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The taxonomic affiliation of the species Haplophragmoides (?) emeljanzevi Schleifer, 1966 and Recurvoides paucus Dubrovskaja, 1962 is revised. It is shown that both species should be assigned to the subfamily Recurvoidinae Alekseychik-Mitskevich, 1973, and classified in a new genus Bassoviellum gen. nov. Representatives of the new genus from the Volgian, Ryazanian and Valanginian Stages of the Arctic (Upper Jurassic and Lower Cretaceous) are described. The identification criteria of the species have been clarified. [ABSTRACT FROM AUTHOR]

Quantitative palynofloral analysis of late Berriasian to early Hauterivian aged sediments from the Vocontian Basin of southeast France has involved fifty-four outcrop samples from Vergol (Montbrun-les-Bains) and twenty-seven from La Charce (Serre de l'Âne). All samples were marls except for two from the early Valanginian Barrande layers, thin black layers rich in organic carbon. Sampling was focused particularly on the Berriasian/Valanginian, early/late Valanginian and Valanginian/Hauterivian boundaries with two of these particularly important as La Charce is the GSSP for base Hauterivian and Vergol is a GSSP candidate for base Valanginian. Although little has been previously published on the palynology of the Vocontian Basin, this study has benefitted from many previous multi-disciplinary studies in the area; the numerous palynofloral events recorded are tied closely to the standard ammonite zonation. Analyses were mainly focused on the dinocysts, but miospores have also been considered in terms of their palaeoenvironmental response, allowing broad assessment of relative sea level changes. Some linkage between peaks in coastal/lowland ratios, the d13C curve through the Weissert carbon isotope excursion (CIE) and the Muderongia group (possible reduced salinity) have been shown. A new dinocyst zonation scheme is proposed, involving twelve zones, eight of which cover the Valanginian; previous schemes are briefly discussed. Two genera, twenty-three species and five subspecies of stratigraphically-significant dinoflagellate cysts are described as new, two genera have been emended and thirteen new combinations have been proposed. The diagnosis of one acritarch genus has been emended and two new combinations effected. [ABSTRACT FROM AUTHOR]

Extremely rare skeletal remains of brittle stars, originating from Lower Cretaceous deposits in the Štramberk area are described and a preliminary discussion of depositional environments represented by these rocks is added. Several assemblages of dissociated ossicles from the Kopřivnice Formation (upper Valanginian; mostly from the Kotouč and Lower Blücher quarries) comprise only vertebrae. In contrast, an assemblage from the ?Hradiště Formation (Hauterivian and Barremian; Municipal quarry) has yielded taxonomically important lateral arm plates, which have enabled the present study of ophiuroid diversity. A total of five species have been found, including a single new taxon, Ophiotitanos moravica sp. nov. The remaining taxa are left in open nomenclature. Similar to what has been documented from the Cenomanian and Turonian of the Bohemian Cretaceous Basin, representatives of the genus Ophiotitanos predominate in the present assemblages. The presence of Ophiotitanos, euryalids, ophiomusaids and ophiacanthins is reminiscent of some ophiuroid faunas from the Upper Cretaceous of Europe. The assemblage from the Municipal quarry differs markedly from ophiuroid faunas of the Aptian of Cuchía (Spain) and Wizard Way (Texas), but is closely similar to the one from the Barremian of Serre de Bleyton (France). Problems surrounding echinoderm occurrences in the Kopřivnice and ?Hradiště Formations are discussed. [ABSTRACT FROM AUTHOR]

The discovery of the new ammonite Altudostephanus longicostis gen. et sp. nov. around the lower/upper Valanginian boundary (Lower Cretaceous) with a true longitudinal ribs pattern oriented in the direction of coiling is reported here for the first time for the Cretaceous. This character rises questions as this type of ornamentation is mainly represented in the Paleozoic or old Mesozoic taxa. Its study shows that it is not a 'shell accident' and that it belongs to a particular lineage of Olcostephaninae, in a restricted geographical area and in a progenetic evolutionary context derived from Olcostephanus, which justifies the introduction of the new monophyletic genus Altudostephanus gen. nov. The discovery of a specimen of Passendorferia sp. (Oxfordian, Upper Jurassic) with the same pattern allows us to consider that this capacity could have a genetic cause. It seems that the fixation of this character, otherwise strongly recessive, in A. longicostis gen. et sp. nov. could take place thanks to a founder effect and the drastic numerical reduction in the population. The geological reference section PIG5 (Moriez area, South-Eastern France) is described, and the problem of the conservation of 'pyritic' s.l. ammonites is addressed with a proposed methodology allowing their long-term conservation. [ABSTRACT FROM AUTHOR]

Early Cretaceous deposits (Berriasian–Albian) crop out over large areas in the Vocontian Basin (VB, southeast of France). The important exposures have provided rich marine fossil faunas, including many specimens of ammonites and belemnites over the last 200 years. From the early 19th century onward, the definition of Lower Cretaceous belemnite species from the VB was essentially based on descriptive, qualitative approaches. This resulted in a variety of morphologically very closely related species, sometimes difficult to differentiate between each other. Biometric data and their statistical analysis offer a mathematical and objective framework to clearly delineate and define morphological species, especially when consecutive belemnite assemblages are continuously available from different stratigraphic levels. The present study is based on the analysis of 1762 specimens of Castellanibelus collected by ammonite zones and subzones across the entire Valanginian interval of the VB. Biometric data of this genus have been statistically analyzed and used to define four species, including one new to science: Castellanibelus orbignyanus, Castellanibelus vaubellensis, Castellanibelus suborbignyanus, and Castellanibelus toucasi sp. nov.

