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1.
The Haţeg and Rusca Montană basins (South Carpathians, Romania) yield a rich Late Cretaceous (Maastrichtian) compressive megafloral assemblage represented by ferns, conifers, monocotyledons and dicotyledons. This paper focuses on the dicotyledons of these basins, based on recently collected material as well as on historical collections of the University of Bucharest, including the Dincă and Răileanu collections, and of the Babeş-Bolyai University of Cluj-Napoca, with the Petrescu and Duşa collection. The dicotyledonate association is represented by Araliaephyllum sp., Credneria denticulata, Ettingshausenia onomasta, Ettingshausenia sp., and five other dicotyledon types, a taxonomically much less diverse assemblage than previously published. Differences with regard to the previous taxa lists of the Haţeg and Rusca Montană basins are due to the reinterpretation of the fossil material in the light of recent advances in the field, especially when considering a higher variation of the leaf material, its preservation and its taphonomy. 相似文献
2.
Gully erosion is both a significant natural hazard and an important sediment source. The design of proper prevention measures relies firstly on the prediction of the future locations of gullies. But, as recent progress has shown, methods and results in any environmental modelling greatly depend upon scale, the selection of which should be based on management needs. This research deals with predicting the spatial potential for gullying at two different scales grouped in a top-down framework, i.e. starting with a preliminary, regional scale analysis (1:100,000–1:200,000) to develop a simplified model, and performing a more detailed, intermediate level analysis at a medium scale (1:25,000–1:50,000) for the basin sector revealed as the most threatened by the process. At the same time, the study searches for relationships among: scale of analysis, area of investigation, precision and accuracy of input data, and the quality of expected results and their applicability. The study area is the Olteţ Drainage Basin (2439 km2) in southern Romania, which extends over four landform types: mountains, hills, a plateau (piedmont) and a plain. Aiming to investigate the scale effect, the same statistical method is selected for both analyses, namely Classification and Regression Trees (CART). Scale-adapted procedures and resolutions are applied for defining the dependent variable, deriving the environmental attributes and deciding the sampling strategy needed to provide information for the statistical analyses. In order to detect the degree of gullying at the regional scale, the statistical method is used over the entire basin, and gully density is selected as the target variable. For the analysis of gully susceptibility at the medium scale, within the most affected area of the Olteţ Basin identified as the piedmont sector, the single gully and the intensely gullied spot are defined as the target variables. The best validated maps obtained at the two scales are compared. The results reveal that both individual maps are characterized by statistical accuracy (a NRMSE value of 0.05–0.08 and an AUC of 0.86 for the regional scale and the medium scale models, respectively). Yet, the regional scale map is affected by high uncertainties when compared to the medium scale one. The scale dependency of results and hence the relative nature of their accuracy and reliability are highlighted in the context of both fundamental and applied research. 相似文献
3.
A new bird from the early Cretaceous Yixian Formation of Liaoning, China is described. This new species, Grabauornis lingyuanensis, shares several synapomorphies with the Enantiornithes. The specimen is relatively well preserved. The skeletal morphology of Grabauornis bears close resemblance to that of other Chinese members of this clade. The brachial index (the ratio between the lengths of humerus and ulna) is 0.95, which is close to the average for enantiornithine birds. It indicates that Grabauornis was a rather good flyer, and the presence of an alula in the wing further testifies to this. 相似文献
4.
A new dinosaur of Early Cretaceous age was recently discovered from the Mazongshan area of northwestern Gansu Province, China. The new dinosaur represents a new genus and species of Sauropoda, and is among the most basal members of Titanosauria. Its finding also suggests that titanosaurs might have originated in Asia no later than the Early Cretaceous. 相似文献
5.
A new species, Cimbrophlebia rara sp. nov., in the family Cimbrophlebiidae(Mecoptera) is described and illustrated. This specimen was collected from the Early Cretaceous Yixian Formation at Liutiaogou in Inner Mongolia, China. This is the first record of a cimbrophlebiid from the Jehol biota. A key to all species of Cimbrophlebia is given. A preliminary review of published taxa data indicates that from the Middle Jurassic to the Early Cretaceous, Mecoptera became less diverse and less abundant in northeastern China at familiar level(from 11 to 6), generic level(from 32 to 8) and specific level(from 44 to 14). 相似文献
6.
