Recent Foraminifera Research Articles

Transfer of the Brent Wilson microfossil collection to the European Micropalaeontological Reference Centre

The Wilson collection at the EMRC holds a total of 300 microscope slides and consists mostly of picked and sorted assemblages of Miocene and Recent foraminifera from Trinidad and Tobago. The collection includes the holotype and paratypes of the species Asterigerina murraynhaynesi Wilson and Hayek.

Recent Foraminifera From the Mahanadi River Estuary, East Coast of India

The Mahanadi River estuary (Figure 1) is one of the major estuaries in India and the largest one in the Odisha State. It is situated within latitudes 190 47? and 200 30? N and longitudes 850 33? and 860 49? E. It originates from Amarakantak region of Madhya Pradesh and flows through Madhya Pradesh and Odisha States over a length of 890 kms having a drainage basin of about 1,41,600 sq. kms with a large catchment area. It opens into the Bay of Bengal at Pardeep in Cuttack district. It has a wide opening into the sea at its northeastern end. The tidal stretch extends up to 32 kms from the mouth. The entire area is full of mangrove vegetation together with mud flats traversed by a network of tidal creeks except some portions such as Paradeep and Astaranga mouth regions which are sandy shorelines. The studies on Recent foraminifera in relation to the prevailing ecological parameters such as salinity, temperature, dissolved oxygen, and pH, and sediment characteristics and organic matter content of the sediments have been carried out in the present investigations. These studies can be used to delineate the palaeo-environments which serve as useful tools in the exploration for petroleum. 10 sediment and 10 water samples were collected from the estuary for the study of foraminifera and sediment characters, and water analysis respectively. The foraminifera of the estuary were identified. 12 abundant species which are Ammobaculities exiguus, Ammonia beccarii, Ammonia beccarii tepida, Elphidium advenum, Elphidium hispidulum, Milliamina fusca, Nonion depressulus, Pararotalia nipponica, Pararotalia cf. globosa, Quinqueloquelina lamarckina, Quinqueloculina seminulum and Rosalina globularis and are related to the prevailing ecological parameters and the substrate characteristics including the organic matter content.

Recent Foraminifera from the coast of Mumbai, India: distribution and ecology

Foraminifera have been used in biostratigraphy and paleoenvironmental research. They are useful environmental indicators for monitoring the marine environment. Intertidal sediment samples were analysed for their diversity in relation to physicochemical parameters and sediment characteristics along the Mumbai coast of India. Thirty-five species were found, divided into five orders and 18 families. The orders Rotaliida and Miliolida were identified to be dominant. Foraminifera were observed to be inversely related to sand particle size in relation to sediment and physicochemical parameters of water. Canonical correlation analysis explained the relationship between species abundance and water physicochemical parameters.

The response of benthic foraminifera to environmental changes in Epie creek, Yenagoa, Bayelsa State

Epie creek, located at the Southern part of Nigeria has been known for its use as sink for the disposal of untreated sewage and industrial effluents. Benthic foraminifera are increasingly been used as environmental bio-indicators of pollution. Their munity structure provides information on the general characteristics of the environment and some species are sensitive to specific environmental parameters. This study investigates recent foraminifera from sediment samples collected from ten (10) stations (ranging in depths from 1m to 4.2m) in the Epie creek from Igbogene to Tombia- Etegwe. The environmental factors that necessitate their existence such as temperature, pH, salinity and dissolved oxygen were measured during the sampling time. Metals were determined using atomic absorption spectrophotometer. Recognized benthic foraminifera species belonging to four (4) genera of three (3) families and four(4) suborder were identified. Five (5) benthic foraminifera taxa were identified from sediment samples which include Lenticulina stellata, Saccammina sp, Marginulina costata, Marginulina cf. planata and Trochammina sp. The stress tolerant specie, Trochammina ,sp. was common in the study area confirming a stressed environment.

