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Radiolaria from Cenomanian deposits of the Silesian Nappe near Sanok, Polish Carpathians

100%

Bak M.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1994

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tom 42

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nr 3

2

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Origin and significance of Late Cretaceous bioevents: Examples from the Cenomanian

84%

Wilmsen M.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

Palaeontological events, documented by widespread beds or thin intervals of strata with either unusual (“exotic”) or acmes of common faunal elements are a characteristic feature of Upper Cretaceous epicontinental shelf sediments in NW Europe. Their importance in stratigraphic calibration has early been recognized and these “bioevents” are widely used as correlation tools. Furthermore, it appears that there is a genetic link between sequence and event stratigraphy as most of the “classic” bioevents developed during specific intervals of a 3rd−order depositional sequence. Early transgressive bioevents (ETBs) are subdivided into two subtypes, i.e., the lag and migration subtype. The lag subtype corresponds to the transgressive surface and develops in response to winnowing and relative enrichment of robust biogenic hardparts. Taphonomic alteration and time−averaging are important features. The migration subtype is related to the disappearance of physical or ecological barriers that triggered faunal migrations. Despite their onlapping character, most ETBs are quasi−isochronous, and their preservation potential is usually high. Thus, they are very useful stratigraphic markers. Maximum flooding bioevents (MFBs) represent autochthonous biogenic concentrations with relatively low shell densities. They are related to habitat stability and ecospace expansion, and develop by population blooms of taxa well adapted to the special maximum flooding conditions of the wide epicontinental shelf of NW Europe (e.g., low food availability). Cenomanian MFBs of NW Europe are not time−averaged and may comprise stratigraphically more expanded intervals with gradational lower and upper boundaries. Their often wide palaeogeographic extent associated with very high chances of preservation results in an excellent inter−basinal correlation potential. Late highstand bioevents (LHBs) are local to regional shell concentrations deposited as a result of increasing winnowing of fines and reworking by storms, currents and waves during late highstands. LHBs usually consist of paucior even monospecific skeletal concentrations with a high degree of fragmentation. Simple shell beds related to a single (storm) event, and composite (multiple−event) shell beds are recognized. LHBs share some features of ETBs, but lack of time−averaging, are laterally restricted and have low preservation potential. Thus, their importance in interbasinal correlation is poor. The time scales of Cenomanian bioevents range through several orders of magnitude (hours–days in LHB storm event concentrations to ~100 kyr in MFBs). In terms of position within sequences, the three bioevent types correspond to shell concentrations recognized in Mesozoic–Cenozoic formations around the world. Shell beds with similar positions within cycles as well as comparable sedimentologic and taphonomic characteristics have also been described from high−frequency sequences and parasequences, suggesting that the formational processes of shell beds operate in base−level controlled sedimentary cycles of different hierarchies (i.e., 3rd−up to 7th−order).

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Ammonoid biodiversity changes across the Cenomanian-Turonian boundary in the Yezo Group, Hokkaido, Japan

84%

Kurihara K., Toshimitsu S., Hirano H.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 4

Ammonoid biodiversity changes from shallow to offshore environments across the Cenomanian–Turonian (C–T) boundary are reconstructed in the Yezo Group, Hokkaido, Japan. This group was probably deposited at approximately 35–45ºN along a westward subduction margin in the northeastern Asian continent. Temporal changes in species richness in the Yezo Group, which show persistently high values during the middle Cenomanian and then decline stepwise from near the middle–late Cenomanian boundary, resemble those in Europe, but not those in Tunisia and the Western Interior. These differences suggest that the Cenomanian–Turonian “mass extinction” was not a global event for ammonoids but was restricted to mid−palaeolatitudinal regions (Europe and Japan). Sea level and climate changes probably influenced ammonoid faunas in the Yezo Group as well as those in Europe. However, it is unlikely that a single, simple cause led to the C–T boundary “mass extinction” because various abiotic changes in the Cenomanian–Turonian transition have been detected, and biotic and abiotic change are interrelated.

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The oldest Brazilian snakes from the Cenomanian (early Late Cretaceous)

84%

Hsiou A. S., Albino A. M., Medeiros M. A., Santos R. A. B.