A new fossil species,Anthoscytina macula sp.nov.,of the family Procercopidae is described from the Early Cretaceous Yixian Formation in Huangbanjigou,Chaomidian Village,Beipiao City,Liaoning Province,China.A key to the species of the genus Anthoscytina Hong,1983 is provided.The diagnosis of the genus is revised. 相似文献
7.
A new large-bodied theropod dinosaur,Datanglong guangxiensis gen.et sp.nov.,was recovered from the Lower Cretaceous Xinlong Formation of the Datang Basin,Guangxi.It is unique in several features including:posteriormost dorsal vertebra with teardrop-shaped pneumatic foramen confined by enlarged pcdl,acpl and the centrum; posteriormost dorsal with well-developed,horizontal prpl; posteriormost dorsal with a parapophysis projecting more laterally than the diapophysis; brevis fossa shallow with short,ridge-like medial blade; and iliac pubic peduncle with posteroventrally expanded margin.Cladistic analysis supports the idea that this new taxon Datanglong guangxiensis is a primitive member of the Carcharodontosauria in possessing two unambiguous synapomorphies:large external pneumatic foramina and internal spaces present in the lateral surface of ilium,and a peg-and-socket ischiac articulation with the ilium.The presence of the new taxon from Guangxi further confirms that Carcharodontosauria were cosmopolitan large-bodied predators during the Early–mid Cretaceous. 相似文献
8.
Charophytes from uppermost Campanian to Paleocene deposits in the Pingyi Basin (Shandong Province, Eastern China) are studied from the perspectives of taxonomy, paleoecology, biogeography, and biostratigraphy. The taxonomy of charophytes used by previous authors is revisited based on a study of intraspecific gyrogonite polymorphism, facilitating comparisons between China and Europe. A number of synonymies are proposed. Gobichara deserta is confirmed as a younger synonym of Microchara cristata. The genus Euaclistochara Z. Wang is shown to be a younger synonym of Lamprothamnium J. Groves. Charophyte assemblages from the Pingyi Basin were generally species-poor but showed a high degree of variation depending on the paleoenvironment. During the latest Campanian–Maastrichtian, brackish water assemblages were monospecific, formed by Feistiella anluensis. Permanent lakes were dominated by Microchara cristata and Peckichara praecursoria. Lamprothamnium ellipticum and Mesochara voluta inhabited the overbank ponds near braided rivers. The Paleocene was much more homogeneous and was dominated by Peckichara varians in permanent lakes. A new biozonation is proposed which encompasses two biozones based on species with broad paleoecological requirements and a Eurasiatic distribution. These are the Microchara cristata biozone starting in the latest Campanian and lasting at least until the earliest Danian and the Peckichara varians biozone encompassing the late Danian–earliest Eocene. These biozones allow direct correlation between Chinese and European basins. 相似文献
9.
A new partial specimen of Zhenyuanopterus from the Lower Cretaceous Yixian Formation of Beipiao city, Liaoning Province is described. This specimen is slightly larger than half the size of the holotype. Although it is not complete, it provides new information on Zhenyuanopterus both in taxonomy and ontogeny: the total number of the caudal vertebrae is 15; the forelimb is more robust than the hindlimb; the growth rate of the humerus and femur is constant, and their ratio is about 1. Compared with the holotype, the scapula and coracoid grow faster than the humerus and the femur. The scapula and coracoid may slow their growth rate after a certain ontogenetic stage. The pectoral girdle, robust forelimb and weak hindlimb of the new material(XHPM1088) together with data from the holotype of Zhenyuanopterus indicate that this taxon spent less time on land than in the sky or other ecological niches such as forests and cliffs. 相似文献
10.
