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At least 19 recordsLinked to original sources
USGS2019

Microbial associations of four species of algal symbiont-bearing Foraminifers from the Florida Reef Tract, USA

While microbiome research is a rapidly expanding field of study, relatively little is known of the microbiomes associated with Foraminifera. This preliminary study investigated microbes associated with four species of Foraminifera, representing two taxonomic orders, which host three kinds of algal endosymbionts. A major objective was to explore potential influences on the microbiome composition, including phylogenetic relatedness among the host species, similarities in algal symbionts hosted, and environmental conditions from which the specimens were collected. Samples examined from two locations along the middle Florida Keys reef tract included 45 foraminiferal specimens and four environmental samples. Bacterial DNA extraction from individual specimens was followed by amplification and amplicon sequencing of the V4 variable region of the 16S rRNA gene; results were obtained from 21 specimens. The Order Miliolida, Family Soritidae, was represented by 5–8 specimens of each of three species: Archaias angulatus and Cyclorbiculina compressa , which both host chlorophyte symbionts, and Sorites orbiculus , which hosts dinoflagellate symbionts. Three Ar. angulatus specimens from which the microbiome was successfully sequenced shared 177 OTUs. Six C. compressa specimens successfully sequenced shared 58 OTUs, of which 31 were also shared by the three specimens of Ar. angulatus . Four successfully sequenced S. orbiculus specimens shared 717 unique OTUs. The 13 soritid specimens shared 26 OTUs, 23 of which represented Proteobacteria, predominantly of the bacterial family Rhodobacteraceae. The fourth foraminiferal species, Amphistegina gibbosa (Order Rotaliida) hosts diatom endosymbionts. Bacterial DNA extraction was attempted on 16 Am. gibbosa , including both normal-appearing and partly-bleached specimens. Only six OTUs, four of which represented Proteobacteria, were found in all eight specimens successfully sequenced. The partly bleached specimens shared nearly twice as many unique microbial OTUs (32) as the normal-appearing specimens (19). All Am. gibbosa specimens shared only four microbial OTUs with the soritid species, three of which may have been contaminants, indicating minimal commonality between the microbiomes of Am. gibbosa and the soritid taxa.

Florida↗
USGS2003

Late cretaceous foraminifera, paleoenvironments, and paleoceanography of the rosario formation, San Antonio del Mar, Baja California, Mexico

The 315 m of Rosario Formation exposed at the San Antonio del Mar (SADM) section (Baja California, Mexico) contains moderately-to-well preserved benthic and planktic foraminifera, calcareous nannofossils, and molluscs. Nannofossils suggest most of the SADM section was deposited within a narrow interval of the late Campanian (CC21-CC22), whereas foraminifera and molluscs suggest a younger maximum age (younger than the Globotruncana ventricosa Zone) and allow deposition over a longer interval of time. Planktic foraminifera at SADM represent common Tethyan taxa. They are largely restricted to the lower and middle portions of the section and comprise 0-???40% of foraminiferal assemblages. Stable isotopic analyses of Rugoglobigerina rugosa yield ??18OV-PDB values from -2.27%, to -2.82%, corresponding to salinity-corrected paleotemperature estimates of 26-30??C for the Late Cretaceous eastern Pacific. These estimates are as warm as modern tropical temperatures and are similar to tropical paleotemperature estimates from ??18O analyses of exceptionally preserved Maastrichtian samples; however, they are considerably warmer than most tropical Campanian-Maastrichtian estimates. Benthic foraminifera indicate outer shelf paleodepths with a slight increase in depth or decrease in benthic oxygen levels in the upper parts of the interval studied. The change in the benthic assemblage corresponds to an ???1??? positive shift in benthic ??O18, suggesting a relationship between benthic assemblages and an inferred increase in the local intensity of upwelling.

