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The composition of marine authigenic iron silicates bears subtle evidence of paleo-oceanographic and paleoclimatic conditions. This study focuses on the compositionally unique glauconite within the Early Cretaceous Pariwar and Habur formations in the Jaisalmer Basin and discusses its implications. The Al-glauconite is enriched in TFe 2 O 3 (> 18 wt%), and is considered as Fe-rich Al-glauconite. The X-ray diffraction parameters, the micro-texture, and the K 2 O content reveal an evolved to highly evolved structure of the glauconite. It is abundant in shallow subtidal and tidal- and wave-influenced shoreface facies, and it forms either by the alteration of fecal pellets or as bioclast infillings. Micropaleontological and ichnological proxies confirm the glauconitization in an oxygen-depleted, shallow marine depositional setting. Small-sized (< 1 cm) fodinichnial, pascichnial, domichnial, and repichnial traces, and agglutinated foraminifera ( Bathysiphon) corroborate the oxygen-depleted seawater. The landward expansion of the oxygen minimum zone, leading to oxygen depletion in coastal settings, facilitates the glauconitization in a marginal marine setting. Kaolinite and Fe-Al-smectite react in the presence of excess Fe, forming Fe-rich Al-glauconite on the seafloor. Therefore, the compositionally unique glauconite reflects atypical seawater chemistry with increased elemental influx of Al, Fe, and Mg related to intense continental weathering, kaolinite substrate, and mobilization of Fe 2+ in oxygen-depleted seawater.

Microfossils have been found in most of the Mesozoic basins of Brazil, allowing the establishment of important biozones. Despite being recognized for more than half century in the Barremian from the Recôncavo Basin, the taxonomy of the benthic foraminifera remained unsolved likewise its paleoenviromental implications. In this study, we have applied 2D and 3D imaging techniques to resolve this issue and have identified two agglutinated foraminiferal genera (Glomospirella and Paratrochamminoides) and a new species Paratrochamminoides kaminskii sp. nov. Moreover, based on the taxonomy, few paleoenvironmental insights on the foraminifera-bearing strata are discussed. The occurrence of the typically shallow marine species Glomospirella arctica in the studied section, does not allow the proposition of a marine ingression, since it is not supported by a marine/ transitional association of microfossils. On the other hand, the hypothesis of transport of foraminifera by birds (avian zoocoria) is plausible, although there are no further elements to corroborate it.

A new species of Reophax is documented from the shallow marine settings offshore Brunei Darussalam. The new taxon differs from other recent species of Reophax by its selective agglutination consisting mainly of tests of megalospheric specimens of Amphistegina. Reophax bruneiensis n.sp. differs from other known species in having a selectively agglutinated wall, few numbers of chambers increasing rapidly in size, and a terminal aperture not supported by any neck. This new species possibly acts as detritivore within the bottom sediments characterized by differentiated calcareous bioclasts and clay-sized siliciclasts derived by the river supply.

Eocene foraminiferal assemblages from the Moldova Valley area in the Eastern Carpathians have been investigated with a focus on biostratigraphy and paleoenvironmental changes under the influence of Eocene tectonics. Paleoenvironmental investigations have been carried on two sections using foraminiferal morphogroups, clusters, and diversity analyses. The Eocene assemblages are highly diversified and dominated by deep-water agglutinated foraminifera; rare calcareous benthic and planktonic foraminifera were indentified only in one section. Agglutinated foraminiferal morphogroups are differently represented in the studied sections: while in the first section (GHP) M2c (elongate keeled) and M3b (flattened irregular) morphotypes are lacking, the second section (GHE) includes all the agglutinated foraminifera morphogroups. Bathyal paleoenvironments are indicated by typical deep-water agglutinated foraminifera together with Ammolagena clavata (Jones and Parker). Based on the presence of the agglutinated species Bulbobaculites gorlicensis Wakowska, Reticulophragmium amplectens (Grzybowski), Spiroplectammina spectabilis (Grzybowski) emend Kaminski, and calcareous nannofossils, the age of the deposits has been assigned to the Bartonian (the GHP section) and the Priabonian (the GHE section).

