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For the first time, a complete study of sauropod trackways has been carried out in the lower part of the Djoua series in the In Amenas region (southeastern Algeria). Several locomotion tracks have been discovered in this area. In the present work, we report the discovery of sauropod tracks exposed on a bedding surface of the Lower Formation attributed to the early Cenomanian that we assign to cf. Brontopodus isp. The tracks are located in two different areas approximately 2 km apart and are oriented N00° and N330° at the first and second sites, respectively. These tracks were formed when dinosaurs crossed an emergent or lightly submerged river plain. At the second site, trackways show several tracks generated by sauropods. They are sub-parallel in orientation and provide the first ichnological evidence of gregarious behavior in Cretaceous sauropods in Africa. [ABSTRACT FROM AUTHOR]

Current investigations into the Albian–Cenomanian sedimentary record within the Western Interior have identified multiple complex tectono‐sedimentary process–response systems during the ongoing evolution of North America. One key sedimentary succession, the upper Cedar Mountain Formation (Short Canyon Member and Mussentuchit Member), has historically been linked to various regionally and continentally significant tectonic events, including Sevier fold‐and‐thrust deformation. However, the linkage between the Short Canyon Member and active Sevier tectonism has been unclear due to a lack of high‐precision age constraints. To establish temporal context, this study compares maximum depositional ages from detrital zircons recovered from the Short Canyon Member with that of a modified Bayesian age stratigraphic model (top‐down) to infer that the Short Canyon Member was deposited at ca 100 Ma, penecontemporaneous with rejuvenated thrusting across Utah [Pavant (Pahvant), Iron Springs and Nebo thrusts]. These also indicate a short depositional hiatus with the lowermost portion of the overlying Mussentuchit Member. The Short Canyon Member and Mussentuchit Member preserve markedly different sedimentary successions, with the Short Canyon Member interpreted to be composed of para‐autochthonous orogen–transverse (across the Sevier highlands) clastics deposited within a series of stacked distributive fluvial fans. Meanwhile, the muddy paralic Mussentuchit Member was a mix of orogen–transverse (Sevier highlands and Cordilleran Arc) and orogen–parallel basinal sediments and suspension settling fines within the developing collisional foredeep. However, the informally named last chance sandstone (middle sandstone of the Mussentuchit Member) is identified as an orogen–transverse sandy debris flow originating from the Sevier highlands, similar to the underlying Short Canyon Member. During this phase of landscape evolution, the Short Canyon Member – Mussentuchit Member depocentre was a sedimentary conduit system that would fertilize the Western Interior Seaway with ash‐rich sediments. These volcaniclastic contributions, along with penecontemporaneous deposits across the western coastal margin of the Western Interior Seaway, eventually would have lowered oxygen content and resulted in a contributing antecedent trigger for the Cenomanian–Turonian transition Oceanic Anoxic Event 2. [ABSTRACT FROM AUTHOR]

For much of the pelagic sedimentary record, time control is limited to the resolution of precession cycles (ca 20 kyr): the Milankovitch parameter that forms the most detailed metronome for the Cenozoic and Mesozoic Eras. The influence of precession is often detected in lithological alternations, where the duration represented by individual lithologies is not well constrained. Here the novel technique of extraterrestrial helium abundance (3HeET) is used to investigate the sedimentation dynamics and palaeoceanography within individual precessional cycles. High‐resolution 3HeET timescales were produced for four precession cycles from the rhythmically bedded Scaglia Bianca Formation, a sequence of Upper Cretaceous (Cenomanian) deep‐marine pelagic limestones from central Italy that are well characterized by cyclostratigraphy. Using 3HeET concentrations as a proxy for sedimentation rate allows instantaneous sedimentation rates and organic‐carbon mass accumulation rates to be calculated for each bed within a precession cycle. Eccentricity is known to modulate the amplitude of precession forcing, and precession cycles deposited under eccentricity maxima and minima were selected for comparison. Lithological changes through these chert–(black shale)–limestone cycles are explained using the concept of 'palaeoenvironmental thresholds'; these timescale calculations indicate that when the amplitude of precessional insolation forcing was greatest (at eccentricity maxima) the palaeoenvironmental system spent longer in the more nutrient‐rich environment under which siliceous and organic‐rich sediments were deposited, reflecting increased time spent above a 'threshold' insolation level. Estimates of primary productivity are relatively elevated for organic‐rich beds. An increase in the flux of terrestrial helium (4Heterr) during the deposition of cherts may have been coincident with an increase in terrestrially derived nutrients. The presented results indicate great potential for the use of 3HeET to understand past oceanographic, climatic and sedimentological processes at high temporal resolution. [ABSTRACT FROM AUTHOR]

An articulated group of skeletal elements comprising a sacrum, both ilia and a first caudal vertebra, plus an isolated tooth found in immediate proximity to the bones, from the lower Cenomanian Chalk at Saint-Jouin-Bruneval (Seine-Maritime, Normandy, France) is described and attributed to a new genus and species of abelisaurid theropod, Caletodraco cottardi, on the basis of several characters of the sacrum and pelvis. The peculiar shape of the transverse process of the first caudal vertebra shows that Caletodraco cottardi differs from majungasaurine abelisaurids previously described from Europe, such as Arcovenator escotae, and belongs to the Furileusauria, a group of derived abelisaurids hitherto recognized only from South America. The presence of a furileusaurian abelisaurid in the Cenomanian of Normandy suggests that the biogeographical history of the Abelisauridae in Europe was more complex than hitherto admitted. Several previously described European abelisaurids, such as the Albian Genusaurus sisteronis, may in fact belong to the Furileusauria. [ABSTRACT FROM AUTHOR]

The Cenomanian deposits of the Eastern Saharan Atlas are characterised by gypsum-dominated series interpreted as coastal sabkha deposits, indicating low-latitude, and tropical to subtropical settings. The evaporitic conditions are interrupted by rapid marine ingressions allowed the deposition of carbonate beds. In the Djebel Ousigna section, fine sandy limestone bed shows abundant burrows of Macaronichnus. These traces indicate the upper shoreface–foreshore contact, affected by storm events, which show similarities with recent huge tsunami waves that facilitated the proliferation of Travisia polychaete populations (Macaronichnus tracemaker). This Macaronichnus -suite represents the most proximal marine setting during a regressive phase. Also, this unique occurrence of Macaronichnus in the North African Cenomanian low-latitude, subtropical to tropical evaporites is interpreted as related to upwelling of cold nutrient rich-waters. The latter seemingly challenge the view that this trace fossil is restricted to colder climatic zones. From an ethological viewpoint, studied Macaronichnus specimens are considered to be a sequorichnial trace (exploratory behaviour) produced by polychaete annelids. [ABSTRACT FROM AUTHOR]