Acta Palaeontologica Polonica

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2014

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tom 59

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nr 3

South American Mesozoic snake diversity is mostly represented by genera from the Cenomanian (Najash), Santonian– Campanian (Dinilysia), and Campanian–Maastrichtian (Alamitophis, Patagoniophis, Rionegrophis, and Australophis) of Patagonia, Argentina. In this paper, we describe a new snake genus and species, Seismophis septentrionalis, from the Cenomanian (early Late Cretaceous) of the Alcântara Formation, Maranhão, northeastern Brazil. The new snake comprises a posteriormost trunk vertebra and possibly a poorly preserved midtrunk vertebra. Both vertebrae share small size, zygosphene moderately thick with a rectilinear roof, absence of paracotylar foramina, presence of parazygantral foramina, and strongly marked parasagittal ridges of the neural arch. The new snake is here considered of uncertain systematic affinities, but probably close to the limbed snake Najash rionegrina. Although the material is very fragmentary and the systematic assignment is still unresolved, this snake represents the oldest, as well as probably the most primitive snake from Brazil.

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First Cenomanian dinosaur from Central Europe [Czech Republic]

84%

Fejfar O., Kostak M., Kvacek J., Mazuch M., Moucka M.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 2

We describe the first dinosaur skeletal remains found in the Czech Republic, consisting of one complete femur and indeterminable bone fragments. They were recovered from the upper Cenomanian near−shore marine sediments deposited on the slopes of an ancient archipelago, several kilometres north of the larger Rhenish−Bohemian Island that was situated in what is now the middle of Europe. Sediments yielding dinosaur remains are of late Cenomanian age, Inoceramus pictus–I. pictus bohemicusinoceramid zone of the local lithostratigraphic unit, the Peruc−Korycany Formation. These are the first uncontested dinosaurian fossils reported from this formation and also the first Cenomanian dinosaur record in Central Europe. They document a small ornithopod belonging to an iguanodontid species comparable with similar Late Cretaceous European forms. The herbivorous dinosaur lived among a vegetation transitional between salt marsh flora, with abundant halophytic conifer Frenelopsis alata; and an alluvial plain assemblage dominated by lauroid angiosperms.

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Two bone fragments of ornithocheiroid pterosaurs from the Cenomanian of Volgograd region, Southern Russia

84%

Averianov A. O., Kurochkin E. N., Pervushov E. M., Ivanov A. V.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 2

Two pterosaur bone fragments, a distal humerus and a distal femur, from the upper Cenomanian of the Volgograd Region in the Don River basin of southern Russia are reported. Although fragmentary, these bones come from mature individuals and are exceptionally well and three−dimensionally preserved, allowing a detailed description of their anatomy. Both specimens can be referred to a middle−sized ornithocheiroid pterosaur with a reconstructed wingspan of about 4 m. The humerus shows affinities with Istiodactylus from the Barremian of England, whereas the femur fragment is not identifiable beyond Ornithocheiroidea indet.

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Brochocoleus zhiyuani, a new species of brochocolein beetle (Coleoptera: Ommatidae) from the Cretaceous amber of Myanmar

67%

Liu Z., Tan J., Slipinski A., Jarzembowski E. A., Wang B., Ren D., Pang H.

Annales Zoologici

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2017

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tom 67

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nr 1

A new species of the extinct genus Brochocoleus Hong, Brockocoleus zhiyuani sp. nov. is described based on two well preserved fossils embedded in the mid-Cretaceous amber originating from Myanmar. The species is deposit to B. caseyi Jarzembowski, Wang et Zheng, 2016 described from the same deposits but differs in having not an elongated head, long antennae and rounded prothorax.

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The early angiosperm Pseudoasterophyllites cretaceus from Albian-Cenomanian of Czech Republic and France revisited

67%

Kvacek J., Gomez B., Zetter R.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 2

The early halophytic angiosperm Pseudoasterophyllites cretaceus from the Cenomanian Peruc Korycany Formation of the Bohemian Cretaceous Basin and from the Late Albian of the Northern Aquitanian Basin is redescribed. The plant is characterized by semi−whorled linear, and heavily cutinized leaves with paracytic stomata. Stamens associated with P. cretaceus possess an apically emerging connective that possesses the same epidermal cell pattern as the leaves. The stamens are massive, tetrasporangiate, and contain Tucanopollis pollen, thus clearly indicating affinities of P. cretaceus to the basal angiosperms. The plants that co−occur with P. cretaceus in semi−autochtonous taphocoenoses include the conifer Frenelopsis alata, which was likely a halophyte or halo−tolerant glycophyte growing in habitats close to the sea.

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Vertebral morphology, dentition, age, growth, and ecology of the large lamniform shark Cardabiodon ricki

67%

Newbrey M. G., Siversson M., Cook T. D., Fotheringham A. M., Sanchez R. L.

