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The sedimentology, geochemistry and paleontology of the pelagic upper Campanian Maastrichtian Bozova Formation in the "Mazidag" (Mazıdağı) - Mardin area, SE Turkey, reveal paleoceanographic and paleoecological changes for the first time. A 119.25 m-thick composite stratigraphic section is characterized by alternating marls, clayey limestones, shales, and black shales; no coarse siliciclastic admixture or turbidite intercalations were recorded in the section. Biostratigraphic data indicate the presence of the Radotruncana calcarata Zone, and the UC15de/UC16 nannofossil zones. Stable isotope and elemental geochemical analyses have been carried out in the studied section. The isotope curves display similar patterns compared to reference curves from European and Chinese basins in the same interval. The prominent negative carbon isotope excursion determined in the upper interval can be correlated with the Late Campanian Event. Proxy elements display generally two relative rising trends in productivity from the lower part and the middle part of the succession. The lower part of the section records relatively more dysoxic/anoxic conditions and coincides with common black shale beds. The presence of both diverse planktonic foraminifera and calcareous nannofossils in the studied interval indicates a fully marine, warm-water, low-latitude Tethysian oceanic environment. In addition, the plant fossils derived from the nearby land mass indicate that a tropical humid climate was similar to that in northeast Australia. Therefore, warm water, tropical humid atmospheric conditions developed in the studied area causing the rise in productivity, precipitation and transportation of plant debris into offshore environments.

The name Paynita is proposed for a new dagmaritin genus from the upper Changhsingian (Permian) carbonates of the Southern Biofacies Belt in Turkey. Paynita permotaurica differs from its ancestor Paradagmarita monodi by a hook-shaped fold in the apertural flap terminating systematically against the inner surface of the septal wall to protect the opening from one chamber to the other. It is associated with several species of dagmaritins, belonging to Paradagmarita, Paradagmacrusta, Louisettita, Dagmarita, Danielita, and Bidagmarita. The overall analysis of dagmaritins reveals that the stratigraphic range of the group is from Wordian to Changhsingian. The revised chronostratigraphy in the type area of the genus Sengoerina indicates that this oldest dagmaritin was derived from Globivalvulina cyprica in the Wordian. The first occurrences of genera Dagmarita and Danielita postdate the first occurrence of Sengoerina in the Wordian. Paynita is the last evolutionary step of the Sengoerina-Dagmarita-Crescentia-Paradagmarita lineage characterized by a planar apertural flap whose structure practically remained unchanged during the process of evolution. Paynita is the first genus in this lineage displaying fold in the apertural flap similar to the evolution of Louisettita from Dagmarita.

Foraminifera are important components of tropical marine benthic ecosystems and their recovery pattern from the end-Permian mass extinction can yield insights into the Mesozoic history of this group. Here we report the calcareous and agglutinated foraminifera recovered from five measured stratigraphic sections on the Great Bank of Guizhou, an uppermost Permian to Upper Triassic isolated carbonate platform in the Nanpanjiang Basin, south China. The material contains >100 Triassic species, including three that are newly described (Arenovidalina weiin. sp.,Meandrospira?enosin. sp., andSpinoendotebanella lehrmannin. gen., n. sp.), ranging from Griesbachian (Induan) to Cordevolian (Carnian) age. The species belong to the classes Miliolata, Textulariata, Fusulinata, Nodosariata, and to an unknown class housing all aragonitic forms of the orders Involutinida and Robertinida. Based on previously established conodont zones and carbon isotope chemostratigraphy, the Griesbachian (early Induan) through Illyrian (late Anisian) interval has been subdivided into 12 foraminiferal zones and two unnamed intervals devoid of foraminifera. Following the extinction at the Permian-Triassic boundary, habitable ecological niches of Griesbachian age were invaded by disaster taxa that subsequently became extinct during the Dienerian (late Induan) and left no younger descendants. The disaster taxa were replaced by Lazarus taxa with Permian origins, which were then decimated by the Smithian-Spathian (mid-Olenekian) boundary crisis. The tempo of recovery appears to have been modulated by environmental changes during the Griesbachian through Smithian that involved both climate change and expansion of anoxic ocean bottom waters. Uninterrupted and lasting recovery of benthic foraminifera did not begin until the Spathian.UUID:http://zoobank.org/2a6e9061-b163-402a-9098-8765a80576b3

During the Cretaceous, vast amounts of marine sediments were deposited along the south-facing active margin of the Eurasia. A stratigraphic section of 91 m was analyzed for planktonic foraminifera (75 samples), with the aim of establishing a refined biostratigraphy of Cenomanian–Campanian deposits in Central Anatolia. A biostratigraphic framework comprising nine biozones was established. In ascending order, the Rotalipora cushmani, Whiteinella archaeocretacea and Helvetoglobotruncana helvetica zones were defined in the uppermost Cenomanian–Turonian interval. The lack of Coniacian index markers suggests the existence of a hiatus for this interval. In the upper part of the section, the Dicarinella asymetrica, Globotruncanita elevata, Contusotruncana plummerae, Globotruncanella havanensis and Globotruncana aegyptiaca zones were identified for the Santonian and Campanian deposits. The presence of Gansserina gansseri, Globotruncanita angulata, G. conica and G. pettersi in the uppermost part of the section shows that the section ends at the base of the Gansserina gansseri Zone, indicating uppermost Campanian. The planktonic foraminifera biozonation framework provides strong evidence for the timing of the depositional history of the active continental margin that developed south of the Pontides. These phases are mainly the formation of olistostromes of pre-Santonian age, following condensed carbonate deposition during the Santonian and finally the switch from forearc deposition to the formation of a thick sequence of siliciclastic succession starting in the Campanian.

