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In the present-day Indo-Pacific coral-reef settings two genera of alveolinoidean porcelaneous larger benthic foraminifera (LBF) occur, namely Alveolinella and Borelis. Alveolinella is represented by a single species, A. quoyi , whose northernmost record is in Okinawa-jima (central Ryukyu Islands, Japan). Although the Indo-Pacific area, and especially the Coral Triangle, is a biodiversity hotspot since the Early Miocene, in-depth investigation on fossil representatives of present-day LBF is limited to a few taxa. To help bridge this knowledge gap, the palaeobiogeographical dynamics of A. quoyi is assessed. Analysis of data from the palaeontological literature shows that its first appearance datum is from the Tortonian (Late Miocene) of East Kalimantan and Papua New Guinea. In the Pliocene–Pleistocene the Indonesian Throughflow constrained the species within the Central Indo-Pacific. Finally, during the Late Pliocene the northward migrants arrived in the shallow-water carbonate settings of Okinawa-jima where the species is still thriving. [ABSTRACT FROM AUTHOR]

We investigate the Palaeocene succession of the Hazara Basin (Northern Pakistan) to better understand the impact of climate change on marine carbonate-producing organisms. These shallow-water carbonates, deposited during the Late Palaeocene, before the onset of the Palaeocene-Eocene Thermal Maximum, were studied using a quantitative approach to highlight changes in the skeletal assemblage. We recognise a decrease in the abundance of colonial corals and green calcareous algae and an increase in larger benthic foraminifera and red calcareous algae from the early Thanetian to the late Thanetian. Increasing temperatures may represent a plausible cause for the decline of the more sensitive colonial corals in favor of the more tolerant larger benthic foraminifera. A similar pattern is observed in most successions deposited along the margins of the Neotethys Ocean, suggesting a connection with the Late Palaeocene environmental changes that heralded the PETM hyperthermal event. Our stratigraphic analysis of the Hazara Basin strata suggests that the biotic turnovers occurred during the Palaeocene – Eocene transition started already before the onset of the Palaeocene Eocene Thermal Maximum as recorded by the geochemical proxies.

Two stratigraphic sections are investigated, and a diverse larger benthic foraminiferal assemblage is recorded from the upper Paleocene–lower Eocene Southern Galala Formation at the Galala Plateaus, north Eastern Desert, Egypt. Twenty-eight larger foraminiferal species, belonging to thirteen genera, are identified and their comparative stratigraphic range with the Tethyan zonations of Hottinger (1960) and Serra-Kiel et al. (1998) is documented. Nine shallow benthic zones (SBZ3-6 and SBZ8-12) are designated in the studied interval, involving index zonal markers, e.g., Glomalveolina primaeva (Reichel), G. levis Hottinger, Nummulites atacicus (Leymerie), Alveolina vredenburgi Davies, and A. ellipsoidalis Schwager. Fifty-four thin sections are prepared and analyzed, yielding seven microfacies types in the present study, with larger benthic foraminifera as the dominant biotic components. These microfacies types indicate a deposition in restricted tidal flat inner ramp to open-marine middle ramp environments. The inner ramp environments are dominated by alveolinids, orbitolitids, and in part by miliolids and orthophragminids, reflecting euphotic to mesophotic, meso-oligotrophic, and normal to hyper salinity conditions. The middle ramp environment is characterized by nummulitids, implying meso-oligophotic, oligotrophic, and normal salinity conditions. The studied successions at the Galala Plateaus are devoid of corals in platform stages II and III, similar to the Pyrenean strata from middle latitudes at the northern Tethys, except for small coral patches in both stages in the latter due to the cooler temperature. The Early Eocene (Cuisian) Nummulites accumulations suggest a development on paleohighs in a distal inner ramp environment, and then a transportation by wave and current actions into the surrounding proximal middle ramp environment. [ABSTRACT FROM AUTHOR]

Three key Paleocene deep-sea sections cropping out in northern Italy contain intercalations of calciturbiditic, larger foraminifera-bearing beds derived from shallow water environments. The reconstructed Southern Alps record obtained by splicing the three sections allowed a direct correlation of the shallow benthic SB and calcareous nannofossils CN Zones, leading new data about the Shallow Benthic biozonation for the Danian-Thanetian interval and proposing four new SBP (Shallow Benthic Paleocene) Zones (SBP1-4). Such revision relies on an innovative biostratigraphic approach based on larger foraminiferal biohorizons instead of marker species according to the traditional approach used since the introduction of the SB Zones. Based on our study, the SBP1/SBP2 boundary turns out to be about 2 Ma after the K/Pg crisis, highlighting a quite fast recovery of the complexity among foraminifera. [ABSTRACT FROM AUTHOR]

