadrina pachyderma from right to left at 1.2 Ma agrees with the dating of the same event at the Californian margin. The age of the last occurrence (LO) of N. inglei also seems to match the same event from the Californian margin at 0.7 Ma. This implies that these events are robust regional events for the entire northern Pacific. Multivariate analyses of the quantitative planktonic foraminifer data show three main faunal assemblages. The oldest assemblage from 1.3–1.4 Ma to 1.2 Ma is dominated by N pachyderma s.l. (dex) together with Globigerina bulloides . Other species in this fauna are N. inglei , N. pachyderma s.l. (sin), Globigerina umbilicata and Turborotalita quinqueloba. After 1.2 Ma the faunal assemblage is dominated by N. pachyderma s.l. (sin), but the remaining species are the same as before. At 0.7 Ma N. inglei disappears, whilst the remaining fauna assemblage stays the same, with N. pachyderma s.l. (sin) still dominating, reflecting subpolar–polar conditions. Prior to 1.4–1.3 Ma there are very few or no planktonic foraminifers. Low shell fragmentation and lower TOC suggest that the lack of planktonic foraminifers in these sediments cannot be explained either by a shoaling of the carbonate compensation depth or by enhanced supralysoclinal dissolution. Instead, we argue that the appearance of abundant foraminifers in the sediment reflects the same evolutionary adaption of N. pachyderma (sin) to cold conditions to have occurred after 1.1–1.0 Ma as in the North Atlantic.

International audience; Eight SSU rDNA genetic types have been described in the planktonic foraminifera Neogloboquadrina pachyderma, but the level of correlation between genetic diversity and morphological variation remains unknown in this morphospecies. In this study, we combine molecular and morphometric analyses of specimens of N. pachyderma sampled during two consecutive years across a latitudinal gradient in the Indian sector of the Southern Ocean. We observe that three genetic types of N. pachyderma inhabit the (sub-)polar waters of the southern Indian Ocean where they have equivalent regional distributions to those previously observed in the South Atlantic. The geographic ranges of these genetic types are largely overlapping. Our morphometric data show that contrary to other planktonic foraminiferal morphospecies, there is no relationship between genetic diversity and morpho- logical di␣erentiation in at least two of the austral representatives of N. pachyderma (Type III and Type IV) despite a high morphological variability and large genetic distance between these types. These genetic types of N. pachyderma in the southern Indian Ocean thus constitute true cryptic species of planktonic foraminifera.

The paper illustrates and describes 15 species of planktonic foraminifera from the St. Erth Beds, Cornwall, S.W. England. The overlap of the stratigraphic ranges of Globorotalia inflata (d’Orbigny), G. praehirsuta Blow, G. tosaensis Takayanagi & Saito, Pulleniatina primalis Banner & Blow, Neogloboquadrina humerosa (Takayanagi & Saito) and dextrally coiled N. pachyderma (Ehrenberg) places the age of the fauna in the Globorotalia inflata Zone, Late Pliocene. The absence of Globorotalia puncticulata (Deshayes), G. truncatulinoides (d’Orbigny) and Neogloboquadrina atlantica (Berggren) confirms this age assignment and with the presence of G. inflata (d’Orbigny), the deposition of St. Erth beds can now be accurately placed at between 2.1 and 1.9 Ma. For this paper, it has been acceped that the Pliocene-Pleistocene boundary is marked by the first evolutionary appearance of G. truncatulinoides at about 1.9 Ma.

Relative abundance variations of planktonic Foraminifera have been studied for the Late Miocene to Early Pliocene time interval of 7.0 to 3.5 Ma from three sites in the North East Atlantic; DSDP607 (41°N), DSDP609 (50°N) and DSDP611 (53°N), Particular attention has been given to the percentage of benthic Foraminifera of total (benthic + planktonic) Foraminifera as an index of dissolution by aggressive bottom waters, and to the percentage of dextral Neogloboquadrina pachyderma of total (dextral + sinistral) N. pachyderma as an index of “Sub-Polar” or warmer waters.Strong dissolution, probably associated with the northward penetration of aggressive Antarctic Bottom Water, is observed at two of the sites up to and during the initiation of the Messinian “Salinity Crisis” in the adjoining Mediterranean Sea at about 5.8 Ma. All three sites exhibit strong cyclic fluctuations of the percentage of dextral N. pachyderma during the Messinian “Salinity Crisis” interval, from approximately 5.8 Ma to 4.8 Ma. These are interpreted as indicating wide-ranging oscillations of a water mass boundary, analogous to the present-day Polar Front, in the North Atlantic during the “Salinity Crisis”. Following the re-filling of the Mediterranean with normal marine waters at about 4.8 Ma, the dextral form of N. pachyderma, which is more characteristic of warmer waters than the sinistral form, becomes the dominant form and shows less quantitative variation at all three sites throughout the Early Pliocene.

