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1.
Palynological studies realized from a borehole drilled on the site of ANDRA (Agence Nationale pour la gestion des Déchets RAdioactifs; Aube Centre near Soulaines, Paris Basin, France) show a sedimentary discontinuity between, on one hand, the Argiles à Plicatules (lower Aptian in age) and Argiles Ostréennes (Lower Barremian/Upper Barremian in age) and, on the other hand, between these same Argiles Ostréennes and the Calcaire à Spatangues (Lower Hauterivian). These conclusions argue against the chronostratigraphical subdivision recently proposed on the basis of sequence stratigraphical and sedimentological interpretations.  相似文献   

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3.
Two new isolated upper anterior premolars (p1–3) of multituberculates are described from the Barremian of Galve in Spain. One specimen is tricuspid and belongs toEobaatar hispanicus Hahn &Hahn, 1992. The other is the first tetracuspid p1–3 known from Galve. It is very similar to respective teeth of the Paulchoffatiidae G.Hahn, 1969 from the Upper Jurassic of Portugal. Therefore, this very small tooth belongs very probably to the paulchoffatiid taxonGalveodon nannothus Hahn &Hahn, 1992 which is also characterized by tiny dimensions  相似文献   

4.
The shell microstructure of the genus Monticlarella Wisniewska, 1932 is studied for the first time, with the species M. nova (Karakash, 1907) and M. lineolata (Phillips, 1835) from the Upper Hauterivian–Lower Barremian of Crimea being used as an example. It is shown that there is a strong similarity between the shell structure of this genus and another representative of the family Norellidae, Suiaella, thus supporting the possibility of using the shell microstructure as a diagnostic feature of the family Norellidae.  相似文献   

5.
《Palaeoworld》2016,25(1):76-83
Some typical components of the Jehol Biota, including conchostracans Eosestheria sp., the mayfly Ephemeropsis trisetalis Eichwald, 1864, the aquatic beetle Coptoclava longipoda Ping, 1928, and a fragmentary dragonfly, are reported for the first time from the Bayingebi Formation in the Celaomiao region, western Inner Mongolia, China. This discovery indicates that the middle Upper Member of Bayingebi Formation can be correlated with the upper Yixian and the lower Jiufotang formations in western Liaoning Province. Combining it with the radio-isotopic dating result, we further believed that the Upper Member of Bayingebi Formation could be roughly correlated with the Yixian, Jiufotang, and Shahai formations, and the overlying Suhongtu Formation with the Fuxin Formation in western Liaoning Province.In the major Bayingebi Basin, palaeontological and radio-isotopic dating evidence shows that the Bayingebi Formation has a long depositional history of over 30 Ma: its Upper Member bearing the Jehol Biota and the early Fuxin Biota is probably coeval to the Yixian, Jiufotang and Shahai formations and has a Barremian–early Albian age; its Lower Member may be Berriasian–Hauterivian in age and could be correlated with the upper Tuchengzi, Zhangjiakou, and Dabeigou formations in northern Hebei Province. This suggests that the Bayingebi Formation should be promoted to the stratigraphic rank of group and subdivided into several secondary units (formations). Unlike the previous result, the Yingen Formation is considered across the Lower Cretaceous–Upper Cretaceous boundary and being late Albian–early Turonian in age.  相似文献   

