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The present work focuses on the upper Cretaceous (Cenomanian-early Campanian) carbonate successions in selected wells from northwestern Iraq. These successions are represented by Gir Bir (Cenomanian-early Turonian), Wajna (late Santonian) and Mushorah (early Campanian) Formations. The succession has affected by early burial near-surface, unconformity-related and deep burial diagenesis represented by cementation, neomorphism, dolomitization, dedolomitization, silicification, authigenesis of glauconite and pyrite, compaction, micritization, solution and porosity formation. The common porosity types are intergranular, fenestral, intercrystalline, moldic, vuggy, channel and fracture. Three porosity zones (I, II, and III) are identified depending on variation in gamma ray which reflects their shale content. The upper part of zone (II) is highly porous and regarded on the main reservoir unit in the middle and upper parts of the Gir Bir Formation. Fracture and moldic and vuggy dissolution features in addition to karstic and fissure features are responsible for the porosity increase in the fractured reservoir unit.

The Cerro Overo-La Invernada area in north Patagonia has provided a rich record of Cretaceous continental tetrapods in the last two decades, mainly from the Bajo de la Carpa Formation (Upper Cretaceous, Santonian). The dinosaur fauna from this area is diverse, including several new taxa, with abelisaurid theropods particularly abundant. Recently, a new isolated caudal vertebra (MAU-Pv-CO-598) was here recovered. Although fragmentary, it shows features that differentiate it from other abelisaurid remains previously found in this area. It is considered a mid-caudal vertebra and is mainly characterized by a longitudinal groove on the ventral surface of the centrum; a scarcely elevated transverse process with an anteroposteriorly expanded and laterally concave distal end; a longitudinal dorsal crest anteriorly extended from the anterior border of the neural spine; and small tubercles extended from the ends of the zygapophyses, which are considered as accessory interlocking structures between vertebrae. Some characters, such as the dorsal longitudinal crest and the accessory tubercles of the zygapophyses, are present also in the non-brachyrostran abelisaurid Majungasaurus. However, the transverse process is similar to that of caudal vertebrae of non-furileusaur brachyrostrans, such as Ilokelesia, Ekrixinatosaurus, and Skorpiovenator. A phylogenetic analysis here conducted clusters MAU-Pv-Co-598 with the latter three taxa. MAU-Pv-CO-598 comes from lower levels of the Bajo de la Carpa Formation than the furileusaurs Viavenator and Llukalkan. The presence of a specimen with non-furileusaurian affinities in this formation indicates that a possible replacement from non-furileusaur to furileusaur brachyrostrans occurred during the Santonian, after the proposed Turonian faunal turnover.

The Cenomanian/Turonian strata of the Kasserine area: Tunisia exhibit a unique sedimentological and palaeontological pattern. Five lithological units have been identified: 1) lower unfossilferous black shale; 2) well-bedded marly unit with thin limestone interbeds; 3) marl unit, 4) same as 2, and 5) unfossilferous dolomitic thick-bedded limestone. The middle three units contain low diversity macrofaunal communities dominated mainly by oyster bivalves with few gastropods and echinoids. Fortunately, three marker ammonite species were identified and are used to subdivide the studied interval into three biozones, including 1) Calycoceras cenomanense, 2) Pseudaspidoceras pseudonodosoides and 3) Neoptychites Cephalotus. Based on constrained clustering and ordination techniques, three distinct macrofaunal associations were identified: 1) Ceratostreon flabellatum, 2) Ilymatogyra africana and 3) Tylostoma (Tylostoma) globosum. In general, the macrofaunal diversity decreases at the Cenomanian-Turonian boundary, which is interpreted to be a consequence of a global sea-level rise and the destruction of shallower habitats. Based on the life habits of the macrofaunal communities, a change from a high-energy (Ceratostreon and Ilymatogyra) to a low-energy (Tylostoma) shallow marine environment was indicated. The dominance of oysters in these nutrient-rich sediments was attributed to their ability to tolerate high turbidity water and to colonise soft-substrate sea bottoms. [ABSTRACT FROM AUTHOR]

Here we determine the individual age of a basal mosasaur (subfamily Halisaurinae) using zygapophyseal skeletochronology. This study is based on the cervical vertebra from the Late Cretaceous Beloe Ozero locality (Saratov Region). By of counting the zygapophyseal growth rings on the right prezygapophysis, it has been revealed that the age of the animal to which this vertebra belonged was at least 11 years. The absence of drastic reduction in the distance between the zygapophyseal growth rings is indicative of the fact that in the first 11 years of life, until the moment of death, the animal grew rapidly and evenly and reached a length of about 6 meters. [ABSTRACT FROM AUTHOR]

Here we describe the first occurrence of the stem turtle Naomichelys from the Late Cretaceous of eastern North America. The specimen (MSC 41038) was collected as float from locality AMg-1 in Montgomery County, Alabama, USA. Although this locality consists of exposures of both the upper Santonian Tombigbee Sand Member of the Eutaw Formation and Mooreville Chalk, it is likely that the specimen was derived from the latter unit, which is known to possess both nearshore and terrestrial components. The specimen consists of a single incomplete peripheral and is referred to Naomichelys based on its Santonian age and the presence of numerous cylindrical tubercles covering the surface of the element that never coalesce and are easily dislodged. The presence of Naomichelys in the Gulf Coastal Plain greatly expands the geographical range of helochelydrids in North America. This occurrence indicates that helochelydrid turtles were likely a well-established component of the Appalachian terrestrial fauna and reinforces the emerging pattern of faunal similarities between Laramidia and Appalachia seen in Late Cretaceous non-avian dinosaurs. The recovery of helochelydrid remains from the Santonian of Alabama therefore represents an important contribution to our understanding of the terrestrial palaeoecology of Appalachia. [ABSTRACT FROM AUTHOR]

Provenance study of the Upper Cretaceous – Paleocene turbiditic deposits of the Pupov Formation with uncertain tectonic affiliation exposed in the Varín sector of the Pieniny Klippen Belt is presented. Petrographic and heavy mineral analyses including geochemistry of detrital Cr-spinels, tourmalines and garnets were carried out. The studied deposits include litho-quartzose to feldspatho-litho-quartzose sandstones, fine-grained conglomerates and pebbly mudstones. They contain mostly lithoclasts of low- to medium-grade metamorphic rocks, basic volcanites and carbonates. Impoverished heavy mineral assemblage includes ultrastable tourmaline, zircon, rutile accompanied by Cr-spinel and apatite. Garnets, exclusively of almandinic composition, are rare, except of one locality from pebbly mudstone where they dominate. Cr-spinels of harzburgitic peridotite composition derived from supra-subduction zones dominate over Cr-spinels of volcanic origin. Detrital tourmalines include besides schorlitic-dravitic tourmalines also subhedral to angular distinctly zoned tourmalines of schorlitic-dravitic and magnesiofoititic to foititic compositions with fine intergrowth with quartz and tourmalines possessing magnesiofoititic-foititic cores and schorlitic-dravitic rims. The primary source for the Cr-spinels and complexly zoned tourmalines appears to be in Meliata ophiolite-bearing complexes feeding flysch deposits in the original Fatric Zliechov Basin. After the Turonian emplacement of the Fatric nappe system beyond the Tatric edge, the exotics-bearing formations of the Klape Unit formed the source of ophiolitic detritus in foreland basins of the developing accretionary wedge. Based on the specific structural position, age, lithological composition and impoverished heavy mineral assemblage, the Pupov Formation could represent a part of the wedge-top Gosau-type basin system developed during the meso-Alpidic (Coniacian–Eocene) tectonic epoch. [ABSTRACT FROM AUTHOR]

