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1.
A second hadrosauroid dinosaur from the early Late Cretaceous of Zuoyun,Shanxi Province,China 总被引:1,自引:0,他引:1
A second basal hadrosauroid dinosaur, Zuoyunlong huangi gen. et sp. nov., is reported from the early Late Cretaceous Zhumapu Formation in Zuoyun County, Shanxi Province, northern China. Zuoyunlong preserves a partial right ilium and ischium and is unique in having a very short postacetabular process 50% as long as the iliac central plate. Our cladistic analysis recovers Zuoyunlong as the most basal Late Cretaceous hadrosauroid, with a sister taxon relationship with Probactrosaurus from the late Early Cretaceous of Inner Mongolia. Including Zuoyunlong, four Cenomanian basal hadrosauroids have been recorded, and the two taxa in North America (Eolambia and Protohadros) represent the earliest known hadrosauroids outside of Asia. In the light of the proposed phylogenetic topology and biogeographic data, the discovery of Zuoyunlong indicates that the first dispersal of hadrosauroids from Asia to North America probably happened around the boundary between the Early and Late Cretaceous. 相似文献
2.
Herrerasauridae comprises a basal clade of dinosaurs best known from the Upper Triassic of Argentina and Brazil, which have yielded remains of Herrerasaurus ischigualastensis and Staurikosaurus pricei, respectively. Systematic opinion regarding the position of Herrerasauridae at the base of Dinosauria has varied. Here we describe a new herrerasaurid, Sanjuansaurus gordilloi gen. n., sp. n., based on a partial skeleton from Carnian-age strata of the the Upper Triassic Ischigualasto Formation of northwestern Argentina. The new taxon is diagnosed by numerous features, including long, band-shaped and posterolaterally oriented transverse process on the posterior cervical vertebrae; neural spines of the sixth to eighth dorsal vertebrae, at least, bearing acute anterior and posterior processes; scapula and coracoid with everted lateral margins of the glenoid; and short pubis (63% of the femoral length). Phylogenetic analysis placed Sanjuansaurus within a monophyletic Herrerasauridae, at the base of Theropoda and including Herrerasaurus and Staurikosaurus. The presence of Sanjuansaurus at the base of the Ischigualasto Formation, along with other dinosaurs such as Herrerasaurus, Eoraptor, Panphagia, and Chromogisaurus suggests that saurischian dinosaurs in southwestern Pangea were already widely diversified by the late Carnian rather than increasing in diversity across the Carnian-Norian boundary. 相似文献
3.
On the finding of ornithomimid dinosaurs (Saurischia, Ornithomimosauria) in the Upper Cretaceous beds of Tajikistan 总被引:1,自引:0,他引:1
Fragmentary remains of ornithomimids (Ornithomimidae indet.) from the Lower Santonian (Upper Cretaceous) Kansai locality in northwestern Fergana (Tajikistan) are described, and the composition of its dinosaurian assemblage is updated. 相似文献
4.
D. V. Grigor’ev A. O. Averianov M. S. Arkhangelsky E. M. Pervushov N. Yu. Zozyrev 《Paleontological Journal》2009,43(3):311-317
The premaxilla of a mosasauroid lizard from the Lysaya Gora 3 locality in Saratov (Upper Cretaceous, Cenomanian) is described. To date, the oldest known mosasaur remains have been dated Turonian. The premaxilla is most similar in morphology to that of Russellosaurus from the Turonian of the United States; however, the absence of sufficient diagnostic characters only allows its attribution to Mosasauridae indet. 相似文献
5.
Summary Sedimentological, paleontological and sequence analyses of Cenomanian limestones in Sicily reveal the facies architecture
and dynamics of a Mid Cretaceous rudistdominated platform margin from Western Tethys. The studied deposits outcrop near Palermo,
as part of a large structural unit of the Sicilian Maghrebids. They belong to the Panormide carbonate platform, a Mesocenozoic
paleogeographic domain of the African margin.
The lateral continuity of the beds along three nearly parallel E-W outcrop sections allowed the recording of cm/dm thick lithological
and faunal variations. Nine main lithofacies associations have been recognised along about 200 m of subvertical strata. Their
vertical and lateral organisation points to a transition from highenergy shelf-margin rudist patches and shoals to more internal
lagoonal-tidal environments over a short distance.