The lower Cenomanian ammonite Sharpeiceras cf. laticlavium (Sharpe, 1855) and the middle Cenomanian ammonite Calycoceras (Gentoniceras) gentoni (Brongniart, 1822) were found for the first time in the Selbuhra Mountain section in Southwestern Crimea. These finds allow us to complete the biostratigraphic subdivision of the Cenomanian in Southwestern Crimea and to expand our understanding of the distribution of these ammonites. [ABSTRACT FROM AUTHOR]

Paper shows the information about the geological and geophysical exploration of Tambeyskoye natural gas field located in the north of the Yamal Peninsula. The problems with mapping of natural gas deposits in Cretaceous and Jurassic formations are described. The results of formation thickness analysis are presented in order to explain the reasons for the unprecedented concentration of separate natural gas accumulations and the heterogeneous saturation of massive reservoirs in Cretaceous formations. The method of paleotectonic analysis is briefly described, the initial data are reported. Structural and isopach maps are presented. Structural elements and their evolution in Jurassic and Cretaceous time are presented. It was concluded that different structural elements of the work area transformed quite independently until the end of Cenomanian. The modern shape of North Tambey uplift was forming during the Neogene to Quarter age. Natural gas bearing reservoirs in Jurassic formation with the overpressure were reported. The young age of the North Tambey uplift, the unprecedented concentration of separate natural gas accumulations, the and the heterogeneous saturation of massive reservoirs in Cretaceous formations, overpressure in Jurassic formation – all these facts show that the Tambeyskoye natural gas field is under active gas accumulation. Hydrocarbon gases coming from deep Jurassic formations and it was not enough time for gas accumulations to be distributed over the reservoirs of Cretaceous.

Simple Summary: An increasing number of fossil specimens of planthoppers from Burmese amber are being described. Few of them belong to extant families. Here, we described two new fossil species of Pentacarinus: P. maculosus sp. nov. and P. tenebrosus sp. nov. in the tribe Acrotiarini in the extant family Cixiidae, from Kachin state of northern Myanmar. A revised diagnosis for the genus and a key to species identification are also provided. Two new species, Pentacarinus maculosus sp. nov. and Pentacarinus tenebrosus sp. nov., from Burmese amber are described. Alongside the type species P. kachinensis already described, they are easily distinguishable by the tegmina patterns. The diagnosis of the genus Pentacarinus is amended, notably with fusion of Pcu + A1 distad of forking CuA, the fork ScP + R approximately close to basal 1/5 of tegmen, basad of forking CuA, and only one transverse veinlet ir between RP and RA on forewings. Additionally, a key to these three species of Pentacarinus is provided. [ABSTRACT FROM AUTHOR]

Simple Summary: The Bethylidae, dubbed "flat wasps" because of the general aspect of their bodies, are important components of past and present entomofauna. Currently comprising 3000 species, the Bethylidae are also very diverse in the fossil record. In this study, we present the first Cretaceous record of the Epyrinae, named Hukawngepyris setosus, from the rich mid-Cretaceous (ca. 100 Ma) Myanmar amber. The newly proposed binomial name is a reference to the Hukawng Valley, where the specimen was collected, and to the conspicuous setation of the species. Describing this fossil adds valuable insights to our understanding of Cretaceous Bethylidae, as it represents the oldest record of the second largest subfamily, which was very common during the Cenozoic. This hints at the need for further exploration of various Cretaceous deposits to enhance our understanding of their past distribution and early occurrences. The Epyrinae are the second largest subfamily of Bethylidae and the most diverse in the fossil record. However, although six of the nine bethylid subfamilies are known during the Cretaceous (either as compression or amber fossils), the Epyrinae were hitherto unknown before the lower Eocene. In this contribution, we report the discovery of the oldest member of this group, based on a female specimen from the early Cenomanian amber of Kachin, Myanmar. We describe and illustrate a new genus and species, Hukawngepyris setosus gen. et sp. nov. The new genus is compared with the other epyrine genera and characterized by a unique combination of characters not known in the subfamily. Hukawngepyris setosus gen. et sp. nov. is especially unique in the configuration of the forewing venation, with a complete 2r-rs&Rs vein, curved towards the anterior wing margin, and the presence of three proximal and three distal hamuli. The key to the genera of Epyrinae is accommodated to include the newly erected genus. [ABSTRACT FROM AUTHOR]

The Komsomolsk tin-ore district is located along the Miao-Chan Ridge in the Middle Amur River area (Khabarovsk krai) within the Badzhal accretionary terrane of the Sikhote-Alin orogenic belt. This work presents new results of U–Pb zircon dating of tonalite from the Miao-Chan complex of the Silinka granite pluton (99.7 ± 1.1 Ma) and rhyolites of the lower part of the Kholdami Formation (98.4 ± 1.0 and 98.7 ± 1.2 Ma) from the northeastern part of the Komsomolsk district. The geochemical characteristics of the rocks studied show that granitoids of the Miao-Chan complex are I-type rocks and that synchronous rhyolites of the Kholdami Formation are highly aluminous and correspond to S-type rocks. New data on the composition and early Cenomanian age of the rocks make it possible to consider the ore-magmatic system of the Komsomolsk ore district as part of the previously identified Albian–Cenomanian igneous province of Pacific Asia. [ABSTRACT FROM AUTHOR]