Contrasting vertical distributions of recent planktic foraminifera off Indonesia during the southeast monsoon: implications for paleoceanographic reconstructions

Abstract. Planktic foraminifera are widely used in paleoceanographic and paleoclimatic studies. The accuracy of such reconstructions depends on our understanding of the organisms' ecology. Here we report on field observations of planktic foraminiferal abundances (>150 µm) from five depth intervals between 0–500 m water depth at 37 sites in the eastern tropical Indian Ocean. The total planktic foraminiferal assemblage here comprises 29 morphospecies, with 11 morphospecies accounting for 90 % of the total assemblage. Both species composition and dominance in the net samples are broadly consistent with the published data from the corresponding surface sediments. The abundance and vertical distribution of planktic foraminifera are low offshore western Sumatra and increase towards offshore southern Java and the Lesser Sunda Islands (LSI). Average living depth of Trilobatus trilobus, Globigerinoides ruber, and Globigerina bulloides increases eastward, while that of Neogloboquadrina dutertrei, Pulleniatina obliquiloculata, and Globorotalia menardii remains constant. We interpret the overall zonal and vertical distribution patterns in planktic foraminiferal abundances as a response to the contrasting upper-water-column conditions during the southeast monsoon, i.e., oligotrophic and stratified offshore Sumatra (non-upwelling) vs. eutrophic and well mixed offshore Java–LSI (upwelling). Overall, the inferred habitat depths of selected planktic foraminifera species show a good agreement with those from sediment trap samples and from surface sediments off Sumatra, but not with those from surface sediments off Java–LSI. The discrepancy might stem from the different temporal coverage of these sample types. Our findings highlight the need to consider how foraminiferal assemblages and ecology vary on shorter timescales, i.e., from “snapshots” of the water column captured by a plankton net to seasonal and interannual variability as recorded in sediment traps, and how these changes are transferred and preserved in deep-sea sediments.

Distribution Patterns of Inner Shelf Benthic Foraminifera and Their Relationship to Climatic Conditions in Northeastern Tamil Nadu, India

The present study, involving investigations of recent foraminifera from the sediments of the inner shelf off Nagapattinam on the southeast coast of India, was undertaken to document the composition, distribution, and ecology of the foraminifera and their relationship to the climatic conditions of the study area. Thirty sediment samples were collected from depths ranging from 3.4 to 30.8 m during the fieldwork conducted in July 2001 and various ecological parameters were determined. Sediment samples from the sediment-water interface yielded 151 benthic foraminifera species and varieties belonging to 82 genera, 42 families, 21 superfamilies, and 5 suborders, which have been described and illustrated in this study. The spatial and temporal variations of total (“live” + dead) foraminifera populations were analysed. The study shows significant total populations in the collected samples. This was attributed to higher temperatures resulting in higher salinities during this period. Both species and genus diversity increase with increasing depth. In the context of the Indian Ocean tsunami, the pronounced changes in the nearshore continental region will certainly provide a different picture, and the present results would provide a reliable database for comparative post-tsunami studies. The results show a clear relationship between foraminifera and local climatic conditions.

Predatory Drilling Traces on Recent Foraminifera from Chandipur Coast, India

Predatory Drilling Traces on Recent Foraminifera from Chandipur Coast, India

Distribution of recent Foraminifera as depositional indicators in Yongle Atoll, Xisha Islands, South China Sea

Abstract The key to the utility of foraminifers as paleo-environmental indicators for coral reefs is the knowledge of modern assemblages in relation to environmental conditions. This study examined 44 surface-sediment samples from three small islands in Yongle Atoll, with the goal to investigate the relationship between foraminiferal distribution and environmental characterization. In samples, 192 foraminiferal species belonging to 74 genera were identified, among which the hyaline foraminifers totally dominated. Hierarchical Cluster Analysis resulted in the identification of three foraminiferal biofacies, representing different environmental settings and sedimentary regimes. (1) The Amphistegina (mainly Amphistegina lobifera) facies characterizes the upper fore-reef slope zone, which experiences strong wave action and currents from the open sea. (2) The Calcarina hispida–Neorotalia calcar facies represents the reef flat and lagoon slope zone, and patch reefs in the lagoon basin, which is the shallowest of all the biofacies, exposed to the strong solar radiation and strong hydrodynamic activity. (3) The Quinqueloculina crassa subcuneata–Elphidium advenum facies characterizes the lagoon basin, which is covered by fine sands and muds with abundant Halimeda fragments to water depths