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The Cenozoic larger foraminifera are important for biostratigraphy in SE Asia. This review examines the taxonomic inconsistencies of this group and especially the confusion over concepts of evolution, migration, radiation and extinction. It is proposed that from the Mediterranean to Indo-Pacific, Latest Eocene through Miocene, larger foraminifera populations were more homogenous than previously believed. Lineages show a slow morphological radiation interrupted by several extinctions. This pattern is superimposed on a long-term decline in larger foraminiferal abundance. The dating of the major biostratigraphic events are qualified. The main lineages of larger foraminifera can be classified by their evolutionary style. The classically "large" genera have highly peramorphic trends achieved through strong orthoselection, and these lineages were the most severely hit by a series of Mid-Eocene to Mid-Miocene extinction events. Other carbonate facies taxa that are traditionally grouped with the larger foraminifera are characterised by weak paramorphism, and these were much less affected by the extinction events. Some of these weakly peramorphic forms underwent Latest Miocene to recent radiation to and locally become rock-forming organisms. The three major and one minor larger foraminiferal extinction events since the Mid Eocene coincide with abrupt tectonic events across SE Asia. However, there are probably multiple causes for these extinctions, including global climatic changes. [ABSTRACT FROM AUTHOR]

Microbiostratigraphy and paleoecology of the Bajwan Formation (Chattian) from the Kirkuk Oil Field (K. 160), Kirkuk area, Northeastern Iraq, are investigated. Thirty-one species from 17 genera of large benthic foraminifera in addition to non-foraminifera fossils such as Gastropods, Bivalves, and Echinoid fragments, Bryozoan, Coral, and Algae are recognized from the studied well. Based on the recognized large benthic foraminifera, it is subdivided into two biozones: Praerhapydionina delicate–Peneroplis evolutus Assemblage zone and Praerhapydionina delicate–Archaias kirkukensis Assemblage zone. Both suggest Late Oligocene (Chattian) age. The recognized biozones were correlated with comparatively well-known biozones from other parts of the Tethys region which showed a good comparison between the biostratigraphic zones established in this study with other studies. The biotic associations identified in this study suggest that this association thrived in tropical-to-subtropical environments, generally found in a restricted to shallower water depth, with normal water salinity environment ranges from 34 to 50‰, under mesotrophic-to-oligotrophic conditions. [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]

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, Elazigin 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.).

We document the stratigraphy, lithofacies and depositional environment of the lower Eocene-lower Oligocene Nisai Group, based on petrographic and micropaleontological analysis, and field observations. We rename the whole sedimentary succession as the Nisai Group and divide it into three formations, from bottom to top; Jabrai, Torkhezhe Tsah and Nisai formations. The Jabrai Formation comprises a thick succession of olive gray mudstone and shales with subordinate sandstone, limestone and quartzose conglomerate, interpreted as deltaic and littoral deposits. The Torkhezhe Tsah Formation comprises calciturbidites in its lower part and periplatform oozes and basinal shales in upper part. The shallow-marine carbonate material of calciturbidites possibly derived from a lost platform which was a narrow delta-top-platform developed over deltaic sediments of the Jabrai Formation. The uppermost unit, the Nisai Formation, comprises thick bedded limestone with subordinate shale and nodular reefoid limestone, and shows a shallowing-up succession overlying the slope and basinal deposits of the Torkhezhe Tsah Formation. The presence of Cr-rich spinels in sandstone of the Jabrai Formation, ultramafic-mafic and quartzite lithoclasts in calciturbidite beds as well as paleocurrent data, suggest that siliciclastic sediments of the Nisai Group derived from the Zhob Valley Ophiolites. Moreover, the presence of quartz, igneous and metamorphic extraclasts, and dolomitic horizons within calciturbidite beds, indicate deposition of these calciturbidites in response to lowering of sea level. We propose that emplacement of Zhob Valley Ophiolites served as a drainage divide and supplied deltaic sediments to the Jabrai Formation to its north and the Ghazij Group to the south. [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.