Simple Summary: An increasing number of fossil planthoppers from Burmese ambers are regularly newly described, yet few belong to extant families. In this study, we describe new fossil taxa in the family Achilidae: Niryasaburnia nigrutomia sp. nov. and Sinuovenaxius kachinensis gen. et sp. nov. Additionally, we propose the establishment of a new tribe, Niryasaburniini trib. nov., to accommodate these two genera. A key for identifying tribes within the Myconinae subfamily is provided. A new species Niryasaburnia nigrutomia sp. nov. of the planthopper family Achilidae from Burmese amber collected from Hukawng Valley (Tanai) of northern Myanmar, is described, notably based on forewing pattern coloration and metatibiotarsal teeth conformation. A new fossil genus with its type species Sinuovenaxius kachinensis gen. et sp. nov. is also described. The tribe Niryasaburniini trib. nov. is established to include Niryasaburnia Szwedo, 2004, and Sinuovenaxius gen. nov., based on a unique combination of characters, of which the following states are particularly notable: head with compound eyes around half the length of pronotum, late forking of ScP+R and CuA after the fusion of Pcu+A1 on the forewing, apical teeth of metatarsomeres I and II both with subapical platellar sensilla, and a unique hindwing pattern with simple RP and biforked MP, CuA with two terminals only, and with A2 simple, reaching the posterior wing margin. The hindwing venation of this new tribe with RP with only one terminal and both MP and CuA with two terminals is unique in Achilidae. [ABSTRACT FROM AUTHOR]

The Mishrif Formation (Cenomanian -E Turonian) is one of the most important geological formations in the Middle East and Iraq because it contains enormous petroleum accumulations. It is considered to be the first reservoir in the region, and is still being studied because of its economic significance. The carbonate of the Mishrif Formation derives from a variety of depositional settings, including mid-ramp, shoal, lagoon, and intertidal. The five main microfacies discussed in this paper are wackestone, packstone, grainstone, floatstone, and bindstone. The most frequent fossilised components found in the Mishrif Formation are rudists, benthic foraminifera, echinoderms, burrows molluscs, and algae. According to the microfacies and analysed wireline log data, the sequence stratigraphy of the studied formation is composed of two regression cycles. Five parasequences of transgressive–regressive cycles make up the depositional sequence of the Mishrif Formation. The standard depositional environments seem to demonstrate a gradual regression, beginning with a short period of the outer ramp, then a steady period of the mid-ramp, and ending in the intertidal environment. Additionally, the study recorded two regional maximum flooding surfaces: K-135 and K-140. The former is present in the lowermost part of the formation, while the other lies in the middle. This study shows a close relationship between facies (environments) and hydrocarbon accumulation. The increased accumulation focuses on the lower part of the studied formation, and seems to be lower in the upper part of the formation as a result of changes in the environment of deposition.

Three specimens of Pelecinidae preserved in mid-Cretaceous Burmese amber from Northern Myanmar were examined and described. Ampluspelecinus robustus gen. et sp. nov. and Eopelecinus diminutivum sp. nov. of Pelecinidae from mid-Cretaceous Burmese amber are characterized by the shape and size of their mesosoma, metasoma, and wing venation. Ampluspelecinus robustus is distinguished from other pelecinid species by its length ratio of metasomal segments, 2r-rs in the forewing forming an "X" pattern, with Rs2 extending approximately two-thirds toward the forewing apex. E. diminutivum sp. nov. is distinguished by its metasomal length ratio and swollen fore, mid, and hind femora. In addition, both female and male specimens are described from amber, which is unusual because male pelecinid wasps, both extant and extinct, are relatively rare. The male specimen is the smallest Pelenicidae wasp reported to date. [ABSTRACT FROM AUTHOR]

Carentonosaurus soaresi was recently described in the uppermost middle Cenomanian (Upper Cretaceous) of Casais dos Carecos (Coimbra, western Portugal) based on a diverse set of new material (cervical and dorsal vertebrae) of the Pythonomorpha lizard. The main morphological characteristics observed in the vertebrae used for the diagnosis of this species are the presence of distinct lateral and subcentral foramina, highly laterally projected paradiapophyses beyond the prezygapophyses, a low subrectangular neural spine ornamented with longitudinal grooves, and dorsal vertebrae displaying a sagittal furrow along the ventral surface. Additional diagnostic details observed both in new material and the previously studied vertebrae are described herein, such as the presence of keels in the zygantrum and zygosphene. These and other important morphological characteristics present in the species soaresi are absent in the genotype Carentonosaurus mineaui and in other known Squamata, allowing for the definition of the new genus Segurasaurus. [ABSTRACT FROM AUTHOR]

Hitherto, only two species of the thysanopteran suborder Terebrantia have been reported from mid-Cretaceous Kachin amber (Myanmar). This is here expanded through the discovery of two new genera and species, described and figured as Parallelothrips separatus gen. et sp. nov. and Didymothrips abdominalis gen. et sp. nov., both of the family Stenurothripidae. Both taxa have key apomorphies of the Stenurothripidae, allowing for a confident assignment as to family. Both species have characteristic comb-like anteromarginal setae, which are discussed along with structural differences between the two sexes. Cycad pollen was found on the thrips’ bodies, providing further evidence that Thysanoptera were pollinators of gymnosperms during the mid-Cretaceous. [ABSTRACT FROM AUTHOR]

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A new genus of the Nezzazatidae is here introduced as Simplorabanitina simplex gen. et sp. nov. from the Cenomanian Sarvak Formation of south-western Iran. The main architectural constraints used to discriminate the new taxon from its close ally Rabanitina Smout lies in the complete lack of skeletal elements collectively called the ‘median plate’ or ‘complex longitudinal plate’, and by the occurrence of pseudo-keriotheca characterising the chamber wall. The new occurrence increases the number of species of Nezzazatidae throughout the shallow-water carbonate platforms of the Arabian Plate prior to the extinction related to the Oceanic Anoxic Event 2 of the Cenomanian-Turonian boundary, indicating high diversity. Unlike some other Cenomanian Nezzazatidae that have been commonly found from Mexico to the Middle East, the biogeographic affinity of Simplorabanitina n. gen. seems to be restricted to the Arabian Plate and perhaps might also be found in the coeval successions of NE Africa. [ABSTRACT FROM AUTHOR]