Over 3,000 m of Upper Cretaceous‐Lower Palaeocene sediments belonging to the Tarbur Formation were studied in seven stratigraphic sections around Shiraz city (south Zagros Basin, SW of Iran). The Tarbur Formation is divided into two informal lithostratigraphic units: a lower well‐bedded rudist limestone and an upper massive rudist limestone. Both units comprise rudist particles as a major organo‐detrital component. Microscopic studies have identified the presence of the following carbonate microfacies types in the Tarbur Formation: rudist orbitoid wackestone, miliolid algal‐bioclast wackestone, rudist packstone, rudist orbitoid packstone, rudist intraclast miliolid packstone, rudist‐agglutinated foraminifer grainstone, orbitoid rudist grainstone, rudist‐hyaline foraminifer‐intraclast grainstone, rudist boundstone and coral boundstone, which are attributed to shallow water lagoon, bar and fore‐reef palaeoenvironments. The rudist fragments co‐existed with a Campanian/Maastrichtian foraminiferal assemblage. The stratigraphic distribution of the investigated microfacies was affected by vertical displacement of studied area basement faults. [ABSTRACT FROM AUTHOR]

Visits to paleontological sites are one of the most popular geotourism activities, but their appeal may have drawbacks. Deciding which sites are suitable for dissemination and appropriate measures for their optimal conservation can be complex. Here, we present a geoconservation inventory of 15 Upper Cretaceous paleontological sites with dinosaur and other vertebrate remains from the Origens UNESCO Global Geopark. We provide a summary of the inventory and methodology used to characterize the geosites. We used a modified version of a geoconservation questionnaire developed by the Spanish Geological Survey that allows systematic characterization of the sites and diagnosis of their geo-touristic and educational potential, as well as their susceptibility to degradation through exposure to local environmental conditions, vandalism, and spoliation. Based on these criteria, protection and conservation measures tailored to the needs of each site are recommended. Our aim is to address questions on previously published geoconservation measures and to establish a preliminary systematic approach in the characterization, diagnosis, and protection of vertebrate paleontological sites in the Spanish Pyrenees.

Upper Cretaceous vertebrate records from Chile are mostly known by historical mentions with unknown repositories and uncertain stratigraphic provenance. This contribution reviews and complements two marine vertebrate assemblages from the Upper Cretaceous of central Chile, which were part of the ancient Arauco Basin. The oldest assemblage (lower Maastrichtian) comprises abundant condrichthyans referred to Carcharias gracilis , Odontaspis cf. winkleri , Scapanorhynchus sp., Centrophoroides appendiculatus , Squatina sp., Cretorectolobus sp., Orectolobidae indet., Paraorthacodus sp., Ischyrhiza chilensis and Biropristis landbecki , which adds to the previously reported occurrences of Echinorhinus sp. and Myledaphus araucanus. In addition, chimeroids referred to as Edaphodon kawai and remains of a leatherback turtle referable to Mesodermochelys sp. are here described, the latter being its first occurrence outside Japan. The younger assemblage (upper Maastrichtian) includes similar chondrichthyans and a higher diversity of marine reptiles, including plesiosaurians (Aristonectes sp., Aristonectinae indet., and Elasmosauridae indet.), sea turtles (Pancheloniidae indet.) and diverse mosasaurs (Halisaurus sp., Tylosaurinae indet., and the first local occurrence of Plioplatecarpinae indet.). Throughout the Maastrichtian, the local marine vertebrates likely suffered a declination in abundance but a rise in diversity, with evidence of a marked alteration in middle levels of the trophic web during the upper Maastrichtian. This fauna shows a main influence from the northern hemisphere (especially from the Western Interior Sea), acquiring a more marked Weddellian influence during the end of the Maastrichtian. The studied material allows a better understanding of the Upper Cretaceous vertebrate marine fauna in lower latitudes of the southeastern Pacific. [ABSTRACT FROM AUTHOR]

The late Campanian-Maastrichtian in the Ibero-Armorican domain is rich in titanosaurian fossils. The sauropod remains exhibit a high degree of morphological variability, especially in the commonly-found appendicular elements. The phylogenetic relationships of the Ibero-Armorican titanosaurs are still uncertain but we do know that they experienced a Campanian-Maastrichtian herbivorous faunal turnover. It is probable that the small-to-medium-sized Lirainosaurinae-dominated faunas of the Campanian were replaced by late–early Maastrichtian large-bodied lithostrotian dominated faunas. In this context, the Villalba de La Sierra Formation has yielded an abundant sample of medium-to-large sized titanosaurs. In this study we analyze the morphological variability in the appendicular skeleton of the titanosaurs from the Campanian-Maastrichtian Ibero-Armorican domain. We follow previous attempts to classify the commonly-found isolated titanosaurian femora and expand the proposed methodology. The use of combined phenotypic characters and linear morphometrics can be helpful to analyze the morphological variability and diversity of the Ibero-Armorican titanosaurs. Our findings corroborate the presence of at least two exclusive morphotypes in the Lo Hueco fossil site and one exclusive morphotype in the Poyos site, as well as the presence of previously defined Lirainosaurinae across the Pyrenees during the Campanian-Maastrichtian. The Villalba de La Sierra Formation titanosaurs are also clustered with large-bodied late Maastrichtian titanosaurs. It is possible that either the large-bodied late–early Maastrichtian immigrants, with possible Gondwanan affinities, entered the Iberian Peninsula much earlier or that this group was already present at least during the Campanian-Maastrichtian transition, as the small-sized Lirainosaurinae declined. [ABSTRACT FROM AUTHOR]

The article presents the results of cytoembryological research of the structure of fossil seeds in coniferous plants Alapaja cf. uralensis (Cupressaceae) from the Cenomanian–Turonian deposits of Western Siberia (age about 91.5 ± 8.5 Mya), and the results of the Feulgen test for the preservation of their structures' paleo-DNA in the nuclei. The study revealed the presence of fragments of embryo, megagametophyte and nucellus in the seed. The presence of megaspore membrane was also identified in the seed. The seed coat is 2–3-layered, the upper layer is very thin and presents just partially, and the middle layer of testa is represented by sclerotesta, the lower layer cells are fused into a single mass. It was established that nuclei are present in the cells of the embryo, megagametophyte and nucellus, however, in most cases, the DNA-deoxyribose skeleton, serving as a target for the Schiff reagent during the Feulgen reaction, is not cytologically detected in the nuclear chromatin. Only in two cases: in fragments of presumably embryonic tissue and megagametophyte, nuclei with a positive reaction according to Felgen were found, which indicates the preservation of aldehyde groups of deoxyribose in the nuclei of its individual parts. • The structure of fossil seeds of Alapaja cf. uralensis (Cupressaceae) from the Cenomanian–Turonian deposits. • The presence of fragments of embryo, megagametophyte and nucellus in the seed. • In the nuclear chromatin in the cells the DNA-deoxyribose skeleton is not cytologically detected. • In two fragments of embryo and megagametophyte tissues, nuclei with a Felgen-positive reaction were detected [ABSTRACT FROM AUTHOR]

