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Ostracods of the Ordovician and Silurian transition interval in the JÅ«rmala section, Latvia, were studied. The diverse pre-Hirnantian ostracod assemblage is replaced by the Harpabollia harparum association that has been recorded across the Baltoscandian region and northwestern Poland and is confined to the Hirnantian. The first complete ostracod succession throughout the KuldÄ«ga and Saldus formations reveals a remarkable diversity decline and rise of dominance of ostracods in this interval. The appearance level of the H. harparum association in other sections is drawn distinctly above the range of Spinachitina taugourdeaui, nearly coinciding with the appearance of Conochitina scabra and Noixodontus girardeauensis. The transition from the Saldus Formation into the StaÄiunai Formation marks a complete ostracod turnover. The newly appearing assemblage, dominated by Longiscula smithii, is of low diversity. Slow diversity rise may in part be ascribed to the overall low recovery rate of post-glaciation faunal assemblages. The shape of the stable carbon isotopic curve in the JÅ«rmala core suggests that this section is one of the most complete successions across the OrdovicianâSilurian boundary in the Baltoscandian area. The correlation of this curve with that of the Monitor Range, Nevada, and comparison with other curves of Latvia and Estonia suggest that the well-known appearance level of the âSilurian faunasâ is confined to the upper M. persculptus graptolite Zone. Judging from the chemostratigraphic correlation, the latter zone ranges for more than 10 m into the StaÄiÅ«nai Formation in the JÅ«rmala core.

International audience; This paper presents the first Lateglacial/Holocene (the last 13 500 cal a BP) ostracod δ18O record to infer hydroclimate variability in the Southern French Alps. Cytherissa lacustris (δ18Osp) shells extracted from the sediments of Lake Allos allowed a reconstruction of δ18Olake water (δ18Olw) except for the interval 5800–2800 cal a BP. The shape of the Younger Dryas (YD) clearly differed from records documented in the northern Alps. First, δ18Olw values remained close to modern values before a marked drop ca. 12 000 cal a BP. Then, after several oscillations, δ18Olw values increased, reaching the highest value of the record ca. 6100 cal a BP during a thermal optimum for this latitude. Finally, low δ18Olw values occurred from 450 to 100 cal a BP during the Little Ice Age (LIA) following the MedievalClimate anomaly. At the beginning of the YD, δ18Olw probably reflected changes in local glacier dynamics and precipitation sources. The following decrease in δ18Olw values was associated with higher freshwater inputs during the second half of the YD. During the LIA, the low δ18O values are consistent with a higher torrential activity and lower air temperatures

Made available in DSpace on 2022-04-28T19:41:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-11-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Unlike other South American basins, the boundary between Ordovician and Silurian in the Paraná Basin, Brazil, has yet to be studied in detail. This article reports the occurrence and taphonomic analysis of a fauna composed of the organophosphatic brachiopods Kosoidea australis and ?Palaeoglossa sp., the mollusks ?Paleoneilo sp. and ?Cuneamya sp., besides rynchonelliform brachiopods and the ostracods Harpabollia sp. and Satiellina paranaensis. This assemblage indicates a Hirnantian age for the top of the Iapó and the base of the Vila Maria formations, northeastern border of the Paraná Basin. Taphonomic signatures and facies associations point to a pro-glacial environment, at the transitional shoreface, represented by the last sedimentary facies of the Iapó Formation. The overlying transgressive strata represent the beginning of the Vila Maria Formation, in which fossils and lithofacies indicate predominant post-glacial conditions in an offshore setting. Two taphofacies were delineated. One features size- and type-selected fossils, deposited in rain-out facies originated from the melting glacier. The second, with autochthonous to parautochthonous fossils, represents a post-glacial offshore setting. The low faunal diversity points to marine connections between North and South African basins, and with South American basins. Geosciences Institute UNICAMP, Campinas Geosciences Institute University of Brasilia Center for Technological Innovation-CEDES Setor Bancário Norte Department of Geology São Paulo State University Unesp Department of Geology São Paulo State University Unesp FAPESP: 2017/10956-5 CNPq: 459776/2014-2

Understanding Quaternary dynamics of delta-coastal plains across multiple glacial-interglacial cycles in the Milankovitch band (~100 kyrs) is crucial to achieve a robust evaluation of possible environmental response to future climate-change scenarios. In this work, we document the long-term bio-sedimentary record of core 204 S16 (~205 m long), which covers a wide portion of the post-MPR (Mid-Pleistocene Revolution) interval, taking advantage of the highly subsiding context of the SE Po Plain (NE Italy). Detailed facies characterization through an integrated sedimentological and meiofauna (benthic foraminifers and ostracods) approach allowed for the identification of a repetitive pattern of alluvial deposits alternating with four fossiliferous, paralic to shallow-marine units (Units 1–4). The transgressive surfaces identified at the base of these units mark major flooding events, forced by Holocene (Unit 4), Late Pleistocene (Unit 3) and Middle Pleistocene (Units 1, 2) interglacials. Distinct stratigraphic patterns typify the Middle Pleistocene interval, which includes coastal-marine (tidal inlet and bay) deposits. In contrast, lagoonal sediments record the maximum marine influence in the Late Pleistocene-Holocene succession. As a whole, the meiofauna tracks a regressive trend, with the deepest conditions recorded by the oldest Unit 1 (MIS 9/11 age?).

