Upper Aptian–albian Rudist Bivalves from Northern Sinai, Egypt

Rudist bivalves are described from two Upper Aptian–Albian sections in northern Sinai, Egypt. Independent stratigraphical evidence is provided by orbitolinid foraminifera and sequence stratigraphic correlation with other, ammonite–bearing sections of the region. With the exception of Eoradiolites liratus (Conrad) and Sellaea, this is the first record of Lower Cretaceous rudists from Egypt. A rather continuous occurrence of rudists is recorded in the more open marine deposit at Rizan Aneiza, but they occur only in the Middle–Upper Albian at Gebel Raghawi to the south–west. In the uppermost Aptian to basal Middle Albian at Rizan Aneiza, the succession of Eoradiolites plicatus–E. murgensis–E. liratus is interpreted as a lineage of chronospecies. Of particular interest is the presence of canaliculate rudists in the Upper Albian of both sections, as there exists a large gap, spanning the Upper Aptian and most parts of the Albian, in the fossil record of the Caprininae d’Orbigny. Neocaprina raghawiensis sp. nov. and Neocaprina? sp. are recognized as ancestors of Cenomanian species of Neocaprina Pleni?ar and Caprinula d’Orbigny. The inclusion of these genera in the Caprininae d’Orbigny is questioned and the phylogenetic descent from an unidentified Albian taxon with well–developed myophoral cavities is suggested.     

Coral-rudist bioconstructions in the Upper Cretaceous Haidach section (Gosau Group; Northern Calcareous Alps, Austria)

Summary In the area of Haidach (Northern Calcareous Alps, Austria), coral-rudist mounds, rudist biostromes, and bioclastic limestones and marls constitute an Upper Cretaceous shelf succession approximately 100 meters thick. The succession is part of the mixed siliciclasticcarbonate Gosau Group that was deposited at the northern margin of the Austroalpine microplate. In its lower part, the carbonate succession at Haidach comprises two stratal packages that each consists, from bottom to top, of a coral-rudist mound capped by a rudist biostrome which, in turn, is overlain by bioclastic limestones and, locally, marls. The coral-rudist mounds consist mainly of floatstones. The coral assemblage is dominated by Fungiina, Astreoina, Heterocoeniina andAgathelia asperella (stylinina). From the rudists, elevators (Vaccinites spp., radiolitids) and recumbents (Plagioptychus) are present. Calcareous sponges, sclerosponges, and octocorals are subordinate. The elevator rudists commonly are small; they settled on branched corals, coral heads, on rudists, and on biolastic debris. The rudists, in turn, provided settlement sites for corals. Predominantly plocoid and thamnasteroid coral growth forms indicate soft substrata and high sedimentation rates. The mounds were episodically smothered by carbonate mud. Many corals and rudists are coated by thick and diverse encrustations that indicate high nutrient level and/or turbid waters. The coral-rudist mounds are capped byVaccinites biostromes up to 5 m thick. The establishment of these biostromes may result from unfavourable environmental conditions for corals, coupled with the potential of the elevator rudists for effective substrate colonization. TheVaccinites biostromes are locally topped by a thin radiolitid biostrome. The biostromes, in turn, are overlain by bioclastic limestones; these are arranged in stratal packages that were deposited from carbonate sand bodies. Approximately midsection, an interval of marls with abundantPhelopteria is present. These marls were deposited in a quiet lagoonal area where meadows of sea grass or algae, coupled with an elevated nutrient level, triggered the mass occurrence ofPhelopteria. The upper part of the Haidach section consists of stratal packages that each is composed of a rudist biostrome overlain by bioclastic wackestones to packstones with diverse smaller benthic foraminifera and calcareous green algae. The biostromes are either built by radiolitids,Vaccinites, andPleurocora, or consist exclusively of radiolitids (mainlyRadiolites). Both the biostromes and the bioclastic limestones were deposited in a low-energy lagoonal environment that was punctuated by high-energy events.In situ-rudist fabrics typically have a matrix of mudstone to rudistclastic wackestone; other biogens (incl. smaller benthic foraminifera) are absent or very rare. The matrix of rudist fabrics that indicate episodic destruction by high-energy events contain a fossil assemblage similar to the vertically associated bioclastic limestones. Substrata colonized by rudists thus were unfavourable at least for smaller benthic foraminifera. The described succession was deposited on a gently inclined shelf segment, where coral-rudist mounds and hippuritid biostromes were separated by a belt of bioclastic sand bodies from a lagoon with radiolitid biostromes. The mounds document that corals and Late Cretaceous elevator rudists may co-occur in close association. On the scale of the entire succession, however, mainly as a result of the wide ecologic range of the rudists relative to corals, the coral-dominated mounds and the rudist biostromes are vertically separated.     