The biostratigraphy of the Outer Carpathians is based mainly on the ranges of agglutinated foraminifera. Species acmes provide the opportunity to enhance and support the existing biozonations. Assemblages of agglutinated foraminifera from the Campanian to Eocene of various tectonic-structural units were analyzed in terms of their qualitative and quantitative occurrence. In this stratigraphic interval, 19 species display significantly increased abundance within a relatively short interval: Caudammina gigantea (Geroch) (upper Santonian–lowermost Maastrichtian), Caudammina ovulum (Grzybowski) (Campanian–Danian), Placentammina placenta (Grzybowski)-Saccammina grzybowskii (Schubert) (upper Campanian–Danian), Caudammina excelsa (Dylążanka) (lowermost Maastrichtian–Danian), Caudammina ovuloides (Grzybowski) (Danian–Selandian), Hormosina velascoensis (Cushman) (upper Danian–Selandian), Praesphaerammina gerochi (Hanzlíková) (Thanetian), Glomospira charoides (Jones et Parker)-Glomospira gordialis (Jones et Parker) (uppermost Thanetian–lowermost Ypresian), Trochammina spp. (upper Thanetian–lower Ypresian), Reticulophragmium amplectens (Grzybowski) (Lutetian–Bartonian), Reophax duplex (Grzybowski)-Reophax “pilulifer” Brady group of taxa (Lutetian–Priabonian), Haplophragmoides walteri (Grzybowski)-Haplophragmoides nauticus Kender, Kaminski et Jones (Lutetian–Bartonian), Spiroplectammina spectabilis (Grzybowski) (Lutetian–Priabonian), “Ammodiscus” latus Grzybowski (Bartonian–Priabonian), Praesphaerammina subgaleata (Vašíček) (Lutetian–Bartonian). The biostratigraphic position and quantitative data of species with increased abundance are presented.

Organic-cemented benthic agglutinated foraminifera are a highly dominant component of flysch-type DWAF assemblages, while agglutinated foraminifera that use calcareous cement are rare or almost absent.However, in mixed assemblages, consisting of both benthic and planktonic forms, the agglutinated foraminiferal assemblages usually include calcareous agglutinants and display higher taxonomic diversity than coeval flysch-type agglutinated foraminiferal assemblages. Late Paleocene – Late Eocene mixed foraminiferal assemblages from 45 samples collected from the Fore-Magura Thrust Sheet of the Polish Outer Carpathians, were examined for taxonomic identification of characteristic agglutinated foraminiferawith calcareous material in their tests. The following 11 species are reported herein: Vulvulina eocaena Montagne, Plectina elongata Cushman and Bermúdez, Gaudryina laevigata Franke, Gaudryina pyramidata Cushman, Arenobulimina d’orbignyi (Reuss), Remesella varians (Glaessner), Dorothia beloides Hillebrandt, Karreriella chapapotensis (Cole), Karreriella subglabra (Gümbel), Clavulinoides havanensis Cushman and Bermúdez, Pseudoclavulina clavata (Cushman) and an additional 10 taxa are left in open nomenclature. The species assigned to Vulvulina, Plectina, Gaudryina and Pseudogaudryinella reveal calcareous material within their tests, though the descriptions of these genera do not always specify this feature. The results of this study reveal higher diversity and abundance of calcareous agglutinated foraminifera occurring in themarly deposits of the Fore-Magura Thrust Sheet in comparison with other units of the PolishOuter Carpathians. The studied group of agglutinated foraminifera with calcareous material may be regarded as a characteristic component of DWAF assemblages indicative of the slope marl foraminiferal assemblages.

The Nariva Formation comprises mostly non-calcareous rocks with few calcareous foraminifera, but it is sandwiched geographically in a narrow (<10 km wide) band between the richly calcareous Brasso and Cipero Formations to the north and south respectively. Sixty-one samples were collected from the Nariva Formation at nine transient exposures along a transect trending NNE-SSW across southwestern Central Trinidad. The sparse planktonic foraminiferal assemblages showed the exposures to range in age between Oligocene and early middle Miocene, though many of the samples were of earliest middle Miocene age and coincident with a tectonically-induced transgressive-regressive cycle in the Brasso Formation. The Nariva assemblage at the most southerly exposure, at which the Nariva and Cipero Formations interfingered, was calcareous and of lower bathyal aspect, containing many Planulina wuellerstorfi. The assemblage at this exposure did not differ statistically between the two formations, and was thus said to be of “Cipero aspect”, although the presence of rare Elphidium sp. in the Nariva parts of the exposure attests to some downslope transport. Recovery from most other exposures was typically small. Richer, predominantly agglutinated assemblages, however, were obtained from the Tarouba Community Centre, Ben Lomond Quarry, Raphael Street, and Tabaquite Heights. The assemblages were of “Brasso aspect”, comprising species illustrated previously from the Brasso Formation. Three exposures were sampled at the Raphael Street site, which covered about ten hectares and had been cleared for development. The rocks at this site are patchily but richly stained with hematite and possible manganese derived from hydrothermal activity. Exposure 1 (13 samples) was subdivided into an almost barren interval (Exposure 1a, 8 samples) and an interval containing abundant Cribrostomoides carapitanus and Trochammina cf. pacifica and lesser Jarvisella karamatensis, Arenogaudryina flexilis and Glaphyrammina americana (Exposure 1b, 5 samples). This assemblage is thought to indicate low dissolved oxygen concentrations at middle to lower bathyal paleodepths. That the Brasso Formation was deposited at neritic to shallower middle bathyal paleodepths, while the Cipero Formation at lower bathyal to abyssal depths, demonstrates that the Nariva Formation was deposited on an eastward-facing paleo-slope. Exposures 2 (9 samples) and 3 (5 samples) are dominated by Simobaculites saundersi Wilson and Kaminski, n. sp., the walls of which do not incorporate calcareous particles. Many samples yielded large quantities of gypsum that, in view of (a) the paleodepth and (b) the rich planktonic foraminiferal recovery from the adjacent Brasso and Cipero Formations, is thought to reflect syndepositional dissolution of foraminiferal calcium carbonate and its precipitation as calcium sulphate. Because both the Nariva Formation and the upper Miocene to lower Pliocene Lower Cruse Member (southern Trinidad) yield primarily organically-cemented agglutinated foraminifera, a comparison is made between them. SHE analysis and different mean values of the Assemblage Turnover Index (ATI) shows the community structures in the two formations to differ. Because there is no sign of hydrothermal activity associated with the Lower Cruse Member, despite their taxonomic similarity we conclude that the agglutinated assemblages in the Nariva and Cruse Formations lived in markedly different paleoenvironments.