Journal of Foraminiferal Research↗
USGS2006

Distribution of foraminifera in Pamlico Sound, North Carolina, over the past century

Foraminiferal and radionuclide data have been used to investigate environmental change that has occurred within Pamlico Sound, North Carolina, over the last century. Environmental conditions were evaluated for three time slices; (1) the modern environment as determined by surficial (0-1 cm) sediments, (2) short-core intervals representing approximately 40 years BP, as determined by 137Cs activity, and (3) short-core intervals representing approximately 120 years BP, as determined by 210Pb activity. Cluster analysis distinguished four foraminiferal assemblages at the surface (0-1 cm): (1) Marsh Biofacies, (2) Estuarine Biofacies A, (3) Estuarine Biofacies B, and (4) Marine Biofacies. The Marsh Biofacies is characterized by typical marsh foraminifera such as Tiphotrocha comprimata, Trochammina inflata, Miliammina fusca and Haplophragmoides wilberti. Estuarine Biofacies A is distinguished from Estuarine Biofacies B by the greater relative abundance of the agglutinated species Ammotium salsum and Ammobaculites crassus in the former and the greater relative abundance of Elphidium excavatum in the latter. The Marine Biofacies is comprised completely of calcareous foraminifera (e.g., Elphidium excavatum, Hanzawaia strattoni, Cibicides lobatulus, Elphidium subarcticum, Quinqueloculina seminula and Elphidium galvestonense) and is restricted to tidal inlets. Down-core foraminiferal data indicate that approximately 120 years BP, Pamlico Sound was dominated by Estuarine Biofacies A, which is indicative of brackish conditions. Upcore in the 40 years BP and modern time slices, Estuarine Biofacies B is the more prominent assemblage within Pamlico Sound; this is indicative of increased salinity over time. Lowered salinity conditions 120 years BP may be the result of high hurricane activity over a several year period.

Journal of Foraminiferal Research↗
USGS1982

Biostratigraphy and paleoenvironment of Miocene- Pliocene hemipelagic limestone: Kingshill Seaway, St. Croix, US Virgin Islands.

The Kingshill Limestone and younger carbonate rocks constitute the central portion of St. Croix, forming the remains of an ancient seaway that was flanked by emergent highlands. The seaway has been filled with thick epipelagic sediments alternating with carbonate turbidites and ash falls and capped with shallow-water reefal and terrigenous debris. Planktonic foraminifera indicate that ages of these rocks range sequentially in a SW direction from the middle Miocene to lower Pliocene. Scanning electron micrographs illustrate 42 species and subspecies of pelagic foraminifera and 13 selected paleoenvironmentally significant aberrant forms.-from Author

Journal of Foraminiferal Research↗
USGS1983

New data on the age of Lepidocyclina in California

During the 1930's and early 1940's, controversy about the age of Lepidocyclina californica and faunas associated with it led to unreconcilable differences of opinion in the attempt to provide a standard stratigraphic framework for Cenozoic rocks of western North America. Two standards with significantly different series age assignments were provided, one based largelyon benthic foraminifers and the other on mollusks and echinoderms. Although both standards have more recently converged in regard to correlating faunas of the Pacific Coast with those in Europe, and although the age of Lepidocyclina has been more firmly established in various countries, the age of the California Lepidocyclina remains in doubt. We report here, for the first time, planktic foraminifers and calcareous nannoplankton associated with the Lepidocyclina . These floras and faunas correlate with the Helicosphaera ampliaperta Zone of Bukrv and Zone N 7 of Blow and indicate that Lepidocyclina californica is probably early Miocene. This revised age removes the basis for the significantly different series age assignments for the Pacific Coast standards.

Journal of Foraminiferal Research↗
USGS1984

The Mohnian-Luisian boundary in the Coccolithus miopelagicus subzone, with new and related species of forminifers.

New information obtained from samples colleced in a 1979 cruise is presented for the Luisian-Mohnian (Miocene) boundary. In some areas of the S California Borderland, the early Mohnian-Luisian boundary apparently occurs within the Coccolithus miopelagicus subzone. To suppor this statement, the location of the samples and a list of the diagnostic foraminifers are provided for each sample in part I of this report. Fifteen species and one variety of new or undescribed benthic foraminifers which were observed in the course of this and other studies of the foraminiferal content of Dart core samples from the S California Borderland are reported and described in part II. The genus Bolivina is represented by 3 new species and 1 species previously undescribed. There are also 2 new species each of Uvigerina, Siphogenerina, Cassidulina, and Ehrenbergina; one undescribed species and a new variety of Megastomella; and one new species each of Epistominella and Concavella. -from Author

Journal of Foraminiferal Research↗
USGS1985

Apertural features and surface texture of upper Paleogene biserial planktonic foraminifers: links between Chiloguembelina and Streptochilus.