Cenomanian–Early Turonian Ostracoda of the shallow marine carbonate platform sequence at west central Sinai: Biostratigraphy,paleobathymetry and paleobiogeography

The Cenomanian–Lower Turonian succession exposed in west central Sinai is carefully studied for their ostracode content. The Raha and Abu Qada Formations were studied in 4 sections. Their ostracode content includes the recognition of 70 species belonging to 34 genera. One species is considered as new (Spinoleberis grosdidieri n. sp.). The vertical distribution of the ostracodes in the sections enables the detection of four local biostratigraphic zones with a Barren Interzone in between. In terms of paleobathymetry, each studied sequence reveals deposition on a shallow reefal carbonate platform of less than 100 m depth. The flourishing of cytherellids in repeated intervals refers to kenoxic events within the Cenomanian section. These events are enhanced just below the Cenomanian–Turonian boundary referring to the Oceanic Anoxic Event 2. The wide paleobiogeographic distribution of the recorded Cenomanian ostracodes reveals that there was a direct connection throughout the Southern Tethyan Realm countries. Also, there was a migration path between the Southern Tethyan bioprovince and the West African bioprovince during the Cenomanian via the Trans-Saharan Seaway and along the Atlantic coast of West Africa.     

Biostratigraphy and Paleobiogeographic implications of the Cenomanian–Early Turonian Ostracods of Egypt

The present study deals with the Cenomanian–early Turonian ostracods in the southern Sinai, Egypt. The investigated sequence includes the Raha and Abu Qada formations. The Raha Formation consists of distinctive Cenomanian taxa such as Cytherella aegyptiensis, Veeniacythereis maghrebensis, V. jezzineensis, V. streblolophata streblolophata, Monoceratina trituberculata, and Glenocythere reticulata. Based on the ostracod species, four local biozones are recognized, including Veeniacythereis jezzineensis – Metacythereopteron berbericum, Cytherella eosulcata – Xestoleberis derorimensis, Amphicytherura ziregensis and Perissocytheridea istriana – Cythereis fahrioni. The paleobiogeography of the considered ostracods suggests that there are two bioprovinces, the first of which is the North African province and includes Egypt, Tunisia and Algeria. The second bioprovince represents the Middle East province and includes Lebanon, Oman and Iran. The strong resemblance between the two bioprovince indicates a relatively good communication along the margin of Southern Tethys during the Cenomanian and improved marine ostracod exchange.     

Late Cenomanian–Early Turonian facies development and sea-level changes in the Bodenwöhrer Senke (Danubian Cretaceous Group, Bavaria, Germany)

