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Orbital cyclicity is a fundamental pacemaker of Earth's climate system. The Newark-Hartford Basin (NHB) lake sediment record of eastern North America contains compelling geologic expressions of this cyclicity, reflecting variations of climatic conditions in tropical Pangea during the Late Triassic and earliest Jurassic (~233 to 199 Ma). Climate modeling enables a deeper mechanistic understanding of Earth system modulation during this unique greenhouse and supercontinent period. We link major features of the NHB record to the combined climatic effects of orbital forcing, paleogeographic changes, and atmospheric

Orbital cyclicity is a fundamental pacemaker of Earth’s climate system. The Newark–Hartford Basin (NHB) lake sediment record of eastern North America contains compelling geologic expressions of this cyclicity, reflecting variations of climatic conditions in tropical Pangea during the Late Triassic and earliest Jurassic (~233 to 199 Ma). Climate modeling enables a deeper mechanistic understanding of Earth system modulation during this unique greenhouse and supercontinent period. We link major features of the NHB record to the combined climatic effects of orbital forcing, paleogeographic changes, and atmospheric p CO 2 variations. An ensemble of transient, orbitally driven climate simulations is assessed for nine time slices, three atmospheric p CO 2 values, and two paleogeographic reconstructions. Climatic transitions from tropical humid to more seasonal and ultimately semiarid are associated with tectonic drift of the NHB from ~ 5 ° N to 20 ° N . The modeled orbital modulation of the precipitation–evaporation balance is most pronounced during the 220 to 200 Ma interval, whereas it is limited by weak seasonality and increasing aridity before and after this interval. Lower p CO 2 at around 205 Ma contributes to drier climates and could have led to the observed damping of sediment cyclicity. Eccentricity-modulated precession dominates the orbitally driven climate response in the NHB region. High obliquity further amplifies summer precipitation through the seasonal shifts in the tropical rainfall belt. Regions with other proxy records are also assessed, providing guidance toward an integrated picture of global astronomical climate forcing in the Late Triassic and ultimately of other periods in Earth history.

A review of short-term (

The Mesozoic era (∼252 to 66 million years ago) was a key interval in Earth's evolution toward its modern state, witnessing the breakup of the supercontinent Pangaea and significant biotic innovations like the early evolution of mammals. Plate tectonic dynamics drove a fundamental climatic transition from the early Mesozoic supercontinent toward the Late Cretaceous fragmented continental configuration. Here, key aspects of Mesozoic long‐term environmental changes are assessed in a climate model ensemble framework. We analyze so far the most extended ensemble of equilibrium climate states simulated for evolving Mesozoic boundary conditions covering the period from 255 to 60 Ma in 5 Myr timesteps. Global mean temperatures are generally found to be elevated above the present and exhibit a baseline warming trend driven by rising sea levels and increasing solar luminosity. Warm (Triassic and mid‐Cretaceous) and cool (Jurassic and end‐Cretaceous) anomalies result from pCO2 changes indicated by different reconstructions. Seasonal and zonal temperature contrasts as well as continental aridity show an overall decrease from the Late Triassic‐Early Jurassic to the Late Cretaceous. Meridional temperature gradients are reduced at higher global temperatures and less land area in the high latitudes. With systematic sensitivity experiments, the influence of paleogeography, sea level, vegetation patterns, pCO2, solar luminosity, and orbital configuration on these trends is investigated. For example, long‐term seasonality trends are driven by paleogeography, but orbital cycles could have had similar‐scale effects on shorter timescales. Global mean temperatures, continental humidity, and meridional temperature gradients are, however, also strongly affected by pCO2., Key Points We assess global long‐term climate trends through the Mesozoic era with an ensemble of climate model simulationsVarying carbon dioxide levels cause anomalies around an overall warming trend due to changing paleogeography and increasing insolationSeasonal and zonal temperature contrasts as well as aridity decrease with time, while meridional gradients vary with paleogeography

The Luanping Basin of northern Hebei, North China, is well known for its continuous nonmarine Lower Cretaceous deposits and the preservation of the Jehol Biota. However, there are still some controversies about the stratigraphic correlation in these regions. Here we report some advances on the study of the nonmarine ostracods of Luanping, focusing on its biostratigraphical utility. Preliminary results indicate that the nonmarine ostracods from Luanping Basin consist of 17 genera and around 44 species. The ostracod assemblages of the Dabeigou, Dadianzi and Xiguayuan formations of this Basin can be assigned to the Luanpingella-Ocrocypris-Eoparacypris (Late Valanginian-Early Hauterivian age), Cypridea-Timiriasevia-Daurina (Late Huaterivian-Barremian age) and Cypridea-Limnocypridea-Lycopterocypris (Aptian stage) zones, respectively. This temporary framework can be served as a stratigraphic correlation tool in northern Hebei, as well as contributed to a better understanding of the evolution of the Jehol Biota.