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7.
The fossil record of tyrannosauroid theropods is marked by a substantial temporal and morphological gap between small-bodied, Barremian taxa, and extremely large-bodied taxa from the latest Cretaceous. Here we describe a new tyrannosauroid, Xiongguanlong baimoensis n. gen. et sp., from the Aptian–Albian Xinminpu Group of western China that represents a phylogenetic, morphological, and temporal link between these disjunct portions of tyrannosauroid evolutionary history. Xiongguanlong is recovered in our phylogenetic analysis as the sister taxon to Tyrannosauridae plus Appalachiosaurus, and marks the appearance of several tyrannosaurid hallmark features, including a sharp parietal sagittal crest, a boxy basicranium, a quadratojugal with a flaring dorsal process and a flexed caudal edge, premaxillary teeth bearing a median lingual ridge, and an expanded axial neural spine surmounted by distinct processes at its corners. Xiongguanlong is characterized by a narrow and elongate muzzle resembling that of Alioramus. The slender, unornamented nasals of Xiongguanlong are inconsistent with recent hypotheses of correlated progression in tyrannosauroid feeding mechanics, and suggest more complex patterns of character evolution in the integration of feeding adaptations in tyrannosaurids. Body mass estimates for the full-grown holotype specimen of Xiongguanlong fall between those of Late Cretaceous tyrannosaurids and Barremian tyrannosauroids, suggesting that the trend of increasing body size observed in North American Late Cretaceous Tyrannosauridae may extend through the Cretaceous history of Tyrannosauroidea though further phylogenetic work is required to corroborate this.  相似文献   

8.
This work is mainly an answer to the work of Bert (2009), on families Helicancylidae Hyatt, 1894 and Acrioceratidae Vermeulen, 2009. On the nomenclatural speaking, the non validity of the genus Helicancylus Gabb, 1869 and of the family Helicancylidae Hyatt, 1894 and, consequently, the validity of the family Acrioceratidae Vermeulen, 2004 are established. The second part of this work is devoted to the respect of former work and, contrary to the assertions from Bert (2009), it is shown that the stratigraphical positioning of the Upper Barremian level with small Barremites, realized by Cotillon (1971), is at least as precise as that proposed by Bert. The last part of this work highlights a lack of bibliographical references, fact which had already been highlighted ( Vermeulen and Lepinay, 2010) in a former work of Bert et al. (2009).  相似文献   

9.
《Palaeoworld》2015,24(4):470-478
Two new species of flexible crinoids of the genus Cibolocrinus (Crinoidea, Flexibilia) from the Upper Carboniferous of the Moscow Region are described: C. kutasovi (Moscovian Stage, Podolskian Regional Substage) and C. gerassimovi (Gzhelian Stage, Dobryatinian Regional Substage). The first species, C. kutasovi, belongs to a group with low cone shaped cups that first appeared in the Moscow Basin and then spread to the Midcontinent of North America. In one specimen of C. gerassimovi the smallest infrabasal plate is situated in the A ray, which is not typical for flexible crinoids. A poorly preserved crown of Cibolocrinus sp. from the Upper Carboniferous (Gzhelian Stage) of the Darvaz Ridge (western Pamir, central Tajikistan) is also described. The described specimens of Cibolocrinus from the Moscow Region and the Darvaz Ridge are the first reliable specimens of this genus described from Europe and Asia.  相似文献   

10.
The most complete specimen of the plesiosaur genus Polycotylus from the Upper Cretaceous of the southern Urals is described. This specimen has much in common with the species P. latipinnis described from North America, but differs in the limb structure and cranial bones, so that it is assigned to a separate species, Polycotylus sopozkoi sp. nov.  相似文献   