The Upper Cenomanian–Lower Turonian litho-stratigraphic units of the Danubian Cretaceous Group of the proximal Bodenwöhrer Senke (Regensburg, Eibrunn and Winzerberg formations, the latter consisting of a lower Reinhausen Member and an upper Knollensand Member), have been investigated with a focus on facies analysis and sequence stratigraphy. Analyses of litho-, bio-, and microfacies resulted in the recognition of 12 predominantly marine facies types for the Eibrunn and Winzerberg formations. Petrographic and paleontological properties as well as gradual transitions in the sections suggest that their depositional environment was a texturally graded, predominantly siliciclastic, storm-dominated shelf. The muddy–siliceous facies types FT 1–3 have been deposited below the storm wave-base in an outer shelf setting. Mid-shelf deposits are represented by fine- to medium-grained, bioturbated, partly glauconitic sandstones (FT 4–6). Coarse-grained, gravelly and/or shell-bearing sandstones (FT 7–10) developed in the inner shelf zone. Highly immature, arkosic coarse-grained sandstones and conglomerates (FT 11 and 12) characterize an incised, high-gradient braided river system. The Winzerberg Formation with its general coarsening- and thickening-upward trend reflects a regressive cycle culminating in a subaerial unconformity associated with a coarse-grained, gravelly unit of marine to fluvial origin known as the “Hornsand” which is demonstrably diachronous. The overlying Altenkreith Member of the Roding Formation signifies the onset of a new transgressive cycle in the early Middle Turonian. The sequence stratigraphic analysis suggests that the deposition of the Upper Cenomanian and Lower Turonian strata of the Bodenwöhrer Senke took place in a single cycle of third-order eustatic sea-level change between the major sequence boundaries SB Ce 5 (mid-Late Cenomanian) and SB Tu 1 (Early–Middle Turonian boundary interval). The southeastern part of the Bodenwöhrer Senke was flooded in the mid-Late Cenomanian (Praeactinocamax plenus transgression) and a second transgressive event occurred in the earliest Turonian. In the central and northwestern parts of the Bodenwöhrer Senke, however, the initial transgression occurred during the earliest Turonian, related to pre-transgression topography. Thus, the Regensburg and Eibrunn formations are increasingly condensed here and cannot be separated anymore. Following an earliest Turonian maximum flooding, the Lower Turonian Winzerberg Formation filled the available accommodation space, explaining its constant thickness of 35–40 m across the Bodenwöhrer Senke and excluding tectonic activity during this interval. Rapid sea-level fall at SB Tu 1 terminated this depositional sequence. This study shows that Late Cenomanian–Early Turonian deposition in the Bodenwöhrer Senke was governed by eustatic sea-level changes.     

Platform configuration, microfacies and cyclicities of the upper Albian to Turonian of west-central Jordan

We present a comprehensive facies scheme for west-central Jordan platform deposits of upper Albian to Turonian age, discuss Cenomanian and Turonian carbonate cycles, and reconstruct the paleogeographic evolution of the platform. Comparisons with adjacent shelf areas (Israel, Sinai) emphasize local characteristics as well as the regional platform development. Platform deposits are subdivided into fifteen microfacies types that define eight environments of deposition of three facies belts. Main facies differences between Cenomanian and Turonian platforms are: rudist-bearing packstones that characterise the higher-energy shallow subtidal (transition zone) during the Cenomanian, and fossiliferous (commonly with diverse foraminifer assemblages) wackestones and packstones of an open shallow subtidal environment. On Turonian platforms high-energy environments are predominantly characterised by oolithic or bioclastic grainstones and packstones, whereas peritidal facies are indicated by dolomitic wackestones with thin, wavy (cryptmicrobial) lamination. Rhythmic facies changes define peritidal or subtidal shallowing-up carbonate cycles in several Cenomanian and Turonian platform intervals. Cyclicities are also analysed on the base of accommodation plots (Fischer Plots). High-frequency accommodation changes within lower Cenomanian cyclic bedded limestones of the central and southern area exhibit two major cyclic sets (set I and II) each containing regionally comparable peaks. Accommodation patterns within cyclic set II coincide with the sequence boundary zone of CeJo1. The lateral and vertical facies distributions on the inner shelf allow the reconstruction of paleogeographic conditions during five time intervals (Interval A to E). An increased subsidence is assumed for the central study area, locally (area of Wadi Al Karak) persisting from middle Cenomanian to middle Turonian times. In contrast, inversion and the development of a paleo-high have been postulated for an adjacent area (Wadi Mujib) during late Cenomanian to early Turonian times, while small-scale sub-basins with an occasionally dysoxic facies developed northwards and further south during this time interval. A connection between these structural elements in Jordan with basins and uplift areas in Egypt and Israel during equivalent time intervals is assumed. This emphasises the mostly concordant development of that Levant Platform segment.     

