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The Lower Cretaceous charophyte flora from the Wealden of the Cuchía section (Barremian, North Cantabrian Basin, northern Spain) was investigated. This locality represents the northernmost charophyte flora on the Iberian microplate. Twenty-one charophyte taxa were identified and two distinct charophyte assemblages, belonging to two different biozones, were recognized. The lower part (beds 1–6) of the studied section yielded the first charophyte assemblage composed of the species Echinochara lazarii , Atopochara trivolvis var. triquetra , Globator mallardii var. trochiliscoides , Clavator grovesii var. combei , Clavator harrisii var. dongjingensis , C. harrisii var. harrisii , C. calcitrapus var. jiangluoensis , Ascidiella stellata var. lata , A. triquetra , Hemiclavator neimongolensis var. neimongolensis , H. neimongolensis var. posticecaptus , aff. Mesochara harrisii , Porochara gr. kimmeridgensis subgr. kimmeridgensis , Clavatoraxis sp., and Favargerella aquavivae. This charophyte assemblage belongs to the Eurasian "Hemiclavator neimongolensis var. neimongolensis" biozone, assigned to the upper lower Barremian–lower upper Barremian. The upper part (beds 7–12) of the studied section yielded the second charophyte assemblage composed of the species E. lazarii , A. trivolvis var. triquetra , A. trivolvis var. trivolvis , G. mallardii var. biutricularis , C. grovesii var. jiuquanensis , C. harrisii var. dongjingensis , C. harrisii var. harrisii , C. harrisii var. reyi , C. calcitrapus var. calcitrapus , H. neimongolensis var. neimongolensis , H. neimongolensis var. posticecaptus , aff. Mesochara harrisii , Munieria grambastii , Clavatoraxis sp., and Favargerella aquavivae. This charophyte assemblage is correlated to the Eurasian "Clavator grovesii var. jiuquanensis" biozone, assigned to the upper Barremian–lower Aptian. Considering that the Wealden at Cuchía section is capped by the lower Aptian calcarenites (Umbrera Formation), this series is chronostratigraphically constrained to the upper lower Barremian–upper Barremian, instead of Hauterivian–Barremian as previously thought. The Cuchía charophyte flora has some of the highest species diversity from Wealden-type facies worldwide. The charophyte hotspot of Cuchía displays a strong similarity with the previously reported contemporaneous flora diversity hotspot in the Maestrat Basin (eastern Spain), which to date shows the most diverse Barremian charophyte assemblage worldwide (33 taxa). Our results further support the significant role of the Iberian Peninsula in the evolution of Lower Cretaceous charophytes within the Central Tethyan Archipelago bioprovince. [ABSTRACT FROM AUTHOR]

Cephalopod mandibles are rare in the Bohemian Cretaceous Basin (BCB) of Central Europe, occurring only as isolated jaw elements, the sole exception being a specimen of Yezoites bladenensis found with a lower jaw in situ in the second half of the 19th century. Here, we present a second record, a specimen of the acanthoceratoid ammonite Prionocyclus germari (Upper Cretaceous, upper Turonian). The ammonite preservation shows similarities to ammonoids from Solnhofen-type Lagerstätten, including phosphatised siphuncles, while the flattened ammonite conch is poorly preserved or fully dissolved. The lower jaw of P. germari is referred to the genus Praestriaptychus. Linking the jaw apparatus with an index ammonite taxon of the uppermost Turonian fills a gap in our knowledge of Upper Cretaceous acanthoceratoid ammonite jaw anatomy. The preservation of altered (secondarily carbonised) organic matter has been revealed by Raman spectroscopy analysis at the tip of the aptychus. The associated fauna and flora, consisting of complete crustaceans, fish, chondrichthyans and gymnosperm plant remains, reflect an unusual and unique preservational/taphonomic window within the BCB. [ABSTRACT FROM AUTHOR]