The lake transgression event (LTE) associated with a lake anoxic event (LAE) has been reported previously from the Cretaceous Nenjiang Formation in the Songliao Basin, NE China. Detailed studies based on sedimentology, dinoflagellates, ostracods, and biomarkers have provided important evidence for this LTE in Member 1 of the Nenjiang Formation (K 2 n1). However, the related floristic record has not received enough attention. In this paper, palynological data of borehole Ji Tao Di-1 (JTD-1) from the western slope of the Songliao Basin were analyzed to investigate vegetation and climate changes associated with this Cretaceous LTE. Three palynological sub-assemblages reflect significant paleovegetation and paleoclimate changes through this LTE and reveal ecosystem fluctuations related to the global Cretaceous oceanic anoxic event (OAE3). A significant increase in the relative abundance of Schizaeoisporites and Cyathidites spores may represent the LTE in the Nenjiang Formation. Principal Components Analysis (PCA) and Sporomorph EcoGroup (SEG) model indicate that climate changed from cool and humid subtropical before the LTE, to relatively warm temperate during the LTE and temperate after the LTE in this area. The relatively warmer and drier climate during the later period of the LTE may be influenced by the contemporaneous OAE3. After the LTE, the highland mixed forests were dominant, and a large number of angiosperms (i.e., members of the Proteaceae) occupied the ecological niches of the middle canopy, indicating that the flourishing of angiosperms in the late Santonian may be closely related to environmental disturbances resulted from the LTE and OAE. • The palynological turnover revealing significant ecosystem fluctuations across LTE. • According to PCA and SEG model, the climate changes across LTE could be influenced by the contemporaneous OAE3. • The flourishing of angiosperms in late Santonian may be closely related to the LTE and OAE. [ABSTRACT FROM AUTHOR]

The first findings of frogs (Anura) from the Upper Cretaceous of Russia—the distal part of the humerus and a tibiofibula fragment—were described. They come from the Maastrichtian dinosaur locality in the city of Blagoveshchensk (Amur oblast). The described remains are characterized by the outer and inner structure typical of Anura, and their exact taxonomic affiliation is not defined. These are the easternmost and the youngest frog remains from the Upper Cretaceous of Asia. [ABSTRACT FROM AUTHOR]

The Gobi Desert of southern Mongolia is home to an incredibly rich record of dinosaurs and other vertebrate fossils from the latest Cretaceous Period. Together, more than a dozen sites in several basins have produced one of the richest palaeofaunas known from this interval anywhere in the world. Most of this diversity has been recovered from the fluvial deposits of the Nemegt Formation. Despite historic and ongoing research in southern Mongolia, accurate maps and geological data for the main fossil sites are still lacking, limiting our ability to investigate how local palaeoecological dynamics influenced Nemegt taxa, their geographic distribution, and their evolutionary patterns. One of these sites, Guriliin Tsav, has produced more than a hundred significant fossil specimens to date, but still remains one of the lesser known Nemegt localities. In part this is because many expeditions have instead focused on the nearby Bügiin Tsav, one of the largest and richest localities for the Nemegt Formation. To address this gap, a project was initiated in 2018 to produce a high-resolution topographic map of Guriliin Tsav using Unmanned Aerial Vehicles (UAV), and consequently, to plot the geographic and stratigraphic distributions of palaeontological resources on this map. In so doing, we also collected stratigraphic and taphonomic data from the area, allowing for the first detailed palaeoecological interpretation of Guriliin Tsav and a comparison with other localities of southern Mongolia. Here we present the results of this project, and also discuss new topographic and stratigraphic data from Bügiin Tsav. This sheds new light into the temporal and geographic distribution of vertebrate taxa in the latest Cretaceous of Mongolia. • We provide the first high-resolution maps of Guriliin Tsav, a rich Gobi Desert fossil locality. • We comprehensively describe the stratigraphy and taphonomy of the site and its impact on fossil resources. • We tabulate more than 100 fossil occurrences into the first detailed documentation of the fauna at Guriliin Tsav, showing distinct differences from sites further southeast. • We document Baruungoyot-like aeolian beds within the middle Nemegt Formation, challenging assertions that these represent sequential time intervals. • We demonstrate how channel architecture at Bugiin Tsav and Guriliin Tsav corresponds to spatial distribution of fossils. [ABSTRACT FROM AUTHOR]

The aim of the present contribution is to describe the first ornithischian species from the Huincul Formation (Cenomanian-Turonian, Upper Cretaceous) at the Pueblo Blanco Natural Reserve, Río Negro province, Argentina. The new species, named Chakisaurus nekul gen. et sp. nov., can be comfortably included among elasmarian ornithopods. The new species shows humeral anatomy that is congruent with smaller members of the clade (e.g. Anabisetia, Notohypsilophodon), and differs from larger taxa (e.g. Talenkauen, Mahuidacursor) which show humeral features probably related with graviportal habits, such as lack of shaft torsion and a distally located deltopectoral crest. This indicates that graviportal habits were probably acquired independently in elasmarians from other large-sized taxa, such as hadrosauroids. Caudal vertebrae of the new species also show a unique combination of characters shared with other elasmarians, which are absent in previously known ornithopods. These features indicate that some elasmarians had a protonic tail posture, which is unknown in other ornithischians and was previously considered unique to derived titanosaurian sauropods. The shape of transverse processes and neural spines of caudal vertebrae indicate that at least some elasmarians had improved cursorial habilities, that were convergently acquired by selected theropod clades. [ABSTRACT FROM AUTHOR]

The “Marrón Emperador” ornamental stone is known for its characteristic deep brown colour filled with white spots and veins. It consists of a brecciated dolostone with different generations of calcite/dolomite veins and veinlets that represent repeated episodes of fracture opening and partial or complete cementation, which likely corresponds to individual stages of fluid expulsion. Mineralogical, petrographic and geochemical studies point to the formation of these rocks through brecciation, dolomitization and rapid cementation processes in an active tectonic regimen. The composition and textural features of the stratiform dolomite geobody point to a structurally controlled dolomitization model. The overall breccia geometry, breccia texture and vein characteristics are all consistent with a brecciation origin driven by hydraulic fracturing, with subsequent calcite precipitation in open space and partial solution replacement of clasts. A paragenetic sequence includes: (1) marine sedimentation of original tidal carbonate sediments; (2) early lithification and marine cementation; (3) burial diagenesis with early fracturation of limestones; (4) entrance of dolomitizing fluids through fractures causing pervasive dolomitization (brown dolostones) and dolomite cements (fracture-lining and saddle dolomites); (5) fracturation by hydraulic overpressure under an active tectonic regime; (6) calcite cementation (white veins and veinlets); and (7) uplift and meteoric diagenesis producing dedolomitization, karstification and local brecciation.

The results of integrated study of the Turonian–Coniacian sediments from the Abinsky district (Northwest Caucasus), which are represented by a rhythmic terrigenous-carbonate sequence, are discussed. The use of microfacial, X-ray diffraction, isotope, and micropaleontological analyses allowed us to reveal important changes in abiotic and biotic evolution during this interval. The peculiarities of carbonate sedimentation, as well as changes in the composition of foraminiferal assemblages, helped to establish fluctuations in the relative sea level, whereas isotopic studies assisted in defining climatic fluctuations. During the periods of accumulation of carbonate and clayey material, the area was occupied by a relatively deep-water open-sea basin with normal salinity. In the background of high temperatures, cooling pulses are also recorded within the studied interval. The position of the Turonian–Coniacian boundary in the section is revised. [ABSTRACT FROM AUTHOR]