Les kystes de dinoflagellés du Crétacé moyen de la marge atlantique brésilienne, le bassin de Santos

Organic dinoflagellate cysts are studied from the sedimentary sequence of hole 1-SPS-14A, drilled during oil exploration in the Santos Basin, Brazilian continental margin. The Ariri and Florianópolis Formations (Transitional sequence) do not contain any dinocysts. The oldest found dinocysts occur at the base of the Drift sequence in sediments, within platform carbonates of the Guarujá Formation. Continuous sea-level rise throughout the late Albian and Cenomanian submerged the carbonate platform with the terrigenous input of the Itanhaém Formation. The transgressive phase reached its peak during the Cenomanian/Turonian transition. Pelites were deposited during oceanic anoxic event (OAE-2), consisting the lower part of the Itajaí-Açu Formation. Normal oceanic conditions re-established in the late Turonian. The Brazilian dinocyst assemblage has tethyan affinities. Some species (i.e., Dinopterygium cladoides, Litosphaeridium arundum, Odontochitina rhakodes and Systematophora cretacea) suggest a middle Albian age for the carbonate platform of the Guarujá Formation. The lower part of the Guarujá Formation was not dated by other microfossils. An uppermost Albian or lower Cenomanian age is suggested for the base of the Itanhaém Formation on the basis of species Palaeohystrichophora infusorioides and Ovoidinium verrucosum. The Cenomanian-Turonian boundary cannot be characterized by dinocysts. Species Atopodinium iuvene, which is known from Turonian sediments in Europe, was found at the top of the Itajaí-Açu Formation. The observed dinocyst bioevents (i.e., last occurrence) are correlated with known foraminiferal, nannofossil and other palynological bioevents. The diversity of the assemblages remains constant throughout the various palaeoenvironments as these are reflected by the Guarujá and Itajaí-Açu Formations, but relative abundances of taxa are variable. Genera Coronifera, Florentinia, Ovoidinium, Spiniferites and Trichodinium are abundant in the carbonate platform assemblages (Guarujá Formation). Genera Cribroperidinium and Cyclonephelium are abundant in detrital sediments (Itajaí-Açu Formation). Only one species (Subtilisphaera guarujaensis n. sp.) is restricted to the carbonate platform environment.     

Late Cretaceous (Cenomanian–Maastrichtian) calcareous nannofossils from Goban Spur (DSDP Sites 549, 551): Implications for the palaeoceanography of the proto North Atlantic