Attached epilithic foraminifera constitute an important but overlooked component of the benthic foraminiferal assemblage in the Pleistocene sediment of the central Arctic Ocean. We report 12 types of epilithic foraminifera that have colonised lithic and biogenic grains found in glacial sediments, including representatives of the genera Rhizammina, Hemisphaerammina, Ammopemphix, Diffusilina, Subreophax, Placopsilina, Placopsilinella, Hormosinelloides and Tholosina, accompanied by mat-like and ribbon-like forms of uncertain taxonomic affinity. The attached agglutinated forms appear to be colonisers, adapted to extremely oligotrophic conditions.

Larger agglutinated foraminifera resembling the Cretaceous genus Navarella Ciry and Rat 1951 were recently recovered in Thanetian hemipelagites from the Belluno Basin, northeastern Italy. These lituoids first appear in the basal Thanetian (uppermost calcareous nannofossils Zone CNP 8) and become common in the >500 μm washed residue from the uppermost Thanetian. They abruptly disappear at the Paleocene/Eocene boundary, in coincidence with the extinction of Paleocene small benthic foraminifera (the benthic foraminiferal extinction event - BEE). In order to document the internal chamber arrangement and the agglutinated wall microstructure of the Thanetian lituolids and to compare them with similar individuals recovered from the Upper Cretaceous and Danian strata of the same section, the collected specimens were sectioned and analyzed using a Scanning Electron Microscope (SEM), equipped with an energy-dispersive X-ray spectrometer (EDX). Our results show a typical bi-layered wall microstructure in the Thanetian specimens, whereas the older Maastrichtian and Danian specimens, occurring in the same section, display a single, thicker agglutinated wall. The taxonomy of the Italian lituolids is discussed and compared with similar taxa known from the literature. We describe the Thanetian lituolids as the new genus Neonavarella, which shows an apparently identical external morphology to mono-layered Maastrichtian–Danian specimens but differs in the microstructure of the agglutinated test wall that is bi-layered. The finding of new and well-preserved material from the Paleocene Scaglia Rossa beds of Italy helps shed light on the taxonomy of the still poorly known deep-water larger lituolids.

Despite the importance of the Bering Sea for subarctic oceanography and climate, relatively little is known of the foraminifera from the extensive Aleutian Basin. We report the occurrence of modern deep-water agglutinated foraminifera collected at seven sites cored during Integrated Ocean Drilling Program (IODP) Expedition 323 in the Bering Sea. Assemblages collected from core-top samples contained 32 genera and 50 species and are described and illustrated here for the first time. Commonly occurring species include typical deep-water Rhizammina, Reophax, Rhabdammina, Recurvoides and Nodulina Assemblages from the northern sites also consist of accessory Cyclammina, Eggerelloides and Glaphyrammina, whilst those of the Bowers Ridge sites consist of other tubular genera and Martinottiella. Of the studied stations with the lowest dissolved oxygen concentrations, the potentially Bering Sea endemic Eggerelloides sp. 1 inhabits the northern slope, which has the highest primary productivity, and the potentially endemic Martinottiella sp. 3 inhabits Bowers Ridge, which has the lowest oxygen concentrations but relatively low annual productivity. Martinottiella sp. 3, with open pores on its test surface, has previously been reported in Pliocene to Recent material from Bowers Ridge. Despite relatively small sample sizes, ecological constraints may imply that the Bering Sea experienced high productivity and reduced oxygen at times since at least the Pliocene. We note the partially endemic nature of the agglutinated foraminiferal assemblages, which may at least in part be due to basin restriction, the geologically long time period of reduced oxygen, and high organic carbon flux. Our results indicate the importance of gathering further surface sample data from the Aleutian Basin.