The Upper Cretaceous Postalm section in the Northern Calcareous Alps (Austria) exposes pelagic deposits of the northwestern Tethys whose cyclostratigraphy and palaeoenvironments were examined in this study. The section displays rhythmic deposits of Santonian to late Campanian age (Gosau Group). The Santonian/Campanian transition is characterised by condensed greyish carbonates, while the younger deposits are composed of reddish foraminiferal packstones displaying distinct limestone-marl alternations. A biostratigraphic framework based on planktonic foraminifera and calcareous nannofossils is supported by carbon and strontium isotope stratigraphy as well as magnetostratigraphy. The carbon isotope data allow to correlate the Postalm section to other Tethyan reference sites and to identify δ13C events, such as the Late Campanian Event. Spectral analyses of three independently assessed proxies (δ13C, Fe content and the thickness of limestone/marl couplets) in the upper, continuously exposed section part identified 17 to 18 405 ka cycles spanning the mid to upper Campanian (Contusotruncana plummerae to Gansserina gansseri Zones or CC21/UC15c to CC23a/UC16 nannofossil zones).

The Turonian–Coniacian continental fossil record in Europe is scarce. Here we present a new fossil assemblage of early Coniacian age that was systematically collected from the coal-bearing Gosau Group of the Tiefengraben locality near St. Wolfgang, Austria. The diverse assemblage is composed of at least 60 taxa including sporomorphs and Normapolles-related pollen, seeds and leaves of angiosperms and gymnosperms, charophytes, gastropods, bivalves, ostracods, termites, fishes, crocodiles and dinosaurs. Concerning charophytes, ostracods, gastropods, crocodiles and dinosaurs, the discovered specimens either extend the temporal and spatial range of specific groups (in some cases as possible relict forms) or suggest the occurrence of new taxa. The discovered remains of algae, molluscs, ostracods, calcareous nannofossils and lepisosteid fish represent a mixed faunal assemblage from different palaeohabitats, from marginal marine to low salinity and freshwater or terrestrial environments. As Normapolles-related angiosperm plants dominate the flora with a relatively high number of dentate leaves, a slightly cooler microenvironment compared to other Turonian–Coniacian Central European localities is indicated. The characteristically grooved crocodylian teeth of Tiefengraben differ from the previously known Upper Cretaceous European crocodyliform teeth and suggest a more diverse crocodyliform fauna in the region. Dinosaurs are represented by teeth of at least three different theropods, the largest of which is referred here to as basal tetanurans. The fossil assemblage of this early Gosau Group occurrence is of great importance for our understanding of the continental floristic and faunistic composition of the western Tethyan archipelago during the Cenomanian–Campanian gap.

A diverse Eocene charophyte flora from a section at G ant (V ertes Hills), Transdanubian Central Range, north-western Hungary, provides significant new information building on previous studies based only on sub-surface data published from the mid-twentieth century. This newly acquired material facilitates the taxonomic revision and emendation of the species Raskyella peckii and thereby defines a new anagenetic lineage based on three successive varieties that were formerly considered as separate species or subspecies: Raskyella peckii var. peckii (early Lutetian-early Bartonian), Raskyella peckii var. caliciformis (early Bartonian), and Raskyella peckii var. vadaszii (late Bartonian). Based on this lineage, we propose a new local charophyte biozonation that consists of a 'Raskyella peckii Superzone' (Lutetian-Bartonian), sub-divided into three successive charophyte partial range zones: the 'Raskyella peckii peckii Zone' Lutetian-lower-most Bartonian) characterized by an assemblage of R. peckii peckii, Gyrogona caelata forma caelata, G. caelata forma monolifera and Nitellopsis (Tectochara) aff. palaeohungarica, the 'Raskyella peckii caliciformis Zone' (lower Bartonian) characterized by the assemblage of R. peckii var. caliciformis, G. caelata forma caelata, G. caelata forma monolifera, G. caelata forma baccata, Nitellopsis (Tectochara) aff. palaeohungarica and Chara media, and the 'Raskyella peckii vadaszii Zone' (upper Bartonian) characterized by R. peckii var. vadaszii, G. caelata forma bicincta, G. caelata forma baccata, G. caelata forma fasciata, G. tuberosa, Psilochara polita, Psilochara sp., Chara media and Chara subcylindrica. Future research may show the new local biozonation as applicable to the whole of Europe and complementary to the current European charophyte biozonation. Our results show that the sequences from Gant, which were previously regarded as upper mid-Eocene (upper Lutetian-lower Bartonian) in age, appear to represent a longer chronostratigraphic interval: lower Lutetian to upper Bartonian. Our chronostratigraphic results imply a longer and more stepwise Eocene major transgression in the Transdanubian Central Range than previously thought.