Planktonic foraminiferal faunas have been studied from the Pleistocene of ODP Site 1073 (Leg 174A), New Jersey margin, NW Atlantic Ocean and their abundances have been compared in the >63 μm and >150 μm size-fractions from the same samples. Trends in the relative abundance of many species are similar in the two size-fractions, although the general level varies considerably. The mean abundance and ranges of Neogloboquadrina pachyderma (sinistral), N. pachyderma (dextral), Globorotalia inflata and Globigerina bulloides are greater in the >150 μm size-fraction compared with the >63 μm size-fraction. Turborotalita quinqueloba, Globigerinita uvula, G. glutinata, G. clarkei, and juvenile species are more abundant in the >63 μm size-fraction than the >150 μm size-fraction. Peaks (c. 60%) in abundance of G. uvula occur in the >63 μm size-fraction only, although the causes of these patterns are unclear. The data suggest that, in general, consistent palaeoclimatic/palaeoceanographic information is achieved by studying planktonic foraminiferal faunas from either size-fraction. However, because particular smaller species are either under-represented or even absent from the larger (>150 μm) size-fraction, the smaller (>63 μm) size-fraction must be included in studies of planktonic foraminifera. Furthermore, studies that involve planktonic foraminifera in the >63 μm size-fraction could provide different transfer function estimates for sea surface temperatures in areas where workers have only used larger (>125 μm and >150 μm) size-fractions.

Most palaeo-deep-water reconstructions are based on geochemical information stored in the calcareous shells of Cibicidoides species but hardly anything is known about their life cycle, population dynamics or ecology. The number of specimens of a single Cibicidoides species can locally be very limited and species may be lacking completely during certain intervals in the geological past. As a consequence, geochemical analyses are often carried out on lumped Cibicidoides spp. assuming that they share the same epizoic to epifaunal habitat and precipitated their shell in comparable offsets to surrounding bottom water mass properties. However, there is a growing body of evidence that particularly Cibicidoides pachyderma and its morphotypes C. mundulus and C. kullenbergi, may not be reliable bottom water recorders. We have recently developed aquaria that allowed, for the first time, observations of Cibicidoides pachyderma var. C. mundulus under in situ pressure and temperature. Experiments were carried out with and without artificial sediments to simulate soft sediments and rocks, respectively. Seawater was set to pH 8 and pH 7.4 to simulate more or less particulate carbon export or more or less ventilation of bottom water. Our experiments demonstrate that C. mundulus may opt for an epifaunal or an infaunal habitat depending on elapsed time following physical disturbance, pH, current activity, the availability of sediments and growth. The specimen's initial response following transfer from atmospheric pressure into the high-pressure aquaria was to immerse into the sediment or to cover more or less parts of the test with aggregated sediments or algae. However, within 24 h a strong rheotaxis became apparent and most specimens moved to sites of increased current activity under normal pH conditions (pH 8). Only few specimens remained in algae cysts or in the sediment in the pH-8 experiment. On the contrary, all specimens under pH 7.4 agglutinated a firm sediment cyst around their test and remained infaunal throughout the experimental period of three months. Independent of pH, growth was only observed in specimens that lived within an agglutinated cyst or infaunal. A solid thick cyst covered the specimens of the pH 7.4 experiment throughout the experiment and possibly restricted water exchange between the in-cyst water and the surrounding artificial bottom water mass. We suggest that a more fragile and possibly more porous sedimentary envelope may, at least temporally, have covered the infaunal specimens under pH 8 but no evidence for this was found upon termination of the experiment.