The Dacian Basin was uniquely situated to record late Miocene hydrological changes that influenced depositional environments and faunal dispersal patterns in Central Eurasia's mega-lake Paratethys. Differences between the high strontium isotope ratio (87Sr/86Sr) of the waters from Lake Pannon and local Carpathian rivers and low 87 Sr/86Sr of the Eastern Paratethys (Black Sea ‒ Caspian Sea) allow a thorough investigation of connectivity and water fluxes in the transient Dacian Basin. We present a detailed 87Sr/86 Sr record for the Dacian Basin, which provides an exceptional record of basin connectivity from the latest Tortonian (ca. 7.7 Ma) until the early Pleistocene (ca. 1.8 Ma). Data show that a late Tortonian transgression (7.6–7.4 Ma) started with an incursion of Eastern Paratethys waters into the Dacian Basin, after which local rivers became the dominant source for the mostly freshwater environments of the early Messinian. The regional Maeotian-Pontian transitional interval (6.3–5.9 Ma) records a second incursion of Eastern Paratethys waters, but this time with an additional marine (Mediterranean) influx coinciding with a short-lived salinity incursion. During the Messinian Salinity Crisis of the Mediterranean, the Dacian Basin progressively connected with the Eastern Paratethys (5.9–5.5 Ma), after which it became restricted during the peak Mediterranean lowstand (5.5 Ma) and filled with Lake Pannon and local river water (5.5–5.3 Ma). During the Plio-Pleistocene, the Dacian Basin reconnectedwith the, at that time isolated, Black Sea, which shows similar 87Sr/86Sr as in the Last Glacial Maximum.

Ostracoda, minute aquatic crustaceans with calcitic shells, are highly versatile proxies in geoarchaeological contexts. Their species-specific ecological preferences and ranges allow the reconstruction of palaeoenvironments and anthropogenic impacts in detail. Environmentally driven morphological variability and shell chemistry signatures as stable isotope and trace element values can provide additional palaeoenvironmental information. Ostracods can be used for provenance analyses and stratigraphical investigations as well. Their small size and high abundance in most water bodies makes them ideal for studying sediment cores and smaller samples from trenches or outcrops, especially in coastal areas where they show a high diversity and abundance compared to other groups of meiofauna. In archaeological contexts, fossil ostracods may provide information about climate, sea level and hydrography, high energy events like storms or tsunamis, ocean currents, land use, pollution, water constructions, stratigraphy, trade connections or the origin of sediment material. We give an overview on the state of ostracod-based research in geoarchaeology today and present some European case studies to illustrate concepts and methods of such field of study.

New palynological, ostracod and foraminiferal data are presented from a long outcrop section in the Jeirankechmez river valley, Azerbaijan, near the western coast of the Caspian Sea. The interval studied includes the upper part of the Pliocene Productive Series and overlying Plio-Pleistocene Akchagylian (Akchagyl) and Apsheronian (Apsheron) regional stages. Productive Series sediments were deposited in a closed fluvio-lacustrine basin, isolated from any marine influence. The onset of Akchagyl deposition is marked by a lithological change associated with a significant flooding event that, at its maximum extent, reached the Sea of Azov and into present-day Iran, Kazakhstan, Turkmenistan and Russia. At the Jeirankechmez locality, the lowermost beds of the Akchagyl contain predominantly freshwater assemblages with very minimal marine or brackish content showing that the onset of Akchagyl deposition was not a marine induced event. Reworked Mesozoic palynomorphs occur frequently in this lowermost interval, including the reworked pollen taxa Aquilapollenites-Triprojectus that were eroded from the north or north-east.Significant marine influence is evident ca. 30 m above the base of the Akchagyl in the studied outcrop, marked by the ‘Cassidulina Beds’ which contain a distinct but low diversity assemblage of foraminifera that occurs widely and can be correlated in many parts of the greater Caspian region. Dinoflagellate cysts (dinocysts) in the marine interval include frequent specimens very similar to Algidasphaeridium capillatum (Matsuoka and Bujak), a species only previously recorded from the northern Bering Sea. The combined evidence from these dinocysts and foraminifera suggests that a marine (i.e. seaway) connection existed briefly between the Arctic Ocean and the Caspian Sea at the very end of the Pliocene.Re-examination of core material from the Adriatic Sea shows that Cassidulina reniforme (Nørvang) was present in the Mediterranean during and shortly after the Last Glacial Maximum. The possibility that the end Pliocene marine incursion came from the Mediterranean via the Black Sea region to the Caspian Sea cannot be entirely ruled out but is considered unlikely. Biometric analyses are applied to obtain a better understanding of the palaeoenvironmental significance of the assemblages dominated by cassidulinids.An interval >300 m thick is assigned to the Apsheron regional stage on the basis of predominantly brackish ostracod and dinocyst associations. The dinocysts are of ‘Peri-Paratethyan’ affinity and closely resemble species first described from Miocene and Pliocene sediments in the Pannonian and Dacic basins of Eastern Europe. Many similarities exist in the microplankton records (dinocysts and acritarchs) between the Caspian Sea, the Black Sea and Central Paratethys.