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.

The celebrated fossil locality of Tendaguru (Tanzania, East Africa) has been well known for its unique Late Jurassic dinosaur assemblages since the early decades of the 20th century. Recently, within the scope of the German-Tanzanian Tendaguru project, an expedition returned to Tendaguru with the aim of collecting microvertebrates, micro- and macroinvertebrates, plant fossils and new sedimentological and stratigraphical data. Applying a multidisciplinary research approach, the data collected were used to address various controversial issues regarding the Tendaguru Beds. These include their exact age, depositional environments and reconstructions of the palaeoecosystems in which the dinosaurs lived. Field work resulted in a new standard section for the Tendaguru Beds. Preliminary biostratigraphic results, based on ammonites, charophytes and palynomorphs, support a Late Kimmeridgian age for the Nerinea Bed, an early Tithonian age for the Trigonia smeei Bed, and an Early Cretaceous (possibly Valanginian to Hauterivian) age for the Trigonia schwarzi Bed. Facies analysis of the Tendaguru Beds indicates environments ranging from storm- and tide-influenced, siliciclastic coastal barrier systems, ooid sand bar complexes and backbarrier tidal flats to sabkha-like coastal plains with brackish lakes and pools. Sedimentological indicators of palaeoclimate and palynological data point to a subtropical to tropical climate with pronounced dry seasons. In concert with sedimentological data, quantitative palaeoecological analysis of macroinvertebrates helped to finetune understanding of environmental factors such as substrate conditions, salinity, sedimentation rate and water depth. Along with abundant microvertebrate remains and fragments of fusain and cuticles, these new data have considerably improved our knowledge of the fauna and flora found in the Tendaguru Beds, and provide a solid basis for developing a better understanding of the Late Jurassic and Early Cretaceous Tendaguru palaeoecosystems. To put the German-Tanzanian Tendaguru expedition in perspective, a brief review of previous activities is given and future research objectives are outlined. Die berühmte Fossilfundstätte Tendaguru (Tansania, Ostafrika) ist seit Anfang des 20. Jahrhunderts weltweit für ihre Dinosaurier aus der späten Jura-Zeit bekannt. Im Rahmen des Deutsch-Tansanischen Tendaguru Projekts fand im August und September 2000 eine Expedition in die Umgebung des Tendaguru-Hügels statt. Ziel der Expedition war es, umfangreiche Fossilaufsammlungen von Mikrovertebraten, Mikro- und Makroinvertebraten und pflanzlichen Fossilien durchzuführen und neue sedimentologische und stratigraphische Daten aufzunehmen. Unter Anwendung eines interdisziplinären Forschungsansatzes wurden mit den gesammelten Daten verschiedene, bisher kontrovers diskutierte Aspekte der Tendaguru-Schichten untersucht. Offene Fragen umfassten die genaue Alterseinstufung, eine Interpretation der Ablagerungsräume und die Rekonstruktion der Paläoökosysteme, in denen die Dinosaurier lebten. Die erste Auswertung der Geländedaten führte zu einem neuen Standardprofil für die Tendaguru-Schichten. Vorläufige biostratigraphische Ergebnisse, die auf Ammoniten, Charophyten und Palynomorphen basieren, sprechen für ein Ober-Kimmeridgium Alter der Nerineen Schicht, Unteres Tithonium für die Trigonia smeei Schicht und Untere Kreide (möglicherweise Valanginium bis Hauterivium) für die Trigonia schwarzi Schicht. Die Lebens- und Ablagerungsräume der Tendaguru-Schichten reichten von sturm- und gezeitenbeeinflussten, küstennahen, siliziklastischen Barrieresystemen und Kalkooid-Barren über ausgedehnte Wattflächen bis zu sabkha-artigen Küstenebenen mit brackischen Seen und Tümpeln. Sedimentologische Anzeiger des Paläoklimas und palynologische Daten sprechen für ein subtropisches bis tropisches Klima mit ausgeprägten Trockenzeiten. Im Verbund mit sedimentologischen Daten ermöglicht die quantitative paläoökologische Analyse der Makroinvertebraten eine genauere Charakterisierung wichtiger physikalischer Umweltparameter wie Substrateigenschaften. Salinität. Sedimentationsrate und Bathymetrie. Zusammen mit den häufig vorkommenden Mikrovertebraten und Bruchstücken von Fusit und Cuticulen haben diese neu gewonnenen Daten die Kenntnisse über die Faunen und Floren der Tendaguru-Schichten erheblich erweitert und liefern die Basis für ein besseres Verständnis der in den Ablagerungen dokumentierten Ökosysteme aus Jura- und Kreidezeit. Neben einem kurzen Abriss der Forschungsgeschichte werden die für die Zukunft geplanten Forschungsaktivitäten dargestellt. doi:10.1002/mmng.20010040113