The lithofacies evolution and stacking pattern along the three sections made it possible to define elementary cycles, composite
cycles and larger-scale sequences with a dominant shallowing-upward trend. Their hierarchical organisation implies that sea-level
fluctuations were an important factor in their formation.
The cycles are characterised by a great variation in facies as a result of transgressive-regressive events in different sectors
of the inferred Cenomanian shelf. Subtidal cycles typical of the shelf margin (4–10 m-thick) are particularly well identifiable.
They are made of large Caprinidae and Sauvagesiac rudstone-to-floatstone (about 2/3 of the total thickness), capped by rudist-conglomerates,
often organised into 3–5 fining-upward amalgamated beds and showing, in places, effects of surface-related diagenesis. In
more internal shelf areas the cycles consist of Caprinidae-Radiolitidae floastone grading up into amalgamated beds of angular
bioclastic rudstone/grainstone. Alternations of foraminifer/ostracod mudstone/wackestone and bioclastic grainstone/fine-rudstone,
capped by loferites and/or by other emersion-related overprintings, characterise the cycles formed in the peritidal zones.
these cycles are stacked into three incomplete depositional sequences. The sequence boundaries have been identified by the
abrupt interposition of peritidal cycles in subtidal rudist-rich cycles, with evidence of brief subaerial exposure. 相似文献
6.
Howard J. Falcon-Lang 《Palaeontology》2004,47(2):349-366
A new genus of ginkgoalean woody branch, Pecínovicladus kvaceki gen. et sp. nov., is described from the Upper Cretaceous (mid to late Cenomanian) Peruc-Korycany Formation at Pecínov Quarry, near Prague, Czech Republic. Eighteen branch specimens, anatomically preserved as charcoal, the product of wildfire, occur as allochthonous assemblages in intertidal facies and as parauthochthonous assemblages in supratidal salt marsh facies. Primary branches range from 7–13 mm in diameter, and are composed of a central, parenchymatous pith, a medial pycnoxylic xylem layer, and an outer periderm layer. Closely spaced, helically arranged leaf bases and rare secondary branch scars characterize the exterior. The branches are confidently referred to the Ginkgoales on the basis of a variety of diagnostic xylem features, most notably the presence of inflated axial parenchyma containing moulds of crystals, and by the precise anatomical correspondence of the leaf bases to those of detached, but facies-associated Nehvizdya obtusa leaves of known ginkgoalean affinity. The newly described ginkgoalean, together with cheirolepidiaceous conifers, formed fire-prone vegetation in halophytic salt marsh environments under a seasonal, subtropical climate. 相似文献
7.
A new generic name, Friisicarpus N. Maslova et Herman, is proposed to replace Platanocarpus Friis, Crane, et Pedersen, 1988. Pistillate capitate inflorescences of Friisicarpus nom. nov. are reported from the Cenomanian of western Siberia for the first time. They are found in association with leaves of the typical Platanus-morphotype. Earlier, remains belonging to this genus were found to be associated with pinnatifid leaves of cf. Sapindopsis variabilis Fontaine (Crane et al., 1993). 相似文献
8.
Summary A benthic community of sessile metazoans dominated by coralline sponges (e.g.Acanthochaetetes andVaceletia) is found within a Cenomanian-Turonian deep water hardground succession cropping out at the coastal area of the Bay of Biscay
near Santander. The characteristic K-strategic community exhibits a very close taxonomic relationship with modern communities
from the Pacific realm, which allows for a comparison with Recent environmental conditions. The sponge community was associated
with automicrites, microbialites, and thin mineralized limonitic biofilms. This biofacies is typically found in cryptic niches
of reefal buildups (“telescoping”). The iron-rich biofilms had a strong electrochemical corrosive ability which explains the
distinct submarine dissolution patterns. The hardground conditions are controlled, in part, by strong contour current regimes
linked with extremely oligotrophic water masses. This system was established during the drowning of a distal carbonate ramp
during the early Middle Cenomanian (A.rhotomagenese zone). In the uppermost portion of the hardground (Late Cenomaian, upperR. cushmani zone) the coralline sponge community was replaced by thick limonitic stromatolites with numerous encrusting foraminifera
(Miniacina-type) and by colonies of the problematic iron bacteriumFrutexites. This event is accompanied by an increase of terrigenous influx and detrital glauconite, indicating a fundamental change
in food web, and terminates the sponge dominated basal hardground interval. Thehardground was buried by hemipelagic sediments
during the Middle Turonian (upperR. kallesi zone).