Abstract From the Vitznau Marl (lower Valanginian) at the locality Wart in northeastern Switzerland (Alpstein area), 18 species from 17 genera and 13 families are described, including the genera Actinaraea, Actinastrea, Adelocoenia, Aplosmilia, Axosmilia, Complexastrea, Cyathophora, Dermosmilia, Fungiastraea, Heterocoenia, Latiastrea, Montlivaltia, Placophyllia, Pleurophyllia, Stylophyllopsis, Thamnoseris, and specimens showing affinities to solitary stylophyllids. The corals from the Vitznau Marl were derived from a limestone–marl alternation that is fossiliferous and clay-rich at the base (Vitznau Marl), containing crinoids, bryozoans, and sparse reworked corals and sponges. The coral fauna is distinctly dominated by forms belonging to the category of lowest to no polyp integration (50%), followed by species of the cerioid-plocoid group (33%) and forms having the highest polyp integration (thamnasterioid; 17%). With regard to polypar size, the Wart fauna is dominated by corals having large-size (> 9 mm) polyps (= 39%), followed by corals having medium- (> 2.5‒9 mm; 33%) and small-size polyps (up to 2.5 mm; 28%). Based on morphological features, the fauna from the Vitznau Marl closely corresponds to coral assemblages that are subjected to near-chronic, moderate sediment-turbidity stress that is punctuated by high-stress events, and that are largely or entirely heterotrophic. No coral fabric was observed that would suggest a biohermal development. But in a very small number of places, structures are present which might be fragments of crusts of microbialites, pointing to the hypothesis that at least a few of the corals might have been a part of some kind of bioconstruction. At the species-level, the fauna of the Vitznau Marl shows either no or very little affinities to other Valanginian assemblages such as to the fauna of Hungary (4.3%), followed by the associations of Ukraine, Switzerland (non-Vitznau), Spain (SpII), and Bulgaria. At the genus-level, the Wart fauna shows low correspondence to the fauna of Spain (SpII) (14.5%), followed by the assemblages of Hungary, Bulgaria, and Ukraine. In addition to the Vitznau Marl corals, an account of all Valanginian coral faunas published before early 2021 is given, including their paleogeographic distribution, as well as their taxonomic and morphological characterization. For this preliminary study, a total of 206 coral species belonging to 97 genera found in the coral assemblages of the Valanginian were included. At both the genus- and the species-levels, colonial taxa are most abundant (colonial genera: 89%; colonial species 90%). The vast majority of the Valanginian genera already occurred in older strata. Only 11 genera (out of 97 = 11%) are newly recorded. The Valanginian faunas having the largest number of solitary taxa lived in both (sub-) paratropical to warm-temperate areas, and in arid regions. The coral faunas of the Valanginian are distinctly dominated by corals of well-established microstructural groups. Only 13% of the species from 24% of the genera belong to “modern” groups. Compared to the situation in the Berriasian which showed that 9% of the species and 17% of the genera belonged to modern microstructural groups, the occurrence of “modern” groups significantly increased during the Valanginian.

We report the first cephalopod statoliths from the Early Cretaceous. These unique microfossils fill the gap in the fossil record between Jurassic and Cenozoic forms, and are more similar to the former. We compare the morphology of the Mesozoic forms with the statoliths from Recent and Cenozoic decabrachians. This comparison shows the closest resemblance to the Recent Idiosepiidae. We suggest that Mesozoic cephalopod statoliths belong to the basal decabrachians and they are related to the idiosepiids. The belemnitid identity of these forms can be neither confirmed nor rejected though some positive correlation in the investigated materials between findings of belemnitid rostra and statoliths do occur. These finds support also some previous suggestions that decabrachians and vampyropods diverged earlier than in the Early Jurassic. We discuss the absence of the wing in the Mesozoic statoliths and suggest that the robustly developed spur could play a similar role to the wing in Cenozoic and Recent decabrachian statoliths. We suggest that the statolith morphology might be a useful tool to interpret cephalopod evolution. We also note an evident shift in the abundance ratio of statoliths vs fish otoliths, the former being dominant in the Jurassic while declining in abundance in the Cretaceous. This supports a Cretaceous turnover in several groups of marine organisms. [ABSTRACT FROM AUTHOR]

The Jurassic to Cretaceous strata exposed in the Rollrock Section, Sverdrup Basin, Arctic Canada, represent one of the northernmost continuous outcrops spanning this poorly understood transition. The Oxfordian–Valanginian mudstones of the Rollrock Section were deposited in a shallow marine environment and, as such, provide the ideal lithology to investigate the response of high latitude dinoflagellate cyst populations to the frequent environmental perturbations of this time. Using a multivariate statistical approach, distinct palaeoecologically significant groups are identified and directly linked to time and palaeoenvironments, allowing for the reconstruction of underlying long term palaeoenvironmental trends. These palaeoenvironmental trends are identified to be driven by sequence stratigraphic cycles. For the first time, fourth order sequences are recorded from this pivotal period in the Sverdrup Basin and reveal an additional level of short term climatic events that complicate the identification of long term trends. The relationship existing between marine phytoplankton and climate is utilised to decipher the interplay of long-term and short-term climate fluctuations, distinguishing them from evolutionary trends. Two groups of dinoflagellate cysts, identified by process morphology, are recorded to act as environmental proxies. High percentages of proximochorate dinoflagellate cysts, such as Trichodinium erinaceoides , indicate more proximal, high energy, nutrient rich conditions and are dominant in fourth order transgressive systems tracts. High percentages of chorate dinoflagellate cysts, such as Oligosphaeridium complex , signify distal, low energy, nutrient depleted conditions and are dominant in fourth order highstand systems tracts. [ABSTRACT FROM AUTHOR]

The cross-border Geopark Karawanken/ Karavanke was established in 2011 to reflect the diverse geological composition and varied and rich natural and cultural heritage of the area. The wealth of geological heritage is reflected in numerous, already existing geosites, exceptional and unique on a global level, as well as in newly determined mineral and fossil sites. An example of the latter is the fossil site with rare Valanginian-Hauterivian heteromorphic ammonites, located in the SE part of the Karawanken/ Karavanke UNESCO Global Geopark, near Leše village above Prevalje. It is the first and newly discovered locality of heteromorphic ammonites Himantoceras trinodosum Thieuloy, 1964 and Crioceratites cf. nolani Kilian, 1910 in Slovenia. We explore the importance and potential of good cooperation between the local community, paleontologists and other geoscientists, geoheritage (paleontological heritage) conservation and UNESCO Global Geoparks.

Here we describe a new ornithopod species, Emiliasaura alessandrii gen. et sp. nov. from Valanginian rocks (Early Cretaceous) of northwestern Patagonia. This new taxon exhibits affinities with the Rhabdodontomorpha and is primarily represented by two specimens of mid-sized ornithopods collected from different sites and stratigraphical levels of the Mulichinco Formation. The holotype specimen MLL-Pv-001 includes the coracoid, the proximal end of a scapula, a humerus and a complete right hind limb, whereas the paratype specimen MLL-Pv-006 preserves vertebral elements, haemal arches, an incomplete pelvis, and nearly complete hind limbs. The new taxon has an anteroposteriorly elongate ilium with a sigmoidal dorsal border and broad brevis shelf, a femur shaft with an extensive, mid-shaft positioned fourth trochanter, and a second pedal digit with a short, robust, blunt ungual phalanx similar to those in Ankylopollexia ornithopods. The new ornithopod taxon formed part of a diverse dinosaur association from the Mulichinco Fm that includes dicraeosaurid sauropods and carcharodontosaurid theropods, and represents the first South American record of a rhabdodontomorph, and the oldest and most primitive representative of this clade. [Display omitted] • A new taxon of the dinosaur clade Ornithopoda, Emiliasaura alessandri , is described. • Emiliasaura is the first recognized South American rhabdodontomorph ornithopod taxon. • Emiliasaura represents the earliest Patagonian Cretaceous ornithischian dinosaur. [ABSTRACT FROM AUTHOR]