The Late Jurassic to Early Cretaceous Tendaguru Beds (Tanzania, East Africa) have been well known for nearly a century for their diverse dinosaur assemblages. Here, we present sedimentological and palaeontological data collected by the German-Tanzanian Tendaguru Expedition 2000 in an attempt to reconstruct the palaeo-ecosystems of the Tendaguru Beds at their type locality. Our reconstructions are based on sedimentological data and on a palaeoecological analysis of macroinvertebrates, microvertebrates, plant fossils and microfossils (ostracods, foraminifera, charophytes, palynomorphs). In addition, we included data from previous expeditions, particularly those on the dinosaur assemblages. The environmental model of the Tendaguru Beds presented herein comprises three broad palaeoenvironmental units in a marginal marine setting: (1) Lagoon-like, shallow marine environments above fair weather wave base and with evidence of tides and storms. These formed behind barriers such as ooid bar and siliciclastic sand bar complexes and were generally subject to minor salinity fluctuations. (2) Extended tidal flats and low-relief coastal plains. These include low-energy, brackish coastal lakes and ponds as well as pools and small fluvial channels of coastal plains in which the large dinosaurs were buried. Since these environments apparently were, at best, poorly vegetated, the main feeding grounds of giant sauropods must have been elsewhere. Presumably, tidal flats and coastal plains were visited by dinosaurs primarily during periods of drought. (3) Vegetated hinterland. Vegetation of this environment can only be inferred indirectly from plant material transported into the other depositional environments. Vegetation was dominated by a diverse conifer flora, which apparently formed part of the food source of large herbivorous sauropods. Evidence from various sources suggests a subtropical to tropical palaeoclimate, characterised by seasonal rainfall alternating with a pronounced dry season during the Late Jurassic. In Early Cretaceous times, sedimentological and palaeontological proxies suggest a climatic shift towards more humid conditions. Die Tendaguru-Schichten von Tansania in Ostafrika (Oberjura bis Unterkreide) sind als Lagerstätte oberjurassischer Dinosaurier seit nahezu einem Jahrhundert weltweit bekannt. Anhand von sedimentologischen und paläontologischen Daten, die während der Deutsch-Tansanischen Tendaguru Expedition 2000 im Typus-Gebiet der Tendaguru-Schichten gewonnen wurden, werden Paläo-Ökosysteme rekonstruiert. Grundlage der Rekonstruktionen sind die Auswertung sedimentologischer Daten sowie die paläo-ökologische Analyse von Makroinvertebraten, Mikrovertebraten, pflanzlichen Fossilien und Mikrofossilien (Ostrakoden, Foraminiferen, Charophyten, Palynomorphen). Darüber hinaus werden Informationen über Dinosaurier berücksichtigt, die bei früheren Expeditionen gewonnen wurden. Das hier vorgestellte Ablagerungsmodell der Tendaguru-Schichten umfaßt drei Teilbereiche eines randlich marinen Sedimentationsraumes, die wie folgt gekennzeichnet werden können: (1) Lagunen-artige, marine Flachwasserbereiche, die oberhalb der Schönwetter-Wellenbasis lagen und unter deutlichem Einfluß von Gezeiten und Stürmen standen. Sie waren vom offenen Meer durch Barrieren, wie Ooidbarren und siliziklastischen Sandbarrenkomplexen, getrennt und wiesen einen leicht schwankenden Salzgehalt auf. (2) Ausgedehnte Wattgebiete und flache Küstenebenen. Dort befanden sich niedrig-energetische, brackische Strandseen und Teiche sowie Tümpel und kleinere Flußrinnen, in denen die großen Dinosaurier eingebettet wurden. Da diese Lebensräume bestenfalls dürftig bewachsen waren, müssen die Nahrungsquellen und der eigentliche Lebensraum der riesigen Sauropoden anderswo gelegen haben. Vermutlich wurden die Wattgebiete und Flachküsten von Dinosauriern vorrangig in den Trockenzeiten aufgesucht. (3) Bewachsenes Hinterland. Die Vegetation dieses Lebensraumes kann nur indirekt aus Pflanzenresten erschlossen werden, die in die anderen Ablagerungsraume transportiert wurden. Die Vegetation wurde von einer diversen Koniferenflora dominiert, die zumindest teilweise die Nahrungsgrundlage der großen, herbivoren Sauropoden bildete. Sedimentologische und paläontologische Indikatoren sprechen für ein subtropisches bis tropisches Klima wahrend der späten Jurazeit mit einem jahreszeitlichen Wechsel von Regenfällen und ausgeprägten Trockenzeiten. In der frühen Kreidezeit deutet sich ein Wechsel zu starker humiden Bedingungen an. doi:10.1002/mmng.20020050103