Dedicated to the memory of Prof. Dr. JostWiedmann 相似文献
9.
V. R. Alifanov 《Paleontological Journal》2008,42(6):621-633
A new horned dinosaur, Gobiceratops minutus gen. et sp. nov. (Bagaceratopidae, Neoceratopsia), from the Upper Cretaceous Baruungoyot Formation of the Khermin Tsav locality (southern Mongolia) is described based on a 3.5-cm-long skull. The nasal included in the orbital border suggests relationship between the new taxon and Bagaceratops rozdestvenskyi. It is proposed that, unlike other neoceratopsian families, the family Bagaceratopidae is of Paleoasiatic origin. 相似文献
10.
The fossil record of planktonic foraminifera is a key source of data on the evolution of marine plankton. One of the most distinctive groups of Cretaceous foraminifera, the rotaliporids, widely used as a stratigraphic index, has always been considered to be a monophyletic clade. New data on the coiling direction and persistent morphological features of the late rotaliporids from the Upper Cenomanian of the Western Interior Seaway, USA, and the Vocontian Basin of southeast France is used as a phylogenetic proxy. Dealing with key morphological features, the coiling pattern of these keeled morphotypes proves that the rotaliporids group is polyphyletic and composed of Thalmanninella, that displays a dextral-coiling preference, and Rotalipora s.s., that have a proportionate-coiling mode. The stratigraphically youngest rotaliporids with keels co-occur with globular forms; and all morphologies transitional between these morphotypes are observed. The ontogenetic relationships between them are investigated, indicating that loss of the keel was a selective advantage that enabled those rotaliporids to remain in the surface water, thereby avoiding the expansion of the oxygen minimum zone. Two species are observed: Thalmanninella multiloculata and Rotalipora planoconvexa. These species are interpreted as having arisen by neoteny from Thalmanninella greenhornensis and Rotalipora cushmani respectively. 相似文献
11.
Scott D. Sampson Eric K. Lund Mark A. Loewen Andrew A. Farke Katherine E. Clayton 《Proceedings. Biological sciences / The Royal Society》2013,280(1766)
The fossil record of centrosaurine ceratopsids is largely restricted to the northern region of western North America (Alberta, Montana and Alaska). Exceptions consist of single taxa from Utah (Diabloceratops) and China (Sinoceratops), plus otherwise fragmentary remains from the southern Western Interior of North America. Here, we describe a remarkable new taxon, Nasutoceratops titusi n. gen. et sp., from the late Campanian Kaiparowits Formation of Utah, represented by multiple specimens, including a nearly complete skull and partial postcranial skeleton. Autapomorphies include an enlarged narial region, pneumatic nasal ornamentation, abbreviated snout and elongate, rostrolaterally directed supraorbital horncores. The subrectangular parietosquamosal frill is relatively unadorned and broadest in the mid-region. A phylogenetic analysis indicates that Nasutoceratops is the sister taxon to Avaceratops, and that a previously unknown subclade of centrosaurines branched off early in the group''s history and persisted for several million years during the late Campanian. As the first well-represented southern centrosaurine comparable in age to the bulk of northern forms, Nasutoceratops provides strong support for the provincialism hypothesis, which posits that Laramidia—the western landmass formed by inundation of the central region of North America by the Western Interior Seaway—hosted at least two coeval dinosaur communities for over a million years of late Campanian time. 相似文献
12.
Peter M. Galton 《Pal?ontologische Zeitschrift》1973,47(3-4):229-255
Palaeosaurus (?) diagnosticus Huene from the Stubensandstone (Upper Triassic, Norian) of Nordwürttemberg, Germany is made the type species of a new genus of prosauropod dinosaurEfraasia, which is referred to the family Anchisauridae. The anatomy ofEfraasia diagnostica is conservative and it was an ideal ancestor for the later and more specializedAnchisaurus polyzelus of North America. The slenderness of the manus and pes ofEfraasia andAnchisaurus is matched amongst prosauropods only by the feet ofGyposaurus capensis andThecodontosaurus antiquus. Staurikosaurus pricei Colbert from the Upper Triassic of Brazil is probably a very primitive theropod dinosaur. 相似文献
13.
