Crossing the boundary: an elasmobranch fauna from Stevns Klint,Denmark

The chondrichthyan faunas from the Danish Maastrichtian chalk and the K/T boundary clay, the Fiskeler, are described for the first time. The rich and diverse fauna discovered in the late Maastrichtian chalk experienced a massive drop in diversity prior to the boundary. However, the fauna started to recover immediately after the deposition of the impact layer during earliest Danian times and had regained much of its diversity during the first few millennia after the bolide impact. Precision sampling has made it possible to document the recovery of the fauna, which did not suffer an extinction event of the same magnitude, as apparently observed in Morocco. At Stevns Klint, only 33 per cent of the chondrichthyan fauna became extinct compared with the 96 per cent in Morocco. The drop in diversity before the boundary is attributed to a sudden change in sea level. Among the sharks found in the chalk and Fiskeler are rare species such as Parasquatina and Echinorhinus and the first representative of Nebrius in Europe.     

A high‐stress shelly fauna associated with sponge mud‐mounds in the Coniacian Arnager Limestone of Bornholm,Denmark

The benthic macrofaunas of the Upper Cretaceous chalk of NW Europe show characteristically high species‐richnesses and commonly high densities. They are predominated by bivalves, brachiopods, polychaetes, echinoids, crinoids, asteroids, sponges and towards the end of the Cretaceous also by bryozoans. The mound‐bedded chalk of the Coniacian Arnager Limestone on the island of Bornholm in the Baltic Sea, Denmark, differs from this general picture. It was deposited on a small fault block adjacent to the main Bornholm block, which was emerged during much of the Mesozoic and thus occupied a much more proximal position than most other Upper Cretaceous chalks in NW Europe. The Arnager Limestone contains a unique, exceptionally rich and well‐preserved fauna of mainly hexactinellid, lyssacinosan sponges. The low mud‐mounds are interpreted as formed by baffling and trapping of fine sediment particles by the dense sponge thickets. In contrast, the associated shelly fauna is unusually sparse, of very low richness and extremely low density, except for inoceramid bivalves. It represents a strongly depauparated version of the shelly faunas of contemporaneous chalks in NW Europe. The rare specimens of non‐inoceramid shelly species are interpreted to represent occasional successful spatfalls of benthic species from the deeper‐water chalk farther offshore in the Baltic area. The sponge mud‐mounds of the Arnager Limestone show remarkable resemblances with modern sponge mounds recently discovered on the continental shelf of western Canada. They form an important link between the well‐known older Mesozoic sponge mud‐mounds or ‘reefs’ and the modern mounds and are among the youngest examples of Mesozoic sponge mounds.     

Dinoflagellate cyst biostratigraphy of the Coniacian–Santonian (Upper Cretaceous): New data from the English Chalk

Results are presented here for the first chalk-based, high-resolution quantitative study of organic-walled dinoflagellate cysts (dinocysts) from the entire Coniacian–Santonian Chalk successions in east Kent and on the Isle of Wight. The lithostratigraphy and dinocyst records (137 taxa) of seven sections are presented, and the stratigraphic ranges of taxa are constrained relative to stage and zonal boundaries, located using extensive macrofossil data. Results are integrated with a previous complementary study of the Isle of Wight Santonian to test and refine existing dinocyst bioevent schemes. Sixteen dinocyst events are proposed as a sequence of biostratigraphic datum levels for the lower Coniacian to uppermost Santonian which, based on average sedimentation rates, represent an average temporal resolution of around 360 kyr. The event stratigraphy forms a basis for the first high-resolution correlation study of quantitative dinocyst data from the Upper Cretaceous of NW Europe. A new genus Culversphaera Prince, Jarvis, Pearce et Tocher gen. nov. is proposed with the new combination Culversphaera velata Prince, Jarvis, Pearce et Tocher gen. et comb. nov. Five new species: Ellipsodinium membraniferum Prince, Jarvis, Pearce et Tocher sp. nov., Senoniasphaera macroreticulata Prince, Jarvis, Pearce et Tocher sp. nov., Senoniasphaera whitenessii Prince, Jarvis, Pearce et Tocher sp. nov., Xenascus spinatus Prince, Jarvis, Pearce et Tocher sp. nov. and X. yunii sp. nov., and the new subspecies S. protrusa congrensa Prince, Jarvis, Pearce et Tocher subsp. nov. are described.     

