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Global warming threatens the viability of tropical coral reefs and associated marine calcifiers, including symbiont-bearing larger benthic foraminifera (LBF). The impacts of current climate change on LBF are debated because they were particularly diverse and abundant during past warm periods. Studies on the responses of selected LBF species to changing environmental conditions reveal varying results. Based on a comprehensive review of the scientific literature on LBF species occurrences, we applied species distribution modeling using Maxent to estimate present-day and future species richness patterns on a global scale for the time periods 2040-2050 and 2090-2100. For our future projections, we focus on Representative Concentration Pathway 6.0 from the Intergovernmental Panel on Climate Change, which projects mean surface temperature changes of +2.2°C by the year 2100. Our results suggest that species richness in the Central Indo-Pacific is two to three times higher than in the Bahamian ecoregion, which we have identified as the present-day center of LBF diversity in the Atlantic. Our future predictions project a dramatic temperature-driven decline in low-latitude species richness and an increasing widening bimodal latitudinal pattern of species diversity. While the central Indo-Pacific, now the stronghold of LBF diversity, is expected to be most pushed outside of the currently realized niches of most species, refugia may be largely preserved in the Atlantic. LBF species will face large-scale non-analogous climatic conditions compared to currently realized climate space in the near future, as reflected in the extensive areas of extrapolation, particularly in the Indo-Pacific. Our study supports hypotheses that species richness and biogeographic patterns of LBF will fundamentally change under future climate conditions, possibly initiating a faunal turnover by the late 21st century., (© 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

A taxonomic study of the Paleocene larger foraminifera from the Pyrenean basin has led to the description of sixty taxa including two new species: Alveolina korresensis and Valvulineria bacetai. In this work, we present a chronostratigraphic recalibration of the Paleocene Shallow Benthic Zones SBZ 1 to SBZ 4 based on correlation with calcareous nannofossil and planktic foraminifera biozones, all integrated within the stratigraphic framework of Paleocene platform to basin depositional sequences established for the whole Pyrenean domain. The samples were collected in autochtonous and parautochtonous deposits from ten key stratigraphic sections, representative of coastal to platform margin depositional settings. The results from two sections representing base of slope facies with intercalations of calcareous turbidites, which include penecontemporaneous platform-derived biota have been integrated in the study. The regional chronostratigraphic framework is derived from magneto-biochronological studies carried out in the Zumaia section, the global reference section for the Danian-Selandian and Selandian-Thanetian GSSPs. A new calibration of the Paleocene SBZs is proposed. The SBZ 1 is constrained to the first 1.09m.y. of the Paleocene; this first Paleogene biozone lacks distinct larger foraminiferal markers and thus is defined by an association of non-exclusive taxa composed of Valvulineria patalaensis, Stomatorbina? binkhorsti, Planorbulina? antiqua and Bangiana hanseni. The SBZ 2 now appears as the biozone encompassing most of the Danian stage (from ca. 64.9m.a. to 61.6m.a.), and is characterized by the association of Haymanella elongata, Haymanella paleocenica, Kayseriella decastroi, Rotospirella conica, Pyrenerotalia depressa, Elazigina dienii, Ornatononion moorkensii and Paralockhartia eos. The SBZ 2-SBZ 3 boundary coincides with the base of the Selandian stage (ca. 61.6m.a.). The SBZ 3 biozone is defined by the occurrence of Glomalveolina primaeva, Periloculina slovenica, Vania anatolica, Coskinon rajkae, Fallotella alavensis, Cribrobulimina carniolica, Miscellanea yvettae, Miscellanea juliettae, Miscellanites primitivus, Miscellanites minutus, Ranikothalia soldadensis, "Operculina" heberti and Discocyclina seunesi. The SBZ 3-SBZ 4 boundary is now ascribed to ca. 57.2m.a. The SBZ 4 biozone appears characterized by Glomalveolina levis, Alveolina korresensis, Hottingerina lukasi, Daviesina garumnensis, Assilina yvettae, Assilina azilensis and Nummulites catari. The SBZ 4-SBZ 5 boundary is placed at the Paleocene-Eocene boundary event (ca. 56.0m.a.). [ABSTRACT FROM AUTHOR]

The larger foraminifera of the lower part of the Jafnayn Formation outcropping in the Wadi Sayq, in the Paleocene series of the eastern Oman Mountains, have been studied and described in detail. The analysis have allowed us to develop a detailed systematic description of each taxa, constraining their biostratigraphic distribution and defining the associated foraminifera assemblages. The taxonomic study has permitted us to identify each morphotype precisely and describe three new taxa, namely, Ercumentina sayqensis n. gen. n. sp. Lacazinella rogeri n. sp. and Globoreticulinidae new family. The first assemblage is characterized by the presence of Coskinon sp., Dictyoconus cf. turriculus HOTTINGER AND DROBNE, Anatoliella ozalpiensis SIREL, Ercumentina sayqensis n. gen. n. sp. SERRA-KIEL AND VICEDO, Lacazinella rogeri n. sp. SERRA-KIEL AND VICEDO, Mandanella cf. flabelliformis RAHAGHI, Azzarolina daviesi (HENSON), Lockhartia retiata SANDER, Dictyokathina simplex SMOUT and Miscellanites globularis (RAHAGHI). The second assemblage is constituted by the forms Pseudofallotella persica (HOTTINGER AND DROBNE), Dictyoconus cf. turriculus HOTTINGER AND DROBNE, Lacazinella rogeri n. sp. SERRA-KIEL AND VICEDO, Azzarolina daviesi (HENSON), Keramosphera? cf. iranica RAHAGHI, Lockhartia haimei (DAVIES), Lockhartia retiata SANDER, Sakesaria trichilata SANDER, Kathina delseota SMOUT, Elazigina harabekayisensis SIREL, Daviesina khatiyahi SMOUT, and Miscellanea juliettae LEPPIG. The first assemblage can be considered to belong to the Shallow Bentic Zone SBZ2 (early Selandian age), and the second assemblage to the SBZ3 (late Selandian-early Thanetian age).This paper shows, for the first time in the Middle East area, a correlation between the Selandian larger foraminifera and planktonic foraminifera biozones. [ABSTRACT FROM AUTHOR]

A rich larger foraminifera assemblage from the Eocene carbonates of the south Sabzevar region (Now-Deh section) in central Iran indicates a late Ypresian to early Lutetian age. Nine species of Alveolina d’Orbigny are studied for systematics and biostratigraphy. The assemblage includes A. minuta, A. decastroi, A. cremae, A. cremae elongata, A. decipiens ayrancensis, A. celali, A. rugosa, A. cuspidata, A. frumentiformis. We have also found nummulitids (genus Nummulites and Assilina) and orthophragmines identified as N. campesinus, N. praediscorbinus, A. placentula, A. praespira, A. reicheli, A. ex. intrec. laxispira-maior and Discocyclina archiaci bartholomei. The recovery of Alveolina cremae elongata, A. decipiens ayrancensis, A. celali, A. rugosa, A. cuspidata and Assilina praespira has permitted for the first time to extend their geographical distribution outside of the classical peri-Mediterranean area to the central Tethys regions. The obtained biostratigraphy points to the Shallow Benthic Zones SBZ11 to SBZ13, indicating the occurrence of a Lower-–Middle Eocene carbonate system. Part of the age model is supported by the calcareous nannofossil biostratigraphy that belong to the NP14b and CNE8 biozones, recorded from the central portion of the studied section. Issues regarding the application of the SBZ into the Middle East domains are discussed in terms of relative stratigraphic position and biogeographic dispersal of some significant Alveolina species. [ABSTRACT FROM AUTHOR]

The Nummulites amakusensis Yabe and Hanzawa-- N. junbarensis Matsumaru -- N. hongoensis Hanzawa -- Discocyclina pratti (Michelin) Assemblage (generic term: Amakusa Assemblage) zone of lower Eocene (Ypresian)/middle Eocene (Lutetian), assigned to Letter Stage a2 and the P9 planktonic foraminifera zone in the Philippine Archipelago, is recognized in 20 stratigraphically positioned samples from the Akashimisaki Formation in the Amakusa Islands, Kyushu district Japan, and also in three samples from the Tachien and Meichi Sandstones, Hsuehshan Range, central Taiwan, based on age diagnostic larger foraminifera of five genera and 15 species, together with associated planktonic foraminifera. At the Bozubana locality (station No. 3), Amakusa Islands, unusual white clastic limestone layers in fault blocks of theAkashimisaki Formation yield reworked late Paleocene (Thanetian) larger foraminifera and Late Cretaceous (Maastrichtian) planktonic foraminifera in the Bozubana Thrust Fault zone, which was activated by the Peri Tunghai TectonicMovement in the Ryukyu Arc after the Eocene formations were deposited. The Amakusa Assemblage is proposed for a key regional framework in the eastern Tethys indicating the late Early Eocene (Ypresian)/early Middle Eocene (Lutetian) based on zone P9 and Letter Stage a2. [ABSTRACT FROM AUTHOR]