An ammonite biostratigraphic analysis was carried out for the La Peña del Águila section, Zacatecas State, northern Mexico, within Valanginian strata of the Taraises Formation. Bed-by-bed sampling yielded 208 ammonites identified in 13 taxa. The biostratigraphic analysis allowed us to identify two ammonite zones: Neocomites neocomiensiformis and Karakaschiceras inostranzewi ; and one subzone: Neocomites platycostatus. These biostratigraphic units range within the lower Valanginian. The identified fauna in the La Peña del Águila section has been previously reported in the Mediterranean region. The faunal similarity allows us to employ the Standard Mediterranean Ammonite Scale for the analysis of the current section. This affinity between the Mexican and Mediterranean ammonite faunas could be explained by the proximity and communication between these two areas through the Hispanic corridor during the Valanginian. • 208 ammonites of Zacatecas are studied from a biostratigraphic point of view. • The ammonite assemblages range within the lower Valanginian. • Ammonite assemblages of Mexico and Spain are very similar. [ABSTRACT FROM AUTHOR]

Yamama Formation is the most important and widespread Lower Cretaceous Formation in Iraq. Yamama Formation in the Luhais well-12 and Rifaee well-1 are composed of dolomitized in some places and foraminifera and algae bearing limestone, 19 genera and species of foraminifera, 10 genera and species of algae. Two biozones were distinguished Pseudochrysalidina arabica Range zone and Pseudocyclammina lituus Range zone. The age of the formation was determined as Berriasian – Valanginian according to these biozones of Foraminifera. In this study, bryozoa, Gastropoda and Pelecypoda are recorded but less than Foraminifera. [ABSTRACT FROM AUTHOR]

This paper describes a petrified trunk collected from a conglomerate bed of the Springhill Formation (Berriasian–Valanginian) in the Estancia El Álamo locality, Santa Cruz Province, Argentina. The fossil trunk is classified within theubiquitous genus Agathoxylon and the wood anatomy shows a close affinity to that of Araucariaceae. This Patagonianwood has a distinct combination of anatomical characteristics unique among all known species from the Jurassic andCretaceous of Western Gondwana allowing to diagnose a new fossil taxon Agathoxylon mendezii sp. nov. Sedimentologicaland megafloristic proxies of the Springhill Formation suggest that Agathoxylon mendezii sp. nov. grew under awarm and wet climate, which indicates a subtropical to temperate palaeoenvironment. However, the large number of frostrings in the earlywood of this araucarian tree suggests that the palaeoenvironment at Estancia El Álamo was subjected torecurrent disturbances, most likely caused by regional continuous volcanic activity originating from volcanoes locatedfar away to the west. This activity would have produced periodic stratospheric veils that promoted rapid decreases insurface air temperature; the wood response to such stressful conditions would have been the formation of numerous (atleast five) frost rings. Although recurrent eruptions in Patagonia during the Early Cretaceous are well recorded, this studyis the first to register eruptions recorded in a coniferous wood.

The association between Large Igneous Provinces (LIPs) and mass extinctions and anoxic events is attributed to the radical climatic changes in Earth. Even though the Early Cretaceous Paraná–Etendeka Igneous Province has a comparable erupted volume (>1 Mkm3) to other LIPs (e.g., Deccan, Emeishan and Siberian Traps), it remains controversial why this LIP did not contribute to a mass extinction and whether it is associated with the Weissert Event. This work presents new 40Ar/39Ar dating over a 425‐m vertical stratigraphic profile (out of 1,000 m) that spans three formations of the PE‐LIP in southern Brazil (low‐Ti Vale do Sol, high‐Ti Urubici, and high‐Ti Palmas). Our data demonstrate that this mafic lava pile was emplaced in c. 2.0 m.y., from c. 135.5 Ma to c. 133.5 Ma, and endorse the hypothesis that the basaltic and andesitic flows of the Vale do Sol Formation (peak of mafic magmatism) contributed to the Weissert Event. [ABSTRACT FROM AUTHOR]

From the Vitznau Marl (lower Valanginian) at the locality Wart in northeastern Switzerland (Alpstein area), 18 species from 17 genera and 13 families are described, including the genera Actinaraea, Actinastrea, Adelocoenia, Aplosmilia, Axosmilia, Complexastrea, Cyathophora, Dermosmilia, Fungiastraea, Heterocoenia, Latiastrea, Montlivaltia, Placophyllia, Pleurophyllia, Stylophyllopsis, Thamnoseris, and specimens showing affinities to solitary stylophyllids. The corals from the Vitznau Marl were derived from a limestone–marl alternation that is fossiliferous and clay-rich at the base (Vitznau Marl), containing crinoids, bryozoans, and sparse reworked corals and sponges. The coral fauna is distinctly dominated by forms belonging to the category of lowest to no polyp integration (50%), followed by species of the cerioid-plocoid group (33%) and forms having the highest polyp integration (thamnasterioid; 17%). With regard to polypar size, the Wart fauna is dominated by corals having large-size (> 9 mm) polyps (= 39%), followed by corals having medium- (> 2.5‒9 mm; 33%) and small-size polyps (up to 2.5 mm; 28%). Based on morphological features, the fauna from the Vitznau Marl closely corresponds to coral assemblages that are subjected to near-chronic, moderate sediment-turbidity stress that is punctuated by high-stress events, and that are largely or entirely heterotrophic. No coral fabric was observed that would suggest a biohermal development. But in a very small number of places, structures are present which might be fragments of crusts of microbialites, pointing to the hypothesis that at least a few of the corals might have been a part of some kind of bioconstruction. At the species-level, the fauna of the Vitznau Marl shows either no or very little affinities to other Valanginian assemblages such as to the fauna of Hungary (4.3%), followed by the associations of Ukraine, Switzerland (non-Vitznau), Spain (SpII), and Bulgaria. At the genus-level, the Wart fauna shows low correspondence to the fauna of Spain (SpII) (14.5%), followed by the assemblages of Hungary, Bulgaria, and Ukraine. In addition to the Vitznau Marl corals, an account of all Valanginian coral faunas published before early 2021 is given, including their paleogeographic distribution, as well as their taxonomic and morphological characterization. For this preliminary study, a total of 206 coral species belonging to 97 genera found in the coral assemblages of the Valanginian were included. At both the genus- and the species-levels, colonial taxa are most abundant (colonial genera: 89%; colonial species 90%). The vast majority of the Valanginian genera already occurred in older strata. Only 11 genera (out of 97 = 11%) are newly recorded. The Valanginian faunas having the largest number of solitary taxa lived in both (sub-) paratropical to warm-temperate areas, and in arid regions. The coral faunas of the Valanginian are distinctly dominated by corals of well-established microstructural groups. Only 13% of the species from 24% of the genera belong to “modern” groups. Compared to the situation in the Berriasian which showed that 9% of the species and 17% of the genera belonged to modern microstructural groups, the occurrence of “modern” groups significantly increased during the Valanginian. [ABSTRACT FROM AUTHOR]

The first Early Cretaceous (Valanginian–Hauterivian) ammonite fauna from the lower part of the Kościeliska Marl Formation (Wściekły Żleb Member) of the Lower Sub-Tatric (Krížna) Nappe, in the Lejowa Valley of the Tatra Mountains are described. The fauna is precisely placed in the succession and consists of five species: Olcostephanus densicostatus, Spitidiscus cf. cankovi, Criosarasinella cf. subheterocostata, Crioceratites primitivus, and Crioceratites coniferus and additionally an aptychus Didayilamellaptychus seranonis. Remarkable are the valves of anomiid bivalves attached to body chamber of large size heteromorph ammonite C. primitivus. Moreover, a variety of stratigraphically important organic-walled dinoflagellate cysts are recovered from this locality. Dinoflagellates: Cymososphaeridium validum, Circulodinium vermiculatum, and representatives of Bourkidinium define the Upper Valanginian–Lower Hauterivian Sentusidinium sp. A Dinocyst Subzone of the Cymososphaeridium validum Zone. The character of deposits, the palynofacies, and associations of dinoflagellate cysts indicate a calm marine outer neritic environment.