The holotype of Paranthodon africanus (Broom) from the Kirkwood Formation (Lower Cretaceous) of the Algoa Basin, Cape Province, South Africa consists of a partial skull, the bones of which are very similar to those of Stegosaurus. Both sides of the maxillary tooth crowns have a bulbous cingulum and a very prominent central vertical ridge above the large apical denticle that is bordered anteriorly and posteriorly by four to seven smaller denticles. Diagnostically stegosaurian material is also known from the Lower Cretaceous of England (Craterosaurus) and China (Wuerhosaurus) and the Upper Cretaceous of India (Dravidosaurus). 相似文献
14.
Peter J. Makovicky Daqing Li Ke-Qin Gao Matthew Lewin Gregory M. Erickson Mark A. Norell 《Proceedings. Biological sciences / The Royal Society》2010,277(1679):191-198
Ornithomimosaurs (ostrich-mimic dinosaurs) are a common element of some Cretaceous dinosaur assemblages of Asia and North America. Here, we describe a new species of ornithomimosaur, Beishanlong grandis, from an associated, partial postcranial skeleton from the Aptian-Albian Xinminpu Group of northern Gansu, China. Beishanlong is similar to another Aptian-Albian ornithomimosaur, Harpymimus, with which it shares a phylogenetic position as more derived than the Barremian Shenzhousaurus and as sister to a Late Cretaceous clade composed of Garudimimus and the Ornithomimidae. Beishanlong is one of the largest definitive ornithomimosaurs yet described, though histological analysis shows that the holotype individual was still growing at its death. Together with the co-eval and sympatric therizinosaur Suzhousaurus and the oviraptorosaur Gigantraptor, Beishanlong provides evidence for the parallel evolution of gigantism in separate lineages of beaked and possibly herbivorous coelurosaurs within a short time span in Central Asia. 相似文献
15.
Occurrences of the Upper Cenomanian (Upper Cretaceous) belemnite Praeactinocamax plenus from the plenus Bed of northwest Germany (Söhlde-Loges working quarry near Salzgitter, Lower Saxony) are documented and described for the first time on the basis of two in situ finds. The find horizon and its surrounding beds are re-evaluated in a sequence stratigraphical context. In contrast to the interpretations of other authors, the plenus Bed is seen as a pelagization event in a parasequence of transgressively stacked beds, delimited by two significant erosion surfaces below and above. The exclusive occurrence of P. plenus in the top part of the plenus Bed and its absence from the post-plenus Bed succession, in the equivalent of which (higher part of the Plenus Marls Member) it is very common in southern England (Anglo-Paris Basin), is explained by ecological factors in stratigraphically complete sections (intra-shelf depressions) and by gaps in the stratigraphic records in swell settings. The distribution pattern of P. plenus suggests a preference for nearshore settings and a demersal mode of life. 相似文献
16.
Tvrtko Korbar Ladislav Fuček Antun Husinec Igor Vlahović Nenad Oštrić Dubravko Matičec Vladimir Jelaska 《Facies》2001,45(1):39-58
Summary The island of Cres is located in the northern part of the Adriatic Sea. The island is built up of predominantly Cretaceous
carbonates deposited in north-western part of extensive and long-lasting Adriatic Carbonate Platform. Owing to the influence
of synsedimentary tectonics supported by eustatic changes during the latest Albian/Early Cenomanian, different sedimentary
environments were established: from shallow intraplatform basin and related slope, across basin margin to protected shallow-platform.
During the Early to Middle Cenomanian rudist communities (ichthyosarcolitid/caprinid/radiolitid)flourished along a relatively
high-energy intraplatform basin margin. Fair amounts of coarse-grained bioclasts, derived almost exclusively from broken rudist
shells, were deposited over a marginal depocenter. Contemporaneously, pithonellid wackestone-packstones containing microbioclasts
and planktonic foraminifera were deposited basinward while marginal bioclastic sediments and limestone blocks of the basin
margin origin were sporadically deposited within the basin. The opening of the Cres intraplatform basin was aborted and the
basin was finally filled up during the Late Cenomanian. Since the Cres intraplatform basin was established at the beginning
of the Cenomanian it probably represented the initiation phase in the north-western extension of the later Adriatic Trough
development. 相似文献
17.