This study is aimed at comparing ostracod assemblages during the Eocene-Oligocene transition that were identified in the Paleogene succession at twenty-two previously studied locations across the seven geographical regions of Turkey. The formations deposited in the Eocene-Oligocene and the paleogeographic distribution and paleoenvironmental properties of the ostracods that were identified in these formations were investigated in the following different geographical regions of Turkey: the Aegean (Denizli), the Eastern Mediterranean (Mut, Karsantı Baseni), Southeastern Anatolia (Adıyaman), Eastern Anatolia (Malatya-Darende, Elazığ), Central Anatolia (Karaman, Ulukışla, Sivas, Ankara), Northern Anatolia (Batı Pontidler/Kastamonu) and Northwestern Anatolia (İstanbul, Çatalca/GD Trakya, Kırklareli, Tekirdağ). The ostracod biozones in the acme-zone category were studied in these geographical regions. The zones were identified and chosen by successions or rock assemblages. The study revealed that the Eocene-Oligocene ostracod species demonstrated lacustrine, lagoonal, lagoon-littoral, epineritic, epineritic-infraneritic and infraneritic-bathyal environmental conditions. It was observed that, especially in the Aegean, Northwestern Anatolia and Southern Anatolia/Eastern Mediterranean regions, marl and silty sandstone in the upper and bottom levels of the Oligocene, in which coal settlement is observed, were usually deposited in lagoons containing ostracods. Furthermore, in the studied regions the co-occurrence of ostracod species living in maritime conditions with ostracod species living in lagoonal conditions can be explained by sea-related excessive shoaling in the basins. In Turkey, judging from environmental properties of the ostracod species, the transgression of the sea declined from northeast to northwest during the Eocene–Oligocene. © 2018, Pleiades Publishing, Ltd.

Previous studies made in different parts of the world have shown that Barremian–Aptian times imply many difficulties in deciphering the biostratigraphy, microfossil evolution and correlation of bioevents. In an attempt to improve our knowledge of this period in a particular area of the Tethyan realm, we present the first integrated study of microbiota (including planktonic foraminifera, calcareous nannofossils, ostracods and palynomorphs) and magnetostratigraphy of the upper Barremian–Aptian sediments from south-eastern Crimea. The nannofossils display the classical Tethyan chain of bioevents in this interval, while the planktonic foraminifera demonstrate an incomplete succession of stratigraphically important taxa. Our study enabled the recognition of a series of biostratigraphic units by means of four groups of microfossils correlated to polarity chrons. The detailed analysis of the microfossil distribution led to a biostratigraphic characterization of the Barremian/Aptian transition and brought to light an interval, which may correspond to the OAE1a.

A new accerator mass spectrometry (AMS)‐dated sedimentary record from Lake Ochaul (54°14′N, 106°28′E; 641 m a.s.l.) in Eastern Siberia covers the interval from ca. 27 850 to 20 400 cal a bp at ca. 180‐year resolution and contributes to a better understanding of the complex spatial vegetation pattern during the Last Glacial Maximum (LGM). Non‐arboreal pollen taxa are abundant in the pollen assemblages (mean value ca. 92.6%), but boreal trees are represented by all major taxa that grow in the lake catchment today, including Betula sect. Albae (0.6–4.8%), Picea (0.6–2.8%), Pinus sibirica (Haploxylon type) (up to 1.5%), Pinus sylvestris (Diploxylon type) (up to 2%), Larix (up to 0.6%) and Abies (up to 0.6%). Betula sect. Nanae/Fruticosae (2–5.2%) and Salix (up to 3.2%) are the most representative boreal shrub taxa. Together with existing modern and fossil pollen data from the wider study region, the current record provides further evidence for the long‐debated presence of boreal trees and shrubs in Eastern Siberia throughout the LGM. Our results show that the Upper Lena was a region in which refugia for arboreal taxa existed and that far‐distant pollen transport can be ruled out as the source of the detected arboreal pollen., Government of the Russian Federation, Social Sciences and Humanities Research Council of Canada http://dx.doi.org/10.13039/501100000155, Russian Foundation for Basic Research http://dx.doi.org/10.13039/501100002261, Siberian Branch, Russian Academy of Sciences http://dx.doi.org/10.13039/501100003182, Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences, Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, Russian Science Foundation http://dx.doi.org/10.13039/501100006769

We present the geological map of the north-eastern margin of the Fucino Basin, which is mainly characterized by Plio-Quaternary continental deposits that show transition from deeper-water lacustrine environment, marginal lacustrine system, and fluvial facies. These deposits unconformably overlie upper Messinian Lago-Mare sediments and pre-orogenic carbonate succession. The occurrence of Caspiocypris tiberina in the Plio-Quaternary lacustrine sediments, coupled with the normal magnetic polarity of Casa Colombaia section, led to suggest the onset of the sedimentation of these continental deposits to the late Piacenzian (2.58–3.04 Ma). The upper Messinian deposits are characterized by ostracod assemblages related to the Loxocorniculina djafarovi zone, pointing to the last Lago-Mare event of the Messinian Salinity Crisis (5.40–5.33 Ma). This new stratigraphic framework may be useful to refine the long-term slip rates of the still active normal faults that affect the north-eastern margin of the Fucino Basin.