Bioerosion is rare in large benthic foraminifera (LBF) in the Eocene of Ziarat Formation, Iran. Three bioerosion ichnotaxa have been identified, including more common Trypanites isp. and Entobia isp., and rare Meandropolydora sulcans. The rare bioerosional traces in LBF tests support the scenario of an oligotrophic nutrient regime during the studied interval. The sedimentation rate may have also been among the controls on the bioerosion of LBF in the Middle Eocene of Iran, but the oligotrophic nutrient regime likely had a stronger effect. The bioerosion of LBF tests during the Middle Eocene Climatic Optimum (MECO) was rather low or at maximum moderate, suggesting that an oligotrophic nutrient regime could compensate for the increase in bioerosion caused by ocean acidification and warming. • Bioerosion is rare in LBF from MECO interval of Ziarat Formation. • Rare bioerosional traces in LBF suggest an oligotrophic nutrient regime. • MECO did not caused increase in bioerosion rates. • Bioerosion at oligotrophic sites is not affected by the ocean acidification and warming. [ABSTRACT FROM AUTHOR]

The Eocene Jahrum Formation in High Zagros was studied in Kuh-e- Soukhteh and North Gahrou sections (southwest of Shahrekord region, Chahar-mahal Bakhtiari Province). This formation, composed of limestone, marl, and dolomitic limestone (dolostone), accumulated on a marine platform within the Neo-Tethys ocean realm. It yields a rich foraminiferal fauna, in which three larger benthic foraminiferal assemblage zones were identified. Two assemblage zones in the North Gahrou section were correlated to the Ypresian and Bartonian, and one assemblage zone is represented in the Kuh-e- Soukhteh section and assigned to the Bartonian. In addition, three other groups of benthic foraminiferal associations have been identified based on test wall type (porcellaneous, agglutinate, hyaline) and paleogeographical significance. A discontinuity marked by a hiatus from Cuisian to Lutetian in the North Gahrou section was most probably due to a concealed fault. According to microscopic textures and distribution of benthic foraminifera and other components (peloids, intraclasts, etc.), a gentle depth gradient from the inner ramp to the proximal outer ramp may be reconstructed.

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]

A taxonomic study of the larger foraminifera found in Paleocene rocks 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 shallow platform stratigraphic sections, representative from coastal to platform margin depositional settings. The results from two base of slope sections with numerous intercalations of calcareous turbidites with 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, global reference section for the Danian-Selandian and Selandian-Thanertian GSSPs. The new calibration of the Paleocene SBZs is summarized as follows. The SBZ 1 is constrained to the first 1.09 m.y. of the Paleocene; this first Paleogene biozone lacks distinct larger foraminifera biomarkers and thus is defined by an association of non-exclusive taxa composed of Valvulineria patalaensis, Stomatorbina? binkhorsti, P.? antiqua and Bangiana hanseni. The SBZ 2 now appears as the biozone encompassing most of the Danian stage (from ca. 64.91 m.y. to 61.6 m.y.), and is characterized by the association of Haymanella elongata, Haymanella paleocenica, Kayseriella decastroi, Rotospirella conica, Pyrenerotalia depressa, Elazigina dienii and Paralockhartia eos. The SBZ 2-SBZ 3 boundary coincides with the base of the Selandian stage (ca. 61.6 m.y.). The SBZ 3 biozone is defined by Glomalveolina primaeva, Periloculina slovenica, Vania anatolica, Coskinon rajkae, Fallotella alavensis, Cribrobulimina carniolica, Miscellanea yvettae, Miscellanea juliettae, Miscellanites primitivus, Miscellanites minutus, Ranikothalia soldadensis, Nummulites heberti and Discocyclina seunesi. The SBZ 3-SBZ 4 boundary is now ascribed to ca. 57.2 m.y. 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. 56.0 m.y.).

Sea surface temperatures (SST) have been identified as a main controlling factor on larger benthic foraminifera (LBF) living in tropical to sub-tropical shallow-water carbonate and mixed siliciclastic‑carbonate platforms. Changes in SST, along with those in ocean acidification and nutrient content recorded in the global oceans throughout their history will not only continue but also be amplified in the future at an unprecedented rate of change possibly reaching levels found in the geological record. This study focuses on the Oligocene (mean SST 8 °C higher than present) and the Miocene (SST 5–8 °C higher than present) epochs which were characterized by a higher richness in porcelaneous LBF (pLBF) than today. A systematic re-assessment and comprehensive literature survey of stratigraphic ranges and palaeogeographic distribution in the Western Tethyan (Mediterranean) and Indo-Pacific regions are used to evaluate the impact of changes in SST, seawater p CO 2 and pH on the biodiversity of the Oligocene–Miocene pLBF Alveolinella , Austrotrillina , Borelis , Bullalveolina , Flosculinella, and Praebullalveolina. Two peaks in species richness were identified during the Aquitanian and Langhian–Serravallian. These peaks occurred when SST was ∼29 °C, with p CO 2 of ∼400 ppm and pH > 7.8. These values are comparable to those of today. The minima in species richness recorded in the Rupelian–early Chattian, in the Burdigalian and from the Tortonian onward can be correlated to the detrimental effects of both minimum (< 26 °C) and maximum (> 31 °C) SST thresholds. High p CO 2 (> 600 ppm) values, which are limited to the Rupelian–early Chattian, are also detrimental to species richness. Seawater pH higher than 7.7 did not negatively affect species richness. These historical trends have serious implications for the future diversity of pLBFs with the increasing likely scenario of rising SST and p CO 2 and lowering of pH values in the near future. These developments can potentially lead to diversity decrease and even extinction of pLBFs. However, the resilience of present-day pLBF species to rising SST and p CO 2 levels is underpinned by the evolutionary histories of their fossil counterparts during climate variations, albeit at much different rates of change. • The Aquitanian and Langhian–Serravallian peaks in richness occurred when SST c. 29 °C. • Detrimental effects of high p CO 2 (> 600 ppm) in the Rupelian–early Chattian. • Detrimental effects of high tropical SST (> 31 °C) during the beginning of MCO. • Detrimental effects of low tropical SST (< 26 °C) in the Tortonian. • Sea-level highstands affected diversification of Oligocene–Miocene pLBF. [ABSTRACT FROM AUTHOR]