Reference list.

The revision of Theriosynoecum Branson 1936, a common ostracod genus of Middle Jurassic to Early Cretaceous nonmarine deposits worldwide, demonstrates that its representatives–particularly the Early Cretaceous North American ones–are not as endemic as hitherto assumed. The taxonomic concept applied herein resolves many problems resulting from an overestimation of the taxonomic (in-)significance of some ornamentation elements in the genus as well as the too regional view of the faunas during the second half of the 20th century. This is the first step to a supraregional biostratigraphic and improved paleoecologic application of representatives of the extinct genus Theriosynoecum (Cytheroidea, Limnocytheridae, Timiriaseviinae). Theriosynoecum fittoni (Mantell 1844) and Theriosynoecum alleni (Pinto and Sanguinetti 1962) are proposed for being synonymous because of their many striking similarities. The species Theriosynoecum forbesii (Jones 1885) and T. verrucosa (Jones 1885) are considered separate and not subspecies of T. forbesii. Theriosynoecum verrucosa occurs in the uppermost Morrison Formation of the Black Hills area, South Dakota, U.S.A., Theriosynoecum fittoni in the Lakota Formation of the same area. Theriosynoecum pahasapensis (Roth 1933) is, thus far, endemic to North America. A key to the described species is presented. Early Cretaceous species of Theriosynoecum are not yet as applicable biostratigraphically in North America as in Europe (e.g. the English Purbeck/Wealden), but this is due to the lack of data from the former area and considered to be promising once more data are available. Nevertheless, the "classic" taxonomic approach provides a considerable step towards better application of these taxa as well as future analysis and robust discussion regarding the phylogeny, evolution and distribution of the limnocytherid subfamily Timiriaseviinae. The genus Metacypris is now restricted to an Aptian to recent lineage of small, weakly monosulcate Timiriaseviinae. Middle Jurassic to Early Cretaceous bisulcate and large taxa formerly designated as Metacypris are now assigned to Theriosynoecum.