The paper deals with newly discovered Valanginian-Hauterivian fauna of heteromorphic ammonites (Ancyloceratina) from locality south of the village of Leše above the Meža River valley (North Karavanke Mountains). Fossils were recovered from the pelagic limestone. Among the studied heteromorphic ammonites are Lower Cretacaoeus species Himantoceras trinodosum (Upper Valanginian) and Crioceratites cf. nolani (Hauterivian). Based on the accompanied ammonites (Ammonitina) from the outcrop, we biostratigraficaly confirm the presence of Lower Cretaceous ammonites fauna in the Northern Karavanke Mountains. This is also the first report on heteromorphic ammonites in Slovenia.

Based on the U–Th–Pb (SIMS) dating of zircons from magmatic bodies of trachytes and trachydolerites of the Upper Agyndzha complex located within the Rassokha island arc and Argatass oceanic terranes, we have reached a conclusion about the Valanginian age of its formation. In terms of the age and composition, the Valanginian volcanics of the Rassokha and Argatass terranes are close to those of the base of the Alazeya–Indigirka zone. The spatial position of Valanginian trachytes and trachydolerites does not allow us to consider them as suprasubduction formations of the Andean-type margin. This is due to the distance of these bodies from the main field of the Alazeya–Indigirka zone. It can be concluded that the formation of these bodies was associated with the extension within this zone. The tectonic position of the Valanginian magmatic bodies allows us to interpret them as complexes that amalgamated two geodynamically different terranes. [ABSTRACT FROM AUTHOR]

The first chondrichthyan teeth, dermal and oropharyngeal denticles from the Lower Cretaceous lacustrine Quiricó Formation (Sanfranciscana Basin), in southeastern Brazil are described. Eight microremains morphologies have been recovered from lower levels of this formation, dated as possibly Valanginian with basis on ostracods. The dermal denticles belongs to indeterminate Hybodontiformes; some teeth are ascribed to ?Lonchidiidae. The presence of Tribodus is suggested by some dermal denticles, but this assignment requires confirmation with more complete material. The new specimens indicate a much greater diversity of chondrichthyans in the Quiricó Formation than previously thought. The associated occurrence of hybodontiforms, the coelacanthiform Mawsonia and early neopterygians observed in the Sanfranciscana Basin is not uncommon for the Cretaceous sedimentary strata of Brazil and Africa. However, the use of the Quiricó Formation shark remains as biostratigraphic tool is limited, due to their current poor taxonomic and relatively broad temporal distribution. [ABSTRACT FROM AUTHOR]

This paper investigates the much-debated Jurassic/Cretaceous (J/K) boundary as well as the Early Cretaceous climate using palynomorphs of the Chichali Formation, Upper Indus Basin, North Pakistan. Based on the palynostratigraphy, two dinoflagellates and one spore/pollen assemblage are recorded, suggesting a Kimmeridgian to Valanginian age for the sediments of the Chichali Formation. The palynostratigraphic results further suggest that the Tithonian to Berriasian strata are truncated along the J/K boundary. The warm and humid conditions are supported by the consistent dominance of ferns corresponding to the Schizaeaceae and the intermittent appearance of herbs from Gleicheniaceae. Such climatic conditions are further supported by the consistent presence of evergreen trees with a broad leave of Cyatheaceae and Matoniaceae. The warm and humid conditions are also supported by conifers of the Araucariaceae in association with Cycadaceae. Such conditions during the Valanginian are further supported by the switch from the Bajocian–Oxfordian shallow carbonates of the Samana Suk Formation to the Kimmeridgian–Valanginain clastics of the Chichali Formation. Hence, the expansion of warm and humid tropical flora to the middle latitude (∼40°S) during the Valanginain hints strongly for global warming instead of previously suggested global cooling. Palynostratigraphic investigation shows Kimmeridgian to Valanginian age for the Chichali Formation, Upper Indus Basin, Pakistan. The J/K boundary is marked by an unconformity along which the Tithonian to Berriasian time record is missing. The reconstruction of paleovegatation indicates warm humid climate during the Valanginian instead of previously reported global cooling. [ABSTRACT FROM AUTHOR]

The morphology of the adaxial structures of cones belonging to Palissya Endlicher 1847 emend. nov. are reinterpreted based on exquisitely preserved permineralised material from the Lower Cretaceous of Queensland. Although the material was not found in situ, it likely derives from the Orallo Formation, which is Valanginian in age. The cones have dual vascular bundles in each bract/scale complex, and the different tissue types in the bract and ovule/scale complex support interpretation of the cone as a compound structure. Since the early twentieth century it has been widely accepted that each ovule is surrounded by a cup-shaped structure, but the detailed morphology of the “cup” has hitherto been unclear. These new three-dimensionally preserved specimens with in situ ovules are described as Palissya tillackiorum sp. nov. This study demonstrates that the “cup” is formed from a pair of thin scales that subtend but are not fused to each ovule; each pair of scales comprises a thicker outer and thinner inner scale. The organographic relationships among ovules and scales in Palissya show a high degree of synorganisation. The adaxial surface of the bract/scale complex has 2–6 pairs of erect (orthotropous) ovules. The ovule/scale units are arranged symmetrically in two parallel rows on either side of the midline of the bract/scale. Individual ovule/scale units are comparable to those seen in extant Podocarpaceae and Taxaceae. The ovules are thin-walled and are interpreted to have a single integument and a non-thickened (non-lignified) micropyle. These new insights allow reinterpretation of material previously referred to Palissya. A new species is described from Yorkshire, England, as P. harrisii C.R. Hill ex Pattemore & Rozefelds sp. nov. All species based on well preserved cones are reconsidered herein: P. sphenolepis (Braun 1843) Nathorst 1908 emend. Florin 1958, P. elegans Parris, Drinnan & Cantrill 1995 emend. nov., P. bartrumii Edwards 1934 emend. nov., P. antarctica Cantrill 2000 and P. hunanensis Wang 2012. Palissya ovalis Parris et al. 1995 differs structurally from Palissya and is transferred to Knezourocarpon Pattemore 2000 emend. nov. Representatives of this genus may superficially resemble those of Palissya in compressions and impressions, and their congeneric status has been previously suggested; hence its inclusion in this study. Knezourocarpon has adaxial processes that are positioned in two parallel rows but it lacks ovules and paired lateral scales that formed a cup-shape, and its processes attach directly to a central vascular trace. The improved understanding of Palissya’s morphology allows for definite separation of these genera, although the higher-order affiliation of Knezourocarpon remains unclear.

