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1.
Yan Zheng  Jun Chen 《Palaeoworld》2018,27(3):374-381
Chifengilyda robusta, a new extinct sawfly genus and new species assigned to Xyelidae, is described and figured here based on one fossil specimen from the Lower Cretaceous Yixian Formation of Ningcheng in Inner Mongolia, China. Chifengilyda robusta n. gen. n. sp. differs from other xyelydids in having a forewing with pterostigma completely sclerotized, Sc closer to C, Sc1 about 3 times as long as Sc2, Sc1 intersecting C far beyond Rs base, 2r-m postfurcal and cell 1mcu relatively large. This new taxon further enriches the diversity of Xyelydidae in the Early Cretaceous, and even enhances our understanding of the evolution and inter-genera and interspecies relationships of this family.  相似文献   

2.
《Palaeoworld》2020,29(3):534-543
Well preserved cyclocrinitids (calcareous green algae) are reported from early Palaeozoic deposits of Spiti, Himachal Pradesh, India. Casts of the algal fossils are preserved in calcareous grey siltstone unit of the Takche Formation (Late Ordovician–Early Silurian) which appears rusty/earthy brown due to weathering. The assemblage includes Cyclocrinites favus, Cyclocrinites pyriformis, Cyclocrinites cf. welleri, Cyclocrinites sp. and Cyclocrinites globosus. Both Cyclocrinites cf. welleri and Cyclocrinites globosus are reported for the first time from the entire Tethyan Himalaya, India. The described algal flora basically denotes relatively shallow marine depositional setting and low to moderate hydrodynamic conditions.  相似文献   

3.
The heteromorph ammonites of the family Bochianitidae from the Lower Cretaceous of the Crimean Mountains are revised. The validity of the genus Janenschites, separated from the genus Bochianites is confirmed. The species Bochianites neocomiensis (d’Orbigny), B. goubechensis Mandov, B. levis sp. nov. and B. crymensis sp. nov. are described from the Berriasian and the species Janenschites oosteri (Sarasin et Schöndelmayer) and J. incisus sp. nov. are described from the Lower Barremian. The family Bochianitidae first appeared at the beginning of the Berriasian in the southern regions (Africa and the Crimea), and spread to the northern regions of western Europe in the Valanginian-Hauterivian.  相似文献   

4.
Non-marine diatoms occur in the Deccan Intertrappean beds (Upper Cretaceous) of Mohgaon-Kalan, Chhindwara District, Madhya Pradesh and Pisdura, Lameta Formation (Upper Cretaceous), Maharashtra, India. This represents the oldest record of non-marine diatoms yet reported and the oldest from the Indian subcontinent. The diatoms were recovered from thin sections of chert and dinosaur coprolites by random fracturing. Solitary forms are the most common but colonial filaments up to five cells were also observed. Based on the morphological characters, the diatoms are identified as Aulacoseira Thwaites. The Lower Cretaceous marine diatom genus Archepyrgus Gersonde and Harwood also resembles Aulacoseira in general morphological characters and it seems that Aulacoseira evolved from Archepyrgus and migrated to the non-marine realm.  相似文献   

5.
The seventh and largest known dinosaur tracksite from the Cedar Mountain Formation is reported from two important stratigraphic levels in the Ruby Ranch Member within the boundaries of Arches National Park. Previous reports of sites with a few isolated tracks are of limited utility in indicating the fauna represented by track makers. The Arches site reveals evidence of several theropod morphotypes, including a possible match for the coelurosaur Nedcolbertia and an apparently didactyl Utahraptor-like dromeosaurid. Sauropod tracks indicate a wide-gauge morphotype (cf. Brontopodus). Ornithischian tracks suggest the presence of an iguandontid-like ornithopod and a large ankylosaur. Dinosaur track diversity is high in comparison with other early Cretaceous vertebrate ichnofaunas, and it correlates well with faunal lists derived from skeletal remains, thus providing a convincing census of the known fauna.  相似文献   

6.
Recent collections from six sections in Lanongla area,Tethyan Himalaya allow the establishment of four buchia assembles.In ascending they are Buchia-Buchia spitiensis,Buchia masquensis-Buchia rugasa,Buchia blanfordiana,Buchia piochii and Buchia subokensis assemblages.These Buchia assemblages first demonstrate that not only the Upper Jurassic strata but also the highest Buchia assemblage-Buchia subokensis,which appeared in Lower Cretaceous strata all over the world are present in Lanongla area.This first records the highest Buchia assemblage in Lanongla area.  相似文献   