A kilometre west of Pag Town on Pag Island, Croatia, within the Upper Cretaceous shallow-water carbonate succession, there is a large breccia body that has an irregular, quasi-circular shape and a subvertical-oblique position in relation to the bedding of the host rock. The breccia clasts and fragments consist almost entirely of the Upper Cretaceous host rock with only sporadic clasts of the Lower Eocene foraminiferal (alveolinid) limestones. In the brecciated body, there are three breccia types. 1) crackle breccia, 2) mosaic breccia, and 3) chaotic breccia. Based on the textural and structural characteristics of these types of breccia such as chaotic appearance and random fabric, very poorly sorted material, angular fragments, the composition reflecting only the host rock lithology, two genetic scenarios or concepts for the origin of Pag Town breccia body were considered, with observations supporting each of them. The first concept involves host rock dissolution resulting in a widened dissolution cavity into which wall and roof rocks progressively collapsed, and the second concept involves the collapse of voids produced by dilational fault displacement. A common prerequisite to both opposing scenarios is the existence of a subsurface cavity or void where the accumulation of rock clasts and fragments occurred. It is assumed that the timing of the cavity formation is related mainly to karstification during the Late Cretaceous-Early Eocene emersion phase or is related to dilational faulting during the Palaeogene Dinarides thrusting event. [ABSTRACT FROM AUTHOR]

The U–Pb (LA-ICP-MS) dating of detrital zircons from the Upper Cretaceous Derevyannye Gory Formation in the Novaya Sibir Island revealed that tuffites and tuffaceous sandstones contain zircons widely ranging in age from Archean to Upper Cretaceous. The weighted average age of the youngest zircon population is 88 ± 1.0 Ma, which constrains the lower age limit for sedimentation of the Derevyannye Gory Formation to the Coniacian. The clastic material was transported from the southwest and south to the north and northeast. The main source areas for the Upper Cretaceous sedimentary basin in the Novaya Sibir Island were the Upper Jurassic–Neocomian terrigenous sequences of the New Siberian–Chukotka fold area, lithotectonic complexes of the South Anyui suture, as well as the northern part of the Verkhoyansk–Kolyma fold area, and post-orogenic Aptian–Albian volcanic and plutonic rocks from the Lyakhov Islands and Svyatoi Nos Cape. Triassic terrigenous rocks of the northern Verkhoyansk region could serve as additional sources of clastics. It is also possible that the clastic material was partially supplied from the western Anjou Islands as a result of erosion of the Aptian–Lower Albian volcaniclastic–siliciclastic rocks. The Late Cretaceous zircon population is related to the Late Cretaceous explosive acid volcanism in the eastern Arctic region. [ABSTRACT FROM AUTHOR]

Abyssocythere and Dutoitella are extant benthic bathyal ostracod genera that evolved during Coniacian to Santonian/Campanian time from shallow-water progenitors around southeastern Africa. Their Late Cretaceous development was primarily in the South Atlantic, but during the Palaeogene they spread to the Indian and Pacific oceans. The establishment of the psychrosphere (late Eocene-mid-Oligocene) flushed populations of each genus from their central Atlantic cradles into the Pacific, presumably through the Panama Seaway, so that contemporaneous centres of evolution developed disjunct clades: A. trinidadensis and D. praesuhmi. The psychrospheric oceanic event defined temporal thermophyllic and cryophyllic populations of the two genera. Three Neogene ocean events appear to have affected several regionally-confined species, inter alia one of which entailed a counterflow migration of A. atlantica from the eastern Pacific back into the central Atlantic during the mid-Miocene. Modern distributions of Abyssocythere and Dutoitella are disjunct: in the Atlantic both genera occur south of ~40o N (Dutoitella), and equatorial areas (Abyssocythere); in the Indian Ocean both are confined to the southern part; and in the Pacific, Abyssocythere is restricted to central and north-eastern areas, and Dutoitella to the west and northwest. Neither genus evolved species that were more than para-cosmopolitan: A. diagrenona (South Atlantic-Indian; Eocene-Oligocene), A. trinidadensis complex (central Atlantic-NW Pacific; Oligocene-Miocene), D. crassinodosa complex (South Atlantic-Indian; Eocene), and D. praesuhmi (north and central Atlantic-central Pacific; Oligocene-Miocene). [ABSTRACT FROM AUTHOR]

A nearly complete and articulated dinosaur skeleton from the Upper Cretaceous (Cenomanian–Santonian) Bayinshire Formation at Bayshin Tsav locality in Gobi Desert (Mongolia) represents a juvenile hadrosauroid. This specimen is clustered with Gobihadros mongoliensis from the same formation and locality on 68% of the 304 most parsimonious trees produced by PAUP analysis. However, it is clearly different from Gobihadros by more derived dentition demonstrated by reduced marginal denticles and lack of accessory ridges on the tooth crown. The juvenile specimen additionally differs from Gobihadros by a triangular rostral process of parietals wedged between the frontals and much shorter postorbital process of jugal. This specimen may represent a second, previously unknown taxon of the Hadrosauroidea in the Bayinshire Formation. [ABSTRACT FROM AUTHOR]

Simple Summary: The use of new technologies applied to paleontological studies offers more detailed and attractive results each time. We describe a new genus and species of the relative rare beetle family Thanerocleridae (Cleroidea). Thanerosus antiquus gen. and sp. nov. is described as the fourth Cretaceous representative of Thanerocleridae. The set of characters observed in the new species suggests its basal position within the family and its relationship with the ancestral North American Zenodosus sanguineus, the single extant member of the subfamily Zenodosinae. The observance of some characters, including the mouthparts and details on the thorax's ventral side, was only possible after the 3D reconstruction of the fossil following its X-ray micro-CT scanning. This fact reinforces the effectiveness of this non-destructive technique for evolutionary studies through the use of fossils. We speculate on a wide diversification and distribution of this predatory family originally connected with an ecological community of saproxylic insects in the Cretaceous that were followed by habitat change and specialization of life inside fruiting bodies of fungi. Consequently, the family has not been recorded from the Cenozoic fossil collections yet and currently shows limited diversification. The predaceous beetle family Thanerocleridae is one of the smallest families of Cleroidea. It comprises only 36 extant species widespread on all continents. Three more species have been described from Cretaceous ambers of Myanmar and France. The fourth fossil representative of Thanerocleridae is described herein. Thanerosus antiquus gen. and sp. nov. is based on one fossil specimen preserved in an amber piece from Upper Cretaceous Kachin amber. The holotype was imaged using an X-ray micro-CT system to obtain high-quality 3D images. A phylogenetic analysis based on 33 morphological characters supports the placement of the new genus at the basal position in a tree of Thanerocleridae, in the vicinity of extant Zenodosus Wolcott and three extinct Mesozoic genera with which the new fossil shares open procoxal and mesocoxal cavities and transverse procoxae. We offer here a key to all extant and extinct genera in the family together with a complete list of all valid thaneroclerid taxa. [ABSTRACT FROM AUTHOR]

Analysis of foraminifera from the Igumale Formation of the southern Benue Trough was undertaken to determine the paleoecology and depositional environment of the sedimentary successions. The studied sections span a total stratigraphic thickness of 86.44 m comprising 85.34 m of drill core and 1.10 m outcrop section. The lithologies of the subsurface section are composed of massive to laminated grey shale with subordinate grey to cream limestone in the upper part of the section. The recorded foraminiferal microfauna consists mainly of benthic forms with few planktic taxa. A total of 17 species comprising 12 benthic and five planktic and representing 84 and 16%, respectively, of total foraminiferal abundance were identified. The benthic group is composed of 11 agglutinated species of Ammobaculites, Ammotium, and Haplophragmoides genera and one calcareous benthic species belonging to the genus Anomalinoides. The benthic microfauna is dominated by Ammobaculites and Ammotium. The planktic taxa are represented by Planoheterohelix, Muricohedbergella, and Pseudotextularia. The assemblages are characterized by low diversity and high dominance. Based on taxonomic composition, diversity indices, planktic/benthic foraminifera (P/B) ratio, and test morphotypes alongside sedimentological characteristics, brackish to shelf depositional environment with paleodepths ranging from shallow inner to middle neritic is deduced for the studied section of the formation. Bottom water oxygenation conditions varied intermittently between oxic and dysoxic with possible more oxic conditions towards the top of the borehole section. [ABSTRACT FROM AUTHOR]