The early late Cretaceous (Cenomanian–early Turonian) is thought to have been one of the warmest periods of the Phanerozoic. This period was characterised by tropical sea surface temperatures of up to 36 °C and a pole-to-equator-gradient of less than 10 °C. The subsequent Turonian–Maastrichtian was characterised by a continuous climatic cooling, peaking in the Maastrichtian. This climatic cooling and the resulting palaeoceanographic changes had an impact on planktic primary producer communities including calcareous nannofossils. In order to gain a better understanding of these Cenomanian–Maastrichtian palaeoceanographic changes, calcareous nannofossils have been studied from the proto North Atlantic (Goban Spur, DSDP Sites 549, 551). In order to see potential differences between open oceanic and shelf dwelling nannofossils, the data from Goban Spur have been compared to findings from the European shelf (northern Germany).A total of 77 samples from Goban Spur were studied for calcareous nannofossils revealing abundant (mean 6.2 billion specimens/g sediment) and highly diverse (mean 63 species/sample) nannofossil assemblages. The dominant taxa are Watznaueria spp. (mean 30.7%), Prediscosphaera spp. (mean 18.3%), Zeugrhabdotus spp. (mean 8.3%), Retecapsa spp. (mean 7.2%) and Biscutum spp. (mean 6.6%). The Cenomanian assemblages of both Goban Spur (open ocean) and Wunstorf (shelf) are characterised by elevated abundances of high fertility taxa like Biscutum spp., Zeugrhabdotus spp. and Tranolithus orionatus. Early Turonian to Maastrichtian calcareous nannofossil assemblages of Goban Spur are, however, quite different to those described from European sections. Oceanic taxa like Watznaueria spp., Retecapsa spp. and Cribrosphearella ehrenbergii dominate in Goban Spur whereas the fertility indicators Biscutum spp. and T. orionatus are more abundant in the European shelf assemblages. This shift from a homogeneous distribution of calcareous nannofossils in the Cenomanian towards a heterogeneous one in the Turonian–Maastrichtian implies a change of the ocean circulation. The “eddy ocean” system of the Cenomanian was replaced by an oceanic circulation similar to the modern one in the Turonian–Maastrichtian, caused by the cooling. The increased pole-to-equator-gradients resulted in an oceanic circulation similar to the modern one.     

The demise of the rudist-bearing carbonate platforms at the Cenomanian/Turonian boundary: a global control

The demise of the rudist-bearing carbonate blatforms at the Cenomanian/Turonian boundary is tudied in different ways through examples from the Vestern Mediterranean Province. During the Late Cenonanian, North and South Tethyan carbonate platforms xtened widely and were subjected to different climatic and oceanographic conditions. The onset of the demise of the carbonate platforms occurred during Upper Arphaeocretacea and Helvetica biozone times and was boeval with the Global Oceanic Anoxic Event (OAE₂). A major biologic turnover affected the benthic organisms i.e. rudists and large foraminifera. The rudists underwent a severe extinction event, leading to the disappearance of the dominantly aragonite secreting rudists, while the dominantly calcitic forms were less affected. The major development of the carbonate platforms occurred during the Latest Cenomanian — Earliest Turonian, involving a transgressive highstand system tract and a keep-up carbonate organization. During the Early Turonian the carbonate sedimentation was disturbed; hard-grounds, condensed beds, terrigenous inputs developed and a gap in the carbonate platform deposition occurred. A combination of several sequentially linked factors, could explain the demise of the carbonate platform and the major change on the benthic ecosystem at the Cenomanian-Turonian boundary.     

The Cenomanian–Turonian boundary in Jordan: Ammonite biostratigraphy and faunal turnover

Well-exposed fossiliferous Upper Cenomanian–Lower Turonian marine sedimentary rocks are present in west-central Jordan. Ammonites serve as an important faunal marker for this interval and can be used to subdivide the Cenomanian–Turonian transition into two upper Cenomanian biozones (Neolobites vibrayeanus and Vascoceras cauvini) and two lower Turonian biozones (Vascoceras proprium and Choffaticeras segne). A revised stratigraphic range of the Vascoceras cauvini Zone in the study area is proposed, consisting of the Metoicoceras geslinianum and Neocardioceras juddii zones of the standard zonation. Based on intercontinental biostratigraphic correlation, a minor unconformity appears to be present around the Cenomanian–Turonian boundary, and a part of the lower Turonian is probably missing. In addition, a faunal turnover is recorded in the uppermost Cenomanian, marked by the disappearance of most of the Cenomanian taxa, including Costagyra olisiponensis (Sharpe), Ceratostreon flabellatum (Goldfuss), Ilymatogyra africana (Lamarck), Rhynchostreon suborbiculatum (Lamarck), Harpagodes nodosus (Sowerby), and Heterodiadema libycum (Desor). This bioevent is thought to be an effect of the Oceanic Anoxic Event OAE 2; the dramatic shifts in species richness and diversity spanning the Cenomanian–Turonian boundary in the study area occurred in response to the major paleoclimatic and paleoenvironmental perturbations prevailing at that time. The stratigraphic and paleontological patterns studied in Jordan are very similar to those recorded in Egypt in terms of litho- and biostratigraphy, event stratigraphy, and macroinvertebrate content, suggesting the presence of uniform triggering mechanisms and bio-sedimentary responses in the Upper Cretaceous basins of the Middle East and providing clues for a high-resolution correlation between the two areas.     