The Cretaceous–Paleogene (K/Pg) boundary in the Haymana Basin, Central Anatolia, Turkey, was delineated using planktonic foraminiferal biostratigraphy, microfacies analysis, and sequence stratigraphy. An ∼ 29 m outcrop consisting of limestone and marl was measured, and four planktonic foraminiferal biozones were identified spanning the boundary. Planktonic foraminiferal extinction across the K/Pg boundary was catastrophic and abrupt. The extinction level is overlain by a unit (Zone P0) showing an increase in echinoid fecal pellets and authigenic clay minerals such as glauconite, suggesting low sedimentation rates in the early Danian. Ten microfacies types were identified indicating inner-ramp to basinal paleoenvironments based on the sedimentological characteristics and microfossil and macrofossil assemblages. Maastrichtian carbonates contain large benthic foraminifera, calcareous red algae, bryozoans, fragments of echinoderms and mollusks, and planktonic foraminifera. Overlying Maastrichtian–Danian silty marls and silty limestones have common planktonic and benthic foraminifera. Progradation of carbonates into the basin took place during the highstand systems tract, and deposition of a silty marl succession occurred during the transgressive systems tract. The K/Pg boundary is in the upper part of the transgressive systems tract, below a maximum flooding surface. Sequence stratigraphic analysis of a second section, Campo Pit, New Jersey, USA, showed that the K/Pg boundary occurs within a transgressive systems tract in New Jersey as well, suggesting a global sea-level rise across the K/Pg boundary.

The Haymana Basin, Turkey, hosts complete record of sedimentation across the Cretaceous-Paleogene (K-Pg) boundary. To examine the K-Pg boundary transition and delineate the bioevents, two consecutive sections (UH and UKHB) were measured and sampled at high resolution. Three biozones were established: Plummerita hantkeninoides, P0 and Pα. A detailed quantitative study on planktonic foraminifera was carried out for the P. hantkeninoides and the P0 zones for 63–150 μm and >150 μm size fractions. Results show dominance of ecological generalists with small, simple tests over ecological specialists with large, robust, ornamented morphologies. Heterohelicids are the most dominant group on both size fractions throughout the late Maastrichtian, however right after the K-Pg boundary Guembelitria cretacea blooms and dominates the planktonic foraminiferal assemblage in early Danian P0 Zone. The K-Pg boundary characterizes itself as 2–3 mm thick reddish oxidized layer and its transition reveals a series of events: A rapid change in sedimentation from Maastrichtian mudstones to Danian marls. A sudden annihilation of large, ornamented ecological specialists (e.g., Globotruncana, Rugoglobigerina, Planoglobulina) right at the reddish layer (even though quantitative study revealed that there is a systematic reduction in the foraminiferal species richness throughout the P. hantkeninoides Zone). Spikes of calcareous dinoflagellate Thoracosphaera and fecal pellets right after the K-Pg boundary in the Danian P0 Zone. Anomalous increase in CaO rich spherules and amorphous grains coupled with barite crystals right at the K-Pg boundary layer. Paleobathymetric calculations also revealed approximately 400 m paleodepth for the study area corresponding the upper bathyal zone.

Necdetina (type species N. taurica n. sp.) is described here as a new fusulinoidean genus with a replaced or recrystallized wall from the Middle Permian (Capitanian) of Turkey. In addition to its distinctive wall structure, which was probably originally keriothecal and composed of aragonite or high-Mg calcite, the genus is characterized by an ovate shell with rounded to acute poles and axially elongated, biserially enrolled chambers. Chomata are absent, but inconsistently developed parachomata-like structures are present in the test where biserially enrolled chambers overlap. Circular foramina alternate in two rows at the bases of the apertural face and septa. Phylogenetic analysis indicates that Necdetina belongs in the clade of staffellid fusulinoideans, a group whose walls are invariably altered. Among the staffellids, Necdetina is allied with other genera in which the coiling axis is elongated to produce a spherical, oval or fusiform test. In this subclade, Necdetina is further united with Thailandina and Neothailandina in possessing parachomata and having well-organized foramina along the antetheca and septa. Necdetina is the only known staffellid, indeed the only known fusulinoidean, with biserial chambers.