In order to better constrain the Mesozoic-Cenozoic evolution of the Precambrian Hoggar shield, a paleomagnetic study, combined with detailed fieldwork, was carried out to date its detrital local cover, the Serouenout Formation. Thermal demagnetization yields, only in a few samples, the characteristic remanent magnetization carried by hematite. Post-tilting remagnetization was obtained in sites located along a fault affected by intense fluids circulation. The paleomagnetic directions recorded at seven widespread other sites are on the contrary associated with a positive fold test. It provides a relatively well-defined paleomagnetic pole (A95 = 4.1°), sufficient to estimate the age of the Serouenout Formation. The comparison of this pole with the reference curve of Africa suggests two possible age windows, Triassic and Upper Cretaceous-Lower Paleocene, while the discovery in the uppermost levels of the Serouenout Formation of a fern-rich level with Weichselia reticulata (Bathonian to Cenomanian; Blanco-Moreno et al., 2018) imposes a deposition during the Cenomanian. The presence of a detrital formation at least 350 m thick, with a basal conglomerate containing large pebbles, implies the existence, during this time period, of a tectonic event that generated differential uplift. In addition, structural observations indicate that the Serouenout Formation recorded later brittle tectonics, dominated by a network of vertical N–S dextral faults. The horizontal displacement generated by one well-developed fault has been estimated to be at least 1 km. This activity is related to the known Alpine reactivations of the N–S Pan-African mega-structures, which are still at the origin of the current intraplate seismicity. [ABSTRACT FROM AUTHOR]

Several disarticulated fish scales and a vertebral centrum were collected from the uppermost middle to lowermost upper Cenomanian beds of the vertebrate fossil site of Casais dos Carecos (Baixo Mondego region, Coimbra, West Portugal), corresponding to shallow carbonate and mixed facies ("Unit B") of the Tentúgal Formation. The taphonomic preservation of these remains is adequate for their detailed taxonomical study. The scales are diagnosable for the species Obaichthys africanus Grande, as each one has a strong spine protruding from the middle of the posterior border in a rostrocaudal direction, a dorsoventral peg and socket, and a small anterodorsal process for articulation of adjacent scales. The sculpture with ganoid ridges and grooves distinguishes the studied remains from those of O. decoratus Wenz and Brito, which display rounded tubercles. The isolated Lepisosteoidea centrum is tentatively attributed to O. africanus as well, as it was found together with the scales, and no other compatible remains were found in the site. The fish material reported here constitutes the first record of O. africanus in the Baixo Mondego region and northern ranges of the Albian–Turonian West Portuguese Carbonate Platform, as well as in the uppermost middle to basal upper Cenomanian of Portugal. [ABSTRACT FROM AUTHOR]

New material of Roveacrinidae from the Middle-Upper Cenomanian Grey Chalk Group of the Kent coast (Folkestone-Dover) is described. The fauna includes 10 taxa, including a new genus and species (Dubrisicrinus minutus) and three new species (Styracocrinus shakespearensis, Roveacrinus aboudaensis and Dentatocrinus serratus). The biostratigraphical significance of roveacrinid faunas is placed in a global context, and it is demonstrated that the roveacrinid zone CeR5, previously recorded only from Morocco, is approximately equivalent to the upper Middle Cenomanian Acanthoceras jukesbrownei ammonite Zone, and zone CeR6 - to the Calycoceras guerangeri ammonite Zone. The new material also provides novel information on the cup structure of roveacrinids, which is reviewed and placed in a phylogenetic context. [ABSTRACT FROM AUTHOR]

The taxonomy of representatives of the genus Oscillopha Malchus, 1990 from the Aptian, Albian, and Cenomanian of the southwestern spurs of the Gissar Ridge (southeastern Turkmenistan) is revised. Issues of taxonomy of Mesozoic Lopha-like oysters are discussed. The diagnoses and composition of the family Arctostreidae Vialov, 1983, subfamily Arctostreinae Vialov, 1983, and genus Oscillopha Malchus, 1990 are specified. The genus Oscillopha is represented by the species O. eos (Coquand, 1869) in the Aptian and Albian and O. dichotoma (Bayle, 1849) in the Cenomanian. [ABSTRACT FROM AUTHOR]

Two new species, Pentacarinus maculosus sp. nov. and Pentacarinus tenebrosus sp. nov., from Burmese amber are described. Alongside the type species P. kachinensis already described, they are easily distinguishable by the tegmina patterns. The diagnosis of the genus Pentacarinus is amended, notably with fusion of Pcu + A1 distad of forking CuA, the fork ScP + R approximately close to basal 1/5 of tegmen, basad of forking CuA, and only one transverse veinlet ir between RP and RA on forewings. Additionally, a key to these three species of Pentacarinus is provided.

The Epyrinae are the second largest subfamily of Bethylidae and the most diverse in the fossil record. However, although six of the nine bethylid subfamilies are known during the Cretaceous (either as compression or amber fossils), the Epyrinae were hitherto unknown before the lower Eocene. In this contribution, we report the discovery of the oldest member of this group, based on a female specimen from the early Cenomanian amber of Kachin, Myanmar. We describe and illustrate a new genus and species, Hukawngepyris setosus gen. et sp. nov. The new genus is compared with the other epyrine genera and characterized by a unique combination of characters not known in the subfamily. Hukawngepyris setosus gen. et sp. nov. is especially unique in the configuration of the forewing venation, with a complete 2r-rs&Rs vein, curved towards the anterior wing margin, and the presence of three proximal and three distal hamuli. The key to the genera of Epyrinae is accommodated to include the newly erected genus.

A new species Niryasaburnia nigrutomia sp. nov. of the planthopper family Achilidae from Burmese amber collected from Hukawng Valley (Tanai) of northern Myanmar, is described, notably based on forewing pattern coloration and metatibiotarsal teeth conformation. A new fossil genus with its type species Sinuovenaxius kachinensis gen. et sp. nov. is also described. The tribe Niryasaburniini trib. nov. is established to include Niryasaburnia Szwedo, 2004, and Sinuovenaxius gen. nov., based on a unique combination of characters, of which the following states are particularly notable: head with compound eyes around half the length of pronotum, late forking of ScP+R and CuA after the fusion of Pcu+A1 on the forewing, apical teeth of metatarsomeres I and II both with subapical platellar sensilla, and a unique hindwing pattern with simple RP and biforked MP, CuA with two terminals only, and with A2 simple, reaching the posterior wing margin. The hindwing venation of this new tribe with RP with only one terminal and both MP and CuA with two terminals is unique in Achilidae.