Paralygodium meckertii sp. nov. (Schizaeaceae) from the Upper Cretaceous (Coniacian) of Vancouver Island, British Columbia, Canada

More than 50 specimens of permineralized fertile pinnules with abaxially borne sporangia have been discovered in calcareous marine nodules from the Upper Cretaceous (Coniacian) Comox Formation from the Eden Main localities on Vancouver Island, British Columbia, Canada. Isolated pinnules 1.6–3.0 mm wide × 1.6–2.8 mm long are lobed and abaxially enrolled to form irregular globose structures. Pyriform sporangia 216–300 μm wide × 360–468 μm long occur in two rows on the abaxial surface of pinnule lobes. Sporangia have an apical annulus of 15–18 cells. Spores are tetrahedral and trilete, 33–42 μm in diameter, with straight to concave interradial sides, laesurae extending nearly to the equator, and a psilate exine. Spores are assignable to the sporae dispersae genus Deltoidospora. Fertile pinnules are compared to fossils of Anemia poolensis and two previously described species of Paralygodium, and show closest similarities to P. vancouverensis from the Eocene of British Columbia. The Cretaceous Eden Main specimens differ in number of pinnule lobes and their morphology and are described as a new taxon: P. meckertii sp. nov. This discovery extends the Cretaceous geographic range of Paralygodium from Japan to North America and adds to our knowledge of the diversity of extinct schizaeaceous ferns.     

A new genus and species of deep-sea glass sponge (Porifera, Hexactinellida, Aulocalycidae) from the Indian Ocean

New hexactinellid sponges were collected from 2589 m depth on the Carlsberg Ridge in the Indian Ocean during deep-sea dredging. All fragments belong to a new genus and species, Indiellagen. n.ridgenensissp. n., a representative of the family Aulocalycidae described here. The peculiar features of this sponge, not described earlier for other Aulocalycidae, are: longitudinal strands present in several layers and epirhyses channelization.     

Integrating palynological and geochemical data in a new approach to palaeoecological studies: Upper Cretaceous of the Banterwick Barn Chalk borehole, Berkshire, UK

The dinoflagellate cyst record from an Upper Cretaceous (uppermost Cenomanian–upper Coniacian) Chalk core, drilled at Banterwick Barn, Berkshire, is described and statistically correlated with elemental and stable isotope bulk sediment geochemical data from the same core. Seventy-two dinocyst species and subspecies are recorded, and stable carbon and oxygen isotopic (δ¹³C, δ¹⁸O) trends are documented. Lithostratigraphy and chemostratigraphic correlation of the δ¹³C curve with an expanded section at Dover, Kent, are used to identify stratigraphically significant marls, and determine the positions of macrofossil zones and stage boundaries in the Banterwick Barn core. These data indicate that >30 m of chalk at Dover are represented by <2 m of Chalk Rock at Banterwick Barn, with much of the succession being absent due to erosion and non-deposition. First and last appearance datums (FAD, LAD), first and last common occurrences, and acmes of key Turonian–Coniacian dinocyst species are documented and compared with other records from the Anglo–Paris Basin. A new subspecies, Senoniasphaera rotundata alveolata is proposed, which has a FAD in the lower Turonian and last appears (LAD) in the lower Coniacian. Senoniasphaera rotundata rotundata [autonym, herein] has its FAD in the middle Turonian, first common occurrence in the uppermost Turonian, and LAD in the upper Coniacian. An extremely impoverished assemblage of dinocysts in the highest Cenomanian to lowest Turonian is considered to be largely a preservational artefact of intraclastic nodular and calcarenitic chalks, and is not related directly to the well-documented global oceanic anoxic event (OAE2) occurring at that time (93.5 Ma). A sharp increase in dinocyst abundance in the lower Turonian corresponds with a change in lithology to more marly chalks. A gradual decrease in the number of species is observed through the middle Turonian to upper Coniacian; δ¹⁸O records show that this was associated with global climatic cooling. Cluster analysis of the dinocyst abundance record with geochemical data indicates four distinct species groups with characteristic geochemical associations, i.e. Groups 1–4. Groups 1 and 2 are associated with phases of increased siliciclastic supply; a positive correlation with higher δ¹³C values differentiates the latter. Group 3 is independent of carbonate and detrital input, and Group 4 is associated with high carbonate flux and low detrital supply. These groupings suggest that cyst-forming dinoflagellates exhibited a range of ecological niches in the Late Cretaceous. Although the relationship between the encystment process and the geochemical associations is unclear, key environmental factors are likely to be sea-level and climate related, including water depth, turbidity, nutrient supply, sea-surface temperature, and environmental stability/predictability. Integrated geochemical and palynological studies have great potential for inter-regional correlation and palaeoenvironmental interpretation.     