Eight echinoid species are described from Upper Cretaceous marl-limestone alternations from a temporary outcrop in the neighbourhood of the village of Mompia (northern Cantabria, Spain): Temnocidaris (Stereocidaris) mengaudi , Pseudoholaster pachecoi , Roweaster cantaber , Micraster turonensis , Micraster mengaudi , Bolbaster micranthus and two newly described species: the phymosomatoid Cosmocyphus cantaber sp. nov. and the micrasterid Micraster quebrada sp. nov. The three Micraster species reveal an astonishing and extreme degree of intraspecific variation, in particular the degree of inflation of the test. This has not yet been detected in any other spatangoid species before. The majority of reported echinoids are restricted to the working area, and hence are likely endemic to this area. An integrated stratigraphic approach using ammonites, inoceramid bivalves, calcareous nannofossils and stable carbon isotopes localises the echinoid assemblage in the upper middle and lower upper Santonian. • Eight echinoid species are described from the middle and late Santonian of northern Cantabria, N Spain. • Two new species from the family Phymosomatidae and Micrasteridae, respectively, are reported. • The Micraster species show extreme, so far unknown, intraspecific variation in particular their test shape. • Regional stratigraphy is improved by using calcareous nannofossils, ammonites, inoceramids and stable carbon isotopes. [ABSTRACT FROM AUTHOR]

Based on representatives of the Late Cretaceous genus Gauthieria ( Gauthieria radiata – Gauthieria spatulifera – Gauthieria princeps ), ontogenetic trajectories within the family Phymosomatidae are described for the first time. Due to shared similarities in their ontogenetic development, an intimate evolutionary relationship must be assumed. This interpretation is most supported by analyses of the development in the ambulacral plating pattern (alternation of simple plates and compound plates), which is not commonly found among the Phymosomatoidae. This pattern, however, is present among all three species during development. The developmental trajectories of 8 further characters were included in this study (arrangement of the adapical pore pairs, number of pore pairs, pore pair numbers in ambital ambulacral plates, number of interambulacral plates, peristomal opening, apical opening diameter, test height, radial ornament of the areoles). The evolution in this lineage is characterised by several different heterochronic processes, which suggest a dissociated heterochronic evolution, indicating a developmental modularity. Additionally, the systematic treatment of G. princeps is discussed on account of the presented results. [ABSTRACT FROM AUTHOR]

An extensive pockmark field with associated methane-seep carbonates has recently been reported from the late Albian (Lower Cretaceous) Ubidepea Mudstone of the Black Flysch Group in the Basque Country, northern Spain, but the exact pathways of the migrating methane-rich fluids remained elusive. Here we provide petrographic, stable carbon and oxygen isotope evidence that abundant crustacean burrows in the surrounding mudstone, preserved as the trace fossil Thalassinoides , and the seep carbonates themselves have acted as long-lasting fluid conduits in this system. The Thalassinoides infill generations show a diagenetic parasequence often starting with a distinctive lining, followed by one to several phases of cementing of the burrow walls and burrow infills, and finally late diagenetic sparry calcite that filled the remaining open cavities and conduits. The micrite cementing the burrow walls shows negative δ 13 C values similar to those reported from the seep carbonates, indicating that methane oxidation was involved in their precipitation, rather than (or in addition to) the oxidation of other organic matter. Even the late diagenetic sparry calcite shows δ 13 C values as low as −30.4‰ (versus PDB), providing evidence that these burrows served as fluid conduits for an extended period of time. Our study supports the growing body of evidence that crustacean burrows play an important role in channeling seeping fluids in such systems. We anticipate that this phenomenon is much more widespread than currently appreciated, especially in examples where other types of fluid conduits are absent. [ABSTRACT FROM AUTHOR]

Little information exists on the distribution of calcareous dinoflagellate cysts from the Turonian (Upper Cretaceous) of Germany, and the first taxonomic assessment of late Turonian calcareous dinoflagellate cysts from the Salder Formation (NW Germany, Lower Saxony Basin) is a first step to close this gap. Ca. 11.000 calcareous dinoflagellate cysts were considered for this study, representing seven taxa only. The dominant taxon is Pithonella , mainly represented by Pithonella sphaerica and Pithonella ovalis , while Pithonella cardiiformis and Pithonella discoidea are rare. The species Pithonella spiralis n. sp. is newly described. Non-pithonellid c-dinocysts are represented by Normandia circumperforata and Pirumella sp. The late Turonian c-dinocyst diversity of the NW German shelf sea is extremely low compared with the Early Cretaceous species richness in the same area. The diversity drop is explained to result from a Turonian nutrient crisis, caused by the drowning of source areas of nutrient input during the early Late Cretaceous sea-level highstand. [ABSTRACT FROM AUTHOR]