The rock units in the Gawran Gorge, Sagirma Mountains (from the High Folded Zone), near the Sulaimaniyah city, in the Kurdistan Region, NE Iraq, were investigated in order to describe and biostratigraphically date the sedimentary succession. Twenty-seven species of larger benthic foraminifera were identified belonging to 16 genera. Several other fossil groups were also recognized, including echinoid, bryozoan, bivalve, gastropods and coral remains. Two biozones were recognized--the Praerhapydionina delicata-Austrotrillina asmariensis/Peneroplis evolutus Assemblage Zone and the P. delicata/Austrotrillina howchini Interval Zone, which indicate a late Oligocene-lowermost Miocene age for the succession. This section was correlated to the surrounding successions having a similar age in the High Folded Zone of Iraq, and to sediments in other countries, so as to indicate the wider distribution of the lithostratigraphic unit. [ABSTRACT FROM AUTHOR]

Paleocene-Eocene aged sediments from the east of Tuz Gölü Basin (Central Türkiye) provide significant data for foraminifera contents and their paleoenvironmental clues. They are important in revealing the stratigraphy of the region and the Paleocene-Eocene geological history of Türkiye. The sediments, composed mainly of carbonates, are known as Karapınaryaylası Formation. In this formation, benthic foraminifera representing SBZ2 to SBZ12 biozones corresponding to the Selandian-Late Cuisian time interval were identified in ten measured stratigraphical sections. The zonal interval from the E7 Zone (late Ypresian) to the E10 Zone (Lutetian) is characterized by the marker species of planktonic foraminifera defined in the clayey limestones from the uppermost part. The studied formation is divided into four main facies and eleven sub-microfacies types. The clayey limestone levels of the Karapınaryaylası Formation, which generally starts with a transgressive sequence, contain abundant planktonic foraminifers, while the lithologies of grainstone, packstone and wackestone are rich in benthic foraminifers. Benthic foraminifer assemblages indicate different paleoenvironments from lagoon to back-bank, bank and fore-bank. The obtained foraminiferal data show the Selandian-Lutetian age range and various paleoenvironments from the lagoon to the open sea. [ABSTRACT FROM AUTHOR]

Simple Summary: The tests of the unicellular protozoan Nummulites distans (Cenozoic era, Paleogene period) were studied using X-ray diffraction. In addition, the images obtained using X-ray microtomography and scanning electron microscopy were analyzed. A high degree of the calcite crystal orientation ordering that the test consists of has been revealed. It is higher than that of calcite from the shells of the bivalve mollusk Placuna placenta, whose shell is formed by a special multicellular tissue. So, it is found that already unicellular organisms have strict control over the crystal arrangement. Unicellular protozoa form calcium carbonate tests. It is important to understand the features and mechanisms of its formation. This may shed light on the processes of shell formation in metazoans. One of the most important characteristics of the Protozoa carbonate test is the degree of crystal ordering that can be described by crystallographic texture. The crystallographic texture data of calcite in the foraminifera Nummulites distans (Deshayes) test from the Eocene deposits (Cenozoic, Paleogene) of the Crimea Peninsula are obtained using X-ray diffraction. A very strict orientation of the crystals is revealed. The calcite texture sharpness is several times greater than in the shells of the bivalve mollusk Placuna placenta (Linnaeus), measured by the same method. It also exceeds the crystallographic texture and sharpness of the same mineral in the shells of the bivalves of Mytilus galloprovincialis (Lamarck), studied by neutron diffraction. It is concluded that a high level of control during test formation is already characteristic of protozoa. Studying the processes involved in the formation of a very sharp crystallographic texture can become an important direction for creating nature-like materials with desired properties. [ABSTRACT FROM AUTHOR]

A key but challenging task for biostratigraphers is to provide a biozonal/bioevent framework for geological correlation. Species of Larger Benthic Foraminifera (LBF) are important biostratigraphic markers in depositional environments where classical biostratigraphic fossils such as planktonic micro- and macrofossils are rare or absent - e.g., tropical-subtropical shallow water platforms. However, a lack of taxonomic rigour in identifying some LBF species, together with a lack of good age-calibration of their occurrences, has given rise to artificially extended biostratigraphic and paleogeographic ranges for many taxa, diluting their usefulness. In this study, the occurrences of Cenomanian LBF belonging to a "planispiral morphogroup", both agglutinated and calcareous, have been critically evaluated to determine (i) identity; (ii) stratigraphic range; and (iii) palaeogeographic distribution. Since the last major review of the group in 1985, a voluminous literature has appeared reporting occurrences and adding new taxa. An extensive review of some 600+ published items on Cenomanian planispiral LBF - mostly published after 1985 - and a critical review of the confidence in species identification and age-calibrations therein, has led us to identify 39 taxa (three in "open" status) which appear to have distinct identity. The vast majority of these records are from Neotethys although some also occur in (or are endemic to) the Caribbean/West Atlantic and the Eastern Pacific. The quality of the published taxonomic data is variable and many published records based on identity can be discounted or termed "unconfirmed". Likewise, many records (confirmed or otherwise) are poorly age-calibrated due to lack of corroborating biostratigraphy or chemostratigraphy, or by using circular reasoning. We summarise and illustrate the main defining characteristics of each taxon and their possible confusion species, including new taxa described since the mid-1980s. We publish new, more confident, age-ranges for these taxa - confirmed by identity and/or age-calibration - and identify where published range data may be unreliable. Paleogeographic distribution maps for each taxon are also provided. Particular stratigraphic issues around the Cenomanian-Turonian boundary are observed due to the difficulty of identifying that boundary, or its preservation, in shallow marine carbonate settings. Although most Cenomanian planispiral LBF are somewhat long-ranging, an increase in diversity throughout the middle - late Cenomanian has shown potential for biostratigraphic resolution to at least substage level using this group. Integration of the planispiral taxa with other LBF morphogroups, after similar treatment, will yield even higher biostratigraphic resolution of Cenomanian LBF and provide a sound basis for biozonation (both local and global), correlation, and age calibration. [ABSTRACT FROM AUTHOR]

Paleogene sedimentary deposits are exposed in several localities along the extended Thrace Basin in the Greek territory. One of the best sites in terms of preservation, richness and type of sediment occurs along the coastline of Fanari village (SW of Komotini city). Two outcrops, which consist of upper Eocene shallow marine clastic sediments, were sampled to analyze the full spectrum of larger benthic foraminifera (LBF) that comprises a rich and diverse assemblage of orthophragmines (Discocyclina, Orbitoclypeus and Asterocyclina), nummulitids (Nummulites, Assilina, Operculina, Heterostegina and Spiroclypeus), and other benthic taxa (e.g., Silvestriella, Pellatispira, Fabiania, Sphaerogypsina, etc.). Adetailed systematic description of LBF from Fanari is presented, which refines the biostratigraphic age of SBZ (Shallow Benthic Zone) 20 corresponding to the late Priabonian for the whole sequence. Twenty-four taxa among which six at (chrono)subspecies level belonging to twelve genera were identified and morphometrically analyzed for the first time from Greece. The LBF assemblage is characterized by the constant presence of Nummulites fabianii almost throughout the whole sequence. The most abundant species are Pellatispira madaraszi and Spiroclypeus carpaticus, though they occur in the upper part of the sequence along with orthophragmines. The foraminiferal distribution in the sequence enables paleoenvironmental observations and the reconstruction of the evolution of the Fanari area. Three main depositional marine shelf facies are distinguished at the shallow upper foreslope of the carbonate platform, making the Fanari section a key area not only of latest Priabonian but also of outer shelf biofacies. [ABSTRACT FROM AUTHOR]

Eocene larger benthic foraminifera including orthophragmines, nummulitids and alveolinids from the Jahrum and Pabdeh formations in the Zagros region are presented. The studied 20-m-thick stratigraphic interval contains, Asterocyclina Gümbel 1870, Nemkovella Less 1987, Orbitoclypeus Silvestri 1907, Discocyclina Gümbel 1870, Nummulites Lamarck 1801, Assilina d’Orbigny 1826 and Alveolina d’Orbigny 1826. This larger benthic foraminiferal assemblage testifies for the shallow benthic zones (SBZs) 15 to 17, which ranges from the middle Lutetian up to the early Bartonian. Further micropaleontological analysis made on intercalated planktonic-rich levels helps calibrate the larger foraminifera biostratigraphy, demonstrating a correlation with the E11 biozone. This confirms that the chronostratigraphic calibration of the SBZs made by previous authors for the peri-Mediterranean area can, through the middle Lutetian to the early Bartonian, be applicable in the Middle East as well [ABSTRACT FROM AUTHOR]