The vertical ranges of inocerams, belemnites, ammonites, echinoids, sponges, and brachiopods from lithologically monotonous carbonate rocks have been studied in the Kommunar section. The results obtained in the study of macrofaunistic assemblages confirm and complement the benthic foraminifera research data of distinguished units of the middle–upper Turonian, Coniacian, lower and upper Santonian, and lower Campanian basal horizon. The stratigraphically full upper Coniacian–lower Santonian interval in the Kommunar section has been identified in the Volga region for the first time. The defined macro- and microfaunistic biostratigraphic units have been correlated and discussed. The Boreal–Tethyan magnetochronological correlation of the Santonian–Campanian makes it possible to conclude that the Santonian lower boundary in different regions differs by about a million years, which is comparable to the duration of the Santonian. [ABSTRACT FROM AUTHOR]

The last (IX) cervical vertebra from the Upper Cretaceous (Campanian) coastal marine deposits of Izhberda Quarry near the town of Orsk (Orenburg oblast) belonged to a large pterosaur with an estimated wingspan of 5.6 m. This vertebra is most similar to the IX cervical vertebra of a giant pterosaur Quetzalcoatlus sp. from the Maastrichtian of the United States in the relatively long centrum and the large hypapophysis and identified as Azhdarchidae indet. This finding is the first evidence of the existence of giant Azhdarchidae pterosaurs on the territory of Russia. [ABSTRACT FROM AUTHOR]

Here we report a new articulated skeleton of Yamaceratops dorngobiensis (MPC-D 100/553) from the Khugenetjavkhlant locality at the Shine Us Khudag (Javkhlant Formation, ?Santonian-Campanian) of the eastern Gobi Desert, Mongolia, which represents the first substantially complete skeleton and the first juvenile individual of this taxon. The specimen includes a nearly complete cranium and large portions of the vertebral column and appendicular skeleton. Its skull is about 2/3 the size of the holotype specimen, based on mandibular length. Its juvenile ontogenetic stage is confirmed by multiple indicators of skeletal and morphological immaturity known in ceratopsians, such as the long-grained surface texture on the long bones, the smooth external surface on the postorbital, open neurocentral sutures of all caudal vertebrae, a large orbit relative to the postorbital and jugal, the low angle of the lacrimal ventral ramus relative to the maxillary teeth row, narrow frontal, and straight ventral edge of the dentary. Osteohistological analysis of MPC-D 100/553 recovered three lines of arrested growth, implying around 3 years of age when it died, and verified this specimen’s immature ontogenetic stage. The specimen adds a new autapomorphy of Yamaceratops, the anteroventral margin of the fungiform dorsal end of the lacrimal being excluded from the antorbital fossa. Furthermore, it shows a unique combination of diagnostic features of some other basal neoceratopsians: the ventrally hooked rostral bone as in Aquilops americanus and very tall middle caudal neural spines about or more than four times as high as the centrum as in Koreaceratops hwaseongensis, Montanoceratops cerorhynchus, and Protoceratops andrewsi. The jugal with the subtemporal ramus deeper than the suborbital ramus as in the holotype specimen is also shared with A. americanus, Liaoceratops yanzigouensis, and juvenile P. andrewsi. Adding 38 new scorings into the recent comprehensive data matrix of basal Neoceratopsia and taking into account the ontogenetically variable characters recovered Y. dorngobiensis as the sister taxon to Euceratopsia (Leptoceratopsidae plus Coronosauria). A second phylogenetic analysis with another matrix for Ceratopsia also supported this position. The new phylogenetic position of Y. dorngobiensis is important in ceratopsian evolution, as this taxon represents one of the basalmost neoceratopsians with a broad, thin frill and hyper-elongated middle caudal neural spines while still being bipedal. [ABSTRACT FROM AUTHOR]

Field investigation, Microfacies analysis, and biostratigraphy have been carried out in the central parts of the Ionian Basin (Aetoloakarnania area, Western Greece) in order to decipher the depositional environments that developed during the accumulation of the Upper Cretaceous to Eocene carbonate succession. Three different Standard Microfacies types (SMF) have been observed, corresponding to two different depositional environments (Facies Zones or FZ) of a platform progradation. The three SMF types which occur in the study area during the Upper Cretaceous to Eocene are: 1. SMF 3 that includes mudstone/wackestone with planktic foraminifera and radiolaria, corresponding to toe-of-slope (FZ: 3), 2. SMF 4, which can be classified as polymict clast-supported microbreccia, indicating a toe-of-slope-slope environment (FZ: 4) and 3. SMF 5 which is characterized by allochthonous bioclastic breccia and components deriving from adjacent platforms and which reflects a slope environment. Microfacies analysis provided evidence of a change in the origin of sedimentary components and biota showing the transition from toe-of-slope to slope, as well as a change in organism distribution. [ABSTRACT FROM AUTHOR]

The aesthetic properties of ornamental stones, including colour, texture, and the presence or absence of discontinuities, are influential in their use and marketing. This is particularly critical in brecciated rocks such as the Marrón Emperador (ME) ornamental stone, a dark brown breccia dolostone (Upper Cretaceous, southeast Spain). ME shows a high chromatic and textural variability, which is one of its most appreciated commercial features. Through a petrographic, mineralogical, geochemical and colourimetric study of samples obtained from quarries, outcrops and/or drilling cores, several quality categories have been established, as well as the relationship between the aesthetic properties of ME ornamental stone with its compositional and textural factors. Three main types of breccia constitute the ME exploitable lithotect: crackle and mosaic packbreccias, and rubble floatbreccias. Breccia clasts are mainly composed of hypidiotopic-idiotopic medium- to coarsely-crystalline dolosparites, microcrystalline dolosparites and dolomicrites. Results show that diagenetic processes are mainly responsible for the colour of ME dolostones, revealing that the Sr content is a key factor. The darker brown dolomites always show a higher Sr content, where other typical chromophore elements in dolomites, such as Fe and Mn, do not present this correlation. This study provides evidence for the complexity of processes and factors that are responsible for aesthetic quality features in ornamental stones. [ABSTRACT FROM AUTHOR]

Bark beetles, fossil wood, Upper Cretaceous, wood-colonizing fungi, Araucariaceae, Ascomycota Here we describe a fungus colonizing wood of the extinct conifer I Agathoxylon i Hartig from the Upper Cretaceous Mzamba Formation of Pondoland (South Africa), and we draw comparisons with a blue stain fungus colonizing the wood of extant I Pinus strobus i . Keywords: Araucariaceae; Ascomycota; bark beetles; fossil wood; Upper Cretaceous; wood-colonizing fungi EN Araucariaceae Ascomycota bark beetles fossil wood Upper Cretaceous wood-colonizing fungi 1032 1037 6 01/10/22 20220201 NES 220201 Introduction Fossil fungi are frequently observed in association with fossil plants in a geological record that dates back over 400 Myr to the beginning of the Devonian Period (e.g. Strullu-Derrien I et al i ., 2014, 2018; Taylor I et al i ., 2015; Krings I et al i ., 2018; Krings & Harper, 2019). In most modern trees, two types of wood can be recognized: sapwood is the outer, pale-coloured wood, and heartwood the inner, mostly darker wood (Githiomi & Dougal, 2012). [Extracted from the article]