7.
The Yixian Formation of Liaoning Province, People's Republic of China has yielded a diverse fauna of non-avian dinosaurs, but is dominated by small-bodied taxa. Here, we describe a series of isolated teeth from the Lujiatun Beds of the formation that are referable to a basal titanosauriform sauropod. Some of the teeth possess a distinctive circular boss on the lingual surface, which suggests that they are referable to cf. Euhelopus sp. This identification provides some additional support for biostratigraphical correlations between the Jehol Group and the Mengyin Formation of Shandong Province that suggest an Early Cretaceous age for the latter unit. Moreover, the titanosauriform affinities of the teeth provide further evidence for the dominance of this sauropod clade in eastern Asia during the Cretaceous.  相似文献   

8.
Recent collections from six sections in Lanongla area, Tethyan Himalaya allow the establishment of four buchia assemblages. In ascending order, they are Buchia-Buchia spitiensis, Buchia masquensis-Buchia rugasa, Buchia blanfordiana, Buchia piochii and Buchia subokensis assemblages. These Buchia assemblages first demonstrate that not only the Upper Jurassic strata but also the highest Buchia assemblage-Buchia subokensis, which appeared in Lower Cretaceous strata all over the world are present in Lanongla area. This first records the highest Buchia assemblage in Lanongla area. __________ Translated from Acta Scientiarum Naturalium Universitatis Pekinensis, 2005, 41 (4) [译自: 北京大学学报( 自然科学版), 2005,41(4)]  相似文献   

9.
The Lower Cretaceous Ilek Formation in Western Siberia (Russia) has yielded various vertebrate fossils, including skeletal remains of dinosaurs. Here we report on a fragmentary theropod egg from the vertebrate locality Shestakovo 3 of the Ilek Formation in Kemerovo Province. We assign the specimen to the oogenus Prismatoolithus (oofamily Prismatoolithidae) as Prismatoolithus ilekensis oosp. nov., on the basis of the following unique combination of characters: ovoid-shaped egg; thin eggshell 300–330 μm thick; angustiprismatic morphotype; eggshell with three different layers; gradual transition between mammillary layer and prismatic layer; abrupt contact between prismatic layer and external layer; mammillary layer to prismatic layer to external layer thickness ratio is 1:3:0.6; prismatic layer with ill-defined squamatic texture; angusticanaliculate pore system; and smooth outer surface. Like other Early Creataceous Prismatoolithus, the egg of Prismatoolithus ilekensis oosp. nov. was laid by a small bodied theropod dinosaur (troodontid or primitive bird) and this taxonomic attribution is supported by results of our phylogenetic analysis. Prismatoolithus ilekensis oosp. nov. is the first Early Cretaceous ootaxon from Russia.

urn:lsid:zoobank.org:act:734EAD40-86C3-488B-A61E-B5FF7378BC0E  相似文献   


10.
Abstract: A new genus and species, Ogunichthys triangularis, from the Early Cretaceous Marizal Formation in the Tucano Basin, Bahia State, Brazil, can be assigned to the teleost order Ichthyodectiformes and to the suborder Ichthyodectoidei by the presence of ten synapomorphies of these clades. Ogunichthys gen. nov. cannot be placed into any of the currently recognized families within Ichthyodectoidei and differs from all other ichthyodectoid genera in the ratio between the depth of the dentary symphysis and the depth of the coronoid process, the relationships between the length of the coronoid process and the alveolar border of the dentary, and a supraoccipital crest with posterior border fringed. The new taxon occurs in Early Cretaceous (Aptian) strata of the Marizal Formation, which are related to periods during epicontinental seas extended from the Caribbean Tethys into the South American continent. Rather than representing a single continuous widespread seaway, these epicontinental seas reflect local tectonic events, sometimes including locally distinctive faunas.  相似文献   