Here, we revise and update the biostratigraphy of larger foraminiferal assemblages in three sections of the Priabonian Sanetsch Formation in the Helvetic Nappes of theWestern Swiss Alps: The Sex Rouge (SE) and the Sanetsch Buvette (SA) sections in the Wildhorn Nappe Complex, and the Col des Essets (ETS) section in the most external Morcles Nappe. In the SE and SA sections, the Tsanfleuron and most of the Pierredar Limestone members of the formation are assigned to SBZ 19 (early Priabonian), while the uppermost part of the formation is assigned to SBZ 20 (late Priabonian). In the external ETS section the entire Sanetsch Formation contains assemblages characteristic of SBZ 19, suggesting an earlier, middle-late Priabonian onset of the hemipelagic Stad Formation (“Globigerina Marls”). Since it was established in 1998, the Shallow Benthic Zones (SBZ), a biozonation based on larger foraminifera, has been a useful tool in the biostratigraphy of the Paleogene. Biozonation proposals for the late middle-late Eocene are based mainly in biometrical subdivision of lineages of nummulitids and orthophragmines, which requires measurements in oriented sections of isolated specimens. Here, we define previously unreported taxa from the Sanetsch Formation, which are considered characteristic for the Priabonian. They are easy to identify in random sections and thus useful biostratigraphical markers. We also describe a new orthophragminid genus, Virgasterocylina n. gen. (Orbitoclypeidae) characterized by the presence of rods, radial thickenings of calcite along ribs; a new species of Rotorbinella, R. epardi n. sp., and a new genus and new species of difficult suprageneric attribution, Sanetschella indeprensa n. gen., n. sp. We add the new taxa to the larger foraminiferal association characterizing the Priabonian (SBZ 19–20). The revision of the literature, together with our own sample collections revealed that these new taxa occur in Priabonian rocks from different basins in the western Tethys. Virgasterocylina n. gen. also occurs in the Caribbean bioprovince in the middle and upper Eocene. In the western Tethys, Virgasterocylina ferrandezi is subdivided into two subspecies, V. f. ferrandezi (Özcan and Less) and V. f. lessi n. ssp., which characterize the SBZ 19 and 20 biozones respectively. [ABSTRACT FROM AUTHOR]

Arelatively diverse assemblage of larger benthic foraminifera from the Asmari Formation is described based on the recovered samples from two subsurface sections, offshore and onshore, southern Iran. Due to its position in the Tethyan Seaway between the Mediterranean and Indo-Pacific, the Zagros belt as a part of the Middle East has high significance in palaeobiogeography. The fauna is dominated by both hyaline perforated and porcelaneous forms. Eight species of larger benthic foraminifera are described, including Nummulites fichteli, N. vascus, Operculina complanata, Archaias operculiniformis, Praerhapydionina delicata, Austrotrillina striata, Peneroplis thomasi, and P. evolutus. The presence of N. fichteli and N. vascus in the absence of lepidocyclinids indicates the SBZ 21 Zone referring to a short time span restricted to early Rupelian. [ABSTRACT FROM AUTHOR]

Small reticulateNummulites are found across the Eocene shallow marine deposits of the Paris Basin, Belgium, as far north as northern Germany and southern United Kingdom. Only two isolated instances of Nummulites at higher latitudes than this are known, from the Rockall bank and Wyville-Thomson ridge in the north Atlantic, and no Nummulites have been reported from the Nordic North Sea Basin – until now. Here Nummulites planulatusis described within a glacial erratic dredged from Jyske Rev in the Danish North Sea of likely Ypresian age. Whilst the specimen is not in situ, it indicates that populations ofNummulites were living further north in the North Sea region than previously known. This range expansion may have been facilitated by the hyperthermal events of the early Eocene. [ABSTRACT FROM AUTHOR]

The mean values of the grade of enclosure of the protoconch by the deuteroconch (Ai), the number of adauxiliary chamberlets (C), the number of annuli within 0.5 mm from the embryonic apparatus (N05) and the degree of stolonic distalization (FD5) were evaluated for several Nephrolepidina populations from the western Mediterranean. Data from two new populations were added to the various populations biometrically investigated in the last decades. The routinely employed Ai and C indexes alone seem to be not sufficient to provide biostratigraphic constraints for each Nephrolepidina chronospecies, whereas N05 appears to be dependent to the embryonic size. By including the index FD5, and thus the concept of neanic acceleration, it becomes possible to clearly separate the different chronosubspecies of Nephrolepidina from the Mediterranean bioprovince. Nephrolepidina praemarginata praemarginata is restricted to the late Rupelian SBZ22A. N. pramarginata elenamoroi n. ssp. is erected for those early Chattian (SBZ22B) populations with 32%mean<42%. N. morgani, characterised by 42%mean<50%, stands as a long-ranged species, spanning from the whole Chattian to the lowermost Aquitanian. N. tournoueri antonioi n. ssp. marks the Aquitanian (SBZ24) and is characterised by Aimean >45% and 50%mean<55%. N. tournoueri tournoueri characterises the Burdigalian (SBZ25), with Aimean>45% and FD5mean>55%. [ABSTRACT FROM AUTHOR]

The benthic foraminifera assemblage has been described in the limestones outcropped inKurtalan and Eruh district of Hoya formationwhich is one of autochthonous units of Arabian Platform (SE Turkey). From the two measured sections, one of them has rare fossil content due to dolomitization (DH-Dodan section), while the other is fairly remarkable in terms of fossil content (EH-Eruh section). The foraminiferal assemblages are represented by Asterigerina rotula (Kaufmann), Operculina ex. gr. gomezi Colom and Bauzá, Victoriella conoidea Rutten, Amphistegina sp., Elphidium sp., Peneroplis sp., Carpenteria sp., Stomatorbina sp., miliolid and rotaliid forms and echinoderms, coral fragments in the Dodan section. The foraminiferal assemblages are represented by Nummulites biedai Schaub, Nummulites maximus d'Archiac, Nummulites perforatus de Montfort, Nummulites postfossulatus Sirel and Deveciler, Nummulites praeaturicus Schaub, Assilina exponens (Sowerby), Sphaerogypsina globulus (Reuss), Asterigerina rotula (Kaufmann), Lockhartia cf. hunti Ovey, Neoratlia sp., Operculina sp., Discocyclina sp., Asterocyclina sp., Lockhartia sp., Lenticulina sp., miliolid-rotaliid forms and echinoderms in the Eruh section. The fossil assemblage described shows that the limestones are of Lutetian-Bartonian and this assemblage indicates a very shallow marine deposition environment. This study provides biostratigraphic and stratigraphic data that help to reassess the Eocene geological evolution of the region. Paleobiogeographically, larger benthic foraminiferal assemblages recorded on carbonate platforms in southeastern Turkey show an affinity to Arabian and Middle Eastern platforms. [ABSTRACT FROM AUTHOR]

In the current study, biostratigraphy and paleoecology of the Anah Formation have been investigated. The study area is located in the Sulaimanyah Governorate, Kurdistan Region, Northeast Iraq where the Darzila section has been sampled. Twenty-five species of larger foraminifera and skeletal fragments of coral, echinoid spine, pelecypods, and gastropods are described in seven samples collected from the Darzila section. Based on the distribution of the larger-benthic foraminifera and other skeletal grains, two assemblage biozones of the Late Oligocene – Early Miocene age have been recognized. According to the paleoecological parameters, such as temperature, nutrients, depth, and salinity in the study area, the Anah Formation has deposited the euphotic zone, abundant imperforate foraminifera are present, sub-tropical waters under oligotrophic to mesotrophic middle ramp environment with normal to a higher salinity inner ramp setting and at water depths that ranged from 40 m to 80 m, and a temperature about 18 – 25 ºC. [ABSTRACT FROM AUTHOR]