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]

Specimens displaying unusual ("abnormal" or aberrant) test morphologies, for example, the presence of twin embryos, or test repair after damage, are reported from Lower Cretaceous Orbitolinidae. Twin embryos (which have not always been recognized as such in the literature) are described from the upper Barremian of Tibet and France (Palorbitolina lenticularis), the upper Albian of Somalia (Orbitolina gr. sefini), and the upper Aptian-early Albian of Texas (e.g., Mesorbitolina texana). Twin embryos have so far only been reported from the Orbitolininae (with complex embryo), and not from the Dictyoconinae (with simple embryo). Repaired partially damaged tests (the damage possibly caused by predation or mechanical fracture) are observed in lower Aptian orbitolinids from Iran. Regeneration after damage (bioadjustment) leads to malformed tests. [ABSTRACT FROM AUTHOR]

The effects of human activities on the earth’s environment have gained increasing attention in recent years. With coral reefs declining worldwide, efficient tools for assessing reef health are more important than ever. The species of larger foraminifera known as Peneroplis pertusus share key characteristics with reef building corals. By examining the populations’ natural distribution along with the abiotic factors affecting bleaching, a better understanding of reef systems as a whole is achieved. In this study, P. pertusus was collected from ten different sites on a fringing reef in Moorea, French Polynesia. Collected from coral rubble at one, two, and three meters depths, they were analyzed for abundance, size, and extent of bleaching. Light experiments were used in the laboratory to determine response to increased solar radiation. One-way statistical analysis, along with the Wilcoxon test found no strong correlation between depth and percent bleaching. A difference between individual size and percent bleaching was found and a natural population dynamics are presumed to occur n Moorea. Light experiments found increased bleaching in P. pertusus showing increased solar radiation to be a factor in bleaching.

Abstract This study aims to record the Middle Eocene larger benthic foraminifera from an outcrop exposed in the Cairo–Suez district, Egypt, and to discuss their geographic distribution along the southern Tethys. This succession is subdivided, from base to top, into the Observatory and Qurn formations. The recorded foraminiferal assemblage includes Dictyoconus aegyptiensis , Rhabdorites malatyaensis , R. minima , Idalina cuvillieri and Pseudolacazina schwagerinoides. Due to the absence of Nummulites species, two local larger benthic foraminiferal biozones are established Dictyoconus aegyptiensis and Idalina cuvillieri - Pseudolacazina schwagerinoides. In terms of paleobiogeography, a great similarity is noticed between the Egyptian foraminiferal assemblage and those of Libya, Oman, Iran and Turkey. Consequently, this indication supports foraminiferal migration along the southern Tethys. Highlights • Middle Eocene larger benthic foraminifera from Egypt. • Biostratigraphic zonations based on foraminifera. • The foraminiferal assemblages are similar to those from the North Africa and the Middle East. [ABSTRACT FROM AUTHOR]