Aerosteon riocoloradensis represents one of the most complete megaraptorans yet discovered. This theropod comes from Anacleto Formation (Campanian) of Mendoza Province, Argentina. The aims of this contribution are: to present a detailed, bone by bone description of this specimen with figures of each bone; provide comparisons to other closely related theropods; revise the original assignation and diagnosis of such taxa. Three bones were re-assigned and almost all the autapomorphies of Aerosteon were modified. Features in the vertebral columns, which are shared with other megaraptorans, show that these theropods shared features with basal coelurosaurs. Anatomical Abbreviations ACDL: Anterior centrodiapophyseal lamina; CDF: Centrodiapophyseal fossa; CPAL: Centroparapophyseal lamina; CPRL: Centroprezygapophyseal lamina; CPRF: Centroprezygapophyseal fossa; CPR-CDF: Centroprezygapophyseal-centrodiapophyseal fossa; Hye: Hyposphene; Hym: Hypantrum; ILT: Intervertebral ligament tuberosity; IPOL: Infrapostzygapophysela lamina; IZL: Intrazygapophyseal lamina; PADL: Paradiapophyseal lamina; PAD-CDF: Paradiapophyseal-centrodiapophsyeal fossa; PCDL: Posterior centrodiapophyseal lamina; POEL: Postzygaepipophysela lamina; PODL: Postzygadiapophyseal lamina; POSF: Postspinal fossa; POCDF: Postzygapophsyeal-centrodiapophyseal fossa; Poz: Postzygapophysis; PRDL: Prezygadiapophyseal lamina; PRPAF: Prezygaparapophyseal fossa; PRPAL: Prezygaparapophyseal lamina; PRSF: Prespinal fossa; PRSL: Prespinal lamina; PRD-CDF: Prezygadiapophyseal-centrodiapophyseal fossa; PRD-PADF: Prezygadiapophyseal-paradiapophyseal fossa; PRD-PODF: Prezygadiapophyseal-postzygadiapophyseal fossa; PRCDF: Prezygapophyseal-centrodiapophyseal fossa; Prz: Prezygapophyses; SDF: Supradiapophsyeal fossa; SDL: Supradiapophyseal lamina; SPOF: Spinopostzygapophyseal fossa; SPOL: Spinopostzygapophyseal lamina; SPRF: Spinoprezygapophyseal fossa; SPRL: Spinoprezygapophyseal lamina; SR(number): Sacral rib; STP(number): Sacral transverse process [ABSTRACT FROM AUTHOR]

Bakhtiariella, a new genus of Larger Benthic Foraminifera is described from the upper Maastrichtian Tarbur Formation of Iran. The new taxon is characterised by a trochospirally coiled initial test part with angular chamber margins, later uncoiling and becoming rectilinear and presenting a coarse subepidermal network of horizontal and vertical partitions. Appearing as an extension of the subepidermal alveolar layer (exoskeleton), the pseudotriangular-shaped main partitions extend inwards and stretch downwards to the chamber floor where their arrangement is related to the inner margin of the central area with irregularly distributed pore-like foramina. Together with Persiacyclammina, which also displays such peculiar 'subepidermal septula', Bakhtiariella is included into the new family Bakhtiarellidae, and further compared with the Jurassic–Lower Cretaceous Hauraniidae. The new family gives further evidence for the diversification and pronounced endemism (Arabian Plate) of Larger Benthic Foraminifera within the final phase of the so-called Upper Cretaceous Global Community Maturation Cycle. This leads to the conclusion that both Persiacyclammina and Bakhtiariella can be considered 'Key Mesozoic Benthic Foraminifera of the Middle East'. [ABSTRACT FROM AUTHOR]

Titanosaurs were the predominant herbivores during the Late Cretaceous, inhabiting all continents. This clade was especially diverse in South America with some of the largest and smallest sauropod species known to date. Despite its diversity, the evolution of this clade is far from being well-known, although some recent analyses have begun to find some consensus in their results. Rinconsauria (defined as the least inclusive clade containing Rinconsaurus and Muyelensaurus) includes small titanosaurs and is considered as closely related to the lineage of giant titanosaurs, Lognkosauria (defined as the least inclusive clade containing Futalognkosaurus and Mendozasaurus), both being part of the recently named clade Colossosauria. The titanosaur Rinconsaurus caudamirus, from the Bajo de la Carpa Formation (Santonian), Río negro, Argentina, is represented by several axial and appendicular elements from at least four specimens. This taxon was only briefly described when it was named and most of its originally proposed autapomorphies are now recognized as having a more widespread distribution amongst titanosaurs. Herein we present a detailed osteological description of the axial skeleton and a revised diagnosis for this taxon that firmly establishes its validity. Based on comparisons with other titanosaurs, we found three new possible autapomorphies for the axial skeleton of Rinconsaurus, which added to its original combination of characters, endorsing this taxon as a valid genus. Besides, this revision of Rinconsaurus provides additional osteological data that will contribute to a better resolution of titanosaur phylogeny, contributing at the same time to our understanding of the clade Rinconsauria. [ABSTRACT FROM AUTHOR]

In the present study, selected the Kometan Formation (Late Turonian - Early Campanian) from the Dokan area, NE-Iraq. In this formation studied Ostracoda and identified fifteen open Ostracoda species belonging to ten genera (Bairdia, Bairdiacypris, Bythocypris, Bairdoppilata, Cavellina, Cypridina, Cytherella, Haplocytheridea, Pterygocythereis, and Paracypris). The goal of the present study is to identify Ostracoda species under polarizing microscopes for the first time in the Kometan Formation in the Dokan area. The Ostracoda assemblage such as Bairdia, Bairdiacypris, Cytherella, Cypridina, and Paracypris with foraminifera species Globotruncana linneiana, Globotruncanita stuartiformis, Marginotruncana schneeansi, and Dicarinella asymetrica indicate the Kometan Formation deposited in the deep marine environment. [ABSTRACT FROM AUTHOR]

This paper presents a new interpretation of the paleogeographic evolution of the northern side of the High Atlas Range of Marrakesh (Morocco) based on a tectonic, lithological, sedimentological, and paleontological description of the three outcropping Upper Cretaceous Formations: The Anou-Nfeg Formation, the Aït Abbes Formation, and the Chichaoua Formation. In biostratigraphical terms, these formations areas signed to the Coniacian, Santonian, and Maastrichtian, respectively, and record three tectonic phases responsible for the geodynamic evolution of this part of the High Atlas Range. These phases are confirmed by the vertical elevation of the earth's surface and the formation of some small restricted basins. A sedimentary pause corresponding to the Campanian has been recorded. Based on these findings, we conclude that these Formations were deposited in a confined environment influenced by the episodic marine incursions under a hot and humid climate. [ABSTRACT FROM AUTHOR]

The deep-lying Mesozoic and Paleogene deposits of the Middle Kura depression have significant resource potential. They are the main complexes in terms of prospectivity for oil and gas exploration. The lithological-facies characteristics of the host rocks, accumulation of which is tectonically conditioned, are among major indicators responsible for their oil and gas content. Based on actual core material from parametric, prospecting and exploratory wells, along with downhole logging data the marker horizons have been established for individual exploration areas within the depression. An overview of the lithostratigraphic features and thickness distribution of the Upper Cretaceous and Eocene deposits is given. Distribution of the fluid conducting strata, regional variation of their reservoir properties in buried structures of the Middle Kura depression is addressed as well. Within the study area a typical Upper Cretaceous section is comprised of three genetic rock types: sedimentary, igneous-sedimentary and igneous. The Eocene sediments are represented by shaly (Lower Eocene), terrigenous-carbonate (Middle Eocene) and terrigenous (Uppere Eocene) lithofacies. The regularities that have been revealed in lithofacies and thickness variation enabled highlighting the areas of highest subsidence and sedimentation, tracing basinal limits in Late Cretaceous and Eocene ages and depicting them on the maps presented. The compiled schematic maps clearly demonstrate the paleorelief in the study area at the close of Late Cretaceous and Paleogene times. Sections of the indicated sedimentary complexes contain effusive, carbonate, sandstone and siltstone reservoirs, exhibiting substantial occurrence and thickness, the latter having a marked trend to increasing toward the centerline of the Lower Kura depression. Thus, it is likely that the alteration in facies within the Upper Cretaceous and Eocene sections is closely interrelated with the breaks in sedimentation and erosions, favouring for formation of traps controlled by diverse screening features. At basin scale the major regionally persistent seal horizons are the Maykop shales of Oligocene-Lower Miocene age, which in a number of cases unconformably cover petroleum containing horizons. [ABSTRACT FROM AUTHOR]