This study focused on planktic foraminifera in plankton tows and surface sediments from the western Indian sector of Southern Ocean in order to evaluate the potential foraminiferal secondary calcification and/or dissolution in the sediment. It is found that the symbiotic foraminiferal species are abundant in the subtropical region, whereas non-symbiotic species dominate in the sub-Antarctic and polar frontal regions. The distribution of the symbiotic and non-symbiotic foraminiferal species is controlled by temperature, salinity, light, nutrients and phytoplankton biomass. There is also a lateral southern extent in abundance of planktic foraminifera from surface sediments to plankton tows. The shell weights of the planktic foraminifera N. pachyderma, G. bulloides and G. ruber within the surface sediments are on an average heavier by 27%, 34% and 40% respectively than shells of the same size within the plankton tows, indicative of secondary calcification. The planktic foraminiferal isotopes show the presence of heavier isotopes in the surface sediment foraminifera as compared to plankton tows, thus confirming secondary calcification. Secondary calcification in G. ruber occurs in the euphotic zone, whereas in case of N. pachyderma and G. bulloides it is at deeper depths. We also observed a decrease in the shell spines in surface sediment foraminifera as compared to plankton tows, indicative of the morphological changes that foraminifera underwent during gametogenesis.

Pachydermoperiostosis (PDP) was first described in 1868. Three forms have been identified: complete (clubbing, periostosis, pachyderma, and cutis verticis gyrata), incomplete (without cutis verticis gyrata), and forme fruste (pachyderma with minimal skeletal changes)1. Two genes have been associated, HPGD and SLCO2A1 2. A 27-year-old British Pakistani man presented with clubbing, hyperhidrosis, palmoplantar hyperkeratosis, and painful swollen knees …

International audience; Planktic foraminifers can be sensitive indicators of the changing environment including both the Arctic Ocean and Southern Ocean. Due to variability in their ecology, biology, test characteristics, and fossil preservation in marine sediments, they serve as valuable archives in paleoceanography and climate geochemistry over the geologic time scale. Foraminifers are sensitive to, and can therefore provide proxy data on ambient water temperature, salinity, carbonate chemistry, and trophic conditions through shifts in assemblage (species) composition and the shell chemistry of individual specimens. Production and dissolution of the calcareous shell, as well as growth and remineralization of the cytoplasm, affect the carbonate counter pump and to a lesser extent the soft-tissue pump, at varying regional and temporal scales. Diversity of planktic foraminifers in polar waters is low in comparison to lower latitudes and is limited to three native species: Neogloboquadrina pachyderma, Turborotalita quinqueloba, and Globigerina bulloides, of which N. pachyderma is best adapted to polar conditions in the surface ocean. Neogloboquadrina pachyderma hibernates in brine channels in the lower layers of the Antarctic sea ice, a strategy that is presently undescribed in the Arctic. In open Antarctic and Arctic surface waters T. quinqueloba and G. bulloides increase in abundance at lower polar to subpolar latitudes and Globigerinita uvula, Turborotalita humilis, Globigerinita glutinata, Globorotalia inflata, and Globorotalia crassaformis complement the assemblages. Over the past two to three decades there has been a marked increase in the abundance of Orcadia riedeli and G. uvula in the subpolar and polar Indian Ocean, as well as in the northern North Atlantic. This paper presents a review of the knowledge of polar and subpolar planktic foraminifers. Particular emphasis is placed on the response of foraminifers to modern warming and ocean acidification at high latitudes and the implications for data interpretation in paleoceanography and paleoclimate research.