Abstract: The phylogenetic origin of the Sepiida is still unclear. The presumed derivation from diplobelid belemnoids can be tested by comparison of their initial chambers (protoconchs). The first investigation of a juvenile phragmocone of the diplobelid Conoteuthis hayakawai from the Cenomanian of Hokkaido (northern Japan) yielded surprising insights into the internal protoconch morphology of the Diplobelida. The Conoteuthis protoconch exhibits in many aspects a mosaic of the belemnitid and the spirulid protoconch types. Whereas the sepiid protoconch represents most probably a modification of the spirulid type, the Conoteuthis protoconch is unique in having a closed (imperforated) proseptum. Apart from this, Conoteuthis differs in many other characters from the earliest sepiids (Ceratisepia, Belosepia), which makes a closer relationship unlikely. [Copyright &y& Elsevier]

Abstract: A diverse holothurian fauna from the Upper Turonian of the Isle of Wolin (northwestern Poland), is described and assessed with respect to palaeoecology, palaeobiology and evolutionary diversification. The fauna was recovered from chalk and partly silicified chalk. A stratigraphic re-assessment of all available biostratigraphic literature permits assignment to the Subprionocyclus neptuni ammonite zonal age (late Turonian). The majority of the holothurian fauna consists of apodid, aspidochirotid, and elasipodid species. The part of the fauna described here consists of sclerite species of three different Recent families of the Apodida. Two new forms, Calcancora venusta sp. nov. and Rigaudites ernsti sp. nov. (Synaptidae: Rynkatorpinae), are described, figured and discussed. [Copyright &y& Elsevier]

Abstract: The “An der Schanz quarry” near Burgberg exhibits parts of the Helvetic Seewen Formation. Its base is dated as Cenomanian, its top as Late Santonian by planktonic foraminifera by previous authors. A re-sampling of the section for inoceramid and δ13C stratigraphy gave an Early Coniacian age for the uppermost parts of the Seewen Formation. A literature review suggests that the top of Seewen Formation of the Allgäu (Bavaria) and Vorarlberg (Austria) is never younger than the Middle or terminal Middle Coniacian. δ13C data confirm the biostratigraphic dating by inoceramids. Furthermore, although only 28m thick, the section exhibits all important δ13C events for interbasinal correlation previously recognized in sections of England and northwestern Germany. The δ13C calibration of the LO of H. helvetica is shown to be diachronous and not of value for isochronous zonations. The Caburn δ13C event is suggested as a marker for the Middle-Upper Turonian boundary due to the concomitant FO of I. perplexus. The re-dating of the facies turnover from a calcareous biosedimentary system towards a marl dominated system (succeeding Amden Formation) is briefly compared with the situation observed in northwestern Germany, where comparable trends are mapable. [Copyright &y& Elsevier]

Abstract: New discoveries of articulated partial skeletons of teleosts from Upper Turonian strata in the Bohemian Cretaceous Basin (BCB) are described. The infrequent occurrence of articulated skeletons is discussed and compared with comparable taxa from the same time-equivalent successions in southern England. The similarity suggests links between both regions during the Late Turonian. Some palaeoecological interpretations of the fishes are provided. [Copyright &y& Elsevier]

Abstract: In the Middle East and Africa, the Cenomanian ammonite genus Neolobites occurs, partly in great abundance, in shallow marine shelf settings. The genus includes several species but it has remained uncertain to what extent these species reflect biospecies, chronospecies or morphological variants. Based on material from Jordan and Egypt, the morphological variation of Neolobites vibrayeanus is described and discussed. From the several species of Neolobites described in the literature, only N. vibrayeanus, N. fourtaui and N. peroni appear to deserve specific separation. Sedimentological and lithological data, notably the common occurrence in strata that were possibly deposited above storm wave base, suggest that Neolobites was able to inhabit shallow marine settings. In these settings, it seems to form a distinct assemblage with the nautiloid Angulithes. Although N. vibrayeanus shows morphological variability between distinct populations, local N. vibrayeanus assemblages seem to develop morphologically stable populations that show only a little morphological overlap with those of other areas. This may be the reason for the earlier taxonomic splitting. The occurrence in habitats in which other stratigraphically significant ammonites are often missing may be the reason for the previous poor dating of Neolobites assemblages. [Copyright &y& Elsevier]