Phylogeographical history of the sponge Crambe crambe (Porifera, Poecilosclerida): range expansion and recent invasion of the Macaronesian islands from the Mediterranean Sea

We studied sequence variation in the nuclear ribosomal internal transcribed spacers (ITS-1 and ITS-2) in 111 individuals from 11 populations/localities of the sponge Crambe crambe across the core species range in the western Mediterranean Sea and Atlantic Ocean. We report the first confirmed instance of intragenomic variation in sponges. Phylogeographical, nested clade and population genetic analyses were used to elucidate the species' evolutionary history. The study revealed highly structured populations affected by restricted gene flow and isolation-by-distance. A contiguous range expansion in the whole distribution area of the sponge was inferred. Phylogenetic analyses indicate a recent origin of most sequence types that could be explained by a recent origin of the species or a by recent bottleneck event in the studied area. A recent expansion of the distribution range to the Macaronesian region from the Mediterranean Sea was also detected, suggesting that C. crambe was recently introduced from the Mediterranean Sea to the Atlantic Ocean via human-mediated transport, and that the pattern observed is not the result of a natural biogeographical relationship between these zones.     

A new species of Halisaurus from the Late Cretaceous phosphates of Morocco, and the phylogenetical relationships of the Halisaurinae (Squamata: Mosasauridae)

A new species of the basal mosasaurid Halisaurus from the Late Cretaceous (Late Maastrichtian) of the Oulad Abdoun Phosphate Basin of Morocco is described on the basis of both cranial and postcranial remains. H. arambourgi sp. nov. is characterized by unique features of the nares, frontal, parietal, girdle and limb bones. A phylogenetical analysis supports the monophyletic status of Halisaurus ; H. platyspondylus (Maastrichtian, New Jersey), H. ortliebi (Maastrichtian, Belgium) and H. arambourgi form an unresolved polytomy. This study does not support the attribution of ' Halisaurus ' sternbergii (Santonian, Kansas) to Halisaurus nor to any known genus. A new genus, Eonatator , is proposed for the reception of this species, Eonatator sternbergii comb. nov. The new taxon Halisaurinae ( Halisaurus  +  Eonatator ) is the sister-group of more advanced mosasaurids (Natantia). Halisaurines are defined by the shape of the lateral premaxilla–maxilla suture; an oblique contact plane between the parietal and the supratemporal; a preaxial ridge present on the distal two-thirds of the radius length; and tibia and fibula long and slender with slightly expanded extremities.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 447–472.     

中国东北早白垩世一种新的昼蜓化石 (蜻蜓目: 昼蜓科)

本文记述昼蜓科化石一新属新种-孟氏丽昼蜓Abrohemeroscopus mengi gen.et sp.nov.。化石采自辽宁省义县早白垩世九佛堂组地层中。新属与巴依萨昼蜓Hemeroscopus Pritykina,1977在形态上比较相似,但在演化程度上更为原始,主要体现在下面几个方面：(1) 后翅臀套较小,仅有6～7个翅室; (2) 径增脉（Rspl）缺; (3) 后翅CuAa脉弯曲,带有5个明显的后分支; (4)前翅MP脉不显短,终止于翅后缘近翅结处; (5) 翅痣下有一个明显的支脉; (6) 后翅CuAa 和MP域基部较窄,在三角室下方仅有1排翅室。这是昼蜓科化石在中国的最老记录。     

A new egg with avian egg shape from the Upper Cretaceous of Zhejiang Province,China

A new egg is described from the Upper Cretaceous lacustrine deposit of the Chichengshan Formation in the Tiantai Basin, Zhejiang Province, southeast China. The new specimen shares eggshell micro-features with members of the oofamily Stalicoolithidae, Paraspheroolithus of the oofamily Spheroolithidae and Mosaicoolithus (oofamily indet.), with barrel-shaped cones, prolatocanaliculate pore system, horizontal accretion lines and light stripes throughout the eggshell. However, the new egg differs from the aforementioned ootaxa by its small size and asymmetrical shape, revealing new morphological variation among eggs with microstructure similar to that of Paraspheroolithus, Mosaicoolithus and Stalicoolithidae. We refer the new egg to a new oogenus and oospecies, thus increasing the diversity of the Tiantai Basin oofauna. The Tiantai Basin has yielded a variety of dinosaur eggs and one turtle clutch. Comparatively, the new egg is surprisingly small and ovoid, a morphology usually associated with avian eggs, although the absence of a squamatic layer excludes the egg from being referred to this group.     