Despite the fact that the number of publications on the morphologic terms of ostracod carapace features is impressive, definitions, use and interpretation of many terms remain inconsistent and therefore fraught with problems. A particular problem is the application of certain terms of morphologic features in different ostracod groups without the consideration of their potentially different origin, genesis and nature. This revised and annotated glossary focuses on nonmarine ostracods, families Timiriaseviinae (Cytheroidea, Limnocytheridae) and Cyprideidae (extinct, Cypridoidea), particularly on the extinct genera Theriosynoecum and Cypridea in its selection of terms and given examples, and is strongly connected with the preceding papers of this issue (Sames 2011a, b) which also include the supporting illustrations. It as well comprises detailed discussions on the origin and differentiation of the taxonomic or otherwise significance of selected carapace features, particularly ornamentation. Herein, ornamentation is subdivided into area-wide and local ornamentation elements for that reason. In contrast to their patterns of distribution, the presence of local ornamentation elements as well as their degree of expression are considered of no, or rather low, taxonomic significance. If applicable, local ornamentation elements can be used for paleoenvironmental interpretations or to identify juveniles in some cases (e.g. in Cypridea). Type, occurrence and shape of area-wide ornamentation elements are, by contrast, always taxonomically relevant to a certain degree. As to the Family Cyprideidae, the alveolar ridge is newly introduced and defined, and the terms for the anteroventral (alveolus and its elements) and posteroventral regions (cyathus, cyathus-like protrusion) are redefined and discussed. A morphologic term can never be a matter of common or collective knowledge as long as its appreciation and usage differs between researchers. In fact, the accuracy of its usage can only be identified when we know that we are talking about the same thing. With this glossary it is intended to better communicate the views of the author, to integrate new insights into ostracod paleobiology into the interpretation of carapace features, and to propose a kind of harmonization between different concepts as well as to put these up for discussion and further development.

Cypridea Bosquet 1852 (Cypridoidea, Cyprideidae) is a Kimmeridgian to Lower Eocene nonmarine ostracod genus, the representatives of which are very common and stratigraphically useful in Late Tithonian to earliest Barremian "Purbeck/Wealden-like" nonmarine deposits of the world. The revision of particularly North American representatives led to progress in its taxonomy, and a breakthrough in its biostratigraphic supraregional biostratigraphic application. Key to their successful application is an upgraded taxonomic concept including new insights into the coherences of specific reproductive mechanisms (asexual and mixed reproduction) in the context with diversity and dispersal modes, combined with the understanding and evidence that these ostracods are not as endemic as erstwhile believed. This taxonomic concept resolves crucial problems resulting from an overestimation of the taxonomic significance of several carapace characters (particularly ornamentation elements and the outline), and facilitates improved stratigraphic and paleoecologic applications as well as providing the basis for further research. The revision includes an extensive historic overview of most relevant publications. Representatives of Cypridea have great utility in improving the biostratigraphic age determination for and correlation of Early Cretaceous formations of the Western Interior foreland basin. With respect to suprageneric taxonomy, the family Cyprideidae Martin 1940 is partially revised as well. Longispinella Sohn 1979 is now considered a subgenus of Cypridea while Cypridea (Guangdongia) Guan 1978 is allocated to Bisulcocypridea Sohn 1969, and the genus Praecypridea Sames, Whatley and Schudack 2010(b) is included. The genus Cypridea is emended anew. As for the subgeneric taxonomy, the North American species Cypridea (Pseudocypridina) inornata (Peck 1951) is now considered a junior synonym of Cypridea (P.) setina (Anderson 1939), Cypridea (P.) laeli Sohn 1979 considered an ecophenotype of Cypridea (P.) piedmonti (Roth 1933), and Cypridea (Longispinella) asymmetrica Sohn 1979 designated synonymous (sexual dimorph) to C. (L.) longispina Peck 1941. Sexual dimorphism is presumed in several species of Cypridea and mixed reproduction corroborated as being the most likely reproductive mechanism among taxa of this genus. Cypridea? minuta (Peck 1951) most probably represents an early representative of the sulcate Bisulcocypridea Sohn. Ostracod correlations mainly based on representatives of Cypridea strongly suggest a much higher maximum age for some Lower Cretaceous formations (Lakota Formation, South Dakota and Wyoming, and Cedar Mountain Formation, Utah) of the Western Interior foreland basin, i.e., Berriasian to Early Valanginian instead of Barremian or Aptian.

The genus Praecypridea gen. nov. (Cypridoidea, Family Cyprideidae Martin, 1940) is described and thus far comprises four species: the type species Praecypridea acuticyatha (Schudack, 1998) comb. nov., Praecypridea postelongata (Oertli, 1957) comb. nov., Praecypridea suprajurassica (Mojon, Haddoumi & Charriére, 2009) comb. nov. and Praecypridea acuta (Moos, 1959 in Wicher, 1959) comb. nov. Representatives of the new genus have been described from the Middle to Late Jurassic of Europe, North America and Africa and the Early Cretaceous of South America, with other presumed representatives also occurring in the Early Cretaceous. Species of Praecypridea are considered to represent members of the ancestral lineage of the extinct genus Cypridea Bosquet, representatives of which flourished in non-marine habitats of latest Jurassic to Early Cretaceous age and account for the first period of abundance of the non-marine Cypridoidea.