Abstract: A Turonian ammonite faunule from the Shotori Mountains (east-central Iran) with Thomasites koulabicus (Kler) and Collignoniceras woollgari regulare (Haas) is recorded for the first time and briefly described. Thomasites koulabicus appears, in contrast to the widely distributed C. w. regulare, to be restricted to central East Asia. Its occurrence in east-central Iran provides new insights into the Turonian ammonite palaeobiogeography of the area. The ammonites document a Cretaceous marine transgression onto the Shotori Mountains in the central part of the Central-East Iranian Microcontinent during the Early–Middle Turonian. The nearshore character of the host sediments, a strong terrigenous input, and the intercalation of conglomerates originating from nearby cliffs suggest that at least portions of the Shotori Mountains defied inundation by the Turonian sea. This “Shotori Island” was surrounded by shelf seas and narrow oceanic basins, forming an important palaeogeographical feature in the Tethysides of the Middle East during the Late Cretaceous. [Copyright &y& Elsevier]

The north Bohemian Cretaceous (Bohemian Cretaceous Basin; Czech Republic) is located between the northern temperate areas and the Tethys. As a gateway to the Tethys, lithology, fauna and integrated stratigraphy (litho-, bio-, event, sequence, stable isotope stratigraphy) of the Upper Turonian succession in the Úpohlavy working quarry are described. Due to a large hiatus, the δ13C curve cannot be used for stratigraphic purposes at the base of the section. Up-section, the curve exhibits the well-known middle Upper Turonian positive excursion. Biostratigraphic and sequence stratigraphic subdivisions permit good correlation with other European Cretaceous basins. The inoceramid bivalve assemblage enables correlation with the US Western Interior. Palaeoceanographically, a positive peak in the δ18O curve above the hiatus indicates the upper part of the Late Turonian cooling event observed in other areas. The cooling was accompanied by a southward shift of a cool/temperate oceanic biosedimentary system, expressed by the sudden turnover from siliciclastic towards pelagic carbonate deposition. It is associated with the establishment of presumed oligotrophic conditions in the immediate vicinity of the West Sudetic Island, as indicated by the sudden decrease of macrofaunal abundance and diversity. [Copyright &y& Elsevier]

Isochronous variations of δ18O curves within several European basins indicate a period of Late Turonian climate cooling, which is characterized by two distinct cooling phases, separated by a period of climate stability. Literature data for macrofauna (ammonites, echinoids, and belemnites) indicate that the cooling phases are associated with a southward shift of taxa. Concomitant Late Turonian events (volcanism and relative sea-level changes) suggest the migration to be triggered mainly by relative sea-level falls. The inferred cooling phases are seen in context with a general cooling trend due to the decrease in Mid-Cretaceous volcanogenic CO2 emission. Short-term stagnation of cooling in the Late Turonian has been probably triggered by renewed volcanism. Due to the general high temperatures during Mid-Cretaceous times, a glacio-eustatic explanation for the coincidence of cooling and sea-level fall is considered unlikely. [Copyright &y& Elsevier]

A new pycnodont taxon, Njoerdichthys dyckerhoffi gen. et sp. nov., from the Turonian of the Lower Saxony Basin of Germany is described and its systematic positions is established based on phylogenetic analyses of three specimens using slightly altered data matrices. All analyses display some differences to previous analyses but show very similar results to each other apart from the interpretation of the position of several taxa such as, e.g., Palaeobalistum. The new pycnodontiform specimens from northwestern Germany are unambiguously identified as a derived member of Pycnodontidae with close relationships to Abdobalistum and Nursallia ? goedeli because of the unique combination of characters. One of the three specimens represents a juvenile form. Its morphological characters are limited, but it shares some characters with Njoerdichthys dyckerhoffi gen. et sp. nov. and is consequently allocated to the new taxon. The systematic placement of the new taxon, Njoerdichthys gen. nov., within Pycnodontidae is surprising since it does not display the one autapomorphic character (postparietal brush-like extension for muscle attachment) previously proposed to define this clade, but rather displays a combination of derived and homoplastic characters indicating that the definition of supra-generic taxa needs to be re-evaluated in the future by including more and new taxa. The distribution of pycnodontiform fishes in the Cretaceous appears to concur with changes in global climatic conditions, where high upper-ocean temperatures and high sea levels allow these fishes to migrate into higher latitudes as evidenced by the occurrence of the new taxon and Anomoeodus subclavatus in the Campanian of Sweden. [ABSTRACT FROM AUTHOR]