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The presence of a pseudokeriothecal wall structure is traditionally given a generic or even higher taxonomic status (in association with other features). A new trochospirally coiled taxon displaying a thick wall with pseudokeriotheca and a central siphon (hollow columella) is herein described as Siphopfenderina gen. nov. Such a taxonomic reappraisal is based on original figures and description of Arenobulimina geyikensis Solak. It is herein included within the Pseudopfenderininae due to its primitive "pfenderinid"-like morphology. Siphopfenderina geyikensis (Solak) comb. nov. was described from Aptian neritic Urgonian-type carbonates of the Taurides (Turkey) and said to be the only species of the genus Arenobulimina Cushman (family Ataxophragmiidae) especially due to such a type of wall structure. Arenobulimina is a typical (outer) shelf taxon, smaller in size, and with a thin and typically coarsely agglutinated wall. Other occurrences of Siphopfenderina gen. nov. are described in open nomenclature from the Aptian of Spain and Central Iran, as well as the Upper Cretaceous of Serbia, Croatia and Iran. Arenobulimina cochleata Arnaud-Vanneau from the Lower Cretaceous of France is assigned to Siphopfenderina herein. The taxonomic discrimination of these other species might be related to size and morphology criteria that requires further research. [ABSTRACT FROM AUTHOR]

New field observations and discovery of calcareous nannofossils and planktonic foraminifera from the 'shallow-marine' Çayraz Formation (Haymana Basin, Central Anatolia), a contributing Eocene section to the shallow benthic zonation (SBZ) in the Tethys, allow us to revise its stratigraphy and establish an integrated biostratigraphic scheme for the first time. The hemipelagic marls in the uppermost part of the Eskipolatlı Formation that underlies the Çayraz Formation yielded nannofossil assemblages of Zone CNE3, pinning down the initiation of the Çayraz shelf system into the 'middle' Ypresian. The prominent marly part (Member B) between the carbonate-clastic packages of the Çayraz Formation with prolific occurrences of larger benthic foraminifers (LBFs) (Members A below and C above) yielded calcareous nannofossils suggesting Zone CNE6 (late Ypresian). We show that the mixed carbonate-siliciclastic sequence with abundant LBFs in the upper part of the formation (Member C) is overlain by newly discovered hemipelagic marls (here named as Member D). These marls yielded calcareous nannofossils indicating Zone CNE9 and CNE10 for the lower and Zone CNE12(?Lutetian) for the upper samples. The same beds yielded planktonic foraminifers indicating Zone E8 for the lower and Zone E9 for the upper samples. We conclude that shallow-marine sedimentation in the Çayraz section ended in the 'middle' Lutetian, challenging the previous Bartonian records by LBFs. A new lithostratigraphic scheme consisting of four members with distinctive lithological and biotic characteristics is proposed for the Çayraz Formation: two main shelf systems (Members A and C), each followed by deep-marine sedimentation (Members B and D). [ABSTRACT FROM AUTHOR]

This study investigates the changes in paleoenvironmental conditions in the northern branches of the Neo-Tethys by employing geochemical proxies and shell data of larger benthic foraminifera (LBF) located in central Cappadocia. Three measured stratigraphic sections are studied from the Altipinar Formation (Boztepe Member), which is dated as middle Eocene. Three genera and five specieswere recorded as a result of the paleontological analyses, namely, Alveolina sp., Assilina exponens, Nummulites aturicus, Nummulites maximus and Nummulites perforatus. Composed of clayey sandy limestones, the Boztepe Member is represented by SBZ (Shallow Benthic Zones) 16-17 (late Lutetian/early Bartonian). In the Cappadocia region, a warming event was characterized by a temperature increase of 3°C to 4.5°C, and the warming started after 41.0 Ma (younger than the Lutetian /Bartonian boundary). The peak warming occurred around 40.0 Ma (early Bartonian). This period corresponds to the Middle Eocene Climatic Optimum (MECO), which was a significant global warming event. The findings of this study are confirmed by numerous studies that the global warming event occurred in the middle Eocene (between 41.8 and 39.7 Ma.). Additionally, while paleoenvironmental changes had no effect on the shell shape of Assilina exponens, they had a significant effect on the shell shape of Nummulites perforatus. The diameter/thickness ratio of benthic foraminifera tends to be smaller in shallowconditions than in deep conditions. Thiswas observed as their shell shapes becamemore spherical. [ABSTRACT FROM AUTHOR]

Burdurina selandinica Sirel from Paleocene carbonates of the Golbui section of Central Iran is reported and discussed. The stratigraphic position of foregoing succession is consistent with the previous studies depending on the faunal assemblage of the Selandian–early Thanetian, namely Sistanites iranicus Rahaghi, Anatoliella sp., Haymanella paleocenica Sirel, Coscinospira prima Schlagintweit et al., Miscellanea cf. yvettae Leppig, Elaziginadienii (Hottinger), Idalina sinjarica Grimsdale,Pachycolumella acuta Septfontaine et al., Pachycolumella elongata Septfontaine et al., Rotospirella conica (Smouth). After the latest reorganization on Shallow Benthic Zones (SBZs) of the Paleocene, two stages correspond to SBZ3. Three predominant microfacies types including coral-coralline algal framestone, bioclastic foraminiferal-peloidal grainstone-packstone and coral floatstone were recognized in the studied section. The microfacies gradients within the succession and paleoenvironmental analysis suggest deposition in a shallow-marine ramp environment that is located in a global carbonate platform stage I from the middle paleolatitude. [ABSTRACT FROM AUTHOR]

The biostratigraphic range distribution of larger benthic foraminifera (LBF) from the eastern part of Neo-Tethys in the Kohat Basin of Pakistan is compared with the Western and Central Neo-Tethys. The results are used to establish the migration pathways of LBF for the paleogeographic reconstruction of the Neo-Tethys that existed in the Paleogene. This comparison across the Neo-Tethys revealed that LBF species are mostly confined to the Gondwanan (Iran, Iraq, Pakistan, India, Indonesia) and Laurasian-derived blocks (Italy, France, and Spain), with only a few on the margin of the Gondwanan continents (Oman). [ABSTRACT FROM AUTHOR]

An important shallow marine deposit is described and illustrated with focus on the systematics and biostratigraphy of larger foraminifera from three stratigraphic sections of the Becirman Formation from the Batman and Siirt regions (Southeastern Turkey). A quite diverse association, mostly dominated by rotaliids (11 species belonging to 7 genera) and subordinate porcelaneous and agglutinated taxa, is documented as well. The fossil assemblage, including Elazigina dienii, Rotospirella conica, Praelockhartia cf. neoakbari, Cuvillierina cf. sireli associated with Mardinella daviesi and Idalina sinjarica, indicates the late Danian SBZ2. The abundance of rotaliids is linked, in this time frame, to the recovery of the shallow benthic communities after the K/Pg extinction including increase of surface water temperatures and oligotrophy. This was possibly due to the climatic warming recorded at the end of the Danian (Latest Danian Event), thus promoting a rapid adaptative radiation of rotaliids at genus rank. [ABSTRACT FROM AUTHOR]

Rotaliids are one of the groups of larger foraminifera that quickly recolonized the shallow-water environments after the mass extinction at the end of the Cretaceous. Here we present a summary of the state of the art about their stratigraphic distribution and diversity across the Paleocene and Eocene epochs. Our data suggest that their differentiation at the genus level was very rapid and reached its maximum in the upper Danian SBZ2. Specific diversification, instead, culminated in the upper Thanetian SBZ4, with a second peak during the Cuisian (=upper Ypresian). Successively, the rotaliid diversity definitely declined, whereas other groups of larger foraminifera, and especially Alveolina and Nummulites, became more widespread and flourished with a large amount of species, up to the lower Bartonian SBZ17, when a final drop in rotaliid diversity is recorded. These major changes appear strictly linked to climate warming events such as Late Danian Event (LDE, generic diversification of rotaliids), Paleocene-Eocene Thermal Maximum (PETM, faunal turnover followed by abrupt decrease in both generic and specific diversity), Early Eocene Climatic Optimum (EECO, increase in number of K-strategists under oligotrophic conditions) and Middle Eocene Climatic Optimum (MECO, ultimate drop in diversity and competition with other larger foraminifera). [ABSTRACT FROM AUTHOR]

The foraminiferal contents of the Paleocene-Eocene successions were examined in two sections; at the southern and northern flanks of Chenareh anticline, Lorestan Zone. The Paleocene-Eocene in northern flank was subdivided into three formations from older to younger: Taleh Zang, Kashkan, and Shahbazan formations. During this time, sedimentation of the Paleocene-Eocene Pabdeh and Shahbazan formations took place in the southern flank of Chenareh anticline. Four biostratigraphical zones were defined in Pabdeh Formation as a result of summarizing available data on the taxonomy, stratigraphical range and occurrence of planktic foraminifera, ranging in age from Late Danian to Early Ypresian. The zones are: Praemurica uncinata Interval Zone (P2); Morozovella angulata-Igorina pussila Interval Zone (P3); Globanomalina pseudomenardii Total Range Zone (P4); Morozovella velascoensis Interval Zone (P5). The Taleh Zang Formation and upper part of the Pabdeh Formation contain a rich and diverse assemblage of alveolinids, and nummulitids (Nummulites, Assilina). Their assemblages, referred to SBZ 6, 7 and SBZ 8 (Early Ypresian). The Shahbazan Formation has no index fossils, and it was attributed to Lutetian in age, based on stratigraphic position. [ABSTRACT FROM AUTHOR]