The study area is located in Tang-e Bagh at Kuh-e Genu, approximately 69 km, northern Persian Gulf. The age relationships of Sarvak, Gurpi, and Pabdeh formations were unclear in the study area because of the low-resolution biostratigraphy. Therefore, 152 samples were collected. All samples contain well-preserved foraminifers that permit clarification of the age of these formations. Nine benthic species (5 genera) and sixty-eight planktonic foraminiferal species (29 genera) were identified that were arranged eleven biozones with high resolution of biostratigraphy. Biozone I corresponds to the total range of Orbitolina qatarica in the Mauddud Member of Sarvak Formation, suggesting the Cenomanian (middle Cenomanian) age. The biozone II is characterized by the total range of Dicarinella asymetrica in the basal part of Gurpi Formation, indicating the Santonian age. Therefore, there is a hiatus between the Sarvak and Gurpi formations that includes part of the Mauddud Member, the whole Ahmadi Member, and the Ilam Formation. This hiatus encompasses the late Cenomanian to Coniacian that is marked by a few meters of Fe-stained deposits in the Kuh-e Genu; the interval range zones III to VII as well as Abathomphalus mayaroensis zone VIII (TRZ) are present within the rest of Gurpi Formation and suggests the Campanian to Maastrichtian. The biozones IX-XI are present within the Pabdeh Formation that corresponds to a Not Zone and two interval range zones (P1b, P1c-P2), suggesting Danian. Based on microfacies, texture, and paleontological analysis, a deep-water environment suggests for Gurpi and Pabdeh formations and shallow marine conditions for Sarvak Formation. [ABSTRACT FROM AUTHOR]

Abstract Overbank deposits of submarine channels are typically thin‐bedded, fine‐grained and predominantly characterized by a series of sedimentary structures interpreted to record a relatively simple history of waning flow. Here, a new type of bedform indicative of Froude‐supercritical flow is reported from successions of thin‐bedded turbidites interpreted as channel overbank deposits in the Upper Cretaceous Rosario Formation, Baja California, Mexico. A link is demonstrated between the development of overbank deposits in the form of depositional terraces or internal levees and contemporaneously active sediment transport, bypass and deposition of coarser‐grained material in a channel. The overbank bedforms overlie an erosion surface and contain a suite of sedimentary structures indicative of initially Froude‐supercritical flow conditions and a progressive waning of flow strength. In some cases, a stacked repetition of facies is interpreted to record a rejuvenation of flow energy. The characteristic sedimentary sequence observed is as follows: (a) long wavelength, low amplitude erosional surface with superimposed scours; (b) antidune backsets; (c) upper stage plane‐parallel lamination; (d) subcritical climbing ripples; (e) supercritical climbing ripples; (f) lower stage planar laminated tops; (g) a sharp upper surface. The exact vertical sequence of sedimentary structures encountered varies depending on the point of observation with respect to the bedform crest and distance from the parent channel. The recognition of these distinctive bedforms allows for interpretation of sediment bypass and proximity to a channel thalweg. These bedforms have not hitherto been described and provide a further example of the range of flow processes operating in submarine channel–levee systems, which aids depositional environment interpretation in both subsurface and outcrop studies.

Studies of the paleopathology of the vertebrae provide an interesting, oblique approach to their paleobiology and even paleoethology. They tell us about possible ethological causes such as accidental blows with objects, social interactions within a group, and defense against predators, etc. There are numerous works on the anatomical and phylogenetic aspects of sauropod dinosaurs, and in recent years paleopathological studies have also increased. Here, we describe the injuries recorded in the caudal vertebrae of two indeterminate titanosaurids, and undertake a compilation and analysis of the pathological fossil record worldwide, focusing on the tails of sauropods. Two pathologies have been identified as present in the indeterminate titanosaurids under study: a possible case of spondyloarthropathy in MAU-Pv-LI-601, and a case of suppurative spinal osteomyelitis in MAU-Pv-LJ-472/1. Both titanosaurids are from Gondwana. In the world registry of pathologies associated with the tails of sauropod dinosaurs, it is observed that titanosaurs are the sauropods with the highest percentage of diagnosed pathologies (69% including the two new records from the province of Neuquén) and that all of these have been described in Gondwanan specimens.

Protoceratops andrewsi Granger and Gregory, 1923, is one of the most famous Upper Cretaceous horned dinosaurs of Central Asia. It was described from a separate skull found at Bayan Zag locality (Djadokhta formation, Mongolia). The holotype axial skeleton of this species is unknown, and its description appeared to be rather aggregated, capturing structural features of most ceratopsians from this locality. Polymorphism determined in this species is normally explained by gender, age and individual dimorphism. However, there is an opinion that P. andrewsi is a combined taxon that includes representatives of several species, but it is as yet difficult to determine the number of these species using the skull material. The study of the complete skeleton of P. andrewsi ZPAL Mg D-II/3 from the collection of Kozłowski Institute of Paleobiology, Polish Academy of Sciences (Warsaw, Poland), found at Bayan Zag, provided a solution to this problem. A detailed description of ZPAL Mg D-II/3 vertebrae and the study of its axial skeleton, taking into account its age and gender, revealed that this sample, most likely, was a large immature female. Comparative analysis of the vertebrae of this specimen with identical (of the same index number) vertebrae of specimens without associated skulls (PIN 3143/9 and PIN 3143/16) from the age-matched Tögrögiin Shiree locality (Mongolia), which are housed at Borissiak Paleontological Institute, Russian Academy of Sciences (Moscow, Russia), convinced us that they belong to the same morphotype. This makes it possible to diagnose P. andrewsi from vertebrae considering the age and gender of compared specimens. [ABSTRACT FROM AUTHOR]

Three species of echinoids Conulusmatesovi Moskvin, Echinocorys ovata (Leske) and Micraster corbovis Forbes from Turonian and Campanian deposits of Lower Volga region, with traces of the sublethal injuries in the tests, are described. Such injuries are of particular interest as they are not related to commensalism, predation, parasitism, or other effects of different animals, but are the result of a mechanical collision of echinoid tests with empty shells of inoceramids, which resulted in a foreign object being embedded and remaining in the tests but did not lead to their destruction or the death of the organism. Formation conditions and taphonomic aspects of the occurrences are considered. Possible mechanisms of sublethal injuries are analyzed. [ABSTRACT FROM AUTHOR]

The results of microfaunistic (benthic foraminifers) and magnetostratigraphic (paleomagnetic and petromagnetic) studies obtained in the lower part of the Upper Cretaceous deposits of the Kommunar section are presented. On the basis of the study of benthic foraminifers, the section consists of middle and upper Turonian, Coniacian, lower and upper Santonian, and basal horizon of the lower Campanian. In addition, all Coniacian zones and subzones of the East European Platform have been established. These data confirm the importance of the Kommunar section as a stratotype of the Volsk Formation (Coniacian of the Middle and Lower Volga region). In the Kommunar section, the Turonian and Coniacian are characterized by a normal polarity, and the Santonian and lower Campanian are characterized by a reversed polarity. [ABSTRACT FROM AUTHOR]