Metriorhynchid crocodylomorphs were an important component in shallow marine ecosystems during the Middle Jurassic to Early Cretaceous in the European archipelago. While metriorhynchids are well known from western European countries, their central and eastern European record is poor and usually limited to isolated or fragmentary specimens which often hinders a precise taxonomic assignment. However, isolated elements such as tooth crowns, have been found to provide informative taxonomic identifications. Here we describe two isolated metriorhynchid tooth crowns from the upper Valanginian (Lower Cretaceous) of the Štramberk area, Czech Republic. Our assessment of the specimens, including multivariate analysis of dental measurements and surface enamel structures, indicates that the crowns belong to two distinct geosaurin taxa (Plesiosuchina? indet. and Torvoneustes? sp.) with different feeding adaptations. The specimens represent the first evidence of Metriorhynchidae from the Czech Republic and some of the youngest metriorhynchid specimens worldwide. [ABSTRACT FROM AUTHOR]

This paper describes a petrified trunk collected from a conglomerate bed of the Springhill Formation (Berriasian-Valanginian) in the Estancia El Álamo locality, Santa Cruz Province, Argentina. The fossil trunk is classified within the ubiquitous genus Agathoxylon and the wood anatomy shows a close affinity to that of Araucariaceae. This Patagonian wood has a distinct combination of anatomical characteristics unique among all known species from the Jurassic and Cretaceous of Western Gondwana allowing to diagnose a new fossil taxon Agathoxylon mendezii sp. nov. Sedimentological and megafloristic proxies of the Springhill Formation suggest that Agathoxylon mendezii sp. nov. grew under a warm and wet climate, which indicates a subtropical to temperate palaeoenvironment. However, the large number of frost rings in the earlywood of this araucarian tree suggests that the palaeoenvironment at Estancia El Álamo was subjected to recurrent disturbances, most likely caused by regional continuous volcanic activity originating from volcanoes located far away to the west. This activity would have produced periodic stratospheric veils that promoted rapid decreases in surface air temperature; the wood response to such stressful conditions would have been the formation of numerous (at least five) frost rings. Although recurrent eruptions in Patagonia during the Early Cretaceous are well recorded, this study is the first to register eruptions recorded in a coniferous wood. [ABSTRACT FROM AUTHOR]

Abstract The Early Cretaceous Weissert event, characterized by a positive carbon isotope excursion and coincident with the Paraná‐Etendeka volcanism, saw a biogeochemical chain of events that ultimately led to an increase in carbon burial. A conclusive link between the Paraná‐Etendeka volcanism and its impact upon the environment remains, however, elusive. Here we reconstruct temperature through the Weissert event from Mg/Ca ratios of belemnites from the Vocontian Trough (France) and SE Spain and use carbon isotopes to link our temperature reconstruction to marine records of carbon cycling. We provide evidence that the Paraná‐Etendeka volcanism, unlike some large igneous provinces, did not cause a climate warming. The case can be made for cooling in the last stages of the Weissert event, which possibly reflects substantial CO2 drawdown. In the absence of warming and consequent accelerated hydrological cycling and the relatively long duration of the eruptive phase of the Paraná‐Etendeka, an alternate trigger for increased fertilization of the oceans is implicated.

This article examines the geological and stratigraphic context of several types dinosaur tracks discovered in Lower Cretaceous deposits exposed in the vicinity of city of Kislovodsk (Caucasian Spa Country; Stavropol Krai). The tracks occur on the bedding surfaces of Lower Cretaceous (Valanginian) limestones, dolostones and marls. Two track morphotypes are described. Some ideas are proposed on the paleoclimatic and environmental conditions in the region during Early Cretaceous times. We suggest that the tracks were produced in a coastal plain in the littoral zone of a marine basin (possibly, a brackish lagoon) during a warm, seasonally dry climate. [ABSTRACT FROM AUTHOR]

The first Early Cretaceous (Valanginian-Hauterivian) ammonite fauna from the lower part of the Kościeliska Marl Formation (Wściekły Żleb Member) of the Lower Sub-Tatric (Krížna) Nappe, in the Lejowa Valley of the Tatra Mountains are described. The fauna is precisely placed in the succession and consists of five species: Olcostephanus densicostatus, Spitidiscus cf. cankovi, Criosarasinella cf. subheterocostata, Crioceratites primitivus, and Crioceratites coniferus and additionally an aptychus Didayilamellaptychus seranonis. Remarkable are the valves of anomiid bivalves attached to body chamber of large size heteromorph ammonite C. primitivus. Moreover, a variety of stratigraphically important organic-walled dinoflagellate cysts are recovered from this locality. Dinoflagellates: Cymososphaeridium validum, Circulodinium vermiculatum, and representatives of Bourkidinium define the Upper Valanginian-Lower Hauterivian Sentusidinium sp. A Dinocyst Subzone of the Cymososphaeridium validum Zone. The character of deposits, the palynofacies, and associations of dinoflagellate cysts indicate a calm marine outer neritic environment. [ABSTRACT FROM AUTHOR]

Cladodontomorphii represents an archaic clade of chondrichthyan fishes characterised by distinct tooth morphologies referred to as the cladodont type. This group of cartilaginous fishes first occurred during the early Palaeozoic Era as revealed from the fossil record and were long thought to have gone extinct at the Permian-Triassic mass extinction event. However, a recently reported chondrichthyan tooth assemblage from the Early Cretaceous of France suggests that cladodontomorphs might have survived the catastrophic events at the Permian-Triassic boundary, probably by occupying deep-sea refuge environments. Here, we describe two new chondrichthyan genera based on isolated teeth recovered from Valanginian (Early Cretaceous) deep-water deposits of Austria, including a total of three new species tentatively assigned to the cladodontomorph families Falcatidae (Cretacladoides ogiveformis gen. et sp. nov. and C. noricum sp. nov.) and Ctenacanthidae (Natarapax trivortex gen. et sp. nov.). In addition, an enameloid microstructure analysis had led to the identification of a distinct multilayered enameloid including a parallel-, tangled-, and radial-bundled enameloid, whose phylogenetic distribution within Chondrichthyes is here discussed in detail, leading to the conclusion that the herein described cladodont-like taxa, together with those reported from the French Early Cretaceous might be closely related to ancient Palaeozoic taxa. The ZooBank electronic publication LSID is: urn:lsid:zoobank.org:pub:C06FD718-F54F-4C57-A45E-8C0D7CC8EB83 [ABSTRACT FROM AUTHOR]