Basin margin evolution of rift basins is not always well constrained. In the northeastern margin of the Basque-Cantabrian Basin, a revision of a carbonate succession permits deciphering the transition from synto post-rift phases in the poorly studied northwestern margin of the Bortziriak-Cinco Villas massif. The sedimentological analysis shows three main lithofacies, attributed to a shallow-marine, non-rimmed carbonate platform. On the other hand, biostratigraphic analysis based on the presence of Caprina adversa rudist indicates a Cenomanian age for the succession. Thus, this study illustrates the existence of a Cenomanian shallow-marine carbonate platform unconformably overlying the Palaeozoic massif. This platform development was the result of a generalized transgression during the early post-rift stage.

Only few candidates of Mesozoic fishes with a similar body plan and ecological niche to the modern billfishes are suggested as their analogues. Several specimens were recovered from Cenomanian deposits in Germany and Lebanon and display a billfish-like fusiform body with elongated premaxillae. They are found close to the plethodids and show a unique combination of characters (rostrum pointed and extremely elongated, double articular head of the quadrate, anteroposteriorly elongated abdominal centra indicating a slender body and different types of scales on the body) allowing their inclusion in a new genus. Two ‘Protosphyraena’ species are also assigned to this new genus. This fish can be considered as an ecological analogue to the extant xiphioids sharing their feeding habits. This fish was abundant and roamed, as an apex predator, the Central Tethys and the Boreal realms during the Cenomanian.

We document diverse and well-preserved dinoflagellate cyst assemblages from Cretaceous successions in the Kullemölla 1 drill core (640.0 m–590.0 m), Vomb Trough, southern Sweden. Palynology reveals a nearshore marine environment. Dinoflagellate index taxa indicate an Albian to Coniacian age, thus spanning the Early–Late Cretaceous boundary. The lower part of the core is Albian, based on the presence of the index dinocyst taxa Pareodinia and Callaiosphaeridium asymmetricum. The First Appearance Datum (FAD) of Oligosphaeridium prolixispinosum, together with the presence of Achomosphaera ramulifera, Heterosphaeridium difficile and Oligosphaeridium pulcherrimum, reveals a Cenomanian age for the interval 635– m–617 m. The Turonian interval is characterized by an increase in the dinocysts Chatangiella spectabilis and Florentinia spp., in combination with the FAD of Senoniasphaera rotundata, whereas the youngest samples are dated to the Coniacian as defined by the appearance of Glaphyrocysta sp. We show that Cenomanian and Turonian strata are indeed represented by a relatively condensed section between 635 m and 612 m in the Kullemölla 1 core showing that the apparent hiatus recorded by calcareous microfossils elsewhere is likely a result of post-depositional dissolution of calcareous tests and limestone, a process that did not affect the organic-walled plankton. This is further supported by the presence of hardgrounds and dissolution features. This updated, detailed biostratigraphical assessment based on dinoflagellates provides a framework for correlation with zonations based on other marine fossil groups, useful, for e.g., correlating aquifers in subsurface successions and, further, provides opportunities for linking marine and continental biotas. [ABSTRACT FROM AUTHOR]

A new soft-winged flower beetle, Burmalachius acroantennatus gen. et sp. nov. belonging to the tribe Malachiini (Coleoptera: Malachiidae), discovered in mid-Cretaceous Burmese amber is described. The new genus differs from the congeners of the tribe Malachiini in possessing the following characteristics: anterior tibiae widened and slightly curved inwards and excavate near the apices, tarsomeres of anterior legs depressed, 1st to 3rd tarsomeres simple and almost of equal size, tarsal comb lacking, "clavate" antennae due to dilated three apical antennomeres, 1st and 2nd antennomeres enlarged and of identical size, head strongly elongate, sides of elytra with carinate margins and widened epipleurae. This is the first record of the family Malachiidae in Burmese amber. Illustrations of the newly described species are provided. Keys for the identification of Melyrid lineage families, subfamilies of Malachiidae, tribes of the subfamily Malachiinae and genera of the tribe Malachiini are also given. [ABSTRACT FROM AUTHOR]

The Sierra Madre Group of Chiapas has informalities in its stratigraphic nomenclature that have been transmitted through geological literature. This work describes the characteristics of three lithostratigraphic successions that make the tripartite division of the Sierra Madre Group understandable. A particular lithology, which here is defined as the El Chango succession, separates the Cantelhá and Cintalapa successions to integrate this group. Additionally, the El Chango succession makes it possible to do an appropriate mapping and its correlation allows interpreting the regional distribution of sedimentary facies that these successions. Epifluorescence of rocks from the El Chango succession (Cenomanian) exhibits organic compounds. Pyrolysis data indicate ~0.22% of total organic carbon in carbonate rock, its equivalent reflectance is 0.7 and 1.0, which places the rock in the generation window of metagenic oil and gas, S2 values less than 0.2 mg HC/g make the low hydrocarbon expulsion potential questionable, so additional analyzes are required. The porosity impregnated with asphalt in rocks of the Sierra Madre Group suggests the existence of reservoir rock, regionally covered by pelitic rocks as a seal, and the changes in facies and deformation indicate the existence of potential traps. The data from this work proposes to explore a hypothetical oil play in this region. [ABSTRACT FROM AUTHOR]

The first biological inclusion in Cretaceous (Cenomanian) amber from Texas (USA) is here documented. Most of the Cretaceous ambers with biological inclusions are from Europe (Spain, France) and Myanmar (Asia). Although the coleopteran here reported is microscopic and incomplete, it preserves enough morphological details to be identified as a member of the Family Ptinidae Latreille, 1802. This antecedent is significative and reveals the potential of this Cretaceous amber to contain more diverse bioinclusions, since the paleoenvironment suggested by the sediments that contain the amber and the ecological affinity of recent representatives of the Ptinidae suggest a humid forest near an estuary, associated to deltaic plain deposits. Este hallazgo representa la inclusión biológica en ámbar más antigua en las Americas. [ABSTRACT FROM AUTHOR]

Dryopteridaceae are the basal family of Eupolypods I (Polypodiales) and include abundant extant species, but fossil occurrences are limited, particularly from a temporal perspective. Although DNA-based molecular studies indicate that the origin of Dryopteridaceae dates to the Early Cretaceous, no unambiguous fossil of the family has been reported from the Cretaceous period. Here, we report a new fern taxa based on well-preserved fertile specimen frond from mid-Cretaceous Kachin amber. Based on sporangia with interrupted, vertical annulae; monoletee spores; and the absence of indusia, the fertile fern fossil has been assigned to a new genus of Dryopteridaceae (Polypodiales). This represents the first fossil record of Dryopteridaceae from the Mesozoic and its mid-Cretaceous age is largely consistent with molecular-based estimates of divergence time. The fossil extends our understanding of polypod fern diversity in Mesozoic forests. [ABSTRACT FROM AUTHOR]