11.
Upper Jurassic (Kimmeridgian–Tithonian) and Cretaceous (Berriasian–Barremian) strata of the Ukrainian part of the Carpathian Foredeep basement are rich, at least locally, in crinoid remains. Crinoids belonging to cyrtocrinids (Cyrtocrinida) are represented by whole cups, isolated remains of disarticulated cups, brachial plates and columnals. They are assigned to the following taxa: Cyrtocrinida indet., Eugeniacrinites cf. cariophilites (von Schlotheim), Lonchocrinus sp., Phyllocrinus stellaris Zaręczny, Ascidicrinus pentagonus (Jaekel), Gammarocrinites sp., Psalidocrinus armatus (Zittel), Psalidocrinus sp., and Hemibrachiocrinidae gen. indet. Cyrtocrinids are associated with other stalked (isocrinids, Isocrinida and millericrinids, Millericrinida) and stemless (saccocomids, Roveacrinida) crinoids. Columnals, pluricolumnals, brachial plates, and cirrals of isocrinids are assigned to Balanocrinus sp., Isocrinina fam. et subfam. indet., and columnals of millericrinids to Millericrinida indet. Free-living roveacrinids are assigned to Saccocoma sp. and Crassicoma sp. Knowledge on Jurassic and Cretaceous crinoids formerly described from Ukraine is discussed. Although majority of crinoids described herein seems to be allochthonous, autochthonous forms were also found with certainty in some intervals. These include some cyrtocrinids, which dominate in shallow-water environments of the Ukrainian Carpathian Foredeep basement. Isocrinids are also common in this shallow marine environment, whereas sessile saccocomids are assigned to low-energy, mud-supported bottom, open marine, outer-platform/upper slope, and relatively deep environments.  相似文献   

12.
A nearly complete specimen of a heteromorphic ammonite belonging to the genus Dissimilites Sarkar, 1954 (Ammonoidea, Ancyloceratina) has been collected in the Lower Barremian from south-east France. It is the first time that a such sample has been collected since the discovery by d'Orbigny in 1842 of the first specimens belonging of this taxon. Hypothetic until today, the existence of a spire in the first development of the shell is confirmed and a new diagnosis of the genus is given. Finally, the specific content of the genus is briefly analyzed as also its stratigraphical occurrence.  相似文献   

13.
Peter M. Galton 《Geobios》1980,13(3):451-457
The holotype of the nodosaurid ankylosaur Dracopelta zbyszewskii n. gen. and n. sp. is described from the Kimmeridgian(Upper Jurassic) of Ribomar on the west coast of Portugal. This is the first Upper Jurassic ankylosaur to be described that is represented by articulated bones. The specimen consists of a partial rib cage with thirteen dorsal vertebrae and five different types of dermal armor, two of wich show a partial overlap between adjacent plates.  相似文献   

14.

Background

The Yellow Cat Member of the Cedar Mountain Formation (Early Cretaceous, Barremian?) of Utah has yielded a rich dinosaur fauna, including the basal therizinosauroid theropod Falcarius utahensis at its base. Recent excavation uncovered a new possible therizinosauroid taxon from a higher stratigraphic level in the Cedar Mountain Formation than F. utahensis.

Methodology/Principal Findings

Here we describe a fragmentary skeleton of the new theropod and perform a phylogenetic analysis to determine its phylogenetic position. The skeleton includes fragments of vertebrae, a scapula, forelimb and hindlimb bones, and an ischium. It also includes several well-preserved manual unguals. Manual and pedal morphology show that the specimen is distinct from other theropods from the Cedar Mountain Formation and from previously described therizinosauroids. It is here named as the holotype of a new genus and species, Martharaptor greenriverensis. Phylogenetic analysis places M. greenriverensis within Therizinosauroidea as the sister taxon to Alxasaurus + Therizinosauridae, although support for this placement is weak.

Conclusions/Significance

The new specimen adds to the known dinosaurian fauna of the Yellow Cat Member of the Cedar Mountain Formation. If the phylogenetic placement is correct, it also adds to the known diversity of Therizinosauroidea.  相似文献   

15.
A new ankylosaurid (Ankylosauria: Dinosauria), Ziapelta sanjuanensis, gen. et sp. nov., is based on a complete skull, an incomplete first cervical half ring, a possible fragment of the second cervical half ring, and additional fragmentary osteoderms. The holotype specimen is from the Upper Cretaceous (Upper Campanian, Kirtlandian Land-Vertebrate Age) Kirtland Formation (De-na-zin Member) at Hunter Wash, San Juan Basin, in northwestern New Mexico, USA. Diagnostic characters of Ziapelta include: a large, prominent triangular median nasal caputegulum; a mixture of flat and bulbous frontonasal caputegulae; ventrolaterally oriented squamosal horns with a sharp, prominent dorsal keel; and the ventral surface of basicranium with three prominent anteroposteriorly oriented fossae. A phylogenetic analysis suggests that Ziapelta is not closely related to the other ankylosaurid from the De-na-zin Member, Nodocephalosaurus, but allies it to the northern North American ankylosaurids Ankylosaurus, Anodontosaurus, Euoplocephalus, Dyoplosaurus, and Scolosaurus.  相似文献   