The paleoceanographic development of the eastern Fram Strait during the transition from the cold Late Glacial and into the warm Early Holocene was elucidated via a multiproxy study of a marine sediment record retrieved at the western Svalbard slope. The multiproxy study includes analyses of planktic foraminiferal fauna, bulk sediment grain size and CaCO3 content in addition to Mg/Ca ratios and stable isotopes (delta C-13 and delta O-18) measured on the planktic foraminifer Neogloboquadrina pachyderma. Furthermore paleosubsurface water temperatures were reconstructed via Mg/Ca ratios (sSST(Mg/Ca)) and transfer functions (sSST(Transfer)) enabling comparison between the two proxies within a single record. The age model was constrained by four accelerator mass spectrometry (AMS) C-14 dates. From 14,000 to 10,300 cal yr B.P. N. pachyderma dominated the planktic fauna and cold polar sea surface conditions existed. The period was characterized by extensive sea ice cover, iceberg transport and low subsea surface temperatures (sSST(Transfer) similar to 2.1 degrees C; sSST(Mg/Ca) similar to 3.5 degrees C) resulting in restricted primary production. Atlantic Water inflow was reduced compared to the present-day and likely existed as a subsurface current. At ca. 10,300 cal yr B.P. Atlantic Water inflow increased and the Arctic Front retreated north-westward resulting in increased primary productivity, higher foraminiferal fluxes and a reduction in sea ice cover and iceberg transport. The fauna rapidly became dominated by the subpolar planktic foraminifer Turborotalita quinqueloba and summer sSST(Transfer) increased by similar to 3.5 degrees C. Concurrently, the sSST(Mg/Ca) recorded by N. pachyderma rose only similar to 0.5 degrees C. From ca. 10,300 to 8600 cal yr B.F. the average sSST(Mg/Ca) and sSST(Transfer) were similar to 4.0 degrees C and similar to 55 degrees C, respectively. The relatively modest change in sSST(Mg/Ca) compared to sSST(Transfer) can probably be tied to a change of the main habitat depth and/or shift in the calcification season for N. pachyderma during this period.

To describe the horizontal and vertical distribution of recent planktic foraminifera in Fram Strait (Arctic), plankton samples were collected in the early summer of 2011 using a MultiNet sampler (>63 µm) at 10 stations along a west–east transect at 78°50′N. Five depth intervals were sampled from the sea surface down to 500 m. Additionally, sediment surface samples from the same locations were analysed. The ratio between absolute abundances of planktic foraminifera in the open ocean, at the ice margin and in the ice-covered ocean was found to be approximately 2:4:1. The assemblage was dominated by the polar Neogloboquadrina pachyderma (sin.) and the subpolar Turborotalita quinqueloba , which accounted for 76 and 15% of all tests in the warm, saline Atlantic waters and 90 and 5% in the cold and fresh Polar waters, respectively. Both species had maximum absolute abundances between 0 and 100 m water depth, however, they apparently lived shallower under the ice cover than under ice-free conditions. This indicates that the depth habitat of planktic foraminifera in the study area is predominantly controlled by food availability and not by temperature. The distribution pattern obtained by plankton tows was clearly reflected on the sediment surface and we conclude that the assemblage on the sediment surface can be used as an indicator for modern planktic foraminiferal fauna. Keywords : Planktic foraminifera; Fram Strait; Arctic Ocean; depth habitat; N. pachyderma (sin.); T. quinqueloba . (Published: 27 May 2014) To access the supplementary material for this article, please see Supplementary files in the column to the right (under Article Tools). Citation: Polar Research 2014, 33 , 22483, http://dx.doi.org/10.3402/polar.v33.22483

80 sediment stations and 4 sediment cores collected in the Sea of Okhotsk were used in this study in order to reveal additional proxy for past climate reconstruction based on planktonic foraminifera. Variation in diversity indices (Simpson, Shannon and equitability indices) along the sea became additional criteria for 5 biogeographical provinces based on planktonic foraminifera. All of them show different structure aspects of the planktonic foraminifera assemblages that is very informative in cases of high relative abundance of N. pachyderma sin. and influence of carbonate dissolution factor. During the last 100 ky the diversity indices were changed and we can assume the migration of biogeographical provinces borders: borders of the Northern province were mov- ed to the central part in cold MIS 2, 4, structure of assemblages during MIS 3, 5 was close to the modern Central province but characterized by low total foraminiferal abundance in the sediments. The Simpson and Shannon indices are more sensitive to changes in structure of planktonic foraminifera assemblages when equitability index varies lightly during the Late Pleistocene-Holocene.