Three species belonging to the fern genus Ochotopteris E. Lebedev, including the new species O. lebedevii Herman et Domogatskaya, are revised, described and illustrated in this paper. The fossils come from Albian, Cenomanian, Turonian and Coniacian beds exposed at seven sites in North-Eastern Asia and Northern Alaska. These sites are located in the Cretaceous Arctic, with their palaeolatitudes ranging from 60° N to 80° N. The high endemism characteristic of the mid-Cretaceous Arctic flora is most probably due to adaptations in the globally distinctive Arctic conditions: the unique combination of temperatures, precipitation and the highly seasonal polar light regime. Being an endemic plant of the mid-Cretaceous Arctic, Ochotopteris ferns were adapted to a regional wet temperate to a wet warm temperate palaeoclimate accompanied by marked sunlight seasonality with a prolonged—up to several weeks—winter darkness and continuous summer daylight, also lasting for several weeks. The majority of the mid-Cretaceous Arctic plants were deciduous. Their predominant deciduousness was most probably due to the polar light seasonality: at the end of the growing season, some plants dropped their leaves or leafy shoots, whereas others—including Ochotopteris ferns—died back to rhizome systems. [ABSTRACT FROM AUTHOR]

The present study has focused on the lithology and mineralogy of the Bangestan reservoir shale unit, 5 meters thick at the 45 m below the upper boundary of Sarvak formation, located in the Lali oil field, to clear the existing lithostratigraphic ambiguities which refer it as a tongue of the Surgah Formation. After examining the petrophysical logs to determine the exact location of these deposits and core descriptions, the petrography of the collected samples was performed by light, reflective, cathodoluminescence and electron microscopy, and XRD analyses to recognize the mineralogy of the total sample as well as clay minerals. Core studying indicates that the unit is pyrite bearing gray shales. Moreover, based on petrography, the studied samples are argillaceous and fossil-free mudstone. The results of semiquantitative X-ray diffraction (XRD) analysis show that the mineralogy of these deposits is mainly clay minerals, calcite, quartz, and pyrite. The samples' average abundance of clay minerals is 56%, and the most frequent ones are the mixed-layered clays (illite/smectite), illite, and kaolinite, respectively. The electron microscopy (SEM) images often exhibit clay minerals of detrital origin. Due to the lack of fossils, the age of this unit was determined based on its stratigraphic position, which is surrounded by the Sarvak Formation deposits of the Cenomanian age and is distinguished from the Sorgah Formation (Turonian- Santonian age). Due to the absence of deep-marine organisms in this unit and the identification of lagoon and shoal carbonate microfacies in its surrounding layers, a calm and reducing lagoon environment is attributed to these sediments, which is against the deep marine environment of the Surgah Formation. Most common diagenetic processes (cementation, replacement, chemical compaction, and fracturing) indicate that the shale unit has been influenced mainly by shallow to deep burial diagenesis. There fore this shale unit with a shallow sedimentary environment, low thickness, relatively high content of detrital clay minerals, and their location at 45 meters below the boundary of Sarvak and Ilam formations belong to the Sarvak and is not correlatable with deep-marine shales of Surgah Formation. [ABSTRACT FROM AUTHOR]

The fossil record of stag beetles (Lucanidae), especially in Mesozoic amber, is sparse. Four additional fossil lucanids preserved in mid-Cretaceous Kachin amber from northern Myanmar are here reported. All of these species are included in the primitive subfamily Aesalinae, and have been identified as: Protonicagus mandibularis sp. nov. (tribe Nicagini); Cretognathus minutissimus gen. et sp. nov. (tribe Ceratognathini); Ceratognathini gen. et sp. indet. 1 (provisional assignment); and Ceratognathini gen. et sp. indet. 2 (provisional assignment). Except for Protonicagus mandibularis sp. nov., the stag beetles appear to be connected to the continent of Gondwana, as with the Kachin amber paleofauna. More interestingly, these species have significantly smaller bodies than the extant species, with three of them measuring less than 3 mm, which makes them the smallest known species of Lucanidae. This finding is congruent with a trend toward miniaturization in several unrelated lineages of Kachin amber beetles, and it shows hidden paleodiversity of stag beetles during the Cretaceous. [ABSTRACT FROM AUTHOR]

A key but challenging task for biostratigraphers is to provide a biozonal/bioevent framework for geological correlation. Species of Larger Benthic Foraminifera (LBF) are important biostratigraphic markers in depositional environments where classical biostratigraphic fossils such as planktonic micro- and macrofossils are rare or absent - e.g., tropical-subtropical shallow water platforms. However, a lack of taxonomic rigour in identifying some LBF species, together with a lack of good age-calibration of their occurrences, has given rise to artificially extended biostratigraphic and paleogeographic ranges for many taxa, diluting their usefulness. In this study, the occurrences of Cenomanian LBF belonging to a "planispiral morphogroup", both agglutinated and calcareous, have been critically evaluated to determine (i) identity; (ii) stratigraphic range; and (iii) palaeogeographic distribution. Since the last major review of the group in 1985, a voluminous literature has appeared reporting occurrences and adding new taxa. An extensive review of some 600+ published items on Cenomanian planispiral LBF - mostly published after 1985 - and a critical review of the confidence in species identification and age-calibrations therein, has led us to identify 39 taxa (three in "open" status) which appear to have distinct identity. The vast majority of these records are from Neotethys although some also occur in (or are endemic to) the Caribbean/West Atlantic and the Eastern Pacific. The quality of the published taxonomic data is variable and many published records based on identity can be discounted or termed "unconfirmed". Likewise, many records (confirmed or otherwise) are poorly age-calibrated due to lack of corroborating biostratigraphy or chemostratigraphy, or by using circular reasoning. We summarise and illustrate the main defining characteristics of each taxon and their possible confusion species, including new taxa described since the mid-1980s. We publish new, more confident, age-ranges for these taxa - confirmed by identity and/or age-calibration - and identify where published range data may be unreliable. Paleogeographic distribution maps for each taxon are also provided. Particular stratigraphic issues around the Cenomanian-Turonian boundary are observed due to the difficulty of identifying that boundary, or its preservation, in shallow marine carbonate settings. Although most Cenomanian planispiral LBF are somewhat long-ranging, an increase in diversity throughout the middle - late Cenomanian has shown potential for biostratigraphic resolution to at least substage level using this group. Integration of the planispiral taxa with other LBF morphogroups, after similar treatment, will yield even higher biostratigraphic resolution of Cenomanian LBF and provide a sound basis for biozonation (both local and global), correlation, and age calibration. [ABSTRACT FROM AUTHOR]