Richness in recent foraminifera from different locations along Venezuelan coastal ecosystems

The total number of recent foraminifera species for Venezuelan marine areas is counted and summarized by major taxonomic groups. Samples from different locations associated with contrasting marine settings were used to review the species richness of the foraminiferal community. Atotal of 930 species were compiled and their synonyms updated. Of this total, 392 species belong to the Rotaliida (42%), 234 to theMiliolida (25%), 155 to the Textulairida (17%), and 79 species to the Lagenida (8%), while the Nodosairida has 18 species (2%), the Spirilinida has 17 (2%), the Polymorphinida has 14 (2%), and the rest belong to the Vaginulinida, Robertinida, Carterinida and Involutinida (12, 6, 2 and 1 species each, respectively). Atotal of 271 species have been identified as endemic to theVenezuelan marine coastal area. This basic diversity analysis of species indicates that the Rotaliida dominate the foraminiferal assemblages along the coast line, followed by the Miliolida and Textulariida, with minor representation of other groups of foraminifera. The distribution of the foraminiferal species, especially benthic, is associated with the different ecoregions and can help serve as indicators for environmental health, marine restoration, and preservation of environmental quality.

Sampling strategy always matters: Methodological issues on collecting samples in tropical transitional environments for ecological analysis based on recent foraminifera

Sampling strategies and methodological procedures are a theme of discussion in all areas of Science, considering their potential impacts on results, interpretations, and conclusions. In the case of ecological studies based on recent foraminifera, most of papers vary on collecting single samples or replicates, on counting living and/or dead assemblages, and on the depth of the sediment layer collected. In this study we discussed the implications of the following questions, especially in the intertidal zone of a tropical estuary: (i) Do collecting a single sample or replicates affect results and interpretations? (ii) Are there differences in results and interpretations generated from counting living (stained) or dead assemblages?; and (iii) Do varying the sampling depth of sediment layers influence the results and interpretations? We defined three collection points along the mangrove margins associated to the Itapanhaú River (Bertioga, State of São Paulo, Brazil). In each point, we drilled three microcores with the depth of 20 cm, laterally distant 30 cm from each other. In each microcore sediment samples (3 mL) were extracted in the layer intervals of 0–1, 4–5, 9–10, 14–15, and 19–20 cm. Foraminifera from all the samples were compared regarding absolute abundances, species composition, diversity, evenness and, communities similarities. We observed that replicates produce better results than single samples, both for the living and dead assemblages. Pseudoreplication simulation produced divergent results. Replicates make possible the application of more accurate inferential statistical analysis because the spatial variations of the species are captured. There were significant differences in ecological indicators and respective interpretations between analyzes based on counting living and dead assemblages so that they should not be considered directly comparable to each other. Counting living foraminifera requires higher effort for collecting and picking tests to reach the statistical minimum recommended. Regarding sampling depth, the first centimeter seems to be sufficient to find the vast majority of living foraminifera, mainly to estimate species richness. However, thicker sediments result in a longer time interval integrated into the sample, so the time-scale and variables that control foraminifera may change for interpretation. Our findings are consistent with previous studies carried out in subtropical estuaries, also expanding methodological recommendations to tropical estuaries. Future studies should explore the best distances among replicates.