The tens of metres thick shell accumulations within the Cenomanian-Turonian strata of Western Carpathians enabled a complex study of ecological and geochemical proxies in relation to behavioural patterns of oyster Rhynchostreon suborbiculatum. Integration of geological and palaeobiological approaches enabled comparisons between one of the most famous fossil oyster species and several Recent bivalves. The analysis of grain size (Qz) and major oxides, together with taphonomic and population analysis, reveals a high-energy marginal-marine environment in the sedimentation area of the Orlové Sandstone. The life conditions of the association of bivalves, gastropods and polychaetes were influenced by the fluctuating influx of freshwater due to climatic changes that occurred during a dynamic period of the Late Cretaceous. A shift in the prominent control of biological production caused a massive increase in α-diversity, in conjunction with a change in the trophic structure of the studied system. The ecological responses of organismal association were also analogous to Recent representatives inhabiting marginal-marine environments. Size and allometric analyses of oysters forming monospecific assemblages show that their high density correlates with smaller shell sizes, indicating that intraspecific competition for food and space most intensified at times of the lowest salinity. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous Sudr Formation at Wadi El Dakhl, West Gulf of Suez (Northeast Egypt) has been described to analyze the facies and their cycles in conjunction with the influence of sea level and tectonics. The Sudr Formation (~ 130 m thick) is composed mainly of chalk and chalky limestone, with intercalations of argillaceous limestone and marl. It could be divided into two members; the Markha of the early–middle Campanian age and Abu Zenima of the late Campanian–Maastrichtian age. Biostratigraphically, nine planktonic foraminiferal zones have been recorded which encompass the studied section. Petrographic studies of the Sudr Formation led to identify five facies types; four carbonate facies and one marl facies. These facies have been deposited in the environmental conditions of an inner, middle, outer shelf, and open marine basinal setting. Two types of cyclicity have been identified: shallowing-upward and deepening-upward cycles which indicate a change in oscillation in the relative sea level. The comparison of the studied sea-level curve with the global curves of Haq et al. (Science 365:1156–1167, 1987) and Haq (Glob Planet Change 113:44–58, 2014) refer to general correspondence between them in addition to the clear effect of the tectonic events that influenced the obtained sea-level curve of the present study. Three pronounced tectonic events that impacted the deposition of the studied Sudr Formation were recorded. These tectonics were operated during the late Santonian, middle Campanian, and late Maastrichtian time interval. These tectonics are most probably related to the collision of African/Arabian and Eurasia Plates. [ABSTRACT FROM AUTHOR]

Borogovia gracilicrus is a small-bodied theropod dinosaur from the Maastrichtian (Upper Cretaceous) Nemegt Formation of southern Mongolia. The taxon is based on a single fragmentary specimen preserving only the distal part of the hindlimbs. The morphology of Borogovia shows a peculiar combination of features, some of which are traditionally considered troodontid synapomorphies and others which are unusual for Troodontidae but are shared with other maniraptoran clades. In particular, the second toe of B. gracilicrus differs from other troodontids in lacking some of the features which contribute to the specialized 'sickle-clawed' second toe, here termed the 'falciphoran condition', shared with dromaeosaurids and some other paravians, such as the strongly compressed and falciform ungual. Phylogeny reconstructions intended to explore the affinities of Borogovia consistently support its referral within a subclade of troodontids including all Late Cretaceous taxa. The placement of Borogovia is not significantly affected by its unusual combinations of hindlimb features or by the homoplasy of the elements forming the falciphoran condition. Borogovia is supported as a valid taxon and is distinct from the other Nemegt troodontids, Tochisaurus and Zanabazar. The lack of a falciform ungual, and the distinctive morphology of the second toe in B. gracilicrus are interpreted as a derived specialization among Troodontidae and not as retention of the plesiomorphic condition of non-paravian theropods. [ABSTRACT FROM AUTHOR]

The early Cenomanian crippsi Event comprises a 1–3-m-thick interval characterised by mass occurrences of the early Cenomanian inoceramid Gnesioceramus crippsi, identified in the uppermost Sharpeiceras schlueteri Subzone (lower lower Cenomanian Mantelliceras mantelli Zone), below an interregional sequence boundary (SB Ce 1). At Lüneburg, the event is characterised by densely packed, very large, disc-like valves of G. crippsi. Taphonomy as well as bio- and microfacies suggest an event formation in a deeper shelf setting below the storm-wave base as primary biogenic concentration, the inoceramids living as recumbent forms on a soft substrate in dense populations. When tracked between basins, the stratigraphic pattern of the crippsi Event suggests a moderately prolonged phase (< 100 kyr) of increased shell production with rapid deposition aiding in preserving the shell-rich event strata. Towards the basin margins, it grades into storm wave-reworked bioclastic concentrations. The crippsi Event formed by an interregional population bloom and provides, as an proliferation epibole, an important marker for intra- and interbasinal correlation. The first record of G. mowriensis within the crippsi Event at Lüneburg, hitherto endemic to the US Western Interior Seaway, and the occurrence of the ammonite Metengonoceras teigenense, likewise an endemic North American faunal element, from the level of the crippsi Event in northern France indicate faunal exchange between the New and Old worlds during the early Cenomanian. This faunal dispersal and contemporaneous occurrence of warm-water biofacies in Western Europe during the early Cenomanian is explained by the existence of a perpetual NE-directed current transporting warm surface waters from the Gulf of Mexico towards Europe. The occurrence of short-lived M. teigenense in France allows for the calibration of the uppermost schlueteri Subzone of the mantelli Zone in Europe to the lowermost Neogastroplites muelleri Zone in North America and to assign an age of ~ 98.6–98.7 Ma to the crippsi Event. [ABSTRACT FROM AUTHOR]

Modern hydrothermal vent communities are based on chemosynthesis by microbial primary producers. Molecular phylogenetic divergence estimates indicate that many of the dominant vent taxa arose during the Cenozoic and Cretaceous; however, the fossil record of vent communities from these time periods is poor. One occurrence of such Cretaceous vent communities pertains to six volcanogenic massive sulphide deposits in the Troodos ophiolite of Cyprus. These deposits represent hydrothermal activity on deep (2500–5000 m) arc‐related spreading ridge(s) in the Neotethyan Ocean over several million years during the late Cenomanian and earliest Turonian. The Cyprus vent communities consist of worm tubes, representing possible vestimentiferans and serpulids, together with a moderate diversity of abyssochrysoid gastropods, belonging to eight new species (Desbruyeresiakinousaensis sp. nov., Desbruyeresiamemiensis sp. nov., Desbruyeresiakambiaensis sp. nov., Hokkaidoconchamorisseaui sp. nov., Ascheriacanni sp. nov., Cyprioconcharobertsoni gen. et sp. nov., Paskentanaxenophontosi sp. nov. and Paskentanadixoni sp. nov.) in five genera and three families; none of the species is shared between vent sites. A single gaudryceratid ammonite from one of the vent sites most likely represents a water‐logged shell that sank from surface waters. The gastropod fauna contains the first representatives of the genera Desbruyeresia, Hokkaidoconcha, Ascheria and Paskentana from hydrothermal vents, and also the youngest representative of the last‐named genus in any environment. The Cypriot vent communities share tube worms with slightly older (Cenomanian) and younger (Turonian–Santonian) vent communities elsewhere in the western part of the Neotethyan Ocean. [ABSTRACT FROM AUTHOR]