A regional sedimentological and sequence stratigraphic analysis is presented in this paper to provide new insights into the morphological complexity and sedimentary mechanisms of unconformities giving shape to basin margins. Although the development of unconformities entails significant sediment delivery to be considered when analysing 'source to sink' systems, as well as large palaeogeographical changes related to basin reconfiguration episodes, the complexity that unconformities can reveal towards basin margins has been scarcely explored. A sedimentological and architectural analysis combining outcrop and subsurface datasets shows five palaeoenvironmental evolutionary stages and four key stratigraphic surfaces in a constrained ca 2 Ma Valanginian interval on the southern margin of the Neuquén back‐arc basin (Argentina). A complex‐type subaerial unconformity was identified, composed in turn of two subaerial unconformities exhibiting both single and composite motifs, different morphologies and facies shifts representative of large palaeogeographical changes. In the studied stratigraphic interval, two erosional stages occur linked to combinations of exclusively non‐marine‐driven processes involved in unconformities developing. The two subaerial unconformities differ in nature and distribution, representing a novel case of complex unconformities and stratigraphic architectures in non‐marine lowstand wedges. The Valanginian complex subaerial unconformity entails a high diachroneity along strike and depositional dip, implying that the hiatus created in landward settings occurred during relative sea‐level fall and rise stages during a period longer than in basinward areas. Disagreeing with classical sequential models, two third‐order sequence components of a complex lowstand wedge are preserved in proximal settings. Subsidence‐controlled accommodation and interplay between second‐order and third‐order cycles were combined, increasing the prospects of sediment storage and preservation potential of composite sequences towards landward areas. This work improves current comprehension about complex subaerial unconformities formation and related lowstand architectures in proximal settings, providing criteria to understand and revaluate lowstand wedge geometries, particularly for more complex examples, such as the case reported in this contribution. [ABSTRACT FROM AUTHOR]

The Early Cretaceous (probably Berriasian – Valanginian) Whitchurch Sands Formation of Oxfordshire and Buckinghamshire, English South Midlands, was deposited as coastal-marine and alluvial sediment along the northern edge of the Wessex Basin. The type succession at Whitchurch in Buckinghamshire includes a marine horizon, probably of Berriasian age. Alluvial sediments dominate the formation elsewhere and are tentatively linked to mid-Valanginian uplift of the nearby London – Brabant Massif. The Valanginian alluvial plain is thought to have bordered a coastal lagoon and barrier complex, accounting for non-marine faunas in the Whitchurch Sands Formation, and limiting seawater influx into the Weald Basin of south-east England, from a South Midlands seaway. Detrital and palaeobiological data from the Whitchurch Sands Formation and type Wealden (Weald Basin) suggests a connection between the seaway and the East Midlands Shelf, through much or all of the Valanginian – early Aptian interval. [ABSTRACT FROM AUTHOR]

The paper deals with newly discovered Valanginian-Hauterivian fauna of heteromorphic ammonites (Ancyloceratina) from locality south of the village of Leše above the Meža River valley (North Karavanke Mountains). Fossils were recovered from the pelagic limestone. Among the studied heteromorphic ammonites are Lower Cretacaoeus species Himantoceras trinodosum (Upper Valanginian) and Crioceratites cf. nolani (Hauterivian). Based on the accompanied ammonites (Ammonitina) from the outcrop, we biostratigraficaly confirm the presence of Lower Cretaceous ammonites fauna in the Northern Karavanke Mountains. This is also the first report on heteromorphic ammonites in Slovenia. [ABSTRACT FROM AUTHOR]

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

Euthymi, Crassicostatum and Callisto ammonite subzones, correlable with Paramimounum, Picteti, and Alpillensis subzones and probably with the Late Berriasian Otopeta Subzone of the Boissieri Standard Zone have been recognized in calcareous clays of the Berriasian-Valanginian boundary sequence in the Feodosiya district (eastern Crimea). The ammonite Leptoceras studeri (Ooster) suggests Late Berriasian to Early Valanginian age. Geomagnetic polarity indicates M16-M14r magnetozones. Therefore, the base of the Valanginian sequence in eastern Crimea should be placed within the M14r magnetozone.

The morphology of the adaxial structures of cones belonging to Palissya Endlicher 1847 emend. nov. are reinterpreted based on exquisitely preserved permineralised material from the Lower Cretaceous of Queensland. Although the material was not found in situ, it likely derives from the Orallo Formation, which is Valanginian in age. The cones have dual vascular bundles in each bract/scale complex, and the different tissue types in the bract and ovule/scale complex support interpretation of the cone as a compound structure. Since the early twentieth century it has been widely accepted that each ovule is surrounded by a cup-shaped structure, but the detailed morphology of the "cup" has hitherto been unclear. These new three-dimensionally preserved specimens with in situ ovules are described as Palissya tillackiorum sp. nov. This study demonstrates that the "cup" is formed from a pair of thin scales that subtend but are not fused to each ovule; each pair of scales comprises a thicker outer and thinner inner scale. The organographic relationships among ovules and scales in Palissya show a high degree of synorganisation. The adaxial surface of the bract/scale complex has 2–6 pairs of erect (orthotropous) ovules. The ovule/scale units are arranged symmetrically in two parallel rows on either side of the midline of the bract/scale. Individual ovule/scale units are comparable to those seen in extant Podocarpaceae and Taxaceae. The ovules are thin-walled and are interpreted to have a single integument and a non-thickened (non-lignified) micropyle. These new insights allow reinterpretation of material previously referred to Palissya. A new species is described from Yorkshire, England, as P. harrisii C.R. Hill ex Pattemore & Rozefelds sp. nov. All species based on well preserved cones are reconsidered herein: P. sphenolepis (Braun 1843) Nathorst 1908 emend. Florin 1958, P. elegans Parris, Drinnan & Cantrill 1995 emend. nov., P. bartrumii Edwards 1934 emend. nov., P. antarctica Cantrill 2000 and P. hunanensis Wang 2012. Palissya ovalis Parris et al. 1995 differs structurally from Palissya and is transferred to Knezourocarpon Pattemore 2000 emend. nov. Representatives of this genus may superficially resemble those of Palissya in compressions and impressions, and their congeneric status has been previously suggested; hence its inclusion in this study. Knezourocarpon has adaxial processes that are positioned in two parallel rows but it lacks ovules and paired lateral scales that formed a cup-shape, and its processes attach directly to a central vascular trace. The improved understanding of Palissya's morphology allows for definite separation of these genera, although the higher-order affiliation of Knezourocarpon remains unclear. [ABSTRACT FROM AUTHOR]