The upper Miocene – lower Pliocene sedimentary succession of the Denizli Basin (SW Anatolia) displays a unique record of undisturbed stratigraphy and provides an excellent opportunity to study long-term palaeoecological changes. This paper documents the ostracod assemblages of two sections of the Neogene Kolankaya Formation, resulting in the following taxonomic, palaeobiogeographic and ecological interpretations. The ostracod assemblages from the two sections consist of a mixture of oligohaline to mesohaline tolerant taxa but expose fundamental differences in their composition. This is reflected by the fact that out of 32 determined species, both sections only have 3 in common. In the stratigraphic older succession, the diverse ostracod fauna resembles taxa known from the Paratethys. Faunal relations to the brackish lake habitats of the Euxinic and Pannonian basins are apparent and the palaeobiogeographic significance of the fauna is discussed. The ostracod association of the younger section indicates a low brackish water habitat with fluctuating salinities, most likely in the oligohaline range. The ostracod assemblage of the Kolankaya Formation only permits a broad age assignment to the late Miocene – early Pliocene.

International audience; The present study evaluates the significance of Triassic ostracods from the Romanian Black Sea shelf as part of a project for the understanding of the palaeoceanographical evolution of the offshore extension of the North Dobrogean Orogen. The drill core CM31, sampled from the borehole 817 Lebăda Vest drilled on the western Romanian portion of the Black Sea shelf, contains sediments of Rhaetian, Late Triassic age. The taxonomy of ostracods obtained is discussed and adds to the scientific understanding of marine ostracods during the Rhaetian stage. We document 72 species, of which seven are new: Histriabairdia pontuseuxinusensis Forel gen. et sp. nov., Bairdiacypris argonautaii Forel sp. nov., Ceratobairdia? akhilleusi Forel sp. nov., Isobythocypris atalantella Forel sp. nov., Petasobairdia amazonella Forel sp. nov., Paracypris ovidi Forel sp. nov. and Pseudomacrocypris? kerabani Forel sp. nov. Histriabairdia Forel gen. nov. is introduced to accommodate species of the Triassic–Jurassic interval previously attributed to the modern genus Anchistrocheles. These assemblages point to an outer shelf environmental with relatively normal marine oxygenation. The oldest occurrence of Pokornyopsis, found in this material, indicates that this forerunner of modern troglobitic ostracods may not have been troglobitic in the Triassic.

Burmese Cretaceous amber (∼99 Ma, Myanmar) is famous for the preservation of a wide range of fauna and flora, including representatives of marine, freshwater and terrestrial groups. Here, we report on three ostracod specimens, that came visible as syninclusions to an aquatic isopod. The three specimens represent three different taxa, that were found preserved in a single piece of amber. One of the described specimens was studied using µCT scanning data. On the basis of general carapace morphology we assign all three to the group Podocopida, and (tentatively) its ingroup Cypridocopina. A lack of visibility of more particular diagnostic features such as adductor muscle scars and details of the marginal zone precludes a further identification, but we discuss possible affinities with either the marine-brackish group Pontocypridoidea or the non-marine group Cypridoidea. The taphonomy indicates that the studied ostracods had been subject to limited (if any) post-mortem transport, which could be consistent with marginal marine environments.

International audience; The Triassic has been a turning in the history of biodiversity: bracketed by two major biotic crises, characterized by major biotic, climatic and tectonic events, it has seen the transition from the Palaeozoic to the Modern evolutionary faunas. We propose the first synthetic analysis of the diversity of marine and brackish-water ostracods over the entire Triassic, in the light of palaeoecological, palaeoenvironmental and palaeogeographical contexts. Although general diversity trends witness poor ostracod communities during most of the Early Triassic after the end-Permian crisis, the roots of their Triassic taxonomic rediversification are visible as early as the Dienerian. The explosive diversification of the Spathian and Anisian is followed by a high-diversity plateau up to the brink of the end-Triassic extinction. A "morphological phylogeny" proposes that all Permian and Triassic ornate Bairdiidae derived from Petasobairdia in the Kungurian, with the emergence of the Ceratobairdia-lineage and Abrobairdia-lineage. While they are generally the "poor cousin" of trophic chains analyses, traces of typical Mesozoic drilling predation on Late Triassic ostracods unexpectedly document the increase of the efficiency of predators drilling abilities through the Triassic. Finally, the palaeogeographical distribution of ostracods as been very dynamic during this interval, with distinct peri-palaeo-tethyan and peri-neo-tethyan biotas in the Early Triassic, followed by a dispersal and thus a relative homogenization from the Anisian onwards.