The age and evolution of paleoenvironmental conditions in the Oligocene (Baba Formation) from the Bai-Hassan Well-4 section were studied from the distribution of Large Benthic Foraminifera (LBF), microfacies, and paleoecology. We identified 30 species from 21 genera of Large Benthic Foraminifera (LBF) in addition to corals and algae with remains of mollusca and echinoid spines, belonging to two assemblage zones which are Nummulites vascus, Nummulites fichteli Assemblage Zone and Lepidocyclina (Eulephidina) dilatata—Nummulites vascus, Nummulites fichteli Assemblage Zone. The Baba Formation spans Late Rupelian-to-Early Chattian age in the studied section. Bai-Hassan Well-4 section was subdivided into three carbonate microfacies from the lower to the upper part: fine-to-very coarse bioclastic larger foraminiferal wackestone–packstone (MF1), fine-to-very coarse bioclastic larger foraminiferal packstone (MF2), and fine-to-coarse bioclastic larger foraminiferal packstone–grainstone (MF3). The main depositional environment of the Baba Formation from the lower to the upper art of the studied section is represented by outer ramp starting from open shelf lagoon, and it was deposited from subtropical to a tropical environment from, the lower part to the middle and the upper part of the studied section, with mesotrophic-to- oligotrophic conditions, open marine to shallow and restricted environments with normal to higher water salinity (34–50 ‰), and mesophotic-to-oligophotic conditions of soft-to-hard sediments. [ABSTRACT FROM AUTHOR]

Abstract: The current available Shallow Benthic Zones (SBZs) calibration based on larger foraminifera is now being improved for the Paleogene Period. In this work, the San Pelegrín section in the External Sierras, shows new magnetostratigraphic and biostratigraphic information from the Southwestern Pyrenean basin, where the larger thickness of the shallow marine platforms were developed. This environment represents the appropriate frame to calibrate the SBZ scale. Moreover the magnetostratigraphic data can be correlated with biostratigraphic data obtained directly at the same section, avoiding limitations of previous correlations. The San Pelegrín section presents 530m of Ypresian and Lutetian rocks; 169 sampled levels for magnetostratigraphic purposes have been studied, a fact that guarantees the independence and resolution of this record. Thermal and alternating field demagnetizations were carried out to unravel the characteristic remanent magnetization, and the orthogonal diagrams show stable normal and reverse polarity directions. Three pairs of magnetozones were found along the section enabling to define a robust and reliable local polarity sequence correlated with chrons C23, C22, C21n and C20r. The biostratigraphic study distinguished three Shallow Benthic Zones from SBZ11 to SBZ13. The combination of magneto and biochronologic scales is very useful to improve and to accurate the available shallow benthic zone calibration for this time gap, especially for the SBZ11 zone. Now the base of SBZ11 can be located, at least, in 50.96My, because the association is still present at the top of C23n. This data is older than previously thought from existent scales. On the other side, the SBZ11 top falls within chron C22n. The occurrence of a sedimentary hiatus between C22n and C21n prevents an accurate calibration of the SBZ12 top, but our profile proves the relation of SBZ12 with C22n as well. Finally the SBZ13 zone falls within the limits of recent recalibrations (C21n to C20r). [Copyright &y& Elsevier]

Abstract: In this paper, we present a chronostratigraphic calibration of the shallow benthic zones (SBZs) of larger foraminifera during Lutetian times based on new magnetostratigraphic data (Isuela section) and two new densely sampled biostratigraphic sections (Isuela and Gabardiella). These sections are located in the External Sierras (Southern Pyrenees) and represent an ideal location to avoid previous chronostratigraphic problems. 1) They belong to a shallow carbonate shelf environment with abundant larger foraminifera, which ensure the reliability of SBZ data. 2) The time span covers almost the entire Lutetian interval. 3) The profiles are sufficiently long to establish trustworthy local scales, both the SBZs (520m and 760m in Isuela and Gabardiella respectively) and the paleomagnetic local polarity sequence (LPS) (520m). 4) The excellent outcropping conditions also permit a detailed paleomagnetic and biostratigraphic sampling to be performed. The LPS at the Isuela section was built after sampling every 2.6m. In total, more than 359 samples were thermal (244) and alternating field (115) demagnetized. Characteristic remanent magnetization (ChRM) usually dropped at 560°C. Only 43% the samples (359 demagnetizations) gave reliable directions (high quality) for the LPS. A further short section (Gas line) was also cored (38 samples in 90m) to obtain more detailed data for the upper part of the section. At the Isuela section, the results allow three pairs of trustable magnetozones to be assembled within the Lutetian. A further 255 samples were taken for biostratigraphic purposes, 55 sites at the Isuela and 52 at the Gabardiella sections being determinant. This density enabled a thorough study of changes in fossil associations to be performed. Assuming a constant accumulation rate within the chron boundaries, absolute ages have been estimated for the biostratigraphic boundaries. Combining all these data allows the previous calibration of SBZ during Lutetian times in the geological time scale to be refined. In particular, with this new data, we identify the SBZ 13/SBZ 14 boundary at 44.46Ma reaching C20r; a boundary interval spanning from SBZ 14 to SBZ 15 (41.36 and 42.45Ma) is found within C20n and C19n; and, finally, the top of SBZ 15 can be accurately located at 41.12Ma (C19r). [Copyright &y& Elsevier]

This study presents results of integrated larger foraminiferal biostratigraphy, lithofacies and stable carbon isotope (S13Corg) analysis carried out in the Sylhet Limestone of Dillai Parbat Limestone Mine succession, Karbi Anglong District, Assam. Larger foraminiferal assemblages assign a middle Eocene age to the studied succession of Sylhet Limestone. The Shallow Benthic Zone (SBZ) 13 and SBZ 16-18 and abarren interval in between is recognized in the studied part of the Sylhet Limestone. The SBZ 13 Zone (early Lutetian) is represented by fossiliferous limestone at the base of the section and is inferred to have been deposited in a subtidal environment. The overlying barren interval lies in the arenaceous interval and was likely deposited in a subtidal channel sand shoaling bars. The upper part of the section is marked by SBZ 16-18 (late Lutetian to Bartonian) and was deposited in subtidal channel sand inner neritic zone environments, followed by intertidal marl to subtidal limestone. The organic carbon stable isotopic data reveals a sharp negative excursion at about 34-35 m of the succession, which may be correlated with Middle Eocene Climatic Optimum (MECO) and/or vegetation types. This and earlier studies from India and elsewhere indicate that during the middle Eocene, the Neo-Tethys Sea was open and connected through the East and West coasts of India, Northeast India, western Himalaya, and most of the Middle East and southeast Europe. This vast area produced enormous amount of petroleum. [ABSTRACT FROM AUTHOR]

The upper Palaeocene shallow-water carbonates of the Qorban member (Sachun Formation) in Iran are characterised by a well-diversified larger Foraminifera and green algae assemblages. A new ornatorotaliid species, Ornatorotalia pila n. sp., is described from such deposits. The age of the new taxon is assigned to SBZ4 (late Thanetian) by the co-occurrence of Daviesina langhami, Idalina sinjarica, Lockartia retiata and Dictyokathina simplex. This new record gives further evidences on the biogeographic expansion of throughout the Neo-Tethys during the Palaeocene-early Eocene. Ornatorotaliids were shallow-water dwellers taxa that thrived in both vegetated and unvegetated bottoms. Possibly, Ornatorotalia pila n. sp. rooted in the Selandian, likely related to a possible ancestor described in open nomenclature from the Central Apennines of Italy. [ABSTRACT FROM AUTHOR]