The timing of vertical migration in planktonic foraminifera (ex. ontogenetic, diel) is still an open debate. This work aims to investigate the diel vertical migration (DVM) of Neogloboquadrina pachyderma (N. pachyderma) and Turborotalitaquinqueloba (T. quinqueloba) in the Arctic during the midnight sun. N. pachyderma and T. quinqueloba dominate the total assemblage in the cold Polar Water and warmer North Atlantic Water masses, respectively. Foraminifera were collected at several depths along the Fram Strait. Afterwards sampling was performed at the same station for 24 h at continuous and discrete time intervals. Results show no evidence of planktonic foraminifera DVM since there was no significant variability in the abundance and size distribution during the 24-h collection period. This finding provides information to improve the interpretation of foraminifera in paleoclimatic works. This is especially relevant in the Fram Strait as paleoclimatic studies in this region are fundamental to investigating the history of the Atlantic water inflow into the Arctic Ocean.

Touraine Solente Gole syndrome is a rare hereditary syndrome of primary pachydermoperiostosis, with the characteristic triad of pachydermia (or elephant like skin), periostosis and acropachia. A 27-year-old patient presented with aesthetic deformity of forehead due to deep skin folds and coarsening of facial features due to progressive thickening of skin. Associated palmoplantar hyperkeratosis with broadened of finger and toe tips and digital clubbing were noticed. Dermatologic evaluation revealed cutis verticis gyrata of scalp, seborrhoeic hyperplasia of face and hyperhidrosis. Natural history of the disease and aetiopathogenesis were reviewed. Aesthetic correction of forehead through frontal rhytidectomy was attempted.

The North Atlantic and Norwegian Sea are prominent sinks of atmospheric CO_2 today, but their roles in the past remain poorly constrained. In this study, we attempt to use B/Ca and δ^(11)B ratios in the planktonic foraminifera Neogloboquadrina pachyderma (sinistral variety) to reconstruct subsurface water pH and pCO_2 changes in the polar North Atlantic during the last deglaciation. Comparison of core-top results with nearby hydrographic data shows that B/Ca in N. pachyderma (s) is mainly controlled by seawater B(OH)_4−/HCO_3− with a roughly constant partition coefficient (K_D = [B/Ca]_(CaCO_3) / [B(OH)_4−/HCO_3− (seawater)) of 1.48 ± 0.15 × 10^(−3) (2σ), and δ^(11)B in this species is offset below δ^(11)B of the borate in seawater by 3.38 ± 0.71‰ (2σ). These values represent our best estimates with the sparse available hydrographic data close to our core-tops. More culturing and sediment trap work is needed to improve our understanding of boron incorporation into N. pachyderma (s). Application of a constant K_D of 1.48 × 10^(−3) to high resolution N. pachyderma (s) B/Ca records from two adjacent cores off Iceland shows that subsurface pCO_2 at the habitat depth of N. pachyderma (s) (~50 m) generally followed the atmospheric CO_2 trend but with negative offsets of ~10–50 ppmv during 19–10 ka. These B/Ca-based reconstructions are supported by independent estimates from low-resolution δ^(11)B measurements in the same cores. We also calibrate and apply Cd/Ca in N. pachyderma (s) to reconstruct nutrient levels for the same down cores. Like today's North Atlantic, past subsurface pCO_2 variability off Iceland was significantly correlated with nutrient changes that might be linked to surface nutrient utilization and mixing within the upper water column. Because surface pCO_2 (at 0 m water depth) is always lower than at deeper depths and if the application of a constant KD is valid, our results suggest that the polar North Atlantic has remained a CO_2 sink during the calcification seasons of N. pachyderma (s) over the last deglaciation.