Taxonomic notes on Recent Foraminifera from the Continental Shelf-Slope Region of Southwestern Bay of Bengal, East Coast of India

Taxonomic notes on Recent Foraminifera from the Continental Shelf-Slope Region of Southwestern Bay of Bengal, East Coast of India

Two New Species of Recent and Upper Holocene Coccolith-agglutinated Foraminifera from the North Icelandic Shelf, North Atlantic

AbstractTwo new coccolith-agglutinated foraminiferal species, Pseudobolivina islandica n. sp. and Haplophragmoides atlanticus n. sp., are described from Recent and Upper Holocene sediments at Húnaflóaáll on the North Icelandic shelf. Specimens of the two species have been found only in the small (63–106 µm) fraction using the wet-counting method. This method allows preservation of these fragile tests, which are predominantly composed of coccoliths, mainly of the species Coccolithus pelagicus (Wallich, 1877).

Foraminiferal assemblages along the intertidal zone of Itapanhaú River, Bertioga (Brazil)

Foraminifera found in intertidal zones have been successfully used in studies examining relative sea level monitoring around the world. For this purpose, it is necessary to establish the typical foraminiferal assemblages of different salinity regimes and sediment sub aerial exposition. In the present work we collected 27 sediment samples from 5 transversal transects in the mangroves of the Itapanhaú River (Bertioga, SP, Brazil). Transects were distributed along salinity and altitudinal gradients in order to study the community structure of recent foraminifera in terms of diversity and species composition. We identified 35 species and described 5 groups of species in different environmental settings, from downstream to upstream and from margin to landward in the mangrove forest, associated with salinity regime and sediment proportional exposure time. These variables seem to primarily control species distribution and community structure in the intertidal zone, although dissolution of calcareous taxa cannot be ruled out. The first group is dominated by Ammonia spp. and Elphidium spp., colonizes the mouth of the river on an unvegetated tidal flat in the lowest portion of the intertidal zone, under a polyhaline regime. This group exhibits the smallest sub aerial exposition (19,3%) as well as comparatively high species diversity. The second group is formed by a sample dominated by Trochammina inflata and Arenoparrella mexicana, obtained in a polyhaline area on the margin of the mangrove. The third group is dominated by Miliammina fusca and Ammotium spp., and colonizes mesohaline mangrove forests, with proportional exposure time of between 50 and 75%, and high species diversity. The fourth group comprises communities dominated by M. fusca and T. inflata, and colonizes the intermediate level in the interior of the mangrove forest, exhibiting high species diversity. The fifth group comprises communities broadly dominated by M. fusca, colonizing oligohaline margins and the highest level of polyhaline mangrove forests. This group exhibits the greatest sub aerial exposition and lowest species diversity of all five groups. Hence, these foraminifera groups may serve as a reference with which to interpret drilling core layers and reconstruct relative sea levels in other similar estuarine systems.

Foraminiferal research in coastal ecosystems of India during the past decade: A review

Coastal habitats in India, including estuaries, creeks and bays, have degraded to varying degrees, depending on the fluxes of pollutants and flushing characteristics of the area. Bioindicators can provide consistent evidence for degradation or recovery and have proven particularly useful in monitoring and assessment of coastal ecosystems. This paper examines and reviews recent research on modern foraminifers in coastal ecosystems of India. Most of the studies discuss methodologies employed with respect to sampling devices, sample storage, treatment, faunal analysis and documentation. A major goal of this review is to highlight the results of investigations on recent foraminifera carried out to date, and to identify minimally studied topics and geographic regions to thereby recommend areas for future study of coastal environments of the Indian Subcontinent.

Marine ecology conditions at Weda Bay, North Maluku based on statistical analysis on distribution of recent foraminifera

Analysis of foraminifera in geology,usually being used to find the age of rocks/ sediments and depositional environment. In this study, recent foraminifera was used not only to determinethe sedimentary environment,but also to estimate the ecological condition of the water through a statistical approach.Analysis was performed quantitatively in 10 surface seabed sediment samples in Weda Bay North Maluku. The analysis includes dominance (Sympson Index), diversity and evenness (Shannon Index), and the ratio of planktonic -benthic. The results were shown in the plotting diagram of M-R-T (Miliolid-Rotalid-Textularid) to determine the depositional environment. Quantitative analysis was performed using Past software (paleontological version Statistic 1:29).The analysis result showed there was no domination of certain taxon with a moderate degree of evenness and stable communities and considerably a moderate diversity. The results of this analysis indicated that research area had a stable water conditions with the optimum level of carbonate content, oxygen supply, salinity, and temperature. The ratio of planktonic and benthic indicate the relative depth, which was deeper the water increased the percentage of planktonic foraminifera. Based on M-R-T diagram showed the distribution of sediment deposited on exposed carbonate (carbonate platform) environment with normal saline.