The Eastern Paratethys represents a large epicontinental sea that was spread on a vast territory of West Eurasia. In the late Miocene, intensification of regional orogenic processes and enhanced climatic oscillations isolated and segmented this sea into two small remnants – the Black and Caspian Seas, combined also known as Pontocaspian region. The transition from Paratethys to Pontocaspian system was accompanied by a complex history of interbasinal connections, basin-level drops and expansions, and biological turnovers that eventually shaped the modern endemic Pontocaspian ecosystems. Faunal migration paths, relations between taxa and drivers of ecosystem remain unclear, however, often due to the lack of robust age constraints and interdisciplinary studies. This thesis aims at dating and reconstructing the paleoenvironmental conditions responsible for the major biological turnovers in the region. It focuses on three key-intervals on a west-to-east transect: the late Miocene (~7.7 –6.0 Ma) of the Dacian Basin of Romania; the Miocene–Pliocene transition (~6.0–5.2 Ma) in the Denizli Basin of Turkey; the latest Pliocene–Middle Pleistocene (~2.7–0.5 Ma) in the Kura Basin of Azerbaijan. The new data especially shows that short episodes of re-established connection with intra-Paratethyan basins and with the global ocean triggered changes in the hydrological balance and water salinity, facilitating invasions of new faunal groups. This study thereby contributes to the refinement of the regional stratigraphic time scale that will serve as a backbone for further palaeoenvironmental studies.

Ostracods are described for the first time from the red-coloured marine sandstones of Arisu section (Arisu red beds) of the Upper Ordovician Tierekeawati Formation in Kalpin area of northwestern Tarim Basin, Xinjiang Uygur Autonomous Region (Xinjiang), Northwest China. Twenty-two species belonging to thirteen genera are described and figured. The ostracod fauna suggests a probable Sandbian–Katian age for these beds. The palaeoecological assemblage of ostracod fauna implies the deposition in a nearshore-offshore environment during a regression when the Arisu red beds of the Tierekeawati Formation were laid down in the Tarim Basin. Many cosmopolitan and provincial genera were present in diversified ostracod fauna of the Arisu red beds, suggesting the possible biogeographic relationships among the Tarim, Tibet, and South China plates, as well as Europe and North America continents during the Late Ordovician. Ostracods experienced faunal exchanges between Laurentia and the Tarim Plate during the Late Ordovician Period.

This study investigates the ostracod assemblages obtained from a sediment core from a paleolake in the Saglik plain in south-central Anatolia (Turkey). In addition to ostracods, oxygen and carbon stable isotopes of ostracod shells were analysed and pollen analysis of the core undertaken. The sediments comprise the Late Glacial and early Holocene interval with an approximate 14C age from 18,000 to 6700 14C years ago, after applying a correction for reservoir effects. Eight podocopid ostracod species were recorded, among them Cyprideis torosa and Candona sp. which were used for stable oxygen and carbon isotope analyses. C. torosa dominated during the Late Glacial while Candona sp. dominated most of the early Holocene assemblages. Both forms of C. torosa disappear abruptly close to the onset of the Holocene. Around this time, ostracod preservation was dominated by many black coloured valves and carapaces. Based on ostracod assemblage data and isotope analyses, relatively wet phases were identified for the Older Dryas, Younger Dryas, and during the mid-Holocene at around 7500 14C years ago. Relatively dry phases were identified during the Allerod interstadial, at the end of YD, and at about 6700 14C years ago. An oligotrophic and brackish lake persisted until shortly before the end of the YD, when, according to the δ 13C values, conditions gradually became more eutrophic. The sudden disappearance of C. torosa at the end of the YD seems the consequence of anoxic bottom water conditions and/or eutrophication. Alternating wet and dry phases characterize the early Holocene, with a longer period of wet and oligotrophic conditions around 7500 14C years ago (ca. 8300 calBP). Ostracod assemblages and isotope records indicate a dry and more productive lake around 6700 14C years ago (ca. 7550 calBP).

Ostracod associations coming from the Upper Triassic (Tropites subbullatus/Anatropites spinosus zones of the Tuvalian substage) clays and sandstones of the Mufara Formation outcropping along the west side of Monte Gambanera (Castel di Iudica, central-eastern Sicily) have been analysed for the first time. The specimens are relatively abundant, silicified, well preserved and often preserved as complete carapaces. Over 200 specimens have been determined. They belong to the families Healdiidae, Bairdiidae, Bythocyprididae, Acratiidae, Cytheruridae, Limnocytheridae, Candonidae, Cavellinidae, Polycopidae and Thaumatocyprididae. Thirty-seven species are identified of which nine species are new: Hungarella forelae n.sp., Hungarella siciliiensis n.sp., Bairdia andrecrasquini n.sp., Bairdia gambaneraensis n.sp., Ptychobairdia iudicaensis n.sp., Ptychobairdia leonardoi n.sp., Petasobairdia jeandercourti n.sp., Kerocythere dittainoensis n.sp. and Mockella barbroae n.sp.