The middle-upper Eocene Kırkgeçit Formation, the fossil content of which is the subject of this study, is deposited in a back-arc basin controlled by block-faulting. The Kırkgeçit basin is interpreted as being formed under an extensional regime related to convergence between the Anatolian plate in the north and the Arabian plate in the south. The aim of this study is to reassess the age and depositional environment of the Kırkgeçit Formation by using detailed biometric analysis data obtained from the reticulate Nummulites and determinations of other larger benthic foraminifera (LBF) in the unit. For this purpose, two sections were measured from the latest Bartonian-Priabonian aged unit. Biometric data of the Nummulites hormoensis and Nummulites fabianii from the Kırkgeçit Formation exposures in the northwest of Elazığ has been presented for the first time. In general, Nummulites fabianii has robust test with thick walls, while Nummulites hormoensis has elongated test with thinner walls in relation to the increase of water depth. The change in embryon size of these reticulate Nummulites has been considered an important indicator for evolution and biostratigraphy. Nummulites hormoensis marks latest Bartonian to early Priabonian (SBZ 18) while Nummulites fabianii is a marker for middle-late Priabonian (SBZ 19-20). The Kırkgeçit Formation in the study area was previously dated as late Lutetian-Priabonian based on LBF of it. However, by considering the LBF determined in this study, the latest Bartonian-Priabonian age was assigned to unit. Based on the paleontological and sedimentological features, the Kırkgeçit Formation has been interpreted as a unit deposited on the inner and middle parts of a shallow ramp. [ABSTRACT FROM AUTHOR]

The genus Assilina is a taxon within the Nummulitacea that appeared early in the Ypresian (Early Eocene) and continued until the end of the Lutetian (Middle Eocene). Thus, this taxon could be useful for the chronostratigraphy of this time interval. Lower Eocene rocks in southern Galala, Egypt are exposed at Bir Dakhl. This section includes marl sediments with debris flow shallow‐marine facies deposits laid down during early Eocene times and includes fossils of large foraminifera: Assilina placentula Deshayes, 1838 and Nummulites burdigalensis de la Harpe, 1926. These are systematically treated, described and illustrated. Nummulites burdigalensis belongs to the N. burdigalensis group, and Assilina placentula belongs to the group of Assilina exponens. This assumption is based on qualitative morphology and quantitative measurements. Both species, together with Operculina libyca Schwager, 1883, enable the assignment of the Bir Dakhl (D5‐40 Section) to the Early Eocene, Ypresian (SBZ10 of Serra‐ Kiel et al., 1998) supporting an earlier opinion that Assilina placentula belongs to that zone in the calibrated larger foraminiferal biostratigraphic zonation. [ABSTRACT FROM AUTHOR]

The alveolinid group of larger benthic foraminifera has been vastly studied in western and central Neo‐Tethys, but less well analysed in eastern Neo‐Tethys. In this study, 19 Ypresian (Ilerdian–Cuisian) and Early Lutetian species of Alveolina have been identified and their biometrics, taxonomy, and biostratigraphic correlation with western and central Neo‐Tethys discussed. The Taxa of Early Ypresian age (SBZ5‐9) includes Alveolina vredenburgi, A. dedolia, A. subpyrenaica, A. cf. subpyrenaica, A. moussoulensis, A. aragonensis, A. decipiens, A. cylindrata, and A. ilerdensis. The Late Ypresian age (SBZ10‐12) taxa includes A. ruetimeyeri A. oblonga, A. haymanensis, A. lehneri, A. cosinensis cosigena, A. aff. frumentiformis, A sp. aff. A. azzarolii, and A. elliptica. The Early Lutetian age (SBZ13) taxa include A. stercusmuris and A. keili. The identified species have a close affinity to those reported from other areas of the Tethyan realm. However, some of these Alveolina species are considered to have stratigraphic ranges longer than formerly reported. The first appearance of A. ilerdensis (SBZ8‐10) is recorded earlier in SBZ7. The first appearance of A. ruetimeyeri (SBZ10‐11) is recorded earlier in SBZ‐9. The study provides more evidence for understanding the evolution of the Alveolina species and their biostratigraphic distribution in the eastern Tethyan realm. [ABSTRACT FROM AUTHOR]

This investigation resulted in the biostratigraphic framework of the Upper Palaeocene–Lower Eocene rocks from the Upper Indus Basin, Pakistan, Eastern Tethys. The Patala Formation of the Chinjana Nala, Surghar Range of the Upper Indus Basin, was selected for this purpose. Lithologically, the Patala Formation is composed of shale and limestone interbeds. Three different fossil groups – smaller benthic foraminifera, planktic foraminifera, and calcareous nanno‐planktons – are used to establish a biostratigraphic framework for the Patala Formation. The biozones recognized in this study include: (a) bathyal benthic biozones, BB1 and BB2 of the Late Palaeocene and Early Eocene, respectively; (b) planktic biozones, P4 and P5 of the Late Palaeocene, while E1 and E2 of the Early Eocene; and (c) Calcareous Nanno‐planktons biozones: the NP9, which is further divided into NP9a and NP9b of the Late Palaeocene and Early Eocene, respectively. These biozones have been integrated to identify the Palaeocene–Eocene (P–E) boundary interval by applying widely used biostratigraphic criteria (i.e., Rhomboaster‐Discoaster [RD]‐assemblage of calcareous nanno‐planktons). In this study, we have considered the lithological interval between ChN/TP‐16 and ChN/TP‐17 as a marker horizon for the P–E boundary interval, which provided a basis for the correlation of locally established biozones with those established Tethys wide, that is, Pak‐DIV to part of Pak‐DVI correlated to SRX‐1 and SRX‐2, which are equivalent to BB1, P4, P5, and NP9a. Similarly, parts of the Pak‐DVI and Pak‐DVII are correlated to SRX‐3, which are equivalent to BB2, E1, E2, and NP9b within the study. [ABSTRACT FROM AUTHOR]

The upper Maastrichtian Tarbur Formation of the Zagros Zone, SW Iran, contains a rich assemblage of larger benthic Foraminifera including agglutinating, porcelaneous, and lamellar-perforate taxa. The occurrence of such a diversified foraminiferal fauna represents a prominent high diversity that took place in the Arabian platform during the latest Cretaceous. Several new species have been reported in the past decades from these carbonates, whereas many others have been described in recent times. However, the list of unknown taxa is still far from being complete. In the present contribution, we describe a new taxon referred to the miliolid genus Idalina. Idalina praecaenozoica n. sp. displays the typical basal layer that characterises the genus, whereas it differs from the other well-known Cretaceous and Paleogene allies by some morphometrical parameters. Compared to the dispersal of other Maastrichtian larger Foraminifera, the paleogeographic distribution of Cretaceous Idalina appears less extensive. Pseudonummoloculina kalantarii, another characteristic miliolid from the Tarbur Fm. is here figured with poorly known axial sections. The latest representative of the Siderolitidae, the late Maastrichtian marker taxon Canalispina iapygia is here reported as well. All such taxa give further evidence to the enhanced biogeographic radiation especially in this area before the K-Pg boundary extinction event. [ABSTRACT FROM AUTHOR]

The lower Miocene marine units of NW Iran (Hamedan–Miandoab area) were studied to establish a high-resolution biostratigraphy framework in the context of European standard biozonation (SBZ zonal scheme). The units are dominated by larger and small benthic foraminifera together with coralline algae and corals. Due to its position in the Tethyan Seaway between the Mediterranean and Indo-Pacific, the investigated area has high significance in palaeobiogeography. Seven species of benthic foraminifera were described, including Miogypsina globulina, Amphistegina bohdanowiczi, Elphidium crispum, Elphidium sp. 1, Borelis curdica, Austrotrillina asmariensis, and Peneroplis thomasi. The occurrence of Miogypsina globulina in the shallow-marine carbonates of the studied sections documents the Burdigalian SBZ 25 Zone. Austrotrillina asmariensis and Peneroplis thomasi occur with M. globulina. Simultaneously, their stratigraphical range is extended to the Burdigalian in the Middle East. Based on the discovery of lower Miocene deposits in the Hamedan–Miandoab area (previously mapped as Oligocene–Miocene units), the stratigraphy of northwest Central Iran is revised. The biostratigraphic results also present a more precise chronology for the marine transgression in the study area, initiating in the late early Miocene. The coralline algal assemblages and the abundance and diversity of larger benthic foraminifera indicate that shallow-marine Qom Formation got deposited in tropical to subtropical warm waters. [ABSTRACT FROM AUTHOR]