18.
Natalia Zavialova 《Grana》2018,57(5):325-344
The partially reticulate sculpture of Molaspora aspera sp. nov., a marsileaceous megaspore from a Cenomanian deposit in western France, distinguishes it from other species of Molaspora. An acrolamella entirely surrounds and obscures a small tetrad scar, a feature that has been demonstrated hitherto within members of the genus only in M. fibrosa. It was also encountered for the first time in M. lobata, with which the new species is associated in the same French mesofossil assemblage. The ultrastructure of the sporoderm of M. aspera is similar to that of M. lobata, but differs particularly in that the inner epispore is markedly thicker and may also contain numerous large, homogeneous spherules or, alternatively, holes of comparable dimensions and only a few small spherules. It is possible that these are a response to some hostile bacterial or other activity when the developing sporoderm was partially permeable. The cavity replacing part of the epispore in one of the specimens, and in the specimen of M. lobata examined, may be a preservational feature or have served to increase buoyancy of the spore in water. Molaspora lobata is very similar to megaspores of fossil and extant Regnellidium, but M. aspera bears some resemblance to other members of extant Marsileaceae and certain species of Cretaceous Arcellites, although there are significant differences between them. This suggests that Molaspora is a heterogeneous taxon embracing megaspores produced by water ferns of more than one natural genus, of which only Regnellidium has survived to the present day. 相似文献
19.
Cenomanian-Turonian ostracodes are reported from the western Colorado Plateau (Western Interior Basin) in the United States. Fifteen genera and twenty species are illustrated, six of which are new: Cytheromorphaperornata nov. sp., Looneyellaleckiei nov. sp., Asciocythereposterangulata nov. sp., Asciocytherearizonensis nov. sp., Cytheropteronclavifragilis nov. sp. and Hourcqiadakotaensis nov. sp. Three ostracode interval zones are proposed that broadly correspond to the existing late Cenomanian through to Middle Turonian Ammonite-zones of Kauffman et al. (1993). Paleoenvironments range from estuarine to coastal plain. 相似文献
20.
Samira Mendir Sihem Salmi-Laouar Gamal M. El Qot Wagih Ayoub-Hannaa Bruno Ferré 《Annales de Paléontologie》2021,107(2):102471
In the eastern Saharan Atlas, particularly in the northern area of Tebessa Province (NE Algeria), the widely outcropping Cenomanian strata display a highly diversified macrofauna, among which bivalves are prominently represented. Twenty-eight bivalve species are here reported for the first time from the Cenomanian of Hameimat Massifs. Based on the stratigraphic distribution of these bivalves, five bivalve zones were recognized, i.e., Costagyra olisiponensis - Gyrostrea delettrei, Rhynchostreon suborbiculatum - Exogyra conica, Ceratostreon flabellatum, Ilymatogyra africana, and Pycnodonte vesicularis vesiculosa - Rastellum carinatum zones. Correlation to the ammonite biozones of the same region as follows: the Costagyra olisiponensis - Gyrostrea delettrei and the Rhynchostreon suborbiculatum - Exogyra conica zones occur respectively in the Sharpeiceras schlueteri and Mantelliceras saxbii subzones of the lower Cenomanian Mantelliceras mantelli Zone. The Ceratostreon flabellatum Zone is correlated with the middle Cenomanian Acanthoceras rhotomagense Zone. The Ilymatogyra africana Zone is correlated with the upper Cenomanian Calycoceras naviculare and the Metoicoceras geslinianum zones. Finally, the Pycnodonte vesicularis vesiculosa - Rastellum carinatum Zone represents the uppermost Cenomanian. Detailed analysis of biometrical and morphological features of these bivalve specimens provides the most reliable tool within the scope of palaeo-environmental reconstitution and the many palaeo-ecological variables that had driven the development and distribution of these macro-invertebrates. Comparison of these new data to those of adjacent south Tethyian areas supports the homogeneity of the Cenomanian bivalve faunas. Such an affinity underlines more vividly the favorable marine communications and currents driving the geographic dispersal of these bivalves during the Cenomanian. 相似文献