Facies pattern and sea-level dynamics of the early Late Cretaceous transgression: a case study from the lower Danubian Cretaceous Group (Bavaria,southern Germany)

The facies development and onlap pattern of the lower Danubian Cretaceous Group (Bavaria, southern Germany) have been evaluated based on detailed logging, subdivision, and correlation of four key sections using an integrated stratigraphic approach as well as litho-, bio-, and microfacies analyses. Contrary to statements in the literature, the transgressive onlap of the Regensburg Formation started in the Regensburg–Kelheim area already in the early Early Cenomanian Mantelliceras mantelli ammonite Zone and not in the Late Cenomanian. In the Early Cenomanian, nearshore glauconitic-bioclastic sandstones prevailed (Saal Member), followed by Middle to lower Upper Cenomanian mid-shelf siliceous carbonates intercalated with fine-sandy to silty marls (Bad Abbach Member). Starting in the mid-Late Cenomanian (Metoicoceras geslinianum ammonite Zone), a considerable deepening pulse during the Cenomanian–Turonian Boundary Event (CTBE) initiated the deposition of the deeper shelf silty marls of the Eibrunn Formation, which range into the early Early Turonian. During the CTBE transgression, also the proximal Bodenwöhrer Senke (ca. 40 km NE of Regensburg) was flooded, indicated by the onlap of the Regensburg Formation onto Variscan granites of the Bohemian Massif, overlain by a thin tongue of lowermost Turonian Eibrunn Formation. A detailed record of the positive δ¹³C excursion of the global Oceanic Anoxic Event (OAE) 2 has been retrieved from this shallow-water setting. An integrated approach of bio-, event-, carbon stable isotope and sequence stratigraphy was applied to correlate the sections and to decipher the dynamics of this overall transgressive depositional system. The Cenomanian successions show five prominent unconformities, which correlate with those being known from basins in Europe and elsewhere, indicating their eustatic origin. The rate of sea-level rise during the CTBE suggests glacio-eustasy as a driving mechanism for Late Cenomanian sea-level changes. The Regensburg and Eibrunn formations of the lower Danubian Cretaceous Group are highly diachronous lithostratigraphic units. Their regional distribution and northeast-directed onlap pattern onto the southwestern margin of the Bohemian Massif can readily be explained by the lateral movements of roughly coast-parallel (i.e., NW/SE-trending) facies belts of a graded shelf system transgressing on a northeastward-rising substrate. It took the Cenomanian coastline ca. 6 Ma to transgress from southwest of Regensburg to the topographically elevated granite cliffs southeast of Roding in the Bodenwöhrer Senke (=60 km distance).     

Some rudists from Khalsi limestone of Indus Formation,Ladakh Himalaya

The paper describes three taxa of rudists, namely Eoradiolites gilgitensis Douvillé? Horiopleura sp. and cf. Toucasia sp., from the Khalsi limestone of Indus Formation, Ladakh Himalaya exposed 2.5 kms East of Khalsi. The age and affinity of the rudist fauna have also been discussed.     

Biometry of Cenomanian–Turonian placoliths: a proxy for changes of fertility and surface‐water temperature?