The foraminifera.eu database: concept and status

The foraminifera.eu project with its 120 avocational and professional scientific contributors has built a popular online image database containing information about fossil and recent foraminifera. Foraminiferal data available from over 200 years of scientific studies and publications were first analyzed in order to create a robust database using structurable and available data-attributes. A freely accessible database with online interfaces was established to improve the accessibility of foraminiferal data. So far, the database contains 9,800+ records of specimens with images and accompanying metadata. Thirty data attributes were chosen, and discrete values were defined and applied to each dataset covering the areas of identification, geographical and stratigraphical positioning, morphology, synonyms, references, and collection related data. The attributes were chosen based on their usefulness to both avocational and professional scientists and on their general availability. A discussion and review process has been established to enlarge the database by adding more records and to implement new data attributes and interfaces. In 2015, the database was accessed on average by 220 users daily (excluding bots) and 0,8 gigabytes of data were downloaded each day. The numbers indicate the utility and relevance of the foraminifera.eu database, and this is also acknowledged by senior scientists and major institutions through their contributions.

2014 JOSEPH A. CUSHMAN AWARD TO STEPHEN J. CULVER

Stephen J. Culver is the 2014 recipient of the prestigious Joseph A. Cushman Award for Outstanding Achievement in Foraminiferal Research. Stephen is the quintessential foraminiferalogist. His contributions range temporally from Early Cambrian to Recent, environmentally from the intertidal to the abyss and geographically from the Atlantic Coastal Plain of the United States to Malaysia. His contributions (over 150 publications) range from detailed studies on very specific topics to broad insightful reviews to the geology of entire countries (Sierra Le-one). Steve has accumulated knowledge first hand from extensive field work ranging from the Outer Banks of North Carolina to Africa, as well as in the deep-diving submersible, Alvin . The prerequisites for becoming a successful geologist/paleontologist appeared early on when he was a boy. He loved collecting and learning about fossils and was fascinated by maps. After earning his Ph.D. in 1976 at the age of 24 from the University of Wales at Swansea, U.K., he taught for two years at the University of Sierra Leone. As a post-doctoral fellow at the Smithsonian Institution from 1978–81, Stephen undertook and completed one of the most ambitious foraminiferal projects ever attempted. Using all the data (691 papers from 1839–1979) ever published, catalogs on the distribution of Recent foraminifera on the continental margins of North America were compiled on a primitive mainframe computer. The data were transmitted from the Cushman Collection, Todd Library, and card catalogs over a phone line using a teletype machine. At one point, after months of data entry, the entire file went missing. After a few hours of utter anguish, Culver was relieved to find out that the file had …

Distribution and morphological abnormalities of recent foraminifera in the Marano and Grado Lagoon (North Adriatic Sea, Italy)

The Marano and Grado Lagoon, is a northern Adriatic wetland system of relevant naturalistic and economic value, that is constantly under quality control in accordance with the current environmental directives. Benthic foraminifers community with its morphological abnormalities were investigated in the recent sediments (about 10 years old) of 21 stations collected in the framework of the “MIRACLE” Project which aimed at testing the coexistence of clam farming with high Hg contamination. Euryhaline foraminifers, well known in Mediterranean brackish-waters, mainly characterizes the total assemblage. A. tepida dominates in areas characterized by low salinity, high clay and Corg content, but also to anthropogenic pressure. E. gunteri and H. germanica are recorded in the western sector of the lagoon, which is more affected by salinity variations and agricultural activities. Slightly higher values of assemblage diversity appear in less restricted areas of the lagoon or, at least, where physical parameters such as temperature and salinity are less variable. The test abnormalities, carried out on total assemblage, shows that the FAI (Foraminiferal Abnormality Index) values always exceed 1% of the total assemblage, with clear decreasing gradients from inland to the sea (from N to S) and from W to E in the studied area.