Ashdown Brickworks, near Bexhill, East Sussex, has produced a large number of vertebrate fossils from the Wadhurst Clay Formation, part of the Wealden Supergroup (Hastings Group; Valanginian; Lower Cretaceous). Here we describe the microvertebrate fauna of the 'conglomerate bed', representing a rich sample of taxa. While most of the recovered teeth and bones are abraded, some heavily, most can be identified to species level. The taxa include four species of hybodont sharks (Egertonodus basanus , Planohybodus ensis , Polyacrodus parvidens , P. brevicostatus), three taxa of bony fishes (an unidentified Lepidotes -like semionotiform, the pycnodontiform Ocloedus , and an albuliform), three taxa of crocodyliforms (the goniopholid Hulkepholis , a bernissartiid, and the atoposaurid Theriosuchus), and the theropod dinosaurs Baryonyx and an allosauroid. Sediments of the Wadhurst Clay Formation as a whole indicate freshwater to very slightly brackish-water environments of deposition, and the mainly aquatic time-averaged mixture of fishes and tetrapods recovered from the 'conglomerate bed', together with isolated terrestrial species, confirms this interpretation. [ABSTRACT FROM AUTHOR]

Abstract The oldest dating of the earliest Cretaceous transgression in S Aquitaine (SW France) was long considered Aptian. In 1954, Cuvillier and Debourle report from the subsurface the find of a microfossil assemblage that they ascribe to the Valanginian. In 1968, Schroeder and Poignant cast some doubts on the identifications and state that this assemblage is characteristic of the Barremian, not of the Valanginian. Revision of the benthic foraminifers and Dasycladales from the bottom section of the Cretaceous at Lacq 104 borehole demonstrates that the oldest records of the transgression, per definition diachronous, are probably late Hauterivian in age. Due to the lack of any evidence for the occurrence of Berriasian or Valanginian strata, the hiatus related to erosion and non-deposition is there assumed to span the lower part of the Hauterivian, the Valanginian, most if not all of the Berriasian and possibly the uppermost part of the Tithonian. [ABSTRACT FROM AUTHOR]

Abstract The Tithonian–Valanginian interval is subdivided into 5 biozones (zones and subzones) combining mostly large benthic foraminifera and "calcareous" green algae, which are typical of photozoan assemblages from the shallow-water carbonate facies of the Tethysian realm. This dual zonation is calibrated on a sequence stratigraphic framework for the Jura Mountains where earlier findings of ammonites and calpionellids are plotted. The microfossil diversity was low in the Tithonian–early Berriasian times; then it significantly increased over the middle–late Berriasian times before a first extinction event at the Berriasian/Valanginian boundary followed by a second extinction event in the early Valanginian times. The lower/middle Berriasian and the Berriasian/Valanginian boundaries can be traced consistently from West to East through the whole Tethysian realm. By contrast, the upper Tithonian and the lower Berriasian cannot be distinguished. Because the location of the Jurassic/Cretaceous system boundary has been pending a decision of the International Commission on Stratigraphy since 1975, this survey provides one more argument to abandon the early 20th century Kilian's view which placed it at the Tithonian/Berriasian stage boundary, and to return it to the original 19th century Orbigny's and Oppel's view, i.e., back at the Berriasian/Valanginian stage boundary. [ABSTRACT FROM AUTHOR]

Abstract A new dicraeosaurid sauropod, Pilmatueia faundezi gen. et sp. nov. from the Mulichinco Formation (Valanginian, Lower Cretaceous, Neuquén Basin, Argentina) is based on isolated skeletal remains collected from a single stratigraphic level, relatively close to each other, with unquestionable dicraeosaurid features in the axial elements. Pilmatueia faundezi is diagnosed by a unique combination of several features that include cervico-dorsal vertebrae with dorsoventrally oriented ridges on the anterior surfaces of the anterior centrodiapophyseal laminae, and posterior dorsal vertebrae with deep fossae at the bases of the bifid neural spines separated by a thick, low, sagittal lamina. Pilmatueia is recovered as the sister taxon of the late Early Cretaceous Amargasaurus cazaui. Pilmatueia increases our knowledge about the record of sauropods during the Valanginian, a period in which dinosaur diversity worldwide is poorly known. Highlights • A new taxon of the intriguing sauropod family Dicraeosauridae, Pilmatueia faundezi is described. • Pilmatueia is the first recognized Valangininan dicraeosaur sauropod taxon. • Pilmatueia represents the earliest recorded Cretaceous dicraeosaurid sauropods. • Pilmatueia was part of a South American Upper Jurassic-Lower Cretaceous dicraeosaurid radiation. [ABSTRACT FROM AUTHOR]

Until now there have been no formal descriptions of pterosaur remains from the Cliff End Bone Bed of the Lower Cretaceous (Valanginian), Wadhurst Clay Formation, Wealden Supergroup, of south-east England. This horizon yields abundant vertebrate material representing both aquatic and terrestrial taxa and recent examination of a large collection of vertebrate remains obtained by a private collector has led to the discovery of two isolated pterosaur teeth, both referable to the same taxon. Tooth crown morphology differs from that of teeth informally reported from the Wadhurst Clay Formation and attributed to ornithocheirids in being triangular in lingual and labial view, labiolingually compressed with well-defined carinae on the mesial and distal margins and with a low basal cingulum. Their possible affinities are discussed, and they are tentatively, but with some uncertainty, attributed to an istiodactylid. If this attribution is correct, they represent the earliest record of Istiodactylidae to date. [ABSTRACT FROM AUTHOR]

Investigations on the S’Ozzastru section from the northern part of the Mt Albo area (central-eastern Sardinia, Italy) for integrated litho- bio- and chemostratigraphy allowed the identification of the Valanginian Weissert Oceanic Anoxic Event (OAE), testified by a positive carbon isotope excursion (CIE). The section, which represents the deepest-water succession of the Valanginian in Sardinia, is composed of the Schiriddè Limestone followed by the Siniscola Marl, both proposed as new lithostratigraphic units. The presence among the ammonites of Busnardoites campylotoxus allows the attribution of the Schiriddè Limestone to the upper Lower Valanginian Campylotoxus Zone auctt. (= Karakaschiceras inostranzewi Zone of Reboulet et al. 2014). Further characterization of this unit was not possible since it is barren/almost barren of nannofossils. The Siniscola Marl can be ascribed to the lower Upper Valanginian on the basis of the ammonite fauna indicating the Verrucosum Zone, and of the nannofossil content suggesting the Zone NK3. The carbon isotope record in the Siniscola Marl is characterized by a positive excursion with values up to 2.98 ‰. In the nannofossil assemblages, nannoconids are not particularly abundant and are found, among others, together with C. oblongata, D. lehmanii, and pentaliths. The scarcity of nannoconids is regarded as a biostratigraphic support for the identification of the Weissert OAE, as it possibly reflects the “nannoconid decline” interval which characterizes this event. The end of the Weissert OAE CIE is not recorded probably because of tectonic causes.