The 1st International Symposium on Ostracoda (ISO) was held in Naples (1963). The philosophy behind this symposium and the logical outcome of what is now known as the International Research Group on Ostracoda (IRGO) are here reviewed, namely ostracodology over the last 50 years is sociologically analysed. Three different and important historic moments for the scientific achievements of this domain are recognised. The first one, between about 1963 and 1983, is related to applied research for the oil industry as well as to the great interest in the better description of the marine environment by both zoologists and palaeontologists. Another important aspect during this period was the work by researchers dealing with Palaeozoic ostracods, who had their own discussion group, IRGPO. Gradually, the merger of this latter group with those dealing with post-Palaeozoic ostracods at various meetings improved the communication between the two groups of specialists. A second period was approximately delineated between 1983 and 2003. During this time-slice, more emphasis was addressed to environmental research with topics such as the study of global events and long-term climate change. Ostracodologists profited also from the research “politics” within national and international programmes. Large international research teams emerged using new research methods. During the third period (2003–2013), communication and collaborative research reached a global dimension. Amongst the topics of research we cite the reconstruction of palaeoclimate using transfer functions, the building of large datasets of ostracod distributions for regional and intercontinental studies, and the implementation of actions that should lead to taxonomic harmonisation. Projects within which molecular biological techniques are routinely used, combined with sophisticated morphological information, expanded now in their importance. The documentation of the ostracod description improved through new techniques to visualise morphological details, which stimulated also communication between ostracodologists. Efforts of making available ostracod information through newsletters and electronic media are evoked.

Mammalian diversity in North America shifted significantly during the Early Cretaceous, from archaic groups dominant in the well-sampled faunas of the Late Jurassic to advanced forms (including early members of modern clades) by the Albian—Cenomanian. However, the dynamics of this transition are poorly understood, since faunas of earliest Cretaceous age are unknown. Here we describe the first fossil mammals from exposures of the Lakota Formation in the Black Hills of South Dakota, a unit correlated with the upper Berriasian—lower Barremian and positioned stratigraphically between the underlying Morrison Formation and Aptian—Albian units exposed elsewhere in North America. The mammalian fauna from the Lakota Formation is transitional with regard to the North American fossil record, representing a broad spectrum of both Jurassic and Cretaceous lineages: present are “plagiaulacidan” multituberculates allied with Late Jurassic Allodontoidea and Early Cretaceous Plagiaulacoidea; the geologically youngest dryol...

On several occasions at paleontology-, geology-, and stratigraphy-related meetings during the past years, I noticed that many colleagues, even micropaleontologists, are not (anymore!) aware of the fundamental application potential of pre-Quaternary, fresh- and brackish-water ostracode fossils. Ostracodes, aquatic crawling or swimming microcrustaceans with a calcified bivalved shell and high fossilization potential, have rarely been considered as a major tool in biostratigraphy, fading mostly into the background compared to other fossil groups in the marine realm. In the continental realm, however, ostracodes are often the most common and abundant fossils, whether in freshwater or saline deposits. Yet, supraregional and intercontinental biostratigraphy based on aquatic organisms sounds absurd. It is not, however! Fresh- and brackish-water ostracodes have developed different strategies and mechanisms to facilitate their adaptation to temporary habitats and dispersal in such settings. Recent fresh- and brackish-water ostracodes, just as did their fossil counterparts, have a high potential to be passively distributed over long distances and across migration barriers by wind and larger animals, particularly owing to the desiccation- and freeze-resistant resting eggs of major groups (e.g., Horne and Martens, 1998) and, therefore, are a strong candidate for biostratigraphic application. Dealing with biostratigraphy of Lower Cretaceous continental deposits, it is important to understand that in most regions, except western Europe, we are not necessarily talking about high-resolution biostratigraphy. For example, many publications to-date on such deposits in Central Asia, South America, and Africa only provide an age of Early Cretaceous without further subdivision, and no attribution to stages. In the North American Western Interior foreland basin, Lower Cretaceous continental deposits are widely regarded to be of pre-middle Albian age, or to range from Aptian to Albian, sometimes Barremian–Albian in age (e.g., Cobban and Reeside, 1952; Peck, 1959; Mateer et al., 1992; Dyman et al. 1994; Way et …

Introductory Note