Megalospheric specimens of Nummulitidae from eight localities in western and central Cuba were morphometrically investigated using test characters described by 11 growth-independent and growth-invariant attributes that provide a complete geometric reconstruction of nummulitid equatorial morphology. The species Nummulites striatoreticulatus, Palaeonummulites trinitatensis, Operculinoides floridensis and O. soldadensis were classified by an agglomerative cluster analysis. Discriminant analysis yielded significant morphological separators between the species such as the backbend angle, marginal radius increase, perimeter ratio and first chamber length. The transition of tightness to laxity of the spiral was an important morphological separator at the generic level, representing a clear general trend coupled with the change in palaeodepth. Based on further discriminant analysis, an increase in proloculus size was detected in Nummulites striatoreticulatus from the middle Eocene to early late Eocene, supporting this important evolutionary pattern in many lineages of Nummulites. Operculinid forms showed an opposite and more weakly pronounced time-dependent trend in the size decrease of the proloculus. In the Cuban localities, Nummulites striatoreticulatus occurs from the Lutetian to Priabonian, while Palaeonummulites trinitatensis is restricted to the Bartonian to Priabonian. The moderately to loosely coiled operculinid taxa O. floridensis and O. soldadensis have longer stratigraphical ranges from the middle Eocene to probably the early Oligocene. Operculinoides floridensis and O. soldadensis show a broader variability in marginal radius increase, and thus probably occupied wider niches than N. striatoreticulatus. The latter seems to be restricted to the shelf edge and to the shallowest parts of the upper slope. A possible phylogenetic connection between Heterostegina and Operculinoides is suggested by the closest equatorial morphology of Heterostegina sp. indet. to tightly coiled forms of Operculinoides floridensis. Discriminant analysis documents the strongest similarities in perimeter ratio, backbend angle, initial marginal radius and proloculus mean diameter. [ABSTRACT FROM AUTHOR]

Abstract The shell architecture of Fissoelphidium operculferum Smout from the Tarbur Formation, Maastrichtian of Zagros, has been re-studied. Based on the characters of the canal system geometry and that of folia, Fissoelphidium became comparable with the Maastrichtian-Paleocene genus Laffitteina Marie. A radial network of infolded folia builds the umbilical ornamentation of Fissoelphidium. After these thoughts, the suprageneric position of F. operculiferum is out from the family Miscellaneidae and considered under Cuvillierinidae (subfamily Laffitteininae). The associated lamellar perforate benthic Foraminifera, including rotaloideans, from the studied Tarbur Formation outcrops are here illustrated and commented. Although most of them remain under open nomenclature, they could be critical to characterize the dispersal of fauna between the Mediterranean Tethys and the Middle East domain, evidencing their paleobiogeographic as well as the possible biostratigraphic importance. [ABSTRACT FROM AUTHOR]

The Oligocene–Miocene carbonate record of the Zagros Mountains, known as the Asmari Formation, constitutes an important hydrocarbon reservoir in southern Iran. This marine carbonate succession, which developed under tropical conditions, is explored in terms of larger foraminiferal biostratigraphy, facies analysis and sequence stratigraphy in a new section at Papoon cropping out in the western Fars sub‐basin, in the south‐east of the Zagros belt. Facies analysis shows evidence of re‐working and transport of skeletal components throughout the depositional system, interpreted here as a carbonate ramp. The foraminifera‐based biozones identified include the Globigerina–Turborotalia cerroazulensis–Hantkenina Zone and Nummulites vascus–Nummulites fichteli Zone, both of Rupelian age, the Archaias asmaricus–Archaias hensoni–Miogypsinoides complanatus Zone of Chattian age and the 'Indeterminate' Zone of Aquitanian age. The vertical sedimentary evolution of the formation exhibits a progressive shallowing of the facies belts and thus the succession is interpreted as a high‐rank low‐order regressive systems tract. This long‐lasting Rupelian–Aquitanian regressive event is in accordance with accepted global long‐term eustatic curves. Accordingly, long‐term eustatic trends would have been a factor controlling accommodation during the deposition of the Asmari Formation studied in the western Fars sub‐basin. [ABSTRACT FROM AUTHOR]

I report the first observation of the symbiotic relationship between a serpulid polychaete and a larger foraminifer, Discocyclina, from the Eocene of the Ebro Basin (NE Spain). Discocyclina tests are the larger and most abundant element of the fossil assemblage in a limestone bed within a fan delta series, and seems to be a preferred substrate by the serpulid larvae to settle. The bioimmuration of the serpulid tube within the foraminiferal test shows that the polychaetes attached and grew on living foraminifers, which continued growing after the serpulid’s death. The foraminifer could benefit from the filtering activity of the serpulid, although in some cases the serpulid attachment caused an anomalous growth of the foraminiferal test. Some foraminifer individuals survived to two, possibly three successive episodes of serpulid attachment, which suggests a life span of 1-3 years for this Discocyclina species, similar to that of recent hyaline larger foraminifers such as Amphistegina or Paleonummulites. This sheds new light on the paleobiology of this type of larger foraminifers without recent counterparts that thrieved during Late Cretaceous and Paleogene times. [ABSTRACT FROM AUTHOR]