11.
O. Szives  & N. Monks 《Palaeontology》2002,45(6):1137-1149
An important new ammonite fauna was collected by Fülöp in 1953 and 1960 from basal lenses between a Tithonian hardground and the overlying Tata Limestone Formation containing many heteromorph ammonites. This assemblage of ammonites has been determined as being of Early Albian ( tardefurcata Zone) age. Among the heteromorphs are species of Tonohamites and Ptychoceras , which are familiar components of Late Aptian or Early Albian ammonite faunas. The genera Ephamulina , Hamites and Protanisoceras are also recorded, the earliest species of which had previously come from sediments of late Early Albian ( mammillatum Zone) age. While Hamites and Protanisoceras are common in Europe, Ephamulina had previously only been known from Madagascar. The discovery of Ephamulina , Hamites and Protanisoceras supports the view that these phylogenetically significant ammonites had radiated close to the Aptian/Albian boundary. Four new species of Hamites ( H. czaszari , H. fazekasensis , H. fueloepi and H. kalvariensis ) and one new species of Tonohamites ( T. boldii ) are described.  相似文献   

12.
Extensive sampling of several Barremian and Albian–Cenomanian levels across the Aguilón, Oliete and Aliaga subbasins of the Iberian Basin, north‐east Spain, yielded abundant material of new or so far poorly known neoselachians. The faunas consist of 16 different species, five of which represent new species and two new genera: Cantioscyllium brachyplicatum sp. nov. , Platypterix venustulus gen. et sp. nov. , Ptychotrygon pustulata sp. nov. , Ptychotrygon striata sp. nov. and Iberotrygon plagiolophus gen. et sp. nov. In addition, teeth of Heterodontus cf. H. carerens, Lamniformes indet., Pteroscyllium sp., Scyliorhinidae indet., Rhinobatos sp., Spathobatis sp., Belemnobatis sp., Ptychotrygon geyeri, Ptychotrygon sp. and Celtipristis herreroi are described. The new family Ptychotrygonidae is defined. The localities comprise palaeoenvironments ranging from lacustrine and shallow lake to open marine settings. Neoselachians are almost completely absent from continental settings in the Barremian, as a result of prevailing freshwater conditions, but became more abundant in marine strata. The Albian–Cenomanian selachian assemblage is the most profuse and diverse of the three assemblages studied. It is dominated by small, benthic and near‐coastal taxa, for instance Cantioscyllium and Ptychotrygon, and contains several new species, including an endemic batoid, Iberotrygon plagiolophus gen. et sp. nov. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 316–347.  相似文献   

13.
Neeru Prakash   《Palaeoworld》2008,17(3-4):253
The Jabalpur Formation of Jabalpur series, named after Jabalpur city in Central India, is exposed along the Narbada River, in Satpura Basin. The series is divided into the lower Chaugan and the upper Jabalpur stages. The Jabalpur beds occur between Mahadevas and Lametas at Mahadeva Hills, exhibit highest Gondwanan strata, and embody diversified flora. These beds also extend laterally to Bairam and Belkher areas in western part of central India. The highest diversity of the floral assemblage is recorded in the central portion of the basin (Sehora and Hasnapur) whereas the lowest diversity is recorded in Morand River, Parsapani and Tilaksindoor areas. The diversity in floral assemblage indicates the dominance of conifers and pteridophytes along with cycadophytes and certain pteridosperms. The palynofloral assemblage from this formation contains pollen and spores of bryophytic, pteridophytic and gymnospermic groups. The palaeovegetational diversity, biostratigraphic correlation and phytogeographic distribution of the Jabalpur flora are discussed in comparison with various coeval floras of Indian peninsula along with contemporaneous deposits of the other Gondwanan regions. The palaeogeographic analysis suggests that the flora was thriving as mixed vegetation during Early Cretaceous under seasonally hot and dry or alternating with wet and dry condition.  相似文献   

14.
15.
Sauropod dinosaurs are poorly represented in the Lower Cretaceous of eastern Asia. Here, we describe a number of isolated sauropod teeth from the Kuwajima Formation (?Berriasian–?Hauterivian) of Shiramine, Japan. The mosaic of shared derived characters and symplesiomorphies displayed by the teeth indicate that they are referable to a basal member of the titanosauriform radiation. A taxonomic review of previously described sauropod specimens from eastern and south–eastern Asia reveals that a diversity of sauropods (including a titanosaurian, a basal titanosauriform and a ?euhelopodid, as well as several forms of indeterminate systematic position) was present in this region in the Early Cretaceous. This diversity conflicts with previous suggestions that eastern Asia was biogeographically isolated from the rest of Laurasia until the late Early Cretaceous and that the sauropod fauna was limited to the endemic East Asian clade Euhelopodidae. The presence of titanosauriform sauropods in the basal Cretaceous of Japan and Thailand indicate that the proposed faunal isolation of eastern Asia ended approximately 20 myr earlier than usually suggested.  相似文献   