The oxygen isotopic composition (delta O-18) of planktonic foraminiferal shells in seafloor sediment provides information on past surface oceanography. Knowledge of seasonal and depth habitat, as well as the delta O-18 disequilibrium (vital effect), is essential to constrain the interpretation of sedimentary delta O-18. Here, we present a 1-year time series of planktonic foraminiferal shell fluxes and delta(18)Ofrom a sediment trap moored in the northwestern margin of the North Pacific. The vital effect and calcification depth for four species were estimated by comparing shell delta O-18 and the predicted values of equilibrium calcite calculated from temperature and estimated delta O-18 in seawater. Six major species (Neogloboquadrina incompta, Nedgloboquadrina dutertrei, Neogloboquadrina pachyderma, Globigerina quinqueloba, Globigerina bulloides, and Globorotalia scitula) constituted 97% of the total foraminiferal flux. Most major species showed large fluxes in June and December, corresponding to periods of the development and disruption of the seasonal thermocline, implying the importance of nutrient injection and/or circulation for foraminiferal fluxes. Additional peaks in N. dutertrei and N. pachyderma were observed in August. The seasonal successions of foraminiferal fluxes corresponded to surface ocean stratification conditions and food availability, which are closely related to circulation of local currents. Vital effect estimations suggest that shells calcified in equilibrium for G. bulloides and N. pachyderma [sinistral (s)1 and with a -0.7% offset for N. dutertrei [dextral (d)], a -1.0%, offset for N. incompta (d), and a -03% offset for N. pachyderma (d). The calculation of flux-weighted delta O-18 values reveals that the sedimentary delta O-18 values of G. bulloides, N. dutertrei (d), and N. incompta (d) reflect surface temperature in winter season, and those of N. pachyderma (s) and N. pachyderma (d) reflect summer and annual mean subsurface temperature, respectively. The shallow calcification depths for the four species suggest that delta O-18 between different species (Delta delta O-18) in the western North Pacific does not work for reconstructing past stratification conditions, unlike in other regions. Rather, the delta O-18 between N. pachyderma (s) and G. bulloides, N. dutertrei (d) or N. incompta (d) may be a more suitable proxy for past seasonality. (C) 2013 Elsevier B.V. All rights reserved.

Earlier reconstructions of the inflow of Atlantic Water to Arctic and Subarctic oceans based on foraminiferal proxy data have been obstructed by uncertain quantitative reconstructions of sea-surface and subsurface temperatures. In this study surface sediment samples with undisturbed sediment-water interface from Polar North Atlantic and Barents Sea were retrieved and prepared at the size fractions from 100 μm to 1000 μm. The foraminiferal analyses show that Neogloboquadrina pachyderma constitutes 96–99% of the fauna in Arctic and Polar surface water masses the same result is obtained when investigating the > 150 μm size fraction. However, in Arctic areas influenced by Atlantic Water, additional faunal information is obtained when using the smaller > 100 μm size fraction. In these areas, N. pachyderma is reduced to about 50%, and the relatively small species Turborotalita quinqueloba becomes very frequent. This also applies to the Coastal Water masses, which are dominated by Neogloboquadrina incompta and Globigerinita uvula. Transfer functions using the current dataset based on the > 100 μm size fraction were developed and assessed. Different statistical models were tested, using both seasonal and annual temperature data from 0 m, 10 m, 50 m, and 100 m water depth. The most precise reconstructions of subsurface temperatures were found when using summer temperatures from the 100 m depth level. The transfer function was tested on Holocene foraminiferal records and compared to previous reconstructions. The results show that our new transfer function based on the > 100 μm fraction generally yields lower temperatures at both 10 and 100 m water depth than earlier reconstructions (e.g. Hald et al., 2007). This could be due to the increased number of samples containing both small species and/or the presence of more small specimens representing cold conditions.

[1] Past water column stratification can be assessed through comparison of theδ18O of different planktonic foraminiferal species. The underlying assumption is that different species form their shellssimultaneously, but at different depths in the water column. We evaluate thisassumption using a sediment trap time-series of Neogloboquadrinapachyderma(s) and Globigerina bulloides from the NWNorth Atlantic. We determined fluxes, δ18O and δ13C of shells from two size fractionsto assess size-related effects on shell chemistry and to better constrain the underlying causes of isotopic differences between foraminifera in deep-sea sediments. Our data indicate that in the subpolar North Atlantic differences in the seasonality of the shell flux, and not in depth habitat or test size, determine the interspecies Δδ18O. N. pachyderma(s) preferentially forms from early spring to late summer, whereas the flux ofG. bulloides peaks later in the season and is sustained until autumn.Likewise, seasonality influences large and small specimens differently, with large shells settling earlier in the season. [2] The similarity of the seasonal δ18O patterns between the two species indicatesthat theycalcify in an overlapping depth zone close to the surface. However, their δ13C patterns are markedly different (>1 ‰). Bothspecies have a seasonally variable offset from δ13CDIC that appears to be governed primarily by temperature, with larger offsets associated with higher temperatures. The variable offset from δ13CDIC implies that seasonality of the flux affects the fossil δ13C signal, which has implications for reconstruction of the past oceanic carbon cycle.