The Early Paleogene Tethyan domain saw the development of large platform carbonates rich in large benthic foraminifera (LBF), of which the Taleh Zang Formation in Lurestan Basin, SW Iran, represents an excellent example. The LBF assemblage is dominated by alveolinids, together with a variety of foraminiferal genera such as Nummulites , Rotalia , Sackesaria , Assilina , Operculina , and Glomalveolina. Smaller benthic foraminifera, calcareous algae, gastropods, echinoids, and bivalves constitute minor components of the carbonate. Biostratigraphy analysis of the LBF is conducted on two distinct sections of the Taleh Zang Fm. The sections referred to as TZ-1 and TZ-2 have respective thicknesses of 87 m and 132 m. This analysis has constrained the formation age to the early Ypresian within Shallow Benthic Zones (SBZs) 5–7. Facies analysis supports the major accumulation of these successions in a shallow water environment within the euphotic zone. We recognize 9 distinct facies and microfacies representing four main depositional environments including tidal flat, lagoon, bioclastic shoal, and shallow open marine. These environments are distributed along a low-angle homoclinal ramp and form the foundation of a stratigraphic interpretation characterized by intervals displaying shallowing and deepening trends. Three shallowing-upward intervals have been identified within the Taleh Zang succession. The determined intervals cannot be solely attributed to global sea level fluctuations and support a significant impact of the regional structural context resulting from collision-induced uplift and variable subsidence rates. The identified intervals exhibit local and regional correlation and compatibility on the Arabian Plate, providing robust confirmation of the significant roles played by both tectonics and eustasy at a regional scale. • Taleh Zang Fm. highlights a rich LBF assemblage, shedding light on the early Eocene central Tethyan domain. • Four main carbonate depositional settings on a low angle homoclinal ramp system. • Three deepening-shallowing intervals linked to local and regional tectonic activities and global sea level changes. • Enhance understanding of LBF evolution and biodiversity patterns in the central Tethyan and Arabian Peninsula hotspots. [ABSTRACT FROM AUTHOR]

Six stratigraphic sections were investigated from the middle Eocene to middle Miocene carbonate deposits along the Tobruk-Al Bardia scarps of northeastern Cyrenaica, NE Libya. The studied sequence comprises five rock units; the Darnah, Al Bayda, Al Abraq, Al Faidiyah, and Al Jaghbub formations. Eleven carbonate facies were distinguished at outcrop-scale and several microfacies were recognized and the outcome indicates a shelf-carbonate platform complex. The palaeohabitat of larger benthic foraminifera and associated biota in the studied sequence has been interpreted by comparison with its present-day counterpart. Nine shallow benthic foraminiferal biozones are recognized based on first and last occurrences of diagnostic larger benthic foraminifera. The late middle Eocene Darnah Formation contains a nummulitic assemblage with variable species, including the Nummulites gizehensis/Nummulites lyelli group, which represents SBZ17-SBZ18 in the Bartonian. The recovery of Nummulites vascus and Nummulites fichteli and associated taxa ascribes the overlying deposits of the Al Bayda Formation to the early Oligocene (early Rupelian) larger foraminiferal zone SBZ21. The total nummulitid assemblage of the overlying Al Abraq Formation is early Oligocene (late Rupelian) in age which corresponds to larger benthic foraminiferal zone SBZ22. The base of the zone correlates with the base of the Al Abraq Formation and is defined by the first appearance of Operculina complanata and Eulepidina cf. dilatata. The top of the zone is present in the lower part of the Al Faidiyah Formation (early Chattian) and is marked by the first appearance of Miogypsinoides complanatus. The middle part of the formation corresponds to larger foraminiferal zone SBZ23 (late Chattian). The base of this zone is marked by Miogypsinoides complanatus whereas the top of the zone is marked by last occurrence of Eulepidina cf. dilatata and Nephrolepidina sp. and the first appearance of Nephrolepidina aff. tournoueri. The upper stratigraphic levels of the Al Faidiyah Formation correspond to larger foraminiferal zone SBZ24 in the lower Miocene (Aquitanian). The base of the zone is marked by the first occurrence of Nephrolepidina aff. tournoueri and the upper zone boundary is represented by the last occurrence of the latter taxa and the first appearance of Miogypsina globulina. The last two larger benthic foraminifera zones which have been recognized in the deposits of the overlying Al Jaghbub Formation represent zones SBZ25 in the Burdigalian (early Miocene) and SBZ26 in the Langhian and Serravallian (middle Miocene). The base of zone SBZ25 is marked by the last occurrences of Miogypsinoides complanatus and Nephrolepidina aff. tournoueri and the first appearance of Miogypsina globulina. The top of SBZ25 and the base of the upper SBZ26, however, is marked by the last occurrence of the latter taxa and the first appearance of Borelis melo melo. [ABSTRACT FROM AUTHOR]