Most publications discussing Cenomanian–Turonian calcareous nannofossils focus on abundance fluctuations across the boundary interval. So far, there have been no studies that deal with the influence of palaeoenvironmental changes on the size of common Cenomanian–Turonian nannofossil taxa. The genera Biscutum, Broinsonia, Prediscosphaera, Retecapsa and Watznaueria have therefore been analysed from 19 samples of Cenomanian–Turonian age from the Goban Spur, northeast Atlantic. The genus Biscutum shows a slight decrease of mean length from 4.14 μm in the Cenomanian to 3.94 μm in the Turonian. Broinsonia is marked by a decrease from 6.07 μm in the Cenomanian to 5.64 μm in the Turonian. On the other hand, Prediscospheara increases in size from 4.98 μm in the Cenomanian to 5.61 μm in the Turonian. Two genera (Retecapsa, Watznaueria) show no significant changes in their mean length. The mean size of Biscutum is perhaps controlled by nutrients, where larger specimens may have preferred the more fertile palaeoenvironment of the Late Cenomanian. The size decrease of Biscutum in the Turonian is probably related to reduced nutrient availability. The genus Prediscosphaera spp., may have favoured low‐fertility conditions, as its mean size increases in the Turonian. A worldwide decline of the frequency of Broinsonia spp. during the Cenomanian–Turonian transition implies that this genus is not solely controlled by the nutrient content. The size of Broinsonia spp. may have been therefore influenced by the latest Cenomanian warming event. The increase in sea‐surface temperature may have been unfavourable for Broinsonia spp. as reflected by decreasing mean size and frequency. □Calcareous nannofossils, biometry, morphometry, Oceanic Anoxic Event 2.     

Mammalian Faunal Succession in the Cretaceous of the Kyzylkum Desert

Both metatherians and eutherians are known from the Early Cretaceous (Barremian, 125 mya; million years ago) of China, while eutherian-dominated mammalian faunas appeared in Asia at least by the earliest Late Cretaceous (Cenomanian, 95 mya). The approximately 99–93 my old (Cenomanian) Sheikhdzheili l.f. from western Uzbekistan is a small sample of only eutherians, including three zhelestids and a possible zalambdalestoid. The much better-known 90 my old (Turonian) Bissekty l.f. at Dzharakuduk in the central Uzbekistan includes 15 named and unnamed species, based on ongoing analyses. Of these, 12 are eutherians represented by at least the three groups—asioryctitheres, zalambdalestids, and zhelestids—plus an eutherian of uncertain position—Paranyctoides. Zalambdalestids and zhelestids have been argued to be related to the origin of the placental gliriforms (Euarchontoglires) and ferungulates (Laurasiatheria), respectively. Although there are four previously recognized metatherians, we believe three are referable to the deltatheroid Sulestes karakshi and the fourth, Sailestes quadrans, may belong to Paranyctoides. There is one multituberculate and one symmetrodont in the Bissekty l.f. While comparably aged (Turonian) localities in North America have somewhat similar non-therians, they have more metatherians and no eutherians. The next younger localities (early Campanian, ∼80 mya) in North America have both a zhelestid and Paranyctoides, suggesting dispersal of eutherians from Asia. At Dzharakuduk, the approximately 85 my old (late Turonian/Coniacian) Aitym l.f. is much less well known than the Bissekty l.f., but yields nearly identical taxa, with two non-therians, one metatherian, and six eutherians.     

Cretaceous (Albian to Turonian) radiolarians from chert blocks of the Moni Mélange (Southern Cyprus)

Well-preserved Cretaceous (Albian–Turonian) radiolarians were extracted from radiolarian-bearing chert olistoliths of the Monagroulli Member within the Moni Mélange (Campanian-Maastrichtian, Southern Cyprus). Four assemblages were distinguished: Middle Albian–Lower Cenomanian (Thanarla spoletoensis Zone), Upper Albian–Lower Cenomanian (Thanarla spoletoensis Zone, Dorypyle? anisa Subzone), lowermost Turonian (base of Alievium superbum Zone) and Lower Turonian (Alievium superbum Zone). The radiolarian assemblages are diverse and have taxonomic composition similar to coeval assemblages of Italy and Spain. The sediments of the Monagroulli Member differ from coeval rocks of the Mamonia Complex (western Cyprus) by the more common presence of radiolarian cherts and may have been formed in the distal part of a continental margin with less input of clastic material. A new spicular radiolarian genus Cyprothamnus with 2 new species (C. multifurcatus and C. moniensis) is described from the Lower Turonian strata.     