Investigations on the S'Ozzastru section from the northern part of the Mt Albo area (central-eastern Sardinia, Italy) for integrated litho- bio- and chemostratigraphy allowed the identification of the Valanginian Weissert Oceanic Anoxic Event (OAE), testified by a positive carbon isotope excursion (CIE). The section, which represents the deepest-water succession of the Valanginian in Sardinia, is composed of the Schiriddè Limestone followed by the Siniscola Marl, both proposed as new lithostratigraphic units. The presence among the ammonites of Busnardoites campylotoxus allows the attribution of the Schiriddè Limestone to the upper Lower Valanginian Inostranzewi Zone of Reboulet et al. 2014. Further characterization of this unit was not possible since it is barren/almost barren of nannofossils. The Siniscola Marl can be ascribed to the lower Upper Valanginian on the basis of the ammonite fauna indicating the Verrucosum Zone, and of the nannofossil content suggesting the Zone NK3. The carbon isotope record in the Siniscola Marl is characterized by a positive excursion with values up to 2.98 %. In the nannofossil assemblages, nannoconids are not particularly abundant and are found, among others, together with C. oblongata, D. lehmanii, and pentaliths. The scarcity of nannoconids is regarded as a biostratigraphic support for the identification of the Weissert OAE, as it possibly reflects the “nannoconid decline" interval which characterizes this event. The end of the Weissert OAE CIE is not recorded probably because of suppression of the upper part of the succession for tectonic causes. [ABSTRACT FROM AUTHOR]

Abstract The 6th Kilian Group meeting of the IUGS Lower Cretaceous Ammonite Working Group (the Kilian Group) was held in Vienna, Austria, 20th August 2017. The Group mainly discussed the standard zonation that is suitable for and based mainly on ammonite data of the Mediterranean Province of the Mediterranean–Caucasian Subrealm (Tethyan Realm). Some changes have been made on three stages. The uppermost part of the Berriasian is now characterised by the Tirnovella alpillensis Zone, that is subdivided into a lower T. alpillensis Subzone and an upper “Thurmanniceras” otopeta Subzone; the T. alpillensis (Sub-)Zone is here defined by the first appearance datum (FAD) of the index-species. For the Valanginian, the Neocomites premolicus Subzone is introduced in the lower part of the “ Thurmanniceras ” pertransiens Zone. The FAD of N. premolicus occurs at the base of the “ T. ” pertransiens Zone. So this subzone starts at the base of the “ T.” pertransiens Zone and provisionally ends at the last occurrence of N. premolicus as the upper part of the zone is not characterised by a subzone for the moment. For the Barremian, the former Holcodiscus fallax , Nicklesia didayana , Heinzia communis , Subtorcapella defayae , Coronites darsi , Heinzia caicedi and Anglesites puzosianum horizons have been abandoned. In agreement with systematic positions, the term “ auctorum ” is deleted for Taveraidiscus hugii, the index-species of the first zone of this stage. The Kotetishvilia compressissima Zone is subdivided into a lower Holcodiscus fallax Subzone and an upper Holcodiscus caillaudianus Subzone. The Barrancyloceras barremense Subzone (upper subzone of the Toxancyloceras vandenheckii Zone) is replaced by the Gassendiceras alpinum Subzone. The Imerites giraudi Zone is kept but its base should be now defined by the FAD of I. dichotomus, which marks the inception of the genus Imerites. For certain stratigraphic intervals the Group discussed and in some cases strengthened the previous correlations between the standard Mediterranean zonation with the different ammonite zonal schemes of other provinces and realms. Some members of the Group presented the possibility of using regional stages as secondary standards, in accordance with the recommendations of the International Commission on Stratigraphy. The report concludes with an appreciation of the French ammonitologist Jean-Pierre Thieuloy deceased in 2017, the nomination of a vice-chair, membership, future work and next meeting of the Kilian Group. Highlights • Summarizing the current state of the Mediterranean standard ammonite zonation. • Outlines the outstanding biostratigraphic and palaeobiogeographic problems. • The standard zonation was modified for the Berriasian, Valanginian, and Barremian. • The standard zonation was compared with the zonal schemes of other realms. • A tribute to the French ammonitologist J-P Thieuloy (deceased in 2017) is made. [ABSTRACT FROM AUTHOR]

Lower Cretaceous (Valanginian) dendritic microfabrics occur in karstic cavities within fine-grained shallow-marine platform carbonates at San Lorenzello, southern Italy. They form dense micritic masses and clusters, generally oriented perpendicularly to cavity surfaces, surrounded by layered sparry cement. Individual dendrites, typically sub-millimetric in size, have highly irregular margins and form distinctive shrub-like masses ranging from compact and squat, to elongate and highly branched. The centimetric and irregularly elongate cavities appear to have formed through subaerial exposure, and are almost entirely filled by the micritic dendrites and associated sparry crusts. In size, shape and micritic composition, the dendrites broadly resemble a variety of similar fabrics, including hot spring travertine shrubs and calcified microfossils such as Cambrian Angusticellularia , which has analogs in present-day lacustrine calcified cyanobacteria. However, the San Lorenzello dendrites differ in occupying small cavities. This cryptic microkarstic dripstone setting, together with the often regular spacing and appearance of these dendritic fabrics, may be more consistent with an abiotic origin. These comparisons underscore the challenge of interpreting microdendritic carbonates fabrics in general. [ABSTRACT FROM AUTHOR]

Further to the work published by Néraudeau et al. six years ago, palynological matter recovered from the lignitic bone bed of Angeac in Charente (south-west France) has been re-examined in order to provide more evidence of its age, the previous Hauterivian–Barremian interpretation being regarded as controversial. The samples come from four sedimentological units, An2–An5, which together yielded an assemblage of 34 species, taxonomically dominated by palaeoecologically significant lygodiaceous verrucate spores, including eight species attributable to the genus Concavissimisporites and three species of Trilobosporites . A few bisaccate pollen grains, including Vitreisporites pallidus , have been recovered, but the gymnospermous pollen spectrum is clearly dominated by the cheirolepidiaceous genus Classopollis , its abundance diminishing progressively upwards from units An4 to An2. The great abundance and diversity of verrucate forms, along with the presence of other spores typical of Lower Cretaceous deposits, such as Aequitriradites verrucosus , and the scarcity of specimens referable to Cicatricosisporites , render this assemblage most similar to those of the Hastings Group of southern England and the Bückeberg Formation in north-western Germany. The time of deposition is, therefore, more likely to have been Berriasian–Valanginian rather than Hauterivian–Barremian, as previously stated. The associated small assemblage of megaspores is consistent with this determination. Except for Trilobosporites and Concavissimisporites , the use of several other genera commonly applied to Mesozoic verrucate spores, such as Converrucosisporites and Impardecispora , is considered unnecessary. To support this assertion, a Principal Components Analysis has been carried out on 120 verrucate spores from sedimentological units An2–4, taking into account ten morphological variables. The results show that specimens attributable to Trilobosporites are well be separated from the main cluster, which corresponds to Concavissimisporites , underlining the futility of using more than two genera for the species concerned. [ABSTRACT FROM AUTHOR]