The lower Oligocene hyaline and porcellaneous larger foraminifera of a carbonate platform setting, north of Sonqor, were studied for high-resolution biostratigraphy in the context of European standard zonation (Shallow Benthic Zones). According to the geological map of Kermanshah, these beds were previously ascribed to the Miocene. The identified larger foraminifera include Nummulites fichteli Michelotti, Nummulites vascus Joly & Leymerie, Operculina complanata (Defrance), Asterigerina rotula (Kaufmann), Planorbulina bronnimanni Bignot & Decrouez, Discogypsina discus (Goës), Gypsina mastelensis Bursch, Halkyardia maxima Cimerman, Stomatorbina concentrica (Parker & Jones), Praerhapydionina delicata Henson, Penarchaias glynnjonesi (Henson), Austrotrillina aff. paucialveolata Grimsdale, and Haddonia heissigi Hagn, associated with the coralline alga Subterraniphyllum thomasii Elliott. The foraminiferal association characterises the SBZ 21 Zone (early Rupelian). [ABSTRACT FROM AUTHOR]

The systematics and phylogenetic relations of the Oligocene species of Heterostegina (Nummulitidae) are poorly known compared to those of Eocene and Miocene species. The new species Heterostegina matteuccii sp. nov., characterized by the combination of an advanced nepionic stage (i.e. very few operculine chambers) and a relatively small proloculus, is here described from the lower Oligocene Caltavuturo Formation of Portella Colla (Madonie Mts, Sicily, Italy). The same species is recorded also in the 'Calcaire àa astéeries' Formation of Illats (Northern Aquitaine, near Bordeaux, France). Biometrically, H. matteuccii sp. nov. does not fit within any known Neo-Tethyan lineage of Heterostegina from the Eocene to the Miocene, and hence is considered to be a member of a distinct phyletic lineage. The advanced nepionic stage of H. matteuccii sp. nov., however, calls for the existence of predecessors. The Priabonian (and possibly also earliest Oligocene) H. ocalana Cushman, 1921 from the American-Caribbean realm is here interpreted as the most probable ancestral form for the H. matteuccii lineage. Thus, an early Oligocene eastward transatlantic migration of this lineage may be inferred. New results of strontium isotope stratigraphy from both sides of the Atlantic Ocean are consistent with this hypothesis. [ABSTRACT FROM AUTHOR]

The Lower OligoceneAsmari Formation occupies thewestern and eastern flanks of the JabalHafit anticline and thewestern limb of the Jabal Malaqet-Mundassah anticline in the southeast of the United Arab Emirates near the Oman border. In this area the Asmari Formation unconformably overlies the Upper Eocene Dammam Formation. In this study an Early Oligocene characteristic assemblage of calcareous nannofossils, foraminifera, corals, calcareous algae, bryozoa, mollusks and echinoids is described from the carbonate rocks of the Asmari Formation. The Asmari stratigraphic succession is dated by analysis of the calcareous nannofossil assemblages and planktonic and larger foraminifera. The results of this study indicate that the succession fallswithin the EarlyOligocene Zones NP24 and P20-P21. About seventeen nannofossil species are documented for the first time in this formation, along with three planktonic and larger foraminiferal species. The Oligocene rocks in the study area provide results consistent with a shallow-water inner shelf within the photic zone. [ABSTRACT FROM AUTHOR]

We investigated the symbiont-bearing benthic foraminifer Palaeonummulites venosus to determine the chamber building rate (CBR), test diameter increase rate (DIR), reproduction time and longevity using the 'natural laboratory' approach. This is based on the decomposition of monthly obtained frequency distributions of chamber number and test diameter into normally distributed components. Test measurements were taken using MicroCT. The shift of the mean and standard deviation of component parameters during the 15-month investigation period was used to calculate Michaelis-Menten functions applied to estimate the averaged CBR and DIR under natural conditions. The individual dates of birth were estimated using the inverse averaged CBR and the inverse DIR fitted by the individual chamber number or the individual test diameter at the sampling date. Distributions of frequencies and densities (i.e., frequency divided by sediment weight) based on both CBR and DIR revealed continuous reproduction throughout the year with two peaks, a stronger one in June determined as the onset of the summer generation (generation 1) and a weaker one in November determined as the onset of the winter generation (generation 2). This reproduction scheme explains the presence of small and large specimens in the same sample. Longevity, calculated as the maximum difference in days between the individual's birth date and the sampling date, is approximately 1.5 yr, an estimation obtained by using both CBR and DIR. [ABSTRACT FROM AUTHOR]

A new larger benthic foraminifer, Asterigerina cayrazensis n. sp., is described from the upper Ypresian (middle-upper Cuisian) of the Çayraz section, N of Haymana, S Ankara, central Turkey, from which also the rotaliine species Ornatorotalia spinosa, O. granum and Granorotalia sublobata are first recorded. In addition, Ornatorotalia sp. is recorded from the Thanetian limestone of the Harabekayış section, W Elazığ, eastern Turkey.