The first ostracods known from the Lycian Nappes in southwestern Turkey are here reported, adding to the scientific understanding of marine ostracods during the Cordevolian, early Carnian, Late Triassic. The Karapınar Formation exposed at the Ağılıovası Yayla section yielded five species, including the typical Late TriassicMirabairdia longispinosaKristan-Tollmann,Nodobairdia mammilataKollmann andPolycope pumicosa schleiferaeKozur. Their taxonomy is discussed and the ontogenetic development ofNodobairdia mammilatais described for the first time. In spite of the limited significance of this poor fauna for palaeoenvironment reconstitution, it points to a deposition in the offshore subtidal zone under moderate water depth, in line with previous interpretations. The palaeobiogeographical distribution of marine ostracods during the Late Triassic is updated and discussed. It implies that communication ways between the Palaeotethys and Neotethys oceans were already opened during the Cordevolian, slightly earlier than the Julian as previously proposed.

The return to normal marine conditions in the Mediterranean Sea after the end of the Messinian Salinity Crisis (MSC), that led to the deposition of thick evaporitic succession followed by settlement of brackish to freshwater conditions of the “Lago-Mare”, is still subject to extensive debate between two opposite scenarios. One scenario implies an abrupt reflooding through the Gibraltar gateway of the Mediterranean Sea previously disconnected from the world ocean and partly desiccated. The second scenario postulates that the Mediterranean Sea kept a high-water level throughout the Messinian Salinity Crisis and was connected continuously to the Atlantic Ocean and to the Paratethys. The stratigraphic record of the classical Cuevas del Almanzora section (Vera Basin) is of a crucial importance as the Vera Basin is located on the eastern margin of the Alboran Sea close to the Gibraltar gateway where Atlantic waters reflooded the Mediterranean Sea after the MSC. The present new study completes previous investigations ( Pierre et al., 2006 ) and is mostly focused on detailed sedimentological observations, analysis of ostracod and foraminifer assemblages and on stable isotopes study of three species of planktonic foraminifers (Globigerina bulloides, Globigerinoides obliquus s.l. and Sphaeroidinellopsis spp.) from the lower Pliocene deposits. Biostratigraphical correlations with the reference deep-sea section from ODP Site 975 (Balearic Basin) and the onshore succession of Eraclea Minoa (Sicily) provide an accurate chronostratigraphy and paleoclimatic reconstruction during the Zanclean. During the late Messinian, the Vera Basin was characterized by very unstable lacustrine to brackish environments with significant water depth variations and the deposits display evidences of subaerial exposure. The ostracod content is dominated by Loxocorniculina djafarovi and Cyprideis gr. agrigentina associated to reworked planktonic foraminifera from older sediments. The Messinian/Zanclean contact is well marked by a clear erosional surface that grades laterally into a megabreccia with reworked gypsum blocks and to the large incision of the Palomares canyon in the offshore domain. The marine reflooding occurred abruptly with a sea level rise by more than 250 m, an important value for a marginal basin. In this western part of the Mediterranean Sea, the marine invasion began with the onset of the lowermost biozone MPl 1 at the base of the Zanclean. The fluctuations of the planktonic foraminifer assemblages and of their stable isotopes allowed to identify five lithological cycles forced by Milankovitch’ precession periodicity, as well as paleoclimatic variations through the lower part of the Zanclean. Thus, these new data allow us to reaffirm that the Messinian/Zanclean boundary corresponds to a major change, characterized by an “instantaneous” restoration of marine conditions at the onset of the Pliocene, related to the abrupt re-flooding of the Mediterranean Sea from the Atlantic Ocean.

Micropalaeontological analyses were performed on two stratigraphical sections sampled in upper Messinian deposits outcropping in eastern Tunisia, allowing us to identify some sedimentary levels with high concentrations of fresh or brackish water ostracods, which can be referred to the Lago-Mare fauna. Some of these species can be considered Paratethysian, or rather as species that spread in the Mediterranean area starting from the Paratethys areas, while others show Paratethysian affinity. The Lago-Mare fauna is little known in the south Mediterranean regions and the present article provides new data on its geographic distribution. Of the two sections sampled, the first one, the Wadi El Kebir section, is located in the south eastern part of the Cape Bon Peninsula and shows horizons dominated by Cyprideis agrigentina and Cyprideis ex C. torosa group; the second one, the Salakta section, is located in the Sahel region and shows a level with a very rich Lago-Mare ostracod fauna consisting essentially of Amnicythere propinqua, Mediocytherideis punctata, and Ilyocypris gibba.