The name Charliella is proposed for a new biseriamminid genus characterized by a four-layered wall that thickens along the anterior side of the septa and partially occludes the chamber cavity. Charliella rossae was derived from the Globivalvulina graeca-Globivalvulina vonderschmitti lineage which also constituted the root stock of true Paraglobivalvulina ( P. mira ) in Late Permian time. The Globivalvulina decrouezae-Septoglobivalvulina gracilis-Paraglobivalvulinoides septulifer lineage is another trend in the evolution of biseriamminids. The recognition of such a lineage in the Late Permian necessitates taxonomic revision of the biseriamminids to attribute globular and involute forms with thin and undifferentiated walls to Septoglobivalvulina, a genus which was synonymized under Paraglobivalvulina in previous work.

Early ontogenetic morphologic features previously recognized as evolutionary parameters in Lepidorbitoides and Orbitoides have been tested in several flysch successions of Anatolia. Increase in embryo size (Li+li), number of epi-embryonic chambers (E) and organization of embryonal chamber arrangement from ‘quadrilocular’ to ‘bilocular’ and multilocular in Orbitoides, increase in deuteroconch size (D), in deuteroconch–protoconch ratio (D/P) and in number of adauxiliary chambers (Ad) in Lepidorbitoides have been recognized as the main evolutionary trends, thus allowing the correlation of these features with time. The different developmental stages in Lepidorbitoides, i.e. L. pembergeri, L. campaniensis, L. bisambergensis, L. minor, L. socialis, and in Orbitoides, i.e. O. media, O. megaloformis, O. gruenbachensis, O. apiculata and O. gensacicus, have been described and illustrated based on the biometry of the populations. The values observed in some horizons, however, may not reflect the true phylogenetic stage of the orbitoidal taxa, especially in the species of Orbitoides, which usually show a wide variation of evolutionary parameters in the same population. A correlation scheme of phylogenetic development in Lepidorbitoides and Orbitoides with the planktonic foraminiferal zones is proposed. Lepidorbitoides populations with highly asymmetric ‘quadriserial’ nepionts occurring stratigraphically below the symmetric ones in Early Maastrichtian are thought to deserve a particular taxonomic status. In Orbitoides, a new embryonal chamber morphology previously undescribed from horizontal sections has been discovered. Copyright © 1999 John Wiley & Sons, Ltd.

Evolution of Lepidorbitoides in some flysch basins of Anatolia has been investigated considering the early ontogenesis in horizontal sections. Different developmental states of L. permbergeri, L. campaniensis, L. bisambergensis, L. minor and L. socialis have been described and illustrated with their morphometric features based on the earliest chamber arrangement. A correlation scheme of phylogenetic developmental states of Lepidorbitoides to the planktonic foraminiferal zones is also proposed. Populations with highly asymmetric quadriserial nepionts identified stratigraphically below the symmetric ones in Early Maastrichtian are thought to deserve a new status and attributed to L. bisambergensis asymmetrica n. spp. Orbitoides in common association with Lepidorbitoides has also been studied for the evolution of embryo-related parameters such as embryo size (Li + Ii), number of epi-embryonic chambers (E) and other embryonal features to correlate the phylogenetic developmental state of both genera., The authors would like to acknowledge the Scientific and Technical Council of Turkey for funding the project (T1JBiTAK, YDAB~AG-69) "Microfacies variations around Cretaceous-Tertiary boundary: An integrated zonation of calcareous nannofossil, planktonic foraminifera and benthic foraminifera" related to the subject of this paper.

WOS: 000085050300006, Planktonic and larger benthonic foraminifers of the Upper Cretaceous (Santonian-Maastrichtian)-Lower Tertiary (Danian) rock units from north, northwest and central Anatolian fore-are basins have been investigated in order to improve the biostratigraphic resolution of this time interval. Total abundance and diversity of planktonic foraminifers vary from rare (the sequence from the Haymana region) to high (the sequences from the Cide, Caycuma, Hanonu and Yenikonak regions) and preservation is poor to moderate due to lithologic variation. First and last appearances of the planktonic foraminifera evaluated as major bio-events have been used to establish the biostratigraphic framework. Planktonic foraminiferal zonation from bottom to top of the succession consists of zones defined by Dicarinella concavata, Dicarinella asymetrica, Globotruncanita elevata, Globotruncana, ventricosa, Radotruncana calcarata, Globotruncanella havanensis, Globotruncana aegyptiaca, Gansserina gansseri, Abathomphalus mayaroensis and Morozovella pseudobulloides. Ten Orbitoides and Lepidorbitoides species have been identified. The different phylogenetic development stages of Orbitoides and Lepidorbitoides populations and other larger benthonic foraminifers, Pseudosiderolites vidali, Siderolites calcitrapoides, Siderolites denticulatus, Omphalocylus macroporus, Cideina sozerii, Hellenocyclina beotica, and Clypeorbis mamillata have been calibrated with the planktonic foraminiferal zonation established in the same successions. Hence, an integrated zonational scheme composed of planktonic foraminifers and larger benthonic foraminifers has allowed a detailed stratigraphy of these successions to be erected. Copyright (C) 1999 John Wiley & Sons, Ltd.