The benthic foraminifera Murgeina apula (Luperto Sinni), originally described as Nummofallotia apula from the Upper Cretaceous of southern Italy, represents a common taxon in the middle-upper Cenomanian Sarvak Formation of southwestern Iran as well as the Campanian-early Maastrichtian of Croatia. The specific identity of the Iranian and Italian as well as Croatian specimens is confirmed by equivalent biometric data and identical test structure. The agglutinated wall (inner part) of M. apula excludes its assignment to the porcelaneous Nummofallotia Barrier & Neumann. Nummofallotia is currently placed in the family Meandropsinidae Henson, while for Murgeina with its bilamellar wall inclusion in the Ventrolaminidae Weynschenk is favoured. Nummofallotia cenomana Luperto Sinnni, described from the Cenomanian of southern Italy and lacking any hard facts for species discrimination (e.g., dimensions, inner structure) is herein considered tentatively a junior synonym of Murgeina apula requiring reexamination of the type-material. M. apula represents another survivor of the Cenomanian-Turonian boundary extinction event and, with a long stratigraphic range from the middle Cenomanian to the (early) Maastrichtian, is similar to another Methusalem taxon such as Moncharmontia apenninica (De Castro) with a comparable range. [ABSTRACT FROM AUTHOR]

The carbonate succession of the Cenomanian-Turonian Sarvak Formation SW Iran, Zagros Zone contains a diverse assemblage of (larger) benthic foraminifera, such as alveolinids, orbitolinids and others. Two new taxa are described herein as Pseudocyclammina sarvakensis sp. nov. and Pseudotextulariella brevicamerata sp. nov. They are generally not frequently observed (likely biased through a stratigraphic or facies control) as other most common taxa found in the Sarvak Fm. They are herein reported from the Tang-e Darbast (type-locality of both species) and Shahneshin surface sections, and also from the Arman well-1 subsurface section, Fars area and Abadan Plain, respectively in the parts referred to the middle Cenomanian. The Tang-e Darbast section also represents the type-locality of Iraqia ultima Yazdi-Moghadam & Schlagintweit and Simplorabanitina simplex Consorti, Schlagintweit & Yazdi-Moghadam. Pseudocyclammina sarvakensis and Pseudotextulariella brevicamerata are further elements of the socalled 'Nezzazata-alveolinid' assemblage zone. [ABSTRACT FROM AUTHOR]

Amber and plant remains were discovered in the lower Cenomanian lignitic clay from La Gripperie-Saint-Symphorien (Charente-Maritime, western France). The amber mainly consists of scarce and infracentimetric pieces showing a wide range of sizes and colours. The shape of the amber grains greatly varies, including more or less cylindrical fragments of flows and spherical drops. Plants consist of foliar remains corresponding to isolated pinnae and pinnules of ferns (Matonia sp., Weichselia reticulata (Stokes & Webb, 1824) Fontaine emend. Alvin, 1971), leafy axes of conifers (Geinitzia reichenbachii (Geinitz, 1842) Hollick & Jeffrey, 1909, Pagiophyllum sp.) and leaves of angiosperms (including cf. Eucalyptolaurus depreii Coiffard, B.Gomez, Thiébaut & J.Kvaček and three morphotypes of undeterminable leaves). They are preserved as isolated cuticles, charcoalified compressions without cuticle, and external casts. Angiosperms are clearly the most abundant and diverse remains of the plant assemblage. This latter contrasts with most of Albian-Cenomanian coastal floras from the Aquitaine Basin, which are dominated by gymnosperms characterised by xeromorphic adaptations and tolerating halophytic conditions. Similar to the coeval sites of Puy-Puy (Charente-Maritime) and Jaunay-Clan (Vienne), the plant-rich clay from La Gripperie-Saint-Symphorien was probably deposited in innermost coastal environments heavily influenced by inland/continental freshwater. [ABSTRACT FROM AUTHOR]

Beginning from the mid-Cretaceous and in the Late Cretaceous, the landscape features of the North Pacific make it possible to divide this region into a number of territories called subregions. The earliest Cenophytic (with a significant number and diversity of angiosperms) late Albian–early Turonian Grebenka flora and its analogs are known only in three subregions of the North Pacific: Anadyr–Koryak, Northern Alaska, and Yukon–Koyukuk. In the middle of the Cretaceous, these subregions represented coastal plains and lowlands periodically flooded by the sea. Cenophytic floras populated the area of terrestrial volcanism of the Okhotsk–Chukotka subregion and the Asian continental interiors of the Verkhoyansk–Chukotka subregion later, in the Turonian–Coniacian. However, Mesophytic vegetation with the predominance of Early Cretaceous ferns and gymnosperms continued to exist there at least until the Coniacian. Consequently, the invasion of evolutionarily new Cenophytic vegetation into the continental interiors of Northeast Asia was gradual and extended over time. This should be taken into account when studying the Cretaceous nonmarine phytostratigraphy of the North Pacific region. [ABSTRACT FROM AUTHOR]

Mid-Cretaceous amber from Northern Myanmar, also known as "burmite", contains the most productive and species-rich amber sites in the world. Up to now, 17 families of cockroaches in Burmese amber have been documented. However, only four extinct species of family Mesoblattinidae have been reported in Burmese amber so far: Spinaeblattina myanmarensis Hinkelman, 2019; Mesoblatta maxi Hinkelman, 2020; Cuniculoblatta brevialata Hinkelman, 2021; and Mongolblatta sendii Hinkelman, 2021. The new species Sivis tykadlo sp. n. described here on the basis of both sexes give us an opportunity to better understand the morphological and ecological characters of Cretaceous cockroaches and the entire fauna. An ecosystem with a humid climate in the mid-Cretaceous apparently enriched the diversity of cockroach species. This fossiliferous amber has produced more than 4,000 cockroach specimens of many different forms and lifestyles. [ABSTRACT FROM AUTHOR]