A site in the western flank of Jabal Ja'alan (Oman Mountains) reveals an exceptional succession across the Cretaceous–Palaeogene boundary. The sampled interval comprises a series of carbonates deposited in shallow‐water platform environments and belonging to the Murka Formation, which lies between the Simsima and Abat formations of latest Cretaceous and Thanetian age, respectively. The larger foraminifera recovered from this interval belong essentially to the group of larger rotaliids (Rotaliidae). Two new genera and two new species are here described, Praelockhartia neoakbari gen. et sp. nov. and Rotaliidium parvum gen. et sp. nov. The former shows a very characteristic architecture of an umbilicus with strong piles and two types of umbilical cavities, while the latter has characteristic dorsal supplementary chamberlets. Other species such as Rotalia cf. jacobi, Rotorbinella hensoni, Rotospirella conica and Lockhartia sp. complete the rotaliid assemblage. The entire assemblage can be considered to be of late Danian age and to belong to shallow benthic zone SBZ 2. The larger rotaliids appear to have recovered and diversified earlier than any other larger benthic foraminifera in the region after the K–Pg crisis. The rotaliids from the Murka Formation also appear to be linked to the Lockhartiinae and to play a special role in improving our understanding of subsequent diversification in the Lockhartia Sea. A new subfamily, Praelockhartiinae, is erected to accommodate all primitive forms that are architecturally close to lockhartiines. [ABSTRACT FROM AUTHOR]

The palaeobiogeography of the alveolinoid Borelis species reveals the evolutionary patterns leading to the two extant representatives, which occur in shallow‐water tropical carbonate, coral reef‐related settings. Type material and new material of fossil Borelis species, along with Recent specimens were studied to assess their taxonomic status, species circumscriptions (based on proloculus size, occurrence of Y‐shaped septula, and the index of elongation), palaeobiogeography and evolutionary dynamics. The species dealt with here are known from exclusively fossil (B. pygmaea, B. inflata, B. philippinensis, B. melo, B. curdica), and from fossil and modern (B. pulchra, B. schlumbergeri) specimens. For the first time, fossil and Recent Borelis specimens are illustrated via micro‐computed tomography scanning images. Depending on the occurrence of Y‐shaped septula, two lineages are distinguished. Deriving from the middle–upper Eocene Borelis vonderschmitti, the first lineage includes B. inflata, B. pulchra and B. pygmaea, lacking Y‐shaped septula. The first species bearing Y‐shaped septula is the Rupelian B. philippinensis of the western Indo‐Pacific. The westward migrants of B. philippinensis into the Mediterranean gave rise to B. melo (Aquitanian–Messinian) and B. curdica (Burdigalian–Tortonian). These two species became isolated from the Indo‐Pacific by the Langhian eastern closure of the Mediterranean basin and disappeared during the Messinian Salinity Crisis. Since the Tortonian, B. schlumbergeri, which descended from B. philippinensis, has inhabited the Indo‐Pacific along with B. pulchra. From the central Pacific Ocean, B. pulchra reached the Caribbean area before the early Piacenzian closure of the Central America seaway. [ABSTRACT FROM AUTHOR]

The Palaeocene–Eocene boundary (PEB) interval has been recognized in the Patala Formation, Nammal Gorge Section, Pakistan using lithostratigraphy, stable carbon isotope stratigraphy and integrated biostratigraphy. Four distinct lithological units are identified in the Patala Formation in stratigraphic order from bottom to top; unit‐1 to unit‐4. The top of unit‐3 hosts three closely spaced unconformities demarcated as U1, U2, and U3. The PEB interval is represented by a negative shift of 1.61‰ in δ13CV‐PDB representing the carbon isotopic excursion (CIE) in unit‐2. Based on the encountered foraminifera, dinocysts, and calcareous nannoplanktons, the following biozones are identified across the PEB; two larger benthonic foraminiferal (LBF) zones (SBZ4 and SBZ5), the zonal boundary slightly postdating the CIE, two smaller benthonic foraminiferal zones (BB1 and BB2), three planktonic foraminiferal zones (P4/P5 + E1), four dinocysts zones (Pak‐DV, Pak‐DVI, Pak‐DVII, Pak‐DVIII), and two calcareous nannoplankton subzones (NP9a and NP9b). The following protist, dinocyst and calcareous nannoplanktons encountered in the studied interval advocates for the placement of the possible PEB at the level between samples NAM‐SH‐07 and 08; 1—presence of the smaller benthonic foraminifera Angulogavelinella avnimelechi diagnostic of the base of the CIE and the benthonic extinction event (BEE) Tethys wide, 2—presence of the cosmopolitan and the PEB diagnostic dinocyst species 'Axiodinium augustum', 3—presence of the PEB diagnostic Rhomboaster‐Discoaster calcareous nannoplankton assemblage. The LBF species Alveolina vredenburgi [a marker species of the Larger Foraminiferal Turnover (LFT) associated with the Palaeocene Eocene Thermal Maximum (PETM) and PEB in western Tethys] occurs slightly above the onset of the CIE. Previously reported compositional change in the LBF assemblage from the Salt Range [i.e. the replacement of the Palaeocene orbitoidiform LBF (Setia and Orbitosiphon) by the Eocene LBF (Orthophragminids, Alveolina, Nummulites and Assilina)] also postdates the PEB interval here. The late appearance of Alveolina vredenburgi and the compositional change in the LBF after the onset of the CIE are attributed to the facies variation across the PEB reflecting fluctuating depositional environment due to the active tectonic across this interval. This fluctuation is evident from the smaller benthonic and planktonic foraminiferal dominating assemblages in unit‐2 representing bathyal settings followed by LBF dominating unit‐3 representing shallow carbonate platform settings. The change in LBF assemblage closely resembles the well‐known LFT associated with the PETM as well as the carbonate platform stage III and the PEB reported from other Tethyan sections. [ABSTRACT FROM AUTHOR]

The micropalaeontological inventory of the shallow-water carbonates of the Paleocene Chehel-Kaman Formation cropping out in the Kopet-Dagh Basin of north-eastern Iran is poorly known. New sampling has evidenced for the first time the occurrence of layers with abundant calcareous green algae including Dasycladales and Halimedaceae. The following dasycladalean taxa have been observed: Jodotella veslensis Morellet & Morellet, Cymopolia cf. mayaense Johnson & Kaska, Neomeris plagnensis Deloffre, Thyrsoporella-Trinocladus, Uteria aff. merienda (Elliott) and Acicularia div. sp. The studied section is devoid of larger benthic foraminifera and can be referred to the middle-upper Paleocene (SBZ 2-4) due to the presence of Rahaghia khorassanica (Rahaghi). Some of the dasycladalean taxa are herein reported for the first time not only from Iran but also the Central Neotethyan realm. [ABSTRACT FROM AUTHOR]

A systematic description of the Eocene larger foraminifera recorded in the South Pyrenean Basin (Sierras Exteriores) is presented herein. The large dataset provided in this work includes Nummulites and Alveolina species, along with a variety of other porcellaneous and hyaline taxa with lesser biostratigraphic relevance. Most of the larger foraminifera described in this work correspond to the Lutetian (SBZ13 to SBZ16 biozones) interval, but late Ypresian (SBZ11, Cuisian) and early Bartonian (SBZ17) shallow benthic zones have also been identified. A new species, Idalina osquetaensis, is described. The systematic revision of middle to late Lutetian alveolines led to a reassessment of Alveolina fusiformis and the finding of two new precursor forms, described as Alveolina aff. fragilis and Alveolina aff. elongata. The new taxa fill in the gap existing so far in the middle to late Lutetian alveolinid biostratigraphy. Despite not being exclusive to SBZ16, these forms provide realiable biostratigraphic information in facies where Nummulites are not present. This realibility lies on the correlation of Nummulites and Alveolina biostratigraphic markers in the same sections and their calibration to the global time scale through magnetostratigraphy. [ABSTRACT FROM AUTHOR]

The benthic foraminifera Pseudolituonella reicheli Marie iswidely reported from Cenomanian shallow-water carbonates of the Caribbean (Mexico) area and the Neotethyan realm. Its wall-structure is classified as imperforate, homogeneous microgranular. Specimens from the Cenomanian Sarvak Formation of southwestern Iran (Zagros Zone) yield the presence of a pseudo-keriothecal wall-structure an observation that has already been obtained from the Eocene P. robineti Gallardo Garcia and Serra-Kiel in Serra-Kiel et al. With the "reappearance" of an equivalent morphological trait and the double test size after twomainmass-extinctions (C/T andK/Pg), P. robineti might be an example of Cope's rule. Further comments on the suprageneric classification, other species of Pseudolituonella and phylogeny are provided. [ABSTRACT FROM AUTHOR]