16.
The vertebrate fauna from the Lower Cretaceous Patuxent Formation of Virginia is composed of a single partial fish impression from the James River at Dutch Gap and a diverse tetrapod ichnofauna from near Fredericksburg that includes trace fossils made by frogs, turtles, theropods, sauropods, ankylosaurs, and ornithopods. The footprints occur on overbank deposits preserved locally within a fluvial braided-stream sequence that formed near the western border of the Early Cretaceous Atlantic Coastal Plain.  相似文献   

17.
《Palaeoworld》2014,23(3-4):314-320
Four recently collected mammal specimens from the Upper Cretaceous (Santonian–?Campanian) Bostobe Formation in the northeastern Aral Sea Region, Kazakhstan are attributed to Asioryctitheria indet. (an edentulous dentary fragment) and the zhelestid Parazhelestes sp. cf. P. mynbulakensis (a maxillary fragment with a double-rooted canine, an M1, and a dentary fragment including m3). These new records double the known mammal fauna from this formation, which previously included the zhelestid Zhalmouzia bazhanovi and Zhelestidae indet. The taxonomic and ecological structure of the mammal assemblage from the Bostobe Formation can, on present evidence, be considered close to the other eutherian dominated Late Cretaceous mammal assemblages of Central Asia. This region is important in particular in the search for Late Cretaceous ancestors of crown-group eutherian mammal clades (Placentalia).  相似文献   

18.
Fossil record of Early Cretaceous birds may be geographically biased, and eggs and eggshells predating the Late Cretaceous were unknown. Here, we report the oldest known bird eggshell (FPDM-V-0009175) collected from the upper Barremian Kitadani Formation in Katsuyama City, Fukui, Japan. The Kitadani Formation likely represents fluvial environments. Thin-section and scanning electron microscope analyses revealed diagnostic characters of FPDM-V-0009175, including thin (0.44 mm) shell, smooth external surface, non-branching and narrow pore canals with relatively constant width, three structural layers, oblique crystal orientation from vertical in the external layer, and mammillary to continuous to external layer thickness ratio of 1:1:0.44. These characters allow assignment of FPDM-V-0009175 to a new oogenus and oospecies, Plagioolithus fukuiensis, and suggest it belonging to a bird. The three-layered eggshell structure is seen in extant and extinct birds, Plagioolithus fukuiensis, and non-avian theropods. Therefore, such structure may be plesiomorphic among theropods, appearing in the late Barremian or earlier. As the first bird body fossil from the Mesozoic of Japan, Plagioohlithus fukuiensis suggests extensive distribution and abundance of birds in the Barremian East Asia. Plagioolithus fukuiensis indicates that the late-Barremian birds inhabited and reproduced in the fluvial environments within a basin located along the eastern margin of the Asian continent.http://www.zoobank.org/urn:lsid:zoobank.org:pub:90A8CCE8-57F7-473C-855C-B2CCE2BBD1A2  相似文献   

19.
Clam shrimps have been recognized as a key group for the study of reproductive system evolution, owing to the diversity of sexual systems in extant members. However, there are comparatively little data on fossil taxa. In this study, we reveal the sexual system of the Early Cretaceous clam shrimp Eosestheria middendorfii (Yixian Formation, China). This is the first study that restricts the analysis to a single cohort, minimizing the otherwise considerable impact of ecophenotypic variation within this species. In addition, the presence of egg clutches, which identifies some individuals as either female or hermaphroditic, serves as an independent indicator for sex prior to the statistical treatment of the data. Obligate sexuality (‘dioecy’) is the inferred reproductive system for E. middendorfii and sexual dimorphism accounts for about 10% of the adult shape variation. Carapace shape variation resulting from malformation and deformation is more pronounced than the underlying sexual dimorphism. Subtle sexual dimorphism, smaller and slightly more elongate females, lateral egg clutches, and egg diameters of about 140 μm indicate that E. middendorfii is closely allied with the extant family Cyzicidae.  相似文献   

20.
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