We present the first detailed braincase anatomical description and neuroanatomical study of Portugalosuchus azenhae, from the Cenomanian (Late Cretaceous) of Portugal. This eusuchian crocodylomorph was originally described as a putative Crocodylia and one of the oldest representatives of this clade; however, its phylogenetic position remains controversial. Based on new data obtained from high resolution Computed Tomography images (by micro‐CT scan), this study aims to improve the original description of this taxon and also update the scarce neuroanatomical knowledge of Eusuchia and Crocodylia from this time interval, a key period to understand the origin and evolution of these clades. The resulting three‐dimensional models from the CT data allowed a detailed description of its well‐preserved neurocranium and internal cavities. Therefore, it was possible to reconstruct the cavities of the olfactory region, nasopharyngeal ducts, brain, nerves, carotid arteries, blood vessels, paratympanic sinus system and inner ear, which allowed to estimate some neurosensorial capabilities. By comparison with other crocodylomorphs, these analyses showed that Portugalosuchus, back in the Cenomanian, already displayed an olfactive acuity, sight, hearing and cognitive skills within the range of that observed in other basal eusuchians and crocodylians, including extant species. In addition, and in order to test its disputed phylogenetic position, these new anatomical data, which helped to correct and complete some of the original observations, were included in one of the most recent morphology‐based phylogenies. The position of Portugalosuchus differs slightly from the original publication since it is now located as a "thoracosaurid" within Gavialoidea, but still as a crocodylian. Despite all this, to better contrast these results, additional phylogenetic analyses including this new morphological character coding together with DNA data should be performed. [ABSTRACT FROM AUTHOR]

Shale-rich reservoirs present a long-standing challenge for reservoir geologists because the clay minerals often induce a large-scale heterogeneity in the reservoir pore system. This work aims to understand the impact of clay distribution and mineralogy which would enhance the predictability of the best reservoir facies. We integrate seismic, well-log datasets to investigate the petrophysical characteristics of the clay-rich Cenomanian Clastics in the GPY oil field, north Western Desert of Egypt. These Clastics comprise the sandstone intervals which are the most prolific hydrocarbon reservoirs. Seismic data were used to interpret the main structural patterns as well as the different seismic facies. The well log data were utilized to interpret the lithologic variations and the type of clays in the reservoir as well as the different petrophysical parameters. Based on variations in their lithological and petrophysical characteristics, the Bahariya sandstones were sub-divided into three different rock units: Bahariya-3 (B-3), Bahariya-2 (B-2), and Bahariya-1 (B-1), separated by thick laminated clay intervals. AR/G Member is dominated by clays with relatively lower reservoir quality. Spectral gamma ray log values reveal that smectite is the dominant clay mineral in all the studied intervals. Laminated clays are dominant in B-1 and B-2 units, whereas, B-3 unit and Abu Roash G Member are enriched in structural clays. The quartzose sand content decreases from B-3 to AR/G and clay content increases from B-3 to AR/G. Therefore, the best reservoir facies and fluid flow conduits with best pore system characteristics are hosted in B-3 and the smectite clay streaks act as a good seal for hydrocarbons in the quartzose sandstone pay zone. [ABSTRACT FROM AUTHOR]

A new genus and species of froghopper, Araeoanasillus leptosomus gen. et sp. nov. (Hemiptera: Cercopoidea, Sinoalidae?), is described from mid-Cretaceous Burmese amber. The new genus possesses the following diagnostic characteristics: slender, medium size body (length, 7.0 mm) with head longer than wide, round eyes; antennae slender with eight antennomeres; pedicel very short, shorter than scape; pronotum with a length/width ratio of 2.4; metatibia with three spines, including one short spine near base and two adjacent, long, thick spines near apex; a single series of 16 thick apical teeth (comb) at metatibial apex; tegmen narrow with a length/width ratio of 3.2; tegmen with coastal area and stigmal cell punctate; CuP meeting base of CuA2; and MP branching at middle of wing. In hind wing, Cu vein forked once. A series of plant trichomes adjacent and attached to the specimen suggests that the froghopper's host plant was a fern. [ABSTRACT FROM AUTHOR]

In the northern Aurès Range near Batna, Algeria, the Cenomanian Smail Marls Formation consists of fossiliferous deposits rich in diverse benthic macrofauna, mostly dominated by bivalves, among them the carditid Maghrebella forgemoli (Coquand, 1862). Almost exclusively Cenomanian, the abundance zone of Maghrebella forgemoli is in the higher levels of Lower Cenomanian, extending from the Sharpeiceras schlueteri zone to the Mantelliceras dixoni zone and corresponds to a limited circalittoral interval with relatively low energy, soft substrata, and relatively cold temperatures. The distribution of Maghrebella forgemoli in Mountains of Batna evidences bathymetric variation controlled by the tectonic activity affecting the ante-Triassic and the Upper Cretaceous substrata and generating a system of tilted blocks, at the beginning of the uppermost Albian-Cenomanian and Turonian, in the eastern Atlasic domain that extends to central Tunisia. [ABSTRACT FROM AUTHOR]

Carentonosaurus soaresi was recently described in the uppermost middle Cenomanian (Upper Cretaceous) of Casais dos Carecos (Coimbra, western Portugal) based on a diverse set of new material (cervical and dorsal vertebrae) of the Pythonomorpha lizard. The main morphological characteristics observed in the vertebrae used for the diagnosis of this species are the presence of distinct lateral and subcentral foramina, highly laterally projected paradiapophyses beyond the prezygapophyses, a low subrectangular neural spine ornamented with longitudinal grooves, and dorsal vertebrae displaying a sagittal furrow along the ventral surface. Additional diagnostic details observed both in new material and the previously studied vertebrae are described herein, such as the presence of keels in the zygantrum and zygosphene. These and other important morphological characteristics present in the species soaresi are absent in the genotype Carentonosaurus mineaui and in other known Squamata, allowing for the definition of the new genus Segurasaurus.