16.
Heleroceratid ammonites are abundant in the Upper Barremiansediments of Zululand, South Africa, and representatives ofthe genera Heteroceras, Colchidites and Paraimerites are describedbelow. This assemblage shows strong similarities to faunas knownfrom the Caucasus region of the USSR, a similarity that persistedinto the succeeding Aptian. This similarity presents somethingof a paradox, because the genera concerned are among the leasthydrodynamically streamlined of ammonites. Their distributionsuggests an open marine connection between the Mediterraneanparts of Tethys and the eastern coast of Africa, linked, inthe Barremian — early Aptian at least, to Patagonia. Theirwide distribution also supports the view that climatic gradientswerelow during the Barremian and that the climate was generallywarmer than at present. (Received 12 January 1983;  相似文献   

17.
P. Lorenzo 《Geobios》1979,12(1):137-140
One specimen belonging to the arborescent lycopod stem species Lepidodendron dissitum SAUVEUR was found in connection with sporophylls named Lepidophyllum anthemis (KÖNIG) JONGMANS, species of a great stratigraphical and geographical range during the Upper Carboniferous, and specially abundant in the Spanish Stephanian. These two parts from the same plant are described and discussed in detail.  相似文献   

18.
A new styracosternan ornithopod genus and species is here described based on a partial postcranial skeleton and an associated dentary tooth of a single specimen from the Arcillas de Morella Formation (Early Cretaceous, late Barremian) at the Morella locality, (Castellón, Spain). Morelladon beltrani gen. et sp. nov. is diagnosed by eight autapomorphic features. The set of autapomorphies includes: very elongated and vertical neural spines of the dorsal vertebrae, midline keel on ventral surface of the second to fourth sacral vertebrae restricted to the anterior half of the centrum, a posterodorsally inclined medial ridge on the postacetabular process of the ilium that meets its dorsal margin and distal end of the straight ischial shaft laterally expanded, among others. Phylogenetic analyses reveal that the new Iberian form is more closely related to its synchronic and sympatric contemporary European taxa Iguanodon bernissartensis and Mantellisaurus atherfieldensis, known from Western Europe, than to other Early Cretaceous Iberian styracosternans (Delapparentia turolensis and Proa valdearinnoensis). The recognition of Morelladon beltrani gen. et sp. nov. indicates that the Iberian Peninsula was home to a highly diverse medium to large bodied styracosternan assemblage during the Early Cretaceous.  相似文献   

19.
Material of the hypsilophodontid dinosaur Valdosauruscanaliculatus (Ornithischia: Ornithopoda) is described from the Lower Cretaceous (Barremian) of southern England and a new species is recognized from the Lower Cretaceous (Aptian) of Niger, West Africa. This occurrence of Valdosaurus in Europe and Africa provides evidence of a land connection between these continents across Tethys sometime in the early Cretaceous.  相似文献   

20.
A specimen belonging to a new genus and species of fossil scorpion, Palaeoburmesebuthus grimaldii gen. n., sp. n., is described from the Upper Cretaceous amber of Myanmar (Burma). This is the first scorpion to have been found and described from Burmese amber (± 90 Myr). The new genus and species are unquestionable buthoid elements but they are assigned to an incertae familiae until further material may be available for study. To cite this article: W.R. Lourenço, C. R. Palevol 1 (2002) 97–101.  相似文献   

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