The Gachsaran Formation from the Fars Group has a vast extent in Saudi Arabia, United Arab Emirates and Qatar (Dam Formation). It extends from the Zagros Folded Belt Zone in the south of Iran to the north of Iraq, and even to northeast Syria (Fatha Formation). In order to eliminate the ambiguities of the proposed age and cover the regional information misplacements in cases where biostratigraphy studies can be effective, surface outcrops of these deposits were investigated in three stratigraphic sections near the border of Iran and Iraq, in the area behind the mountains of the Lurestan region (Posht-e-Kuh arc). According to similar results obtained in two other sections, the age of the Gachsaran Formation in the studied region is considered to be Early Miocene (Late Burdigalian). Comparison of the results of this study with biostratigraphic studies from other parts of the Middle East, which includes 16 study areas, shows that the Gachsaran Formation in Iran and its equivalent formations (Fatha and Dam) in neighboring countries have an age range of early Miocene (Aquitanian-Burdigalian) and even Burdigalian. This age has been determined by comparing the biological contents of the Gachsaran Formation with valid official biozones, as well as the presence of the index fossil Borelis melo curdica, to cover the information gap in the area. Isotopic studies of these sections in the region show that the maximum age of these sediments is early Miocene (Burdigalian), and this confirms the results of biostratigraphic studies. [ABSTRACT FROM AUTHOR]

In the former northernNeotethys marginwhere Paleocene shallow-water limestone successions crop out (Austria, Turkey and Iran), morphotypes closely resembling Eponides have been recognized. These foraminifers are lamellar-perforated, with a trochospirally arranged set of trapezoidal chambers. We have tested their generic identification through a detailed architectural analysis of thin sections of carbonate rocks in which Eponides-like specimens have abundantly been recovered. This study shows the occurrence of bipartitor, arched septa and a pseudoumbilicus formed by the fusion of ventral ends of chambers. These features allow us to identify the specimens as Eponides, although the specific attribution has not been attempted. The evolutionary pattern displayed by the Late Cretaceous and Cenozoic Eponides and phylogenetically-related allies is briefly discussed. [ABSTRACT FROM AUTHOR]

Although the Çankırı-Çorum Basin was studied for various purposes such as geological, stratigraphical, tectonic, coal and oil exploration, studies on fossils are limited. Especially there have not been detailed studies on molluscs and larger foraminifera. The research area is located at the vicinity of Ayvalıca (north of Çankırı-Çorum basin). The Middle Eocene Kocaçay formation, which outcrops in the Çankırı-Çorum Basin, is widespread around Bayat Çorum in the north of the basin, Sulakyurt Kırıkkale in the west, Çiçekdağı Kırşehir in the south and Sungurlu Çorum in the middle of the basin. The formation is composed of conglomerate, carbonated sandstone, limestone and sandy marls and also includes rich larger foraminifera and molluscs. This study mainly focuses on taxonomy and environmental interpretations of Ostrea roncaensis (Partsch in coll. Bayan, 1870) de Gregorio, 1884, Velates perversus (Gmelin, 1791) species from Mollusca and Nummulites beaumonti d'Archiac and Haime, 1853, N. aturicus Joly and Leymerie,1848, N. perforatus (de Montfort, 1808) and Assilina exponens (Sowerby, 1840) species from larger Foraminifera. In addition, considering faunal features from bottom to top Ostrea roncaensis, Velates perversus, Nummulites aturicus and Assilina exponens Abundance Biozones were identified. The age range of the Kocaçay Formation is determined as Lutetian-Bartonian. Lithological and faunal contents indicate that sediments of the Kocaçay formation were deposited within lagoon to nummulitic sets in a shallow marine environment. [ABSTRACT FROM AUTHOR]

The Urtsadzor section, typical for the Paleocene-Eocene of Southern Armenia, is composed of hemipelagic to shelf succession. Planktonic foraminifera (PF), larger benthic foraminifera (LBF), and nannofossils were studied from Priabonian sediments of Urtsadzor section that enabled direct correlation of the biohorizons of these three groups. We present here the results of the microfossil study from the Bartonian and Priabonian parts of the section, with a special focus on larger and smaller benthic foraminifera (SBF). The 350 m thick studied interval corresponds to the planktonic foraminiferal zones P12/E10-11 to P15/E15, the nannofossil zones NP16 to NP19, the LBF zones SBZ17 to SBZ19, the SBF zones Heterolepa eocaena - Cibicidoides landjaricum, Cibicidoides truncanus, Planulina costata. The SBZ17 zone is characterized by the lowest and highest occurrences (LO and HO) of Nummulites ptukhiani and corresponds to P12 and NP16-17/CNE14-15 zones. The upper boundary of SBZ17 and that of the SBZ18A/B subzones are missing. The SBZ18C subzone, identified by the LO of Heterostegina reticulata multifida accompanied by the LOs of Pellatispira,Biplanispira, and Nummulites hormoensis, lies within P15/E14 and NP18-19 zones. The LBF is represented by 40 species of nummulitids, orthophragminids, pellatispirids, as well as Silvestriella, Fabiania, Chapmanina, and Sphaerogypsina. The SBF assemblages contain more than 50 species. The transition from SBZ18 to SBZ19 in the studied section includes the following bioevents: 1. The highest common occurrence of N. maximus, HO of D. discus, and LOs of D. pratti minor, A. alpina, and Silvestriella; 2. The lowermost rare occurrence of Spiroclypeus, LO of H. reticulata mossanensis; 3. The lowermost common occurrence of N. fabianii and Spiroclypeus. The Bartonian-Priabonian boundary in this section, defined by the LO of Chiasmolithus oamaruensis, falls to the lower part of P14 and E14 zones, Cibicidoides truncanus zone of SBF, and between SBZ17 and 18C zones of LBF. [ABSTRACT FROM AUTHOR]

Soritids are a successful group of larger Foraminifera with several extant representatives that display a complex alternation of generations, the so-called paratrimorphic life cycle. Fossil soritids are abundantly widespread through the geological record starting from the Albian. The oldest Soritidae possessing annular chambers and cross-wise oblique chamber communications is represented by the Paleocene species Mardinella daviesi. The present paper provides a description of the morphology and anatomy of the three reproductive generations recovered in a Mardinella-rich assemblage from a lower Paleogene shallow-water carbonate succession in SW Iran (Zagros Zone). Comparison among proportion of schizonts vs. gamonts with extant soritids shows that there is an easy match. This would confirm that the paratrimorphic life cycle was successfully adopted by the early soritids to maintain fitness with the environment and to keep a stable mutual relationship with a certain group of endosymbionts. [ABSTRACT FROM AUTHOR]

The micropalaeontology of the mid-Cretaceous Derdere Formation (Mardin Group) from outcrops close to the town of Derik in south-eastern Turkey is described here. In thin sections from the carbonates that form the majority of this formation, rich and diverse micropalaeontological assemblages are present. These include larger benthonic foraminifera, planktonic foraminifera, and other microfossils, including calcareous algae. Alveolinid foraminifera are particularly common and include a new species – Simplalveolina mardinensis. In contrast to some previous studies, the majority of the section can be demonstrated to be Cenomanian (notably middle Cenomanian) in age with no confirmation of extension into the Albian or Turonian. Deposition took place on a carbonate ramp within a range of discrete deposition settings ranging from peritidal to outer ramp. A notable feature is the small-scale (a few metres) shallowing-up cycles within the inner-ramp facies that may be allocyclic or autocyclic in origin. Three major deepening events are recognised within the succession, characterised by more open marine microfauna and microfacies. These occur at the base of the formation, within the mid-Cenomanian lower part, and towards the top of the formation. These may correlate with three Cenomanian deepening phases seen in other parts of the Arabian Plate. [ABSTRACT FROM AUTHOR]

A systematic description of the Eocene larger foraminifera recorded in the South Pyrenean Basin (Sierras Exteriores) is presented herein. The large dataset provided in this work includes Nummulites and Alveolina species, along with a variety of other porcellaneous and hyaline taxa with lesser biostratigraphic relevance. Most of the larger foraminifera described in this work correspond to the Lutetian (SBZ13 to SBZ16 biozones) interval, but late Ypresian (SBZ11, Cuisian) and early Bartonian (SBZ17) shallow benthic zones have also been identified. A new species, Idalina osquetaensis, is described. The systematic revision of middle to late Lutetian alveolines led to a reassessment of Alveolina fusiformis and the finding of two new precursor forms, described as Alveolina aff. fragilis and Alveolina aff. elongata. The new taxa fill in the gap existing so far in the middle to late Lutetian alveolinid biostratigraphy. Despite not being exclusive to SBZ16, these forms provide realiable biostratigraphic information in facies where Nummulites are not present. This realibility lies on the correlation of Nummulites and Alveolina biostratigraphic markers in the same sections and their calibration to the global time scale through magnetostratigraphy. [ABSTRACT FROM AUTHOR]