Benthic foraminiferal assemblages of the Cretaceous platform carbonate succession in the Yavca area (Bolkar Mountains, S Turkey): biostratigraphy and paleoenvironments

The microbiostratigraphic analysis of the three outcrop sections from the Cretaceous inner platform carbonate succession in the Yavca area (Bolkar Mountains) allows to recognize the four local benthic foraminiferal zones. These are: (1) Voloshinoides murgensis and Praechrysalidina infracretacea Cenozone in the Lower Aptian; (2) Pseudorhapydionina dubia and Biconcava bentori Cenozone in the Middle-Upper Cenomanian; (3) Ostracoda and Miliolidae Interval Zone in the probable Turonian, represented by dolomitized limestones without any significant markers; (4) Moncharmontia compressa and Dicyclina schlumbergeri Cenozone in the Coniacian-Santonian. The benthic foraminiferal assemblages correspond to those in other areas of the Mediterranean realm, with the exception of a lack of alveolinids and orbitolinids due to unfavorable environmental conditions (inner platform, restricted shelf). After the regionally well-known emergence during the late Aptian, Albian and early Cenomanian, very shallow subtidal to intertidal conditions were re-established during the middle-late Cenomanian time. The Coniacian-Santonian benthic foraminiferal assemblage shows an increase in diversity and abundance as a result of open marine influence, confirmed by the presence of larger foraminifera (Dicyclina), Rotaliidae and radiolitid fragments. Thaumatoporella and Aeolisaccus-bearing wackestone intercalations still indicate the existence of sporadic restricted environment conditions. The Cretaceous shallow-water platform carbonate succession of the Yavca area is conformably overlain by gray pelagic limestones with calcispheres and planktonic foraminifera. The Campanian flooding of the Bolkar Da? carbonate platform resulted in drowning of the pre-existing biota and facies.     

A crinoid concentration Lagerstätte in the Turonian (Late Cretaceous) Conulus Bed (Miechów-Wolbrom area, Poland)

More than one hundred centrodorsals of the comatulid crinoid Glenotremites paradoxus have been found in Turonian deposits (Upper Cretaceous) in the Miechów-Wolbrom area (southern Poland). This is the first dense occurrence of the genus Glenotremites in the Upper Cretaceous of Poland. Furthermore, so many individuals of this species in one level (the so-called Conulus Bed) forming a crinoid Konzentrat-Lagerstätte are very surprising because only disarticulated remains (cirrals and brachials) are encountered in the older (Cenomanian and earliest Turonian) and younger (late Turonian) deposits. The Glenotremites individuals are accompanied by isocrinids, which prove that stalked forms remained in shallow-water settings for some time after the initiation of the Mesozoic marine revolution.     

Actinocamax primus arkhangelsky (belemnitellidae; upper cretaceous) biometry,comparison and biostratigraphy

A sample ofActinocamax primus Arkhangelsky, 1912 from the Lower Middle Cenomanian limestones of the Wunstorf quarry west of Hannover (NW Germany) is studied by univariate and bivariate biometric methods in order to analyse the variation of critical characters.A. primus is closely related toA. plenus (Blainville, 1825) but differs from that species by being smaller and more slender.A. primus appears in the Lower Cenomanian and continues into the Lower Middle Cenomanian. It is mainly distributed in the northern part of the North European Palaeobiogeographic Province.A. plenus is recorded from the Middle Cenomanian-lower Lower Turonian of the Russian Platform, but only from the Middle Upper Cenomanian in NW Europe. It is widespread in the North European Province.The primus event in the Lower Middle Cenomanian and theplenus event in the Middle Upper Cenomanian are briefly discussed.