Cenomanian‐Coniacian Sea‐level Change and Dissolved Oxygen Fluctuations in Tethys‐Himalaya: Evidences from Benthic Foraminifera of Gamba, Tibet

Abstract:Benthic foraminifera, preserved in the Late Cretaceous organic carbon‐rich sediments of Gamba, southern Tibet, provide high‐resolution proxies for sea‐level changes and dissolved oxygen fluctuations of southeastern Tethys. The fossils were statistically analyzed and divided into three faunas of “Cenomanian fauna”, “Turonian fauna”, and “Coniacian fauna”. A middle neritic‐upper bathal environment (50–250m) was estimated considering the ratios of planktonic and epifaunal benthic foraminifera (P/(P+E)), the morphological analysis according to the studies of recent foraminifera and the abundant distributions of depth‐related species such as Alabamina creta, Laevidentalina sp., Praebulimina spp., Pleurostomella cf. naranjoensis, Pyrulina sp., Quinqueloculina spp., Haplophragmoides spp., etc. The result shows an almost parallel trend with the global transgressive and regressive cycles, but the former fluctuates more frequently at upper Cenomanian, which probably indicates tectonic instability of the continental margin. According to the benthic foraminiferal richness (BFN), Shannon‐Weiner diversity (H(s)), as well as benthic foraminiferal oxygen index (BFOI), five periods of oxygen depleted conditions (dysoxic‐anoxic) have been recognized. They correspond to the OAE2, the lower Turonian, the upper Turonian, the Turonian‐Caniacian boundary event and the probably OAE3. In addition, the oxygen fluctuations in Gamba might be controlled directly by sea‐level changes, while the paleoproductivity and oxygen conditions interacted with each other under oxygen deficiency environments.

Sedimentary and foraminiferal evidence of the 2011 Tōhoku-oki tsunami on the Sendai coastal plain, Japan

The 2011 Tōhoku-oki megathrust earthquake (Mw 9.0) generated a tsunami that reached the Sendai coastal plain with flow heights of ~2 to 11m above TP (Tokyo Peil). We examined the tsunami deposit exposed in 14 shallow trenches along a ~4.5‐km transect perpendicular to the coast. We primarily document the stratigraphical, sedimentological, foraminiferal and geochemical characteristics of the Tōhoku-oki tsunami deposit and perform a preliminary comparison with sediments deposited by the Jōgan tsunami of A.D. 869.In the coastal forest and rice fields inundated by the Tōhoku-oki tsunami, a poorly sorted, dark brown soil is buried by a poorly sorted, brown, medium-grained sand deposit. In some trenches located more than 1.2km inland, the sand is capped by a thin muddy-sand layer. The tsunami deposit, although highly variable in thickness, is generally thickest (25cm) near the coastal dune and thins to less than 5mm at ~4.5km inland. The tsunami deposit was discriminated from the underlying soil by the appearance of recent and fossil foraminifera and a pronounced increase in grain size that fined upward and landward. The recent foraminifera preserved in the sandy facies of the deposit are rare and showed evidence of prolonged subaerial exposure (e.g. pitting, corrosion, fragmentation). Recent foraminifera likely originated from coastal dune and beach sediments that were breached by the tsunami. Calcified and sediment in-filled, fossil foraminifera are abundant and were eroded from sedimentary units and transported by fluvial or wave activity to Sendai Bay. Trends associated with test size (e.g. decreasing concentration of large test sizes with distance inland) are in agreement with grain size data. At two locations a decrease in total organic carbon and an increase in δ13C were found in the tsunami sand compared with the underlying soil, supporting a beach to intertidal origin for the upper unit.