International audience; Through geological times, the main turnover of marine ostracod group occurred at the Permian-Triassic boundary (PTB) when the Palaeozoic world gave way to Meso-Cainozoic world. As quite all the groups, ostracods intensively suffered of the end Palaeozoic events but they have the particularity to pass the PTB and to be present in quite all marine environments. We have studied the ostracod assemblages from the best preserved marine Permian-Triassic sections through the world. These sections are, for most of them, located along the Palaeo-Tethys margins: South China Block and Tibet (R.P. China), Bükk Mountains (Hungary), Dolomites (Italy), Taurus Mountains (Turkey) and Elbourz Mountains (Iran). These areas present different environmental settings from very shallow water to deep shelf. The biostratigraphy is well constrained by the presence of conodont index. In deep environment from external shelf to slope, all the Permian ostracods disappear slightly before the PTB and are absent from the Early Triassic. The last representatives of palaeopsychrospheric forms occur in the Early Anisian. On the platforms, during the Late Permian, the ostracods are abundant and highly diversified everywhere along Peri-Tethyan margins. The typical Palaeozoic forms are mixed with the very first Meso-Cainozoic representatives. The specific extinction rates, in the latest Permian, vary from 74% to 100%. During the earliest Triassic, two different settings have to be considered: with or without microbialitic deposits. The development of microbialites gives favorable ecological conditions to ostracods. During the Griesbachian, the fauna is composed of both new comers and surviving Palaeozoic forms. The reduction of size is frequently observed. This interval is called "survival stage". During the Dienerian and the Smithian the fauna are very scarce and poor. These two substages represent the maximum of poverty for the ostracod fauna, may be due to the development of anoxia on the platforms. During the Spathian, occurs the beginning of the true recovery. The very last Palaeozoic representatives are found in the Earliest Anisian which is the radiation stage of ostracod fauna with typical new comers. The interval of Palaeozoic-Meso-Cainozoic ostracod turnover is quite long (about 15My).

The sedimentary record of the Caspian Basin is an exceptional archive for the palaeoenvironmental, palaeoclimatic and biodiversity changes of continental Eurasia. During the Pliocene-Pleistocene, the Caspian Basin was mostly isolated but experienced large lake level fluctuations and short episodes of connection with the open ocean as well as the Black Sea Basin. A series of turnover events shaped a faunal record that forms the backbone of the Caspian geological time scale. The precise ages of these events are still highly debated, mostly due to the lack of well-dated sections. Here, we provide an integrated magneto-biostratigraphic age model for two sections from the Kura Basin – Goychay and Hajigabul. Our results reveal several major intervals with elevated salinity, associated with mesohaline faunas, and propose the following age constraints: 1) The Productive Series-Akchagylian boundary is marked by a marine transgression from the open ocean that occurred around the Gauss-Matuyama reversal (∼2.7–2.6 Ma); 2) The Akchagylian-Apsheronian transition is characterized by a regression event and introduction of a new, “Pontocaspian” mollusc assemblage, dated within the Reunion subchron (∼2.13 Ma). The ostracod assemblages of the two sections do not show a major faunal turnover here; 3) The early Bakunian transgression occurs after the upper Apsheronian lowstand (0.85–0.83 Ma). We conclude that major transitions in the age-indicative mollusc groups sometimes occur at different time intervals (i.e. diachronic) and are highly depended on the local depositional environments. A high-resolution interdisciplinary approach on sections outside the Kura Basin is required to better understand the potential diachroneity of these turnover events in the entire Caspian Basin.

Late Holocene environmental conditions are reconstructed from a sedimentary core (LCTF2) retrieved from Laguna Carmen (53° 40′ 60″S, 68° 18′ 0″W, 29 m a.s.l.) in the Fuegian steppe, northern Tierra del Fuego, southern Argentina. The multiproxy study utilizes pollen/spores, algae, ostracods, palynofacies, Total Organic Carbon (TOC), carbonate content, and lithology. Findings show that grass communities developed over the landscape from 4200 to 1400 cal yr BP. After that, the plant communities fluctuated between grasses to scrubland vegetation. Changes in the lake level as indicated by the halophytes, algal content and ostracod associations, revealed alternation of wet and dry intervals. The palynofacies indicate environments close to the terrestrial source with a great input of terrigenous organic matter into the lake in agreement with the sedimentary environment. By comparison with other sites from Tierra del Fuego and southwestern Patagonia, the record of wind-carried Nothofagus pollen is consistent with variations in the Andean forest communities as a consequence of shifts in the latitudinal position and/or strength of the westerlies. The short-term wet/dry intervals seem to be associated with climate events of local occurrence. On the other hand, some wet intervals have been reported in lacustrine records from southern Patagonia. The last millennium showed high environmental variability. Humid conditions characterized the Medieval Climate Anomaly (MCA) event, while dryness conditions were related to the Little Ice Age (LIA) event. In particular this latter interval has been related to a northward migration of the westerlies from their present day focus. Fil: Borromei, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; Argentina Fil: Candel, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego. Instituto de Ciencias Polares, Recursos Naturales y Ambiente; Argentina Fil: Musotto, Lorena Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; Argentina Fil: Cusminsky, Gabriela Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Martinez, Marcelo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; Argentina Fil: Coviaga, Corina Anabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Ponce, Juan Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego. Instituto de Ciencias Polares, Recursos Naturales y Ambiente; Argentina Fil: Coronato, Andrea Maria Josefa. Universidad Nacional de Tierra del Fuego. Instituto de Ciencias Polares, Recursos Naturales y Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina

In this study, we present complete descriptions and illustrations of nine ostracod species recovered from the Pozo D-129 Formation (Golfo San Jorge basin), Patagonia Argentina, discussing their depositional palaeoenvironment and palaeobiogeography. The species described in this study are Musacchiocythere sarugnata (Musacchio and Palamarczuk) and Metacypris herreriensis (Musacchio) (Family Limnocytheridae), Alicenula cf. leguminella (Forbes) (Family Darwinulidae), Neuquenocypris (Protoneuquenocypris) antiqua Musacchio and Simenoni, and Rhinocypris diademae Musacchio and Simenoni (Family Ilyocyprididae), Pattersoncypris cf. angulata (Krömmelbein and Weber) and Zonocypris sp. (Family Cyprididae), Damonella ultima (Krömmelbein and Weber) and Candona sp. (Family Candonidae). The Pozo D-129 Formation is the main source rock of hydrocarbons of the Golfo San Jorge basin, and its deposits represent an extensive lacustrine system. The samples studied come from the Cerro Chenques in the Sierra Silva anticline of the San Bernardo fold belt, Chubut Province, and from the well AAB.x-1002 (Anticlinal Aguada Bandera), Santa Cruz Province. The outcrop succession consists of several shallowing and coarsening upward sedimentary cycles 5–8 m thick, evolving from deep lacustrine, sublittoral and shallow lacustrine environments. The micropalaeontological association represents a moderate energy thanatocoenosis, and thus is a good indicator of the depositional palaeoenvironment. Taphonomic attributes and taxonomic composition of the association indicate deep and sublittoral environments, consistent with previous facies models for the outcrop succession, and suggest stressed water bodies. Previous studies of palynomorphs suggested a latest Barremian? to early Aptian Age for the study section, whilst the ostracod species Damonella ultima, and the charophytes Clavator harrisi Peck and Porochara ultima (Peck) are part of the Flabellochara [= Clavator] harrisi zone of Aptian Age. The ostracod fauna shows affinities to contemporaneous faunas of Brazil and West Africa, providing evidence of potential faunistic interchange between distant regions. Fil: Carignano, Ana Paula. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Paredes, José Matildo. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Olazábal, Sabrina Ximena. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Departamento de Geología; Argentina Fil: Valle, Mauro Nicolás. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Three hundred thirty-nine samples were collected from the Turonian-Coniacian succession that crops out in the Gafsa Basin and drilled in the Gulf of Gabes; these samples come from four outcrops and four wells and they were examined for their ostracod content. Sixty-two species belonging to twenty-nine genera were identified. They are subdivided into two major groups: smooth - species dominated assemblages and ornamented - species dominated assemblages. In the present work, five research goals are pursued: 1) to document the ostracod biodiversity encountered in the studied outcrops and wells, 2) to establish their biostratigraphic distribution, 3) to suggest a zonation mainly based on ostracods and correlated directly with the equivalent planktic foraminiferal zones, 4) to attempt a paleoenvironmental reconstruction based on the application of paleoecological characteristics of the identified ostracod assemblages. Finally, paleobiogeographical relationships were carried out between the Tunisian ostracods and those recorded in different regions of the Tethyan realm.

Thorough study of foraminifers, ostracods and dinoflagellate remnants from the Zavodskaya Balka and Koklyuk sections helps to characterize the detailed biostratigraphic division of the Berriasian / Valanginian boundary sequence in the Feodosiya district of eastern Crimea. The foraminifer and dinocyst associations from the lower part of the sequence are clearly comparable with common Berriasian associations throughout all Mountain Crimea. On the other hand, foraminifer, ostracod and dinocyst associations from its upper part have been recorded only in eastern Crimea. The upper foraminifer level corresponds to the boreal ammonite zones from the Tauricum-Verrucosum (Upper Berriasian-Valanginian). Most of the ostracod species are endemic. The base of the uppermost dinocyst level correlates with the Lower Valanginian Paratollia zone from north-western Europe.

A research was conducted on the Holocene lake sediments from the full-cored FA-1 drilling at the southern shore of the Qarun Lake in the Faiyum Oasis in northern Egypt. Altogether 10 taxa of molluscs and 8 taxa of ostracods were identified in the examined deposits, with total amounts of 768 and 2872 individuals, respectively. The fauna was investigated with palaeoecological purpose and allowed for preliminary reconstruction of sedimentary environment in the lake. The occurrence of Valvata nilotica Jickeli, 1874 and Gomphocythere sp. in the lower part of the core and a low proportion of carapaces (2.4-28%) indicated freshwater and higher-energy conditions, respectively. Rapid expansion of Cyprideis torosa (Jones, 1850) at a depth of 18 m could point to very short saline episode in the lake. The increase in salinity and drop of water level were evidenced in the uppermost part of the core (4-3.5 m), when the lake was dominated by Hydrobia ventrosa (Montagu, 1803), Cerastoderma glaucum (Poiret, 1789) and C. torosa. The steady sedimentation in a shallow lake was also supported by considerable amount of complete ostracod carapaces (45%). The faunal assemblage and smooth valves of C. torosa suggested salinity of 14-25‰.