Several upper Paleogene species of Chiloguembelina have an internal apertural plate that is very similar to the internal plate typical of the Neogene genus Streptochilus. The type species of Chiloguembelina, C. midwayensis midwayensis (Cushman), however, lacks any internal apertural structure or modifications. Therefore, the following 'Chiloguembelina', which have an internal plate, are assigned to Streptochilus: S. cubensis (Palmer), S. martini (Pijpers) and S. sp.aff. S. martini. -Authors

Journal of Foraminiferal Research↗
USGS1987

Benthic foraminifers on the continental shelf and upper slope, Russian River area, northern California ( USA).

We analyzed benthic foraminifers from 71 surface samples collected from the sea floor of the continental margin. One hundred and six different taxa were identified, and Q-mode factor analysis was used to identify assemblages. Six foraminiferal assemblage factors explain 94% of the variation in the data matrix. The Inner Shelf Assemblage is characterized by Trichohyalus ornatissima, Rotalia columbiensis, Cassidulina limbata, Cibicides fletcheri, Elphidiella hannai and Elphidium sp. 1 and occupies water depths less than 50 m. The Middle Shelf Assemblage is characterized by Nonionella basispinata, Elphidium excavatum and Florilus labradoricus and occupies water depths between 50 and 90 m. A Middle Shelf to Upper Bathyal Assemblage is characterized by Uvigerina juncea, Globobulimina spp. and Nonionella basispinata and occupies depths between about 90 and 450 m. Two overlapping assemblages make up the Upper Middle Bathyal Assemblage and are most abundant between water depths of 500 and 1300 m. They are associated with low- oxygen conditions. The Mid-Bathyal Assemblage is dominated by Uvigerina proboscidea and occurs on the slope at water depths ranging from 1200 to 2500 m. -from Authors

Journal of Foraminiferal Research↗
USGS1987

Benthic foraminifera of the Panamanian Province: distribution and origins.

Two hundred twenty-nine species of benthic foraminifera have been identified from 96 stations representing 33 localities on the eastern Pacific inner continental shelf, ranging from southern Peru to northern Baja California. Their distributions mark nearshore provincial boundaries that are nearly identical with those previously documented from the distribution of ostracodes and molluscs. Thirteen species are characteristic of the Panamanian Province, one is characteristic of the Chilean-Peruvian Province, and one is characteristic of the newly proposed Sonoran Subprovince. Seventeen species (7%) appear to be endemic to the eastern Pacific. Fifty-eight (25%) of the species recognized are disjunct from population centers in the western Pacific, 134 species (59%) are disjunct from modern assemblages of the Atlanto-Caribbean region, and 40 species (17%) are disjunct from both the western Pacific and the Atlanto-Caribbean. The distribution of the remaining 57 species (25%) is poorly documented; we classify them as of unknown origin.

Journal of Foraminiferal Research↗
USGS1987

Maestrichtian benthic foraminifers from Ocean Point, North Slope, Alaska ( USA).

Previous studies of fauna and flora from Ocean Point, Alaska, have suggested ages ranging from Campanian to early Eocene and that these assemblages are either highly endemic or commonplace. I demonstrate that the moderately abundant benthic foraminifers constitute early Maestrichtian boreal assemblages common to Canada and northern Europe. Paleoenvironmental analysis indicates that deposition took place in outer neritic settings (50 to 150m). The Ocean Point benthic foraminiferal assemblages contain species that migrated from the US Gulf Coast, North American Interior and Europe during the Campanian, and from Europe during the Maestrichtian. These faunal affinities suggest that seaways connected the Arctic to the North American Interior and Atlantic during the Campanian and that a shallow seaway connected the Arctic to the Atlantic during the early Maestrichtian. - from Author

Journal of Foraminiferal Research↗
USGS1991

Early evolution of Tubulogenerina during the Paleogene of Europe

The early evolution of Tubulogenerina took place in Europe where eight species occur in lower Eocene to uppermost Oligocene or lower Miocene strata. Species diversity within Tubulogenerina dropped significantly in the early Oligocne; only a single species persisted from the late Eocene, and it became extinct before the end of the early Oligocene. Morphologic changes during the European phylogeny of Tubulogenerina include (1) the development of costate and more complex tubulopore ornamentation, and (2) the change from a single elongated apertural slit with a single toothplate to multiple apertures and toothplates. Three new Tubulogenerina species are described. -from Authors