Upper Campanian–Maastrichtian chronostratigraphy of the Skælskør‐1 core,Denmark: correlation at the basinal and global scale and implications for changes in sea‐surface temperatures

The lithostratigraphy, calcareous nannofossil biostratigraphy, carbon‐ and oxygen‐isotope stratigraphy and gamma‐ray profile are presented for the Skælskør‐1 core, eastern Denmark. The correlation of carbon isotopes to Gubbio (Italy) and ODP Site 762C (Indian Ocean) provides the chronostratigrahical framework of the core through a tie to magnetostratigraphy. Two new carbon‐isotope excursions are defined for the uppermost Maastrichtian of the core and prove useful for long‐distance correlation. Twenty stratigraphic tie‐points are used for correlation of the upper Campanian–Maastrichtian interval by combining carbon‐isotope and gamma‐ray variations. Significant dissimilarities in the gamma‐ray profiles of the Danish Basin cores preclude the sole use of this tool for basin‐scale correlations. Bulk oxygen‐isotopes and semi‐quantitative abundance changes in the warm‐water calcareous nannofossil Watznaueria barnesiae and the cool‐water Kamptnerius magnificus highlight the following past changes in sea‐surface temperatures (SSTs): relatively warm late Campanian SSTs, cooling across the Campanian–Maastrichtian boundary and through the early Maastrichtian, warming across the early–late Maastrichtian transition, cooling in the late Maastrichtian, intense warming in the latest Maastrichtian chron C29r, followed by a very short episode of cooling immediately before the Cretaceous–Palaeogene boundary. The late Campanian–Maastrichtian evolution in sea water temperatures inferred from the Danish Basin is similar to that delineated at tropical latitude oceanic sites.     

The mitogen-activated protein kinase p38 pathway is conserved in metazoans: cloning and activation of p38 of the SAPK2 subfamily from the sponge Suberites domuncula

Our recent data suggest that during auto- and allograft recognition in sponges (Porifera), cytokines are differentially expressed. Since the mitogen-activated protein kinase (MAPK) signal transduction modulates the synthesis and release of cytokines, we intended to identify one key molecule of this pathway. Therefore, a cDNA from the marine sponge Suberites domuncula encoding the MAPK was isolated and analyzed. Its encoded protein is 366 amino acids long (calculated Mr 42 209), has a TGY dual phosphorylation motif in protein kinase subdomain VIII and displays highest overall similarity to the mammalian p38 stress activated protein kinase (SAPK2), one subfamily of MAPKs. The sponge protein was therefore termed p38_SD. The overall homology (identity and similarity) between p38_SD and human p38alpha (CSBP2) kinase is 82%. One feature of the sponge kinase is the absence of threonine at position 106. In human p38alpha MAPK this residue is involved in the interaction with the specific pyridinyl-imidazole inhibitor; T106 is replaced in p38_SD by methionine. Inhibition studies with the respective inhibitor SB 203580 showed that it had no effect on the phosphorylation of the p38 substrate myelin basic protein. A stress responsive kinase Krs_SD similar to mammalian Ste20 kinases, upstream regulators of p38, had already previously been found in S. domuncula. The S. domuncula p38 MAPK is phosphorylated after treatment of the animal in hypertonic medium. In contrast, exposure of cells to hydrogen peroxide, heat shock and ultraviolet light does not cause any phosphorylation of p38. It is concluded that sponges, the oldest and most simple multicellular animals, utilize the conserved p38 MAPK signaling pathway, known to be involved in stress and immune (inflammatory) responses in higher animals.     