Acta Palaeontologica Polonica

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2015

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tom 60

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nr 4

Cardabiodon ricki and Cardabiodon venator were large lamniform sharks with a patchy but global distribution in the Cenomanian and Turonian. Their teeth are generally rare and skeletal elements are less common. The centra of Cardabiodon ricki can be distinguished from those of other lamniforms by their unique combination of characteristics: medium length, round articulating outline with a very thick corpus calcareum, a corpus calcareum with a laterally flat rim, robust radial lamellae, thick radial lamellae that occur in low density, concentric lamellae absent, small circular or subovate pores concentrated next to each corpus calcareum, and papillose circular ridges on the surface of the corpus calcareum. The large diameter and robustness of the centra of two examined specimens suggest that Cardabiodon was large, had a rigid vertebral column, and was a fast swimmer. The sectioned corpora calcarea show both individuals deposited 13 bands (assumed to represent annual increments) after the birth ring. The identification of the birth ring is supported in the holotype of Cardabiodon ricki as the back-calculated tooth size at age 0 is nearly equal to the size of the smallest known isolated tooth of this species. The birth ring size (5-6.6 mm radial distance [RD]) overlaps with that of Archaeolamna kopingensis (5.4 mm RD) and the range of variation of Cretoxyrhina mantelli (6-11.6 mm RD) from the Smoky Hill Chalk, Niobrara Formation. The revised, reconstructed lower jaw dentition of the holotype of Cardabiodon ricki contains four anterior and 12 lateroposterior files. Total body length is estimated at 5.5 m based on 746 mm lower jaw bite circumference reconstructed from associated teeth of the holotype.

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Aalenian to Cenomanian terrestrial palynofloras of SW Scania, Sweden

67%

Vajda V.

Acta Palaeontologica Polonica

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2001

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tom 46

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nr 3

I describe dispersed miospore assemblages recovered from 35 drill-core samples from Höllviken 2, Norrevång 1, and Svedala 1 wells, all in SW Scania, Sweden. Over eighty taxa of pollen and spores, ranging from the Aalenian to the Cenomanian were identified. Four pollen/spore zones have been defined on the basis of key taxa and on the variation in the frequency of miospore groups. The palynofacies analysis indicates that a continental depositional environment prevailed during the Aalenian in Scania. A stratigraphic hiatus existed from the Aalenian then on until the Valanginian, when the depositional environment subsequently became marine. The marine conditions continued until the Cenomanian. A gradual increase in marine palynomorphs is found in the Cenomanian succession, indicating a transgression. On the basis of the palynoflora it is suggested that the vegetation consisted of cycads, conifers, pteridophytes and a very limited number of angiosperms.

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New sharks and rays from the Cenomanian and Turonian of Charentes, France

59%

Vullo R., Cappetta H., Neraudeau D.

Acta Palaeontologica Polonica

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2007

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tom 52

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nr 1

New or so far poorly known neoselachians from the Cenomanian and Turonian of SW France are described. The material studied herein comes from nine localities in the Charentes region, comprising palaeoenvironments ranging from coastal to open marine environments, and consists of two orectolobiforms, six lamniforms, and four rajiforms. The new taxa are Squalicorax coquandi sp. nov. and Roulletia bureaui gen. et sp. nov. within lamniforms, and Hamrabatis bernardezi sp. nov., Archingeayia sistaci gen. et sp. nov., and Engolismaia couillardi gen. et sp. nov. within rajiforms. New specimens of Odontaspis rochebrunei Sauvage, 1880 from the type area allow redescription of this taxon, assigned herein to the genus Cenocarcharias. Occurrences of Squalicorax baharijensis, S. cf. intermedius, and Archaeolamna sp., previously unrecorded from this region, and Almascyllium, a genus generally described from younger strata, are also noted, and improve knowledge of mid−Cretaceous selachian faunas from Western Europe.

Ograniczanie wyników

Radiolaria from Cenomanian deposits of the Silesian Nappe near Sanok, Polish Carpathians

Origin and significance of Late Cretaceous bioevents: Examples from the Cenomanian

Ammonoid biodiversity changes across the Cenomanian-Turonian boundary in the Yezo Group, Hokkaido, Japan

The oldest Brazilian snakes from the Cenomanian (early Late Cretaceous)

First Cenomanian dinosaur from Central Europe [Czech Republic]

Two bone fragments of ornithocheiroid pterosaurs from the Cenomanian of Volgograd region, Southern Russia

Brochocoleus zhiyuani, a new species of brochocolein beetle (Coleoptera: Ommatidae) from the Cretaceous amber of Myanmar

The early angiosperm Pseudoasterophyllites cretaceus from Albian-Cenomanian of Czech Republic and France revisited

Vertebral morphology, dentition, age, growth, and ecology of the large lamniform shark Cardabiodon ricki

Aalenian to Cenomanian terrestrial palynofloras of SW Scania, Sweden

New sharks and rays from the Cenomanian and Turonian of Charentes, France