Journal of Foraminiferal Research↗
USGS1992

Species dominance and equitability: patterns in Cenozoic foraminifera of eastern North America

Species dominance in benthonic foraminifera, represented by percent of the assemblage composed of the single most abundant species, shows little change in observed range of values from shallow into deep-marine waters in 1005 samples from the Gulf of Mexico, Atlantic, and Arctic margins of North America. This finding contrasts with the model that species dominance is highest in shallow-marine environments and decreases offshore into deeper marine waters. Equitability, the relation of all species abundances within an assemblage, also shows little change between the values found in shallow-marine assemblages and those found in assemblages from deeper water environments. Equitability and dominance values found in 421 assemblages from Palaeocene, Eocene, Miocene, and Pleistocene strata of the Atlantic and E Gulf of Mexico coastal plains are similar to the modern values. -from Authors

Journal of Foraminiferal Research↗
USGS1995

Paleocene to Middle Miocene planktic foraminifera of the southwestern Salisbury Embayment, Virginia and Maryland: biostratigraphy, allostratigraphy, and sequence stratigraphy

The Paleocene to Middle Miocene sedimentary fill of the southwestern Salisbury Embayment contains a fragmental depositional record, interrupted by numerous local diastems and regional unconformities. Using planktic foraminiferal biostratigraphy, 15 unconformity-bounded depositional units have been identified, assigned to six formations and seven alloformations previously recognized in the embayment. The units correlate with second- and third-order sequences of the Exxon sequence stratigraphy model, and include transgressive and highstand systems tracts. Alloformation, formation, and sequence boundaries are marked by abrupt, scoured, burrowed, erosional surfaces, which display lag deposits, biostratigraphic gaps, and intense reworking of microfossils above and below the boundaries. Paleocene deposits represent the upper parts of upper Pleocene Biochronozones P4 and P5, and rest uncomformably on Cretaceous sedimentary beds of various ages (Maastrichtian to Albian). Lower Eocene deposits represent parts of Biochronozones P6 and P9. Middle Eocene strata represent mainly parts of Biochronozones P11, P12, and P14. Upper Eocene sediments include parts of Biochronozones P15, P16, and P17. Oligocene deposits encompass parts of Biochronozones. N4b to N7 undifferentiated, P21a, and, perhaps, N4a. Lower Miocene deposits encompass parts of Biochronozones N4b to N7 undifferentiated. Middle Miocene strata represent mainly parts of Biochronorones N8, N9, and N10. Nine plates of scanning electron micrographs illustrate the principal planktic foraminifera used to establish the biostratigraphic framework. Two new informal formine of Praeterenuitella praegemma Li, 1987, are introduced.

Journal of Foraminiferal Research↗
USGS2007

Community structure of foraminiferal communities within temporal biozones from the western Arctic Ocean

Community structure is often an overlooked dimension of biodiversity. Knowledge of community structure, the statistical distribution of the relative species abundance vector, makes possible comparisons and contrasts across time, space, and/or environmental conditions. Our results indicate that species of Arctic foraminifera in age-correlated cores from abyssal depths are each best described by log-series distributions. Using this structural information, we were able to determine that structural stability exists for at least 50 ka. The foraminiferal communities in this study show remarkable concordance, distributional similarity and support the neutral theory of biodiversity.

Journal of Foraminiferal Research↗
USGS2007

Modern foraminiferal facies in a subtropical estuarine channel, Bertioga, São Paulo, Brazil