Embryos of therizinosauroid theropods from the Upper Cretaceous of China: diagnosis and analysis of ossification patterns

Exceptionally complete, in ovo dinosaur embryos from the Upper Cretaceous of China are analysed. Ossification patterns of these embryos suggest that they died during the final third of their development. The therizinosauroid identity of the embryos follows from: (1) an edentulous premaxilla with a sharp downturned edge; (2) dentary with a lateral shelf; (3) teeth with fan-shaped crowns, with a few marginal cusps; (4) humerus with a massive deltopectoral crest extending proximally, with a pointed proximomedial tuberosity; (5) ilium with an expanded and hooked preacetabular process; (6) strongly curved hypertrophied manual unguals tapering to sharp points. These embryos are closest to two Chinese therizinosauroids, Neimongosaurus yangi Zhang et al . 2001 and Erliansaurus bellamanus Xu et al . 2002 . An elongated narial opening, reduced basipterygoid process, low cervical neural spines, a transversely narrow pubic apron, and a pubic foot expanded anteriorly are found in these embryos and are synapomorphies uniting the Therizinosauroidea and the Oviraptorosauria. Fusion of cervical and caudal neural arches and centra, complete ossification of thoracic ribs and ilium, possible co-ossification of tibia and fibula, fused pubes, complete meta- and acropodial elements, together with small portions of unossified epiphyses of long bones suggest an advanced precociality of these embryos.     

New species of scarabaeoid beetles from the family Glaresidae (Coleoptera: Scarabaeoidea) from the Cretaceous of Transbaikalia

A new species from the family Glaresidae, Cretoglaresis ovalis, sp. nov., is described from the Lower Cretaceous site Baisa in Transbaikalia. Improved diagnosis of the genus Cretoglaresis Nikolajev, 2007 is given.     

A new Bennettitalean trunk with unilacunar five-trace nodal structure from the Upper Cretaceous of Hokkaido, Japan

A new species of Bucklandia is described based on a permineralized fossil trunk that was obtained from sediments of Upper Cretaceous age from Hokkaido, Japan. The quality of preservation is exquisite, and anatomical and morphological features are preserved at the cellular level. The specimen is clearly bennettitalean because of the cycadeoidean-type arrangement of vascular bundles in the petiole. However, this specimen is unique among previously described progymnosperms and gymnosperms in possessing a unilacunar five-trace type of nodal structure. The fossil thus contributes to a more complete understanding of the variation of nodal structure in bennettitalean trunks.     

A new species of Tingidae (Insecta: Hemiptera: Heteroptera) from the Lower Cretaceous of Transbaikalia

A new species of lace-bug Sinaldocader ponomarenkoi sp. nov. (Tingidae: Phatnomatini) is described from the Lower Cretaceous Transbaikalian locality Baissa. The new species differs from the type species S. drakei Popov, 1989 from the Lower Cretaceous of Mongolia in the well-developed lateral carinae of pronotal disc and in the details of hemelytral venation.     

Morphology of the endocranial cavities of Campinasuchus dinizi (Crocodyliformes: Baurusuchidae) from the Upper Cretaceous of Brazil

Two specimens of Campinasuchus dinizi (CPPLIP 1319 and CPPLIP 1360) belonging to Baurusuchidae (Crocodyliformes, Notosuchia) from the Upper Cretaceous Bauru Group of Minas Gerais state (Brazil) were scanned in a Toshiba Aquilion 64 CT machine. Based on these data, it was possible to identify and reconstruct the paranasal sinuses, the nasal cavity proper, the nasopharyngeal duct, the encephalon, the paratympanic sinuses, and the semicircular canals of the inner ear. The paranasal sinuses present similar morphology to those of other mesoeucrocodylians, especially eusuchians. The nasal cavity proper occupies the entire rostral region, with an expansion in the olfactory region. The expansion in the nasal cavity is present in other notosuchians and theropod dinosaurs (e.g., Tyrannosaurus rex Osborn, 1905), but less developed in aquatic crocodilians, which may indicate an olfactory acuity related to terrestrial habits. The encephalon is similar in shape to that of other mesoeucrocodylians. The rostral semicircular canal is smaller than the caudal one, differing from most mesoeucrocodylians. The paratympanic sinuses are more developed in C. dinizi than in eusuchians, being more similar to Tyrannosaurus rex. Campinasuchus dinizi presents few variations in the internal structures of the skull in relation to taxa with different ecological niches, probably indicating that ecological factors do not strongly influence the morphology of these structures.