The Oppelzone remains a controversial topic in stratigraphy, despite the attempts to systematize biozonal units in the International Stratigraphic Guide ( ISG). In the first edition of the ISG, the Oppelzone was regarded as a particular kind of biozone, although its boundaries were recognized as 'difficult to define empirically'. This is probably the main reason why the Oppelzone was removed from the second edition of the ISG. Here, we review briefly the history and significance of the Oppelzone, starting from Jurassic zonal biostratigraphy as introduced by Oppel himself, and based mainly on ammonites, to its present usage, distinguishing the multiple meanings of the unit - biostratigraphical, chronostratigraphical, or even as a time interval. We review the Oppelzone as integral part of the current biostratigraphy of Palaeogene-Miocene larger foraminifera (the Shallow Benthic Zones, SBZ). Here, different species concepts in individual systematic groups result either in Oppelian (e.g. nummulitids, alveolinids) or non-Oppelian (e.g. lepidocyclinids, miogypsinids and in part orthophragmines) biozones. In addition, various regional larger foraminiferal zonations have been established. These different kinds of biozones are subsumed under the biochronostratigraphical SBZ system in a similar way as regional ammonite zonations are integrated in the standard ammonite zonation. To overcome issues of fuzzy-defined boundaries, a novel research programme is needed to: (1) establish the most suitable markers for biozonal boundaries; (2) enhance correlation with different systematic groups (especially planktonic foraminifera and calcareous nannofossils) and with other stratigraphical tools (magnetostratigraphy, radiometric dating, isotopic stratigraphy, etc.); and (3) extend morphometric criteria wherever possible to recognize the markers themselves. [ABSTRACT FROM AUTHOR]

A new larger benthic foraminifer, Asterigerina cayrazensis n. sp., is described from the upper Ypresian (middle- upper Cuisian) of the Çayraz section, N of Haymana, S Ankara, central Turkey, from which also the rotaliine species Ornatorotalia spinosa, O. granum and Granorotalia sublobata are first recorded. In addition, Ornatorotalia sp. is recorded from the Thanetian limestone of the Harabekayış section, W Elazığ, eastern Turkey. [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.

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]

Here, the larger foraminifera found in Middle Eocene-Early Miocene rocks from Dhofar (Oman) and Socotra Island (Yemen) are studied in detail. The architectural analysis leads to the description of five new genera and nine new species: five agglutinated foraminifera, Pseudolituonella robineti n. sp., Socotraella ashawqi n. gen. n. sp., Pseudoaccordiella ayaki n. gen. n. sp., Barattolites andhuri n. sp., and Rogerella aydimi n. gen. n. sp.; and four porcellaneous foraminifera, Idalina grelaudae n. sp., Idalina pignattii n. sp., Macetadiscus incolumnatus n. gen. n. sp., and Omanodiscus tenuissimus n. gen. n. sp. The larger foraminifera identified in a composite section located in western Dhofar, in the Shuwaymiyah section located in eastern Dhofar, and in the Wadi Ayak section located on Socotra Island have facilitated the identification of the following larger foraminifera zones: SBZ 14-SBZ 15 (middle Lutetian), SBZ 16 (late Lutetian), SBZ 17 (Bartonian), SBZ 18 (latest Bartonian-earliest Priabonian), SBZ 19-SBZ 20 (Priabonian), SB 21-SB 22A (Rupelian), SB 22B-SB 23 (Chattian), and SB 24 (Aquitanian). All these data permit to assess the age of the following lithostratigraphic units: Dammam Fm.-Andhur Mb. lower Lutetian?-middle Lutetian age (SBZ 13?-SBZ 14 partim), Qara Mb. middle Lutetian (SBZ 14-SBZ 15), and Uyun Mb. upper Lutetian (SBZ 16); Aydim Fm.-Heiron Mb. Bartonian (SBZ 17), Moosak Mb. upper Bartonian-Priabonian (SBZ 18-SBZ 20), Tagut Mb. Priabonian (SBZ 19-SBZ 20), and Haluf Mb. Priabonian (SBZ 19-SBZ 20) to lower Rupelian (SBZ 21) on Socotra Island; Ashawq Fm. Rupelian (SB 21-SB 22A); and Mughsayl Fm. Chattian-Aquitanian (SB 23-SB 24). [ABSTRACT FROM AUTHOR]