Numerical analyses of modern foraminiferal abundance and environmental data from the Bertioga Channel (Sa??o Paulo, Brazil) reveal multiple biofacies within an overall paralic setting. Despite its fisheries, mariculture and attraction to tourists, the environmental state of Bertioga Channel remains poorly studied. The present investigation is an attempt to partly fill this gap; the parameters examined include depth, salinity, temperature, organic carbon, sulfur content and bottom sediment type. Muddy sediments with high organic carbon content derived from land drainage are found in the inner parts of the channel, whereas sandy sediment dominates the areas adjacent to the Atlantic Ocean. In the eastern entrance to the channel, sandy sediment contain species of Rotaliida from Facies 1 (including Elphidium discoidale, Elphidium poeyanum, Hanzawaia boueana, Pararotalia cananeiaensis and Nonionella atlantica), reflecting normal marine salinity. Sediments with high percentages of silt and clay in polyhaline and eurybaline environments of the eastern part and Itapanhau?? River contain Facies 2, which includes Ammonia beccarii and Pararotalia cananeiaensis. In the western entrance and central, western and eastern parts, where salinities vary from 18 to 30 psu and the sediments contain both low and high organic carbon, the foraminifera from Facies 3 are dominated by Quinqueloculina milletti, Arenoparrella mexicana, Pararotalia cananeiaensis, Ammonia beccarii, Buliminella elegantissima, Elphidium sp., Elphidium excavatum, Elphidium gunteri and Elphidium poeyanum. In mesohaline and polyhaline waters of the central part, the organic-carbon-rich silt and clay contain Facies 4, which includes Ammonia beccarii, Pararotalia cananeiaensis, Elphidium excavatum and Elphidium sp. Most of organic-carbon-enriched, silty-clay substrates that are subject to the highest fresh-water discharge and high bottom temperatures support two different assemblages: one of mostly Rotaliina and the other mostly of Textulariida (Facies 5 and 6). Facies 5 includes Ammonia beecarii, Elphidium excavatum, Arenoparrella mexicana, Haplophragmoides wilberti, Siphotrochammina lobata, Trochammina inflata and Trochammina sp., all of which are typical of mesohaline sites (mainly Crumau?? and Trindade rivers), and Facies 6 includes Bolivina sp., Ammoastuta salsa, Arenoparrella mexicana, Haplophragmoides wilberti and Trochammina sp., all of which are typical of oligohaline and mesohaline mangrove fringes. The foraminiferal species from the present study are frequently found in paralic environments in Brazil, western Africa and other estuaries around the world.

Journal of Foraminiferal Research↗
USGS2013

Modern salt-marsh and tidal-flat foraminifera from Sitkinak and Simeonof Islands, southwestern Alaska

We describe the modern distribution of salt-marsh and tidal-flat foraminifera from Sitkinak Island (Trinity Islands) and Simeonof Island (Shumagin Islands), Alaska, to begin development of a dataset for later use in reconstructing relative sea-level changes caused by great earthquakes along the Alaska-Aleutian subduction zone. Dead foraminifera were enumerated from a total of 58 surface-sediment samples collected along three intertidal transects around a coastal lagoon on Sitkinak Island and two intertidal transects on Simeonof Island. Two distinctive assemblages of salt-marsh foraminifera were recognized on Sitkinak Island. Miliammina fusca dominated low-marsh settings and Balticammina pseudomacrescens dominated the high marsh. These two species make up >98% of individuals. On Simeonof Island, 93% of individuals in high-marsh settings above mean high water were B. pseudomacrescens . The tidal flat on Simeonof Island was dominated by Cibicides lobatulus (60% of individuals), but the lower limit of this species is subtidal and was not sampled. These results indicate that uplift or subsidence caused by repeated earthquakes along the Alaska-Aleutian subduction zone could be reconstructed in coastal sediments using alternating assemblages of near monospecific B. pseudomacrescens and low-marsh or tidal-flat foraminifera.

Alaska↗
USGS2015

Response of the Miliolid Archaias angulatus to simulated ocean acidification

A common, but not universal, effect of ocean acidification on benthic foraminifera is a reduction in the growth rate. The miliolid Archaias angulatus is a high-Mg (>4 mole% MgCO 3 ), symbiont-bearing, soritid benthic foraminifer that contributes to Caribbean reef carbonate sediments. A laboratory culture study assessed the effects of reduced pH on the growth of A. angulatus . We observed a statistically significant 50% reduction in the growth rate (p < 0.01), calculated from changes in maximum diameter, from 160 &mu;m/28 days in the pH 8.0/pCO 2 air 480 ppm control group to 80 &mu;m/28 days at a treatment level of pH 7.6/pCO 2 air 1328 ppm. Additionally, pseudopore area, &delta; 18 O values, and Mg/Ca ratio all increased, albeit slightly in the latter two variables. The reduction in growth rate indicates that under a high-CO 2 setting, future A. angulatus populations will consist of smaller adults. A model using the results of this study estimates that at pH 7.6 A. angulatus carbonate production in the South Florida reef tract and Florida Bay decreases by 85%, from 0.27 Mt/yr to 0.04 Mt/yr, over an area of 9,000 km 2 .

Journal of Foraminiferal Research↗