Funiusaurus luanchuanensis gen. et sp. nov. was described on the basis of an incomplete skull from the Upper Cretaceous Qiupa Formation of the Tantou Basin in Luanehuan County, Henan Province. It is the second representative of lizards known from Luanchuan and adds a new member to the Luanchuan Fauna. F. luanchuanensis is a small-sized lizard and systematically assigned to the Polyglyphanodontidae of the Teiioidea because of the presence of a caniniform tooth and an elongate posterior process of the postorbital. It is distinctive in that the heterodont dentition bears 19 teeth in both the upper and lower jaws, the 3^rd maxillary tooth is large and caniniform, the post-caniniform teeth in maxilla and those posterior to the 3^rd dentary tooth are chisel-like in lateral view, the prefrontal possesses a fossa on its lateral surface, the postorbital with an extremely elongate posterior process and the well-developed retroarticular process has a deep fossa on its dorsal surface. In phylogeny, our analysis suggests a close relationship of Funiusaurus to the large-sized Tianyusaurus from the same basin within the Tuberocephalosaurinae. The discovery of Funiusaurus is significant in confirming the status of the Tuberocephalosaurinae, which includes a group of the Asian members of the Polyglyphanodontidae only. 相似文献
11.
An almost complete skull, which was collected from the Upper Cretaceous of the Bayan Mandahu area in Inner Mongolia, China by the Sino-Canadian Dinosaur Project, is described and assigned to a new genus of protoceratopsid dinosaur, Magnirostris dodsoni gen. et sp. nov. This new taxon is distinguished from other protoceratopsids by the robust rostral bone and the existence of incipient orbital horn cores. The existence of an additional antorbital fenestra indicates a close relationship between Magnirostris and Bagaceratops. 相似文献
12.
Our results present a taxonomic and palaeoecological study on non-marine gastropods from the latest Cretaceous to Paleocene deposits of the Pingyi Basin, Shandong Province, eastern China. These gastropods are systematically described: three species belonging to three genera including Physa dongtaiensis Gu, 1989, Hydrobia datangensis Yü, 1977, and the newly established species Cyathopoma pingyiensis sp. nov.; two indeterminata genera and species including Truncatelloidea gen. et sp. indet., and Pomatiopsidae gen. et sp. indet. Among them, Truncatelloidea gen. et sp. indet. and Cyathopoma pingyiensis sp. nov. are the dominant species with the longest record. Cyathopoma pingyiensis, sp. nov. is the earliest representative of this widely distributed Asian extant genus. Sedimentological facies analysis of the gastropod-bearing beds suggested that Truncatelloidea gen. et sp. indet. lived in a small pond with a river inlet and a shallow lake, while Ph. dongtaiensis, ?Pomatiopsidae gen. et sp. indet, and ? H. datangensis only thrived in the shallow lake. Cyathopoma pingyiensis sp. nov. inhabited the land area around the shallow lake. Our results showed that no significant species change of the gastropod fauna across the K/Pg (Cretaceous/Paleogene) boundary was observed in the Pingyi Basin. 相似文献
13.
Based on a new nearly naturally preserved skull and four cervical vertebrae of the pterosaur Feilongus sp. from the lower Cretaceous Jiufotang Formation of Beipiao, western Liaoning province, northeastern China, the diagnosis of Feilongus is amended. The revised diagnosis notes long, curved, needle-shaped teeth that are confined to the jaw far anterior to the nasoantorbital fenestra; posterior teeth that are slightly smaller than the anterior teeth; cervical vertebrae elongated with a ratio of length to width greater than 5; tooth number of about 78; and two cranial sagittal crests. 相似文献
14.
Mawsoniids are a lineage of extinct fresh/brackish water coelacanth fishes, common in Cretaceous Godwanan deposits of South America, North and West Africa and Madagascar. Here we formally describe mawsoniid remains from the fluvio-lacustrine Missão Velha Formation (Lower Cretaceous) of the Araripe Basin, North-East Brazil. The examples from the Missão Velha Formation are here described as Mawsonia cf. gigas, based mainly on elements of the lower jaw and opercular series. The occurrence of M. cf. gigas in the Missão Velha Formation expands the stratigraphic and geographical ranges of the type species. 相似文献
16.
Based on a nearly complete skeleton with skull from the Early Cretaceous of Liaoning Province, a new ornithocheirid pterosaur: Boreopterus cuiae gen. et sp. nov. is erected. Boreopterus cuiae is different from other pterosaurs preserved with skulls known from the western Liaoning Province and its neighboring areas. Tiffs new oterosaur has more and larger teeth than those in other ornithocheirids. Its anterior nine pairs of teeth are larger than other teeth. The fourth pair of upper and lower teeth are slightly larger than the third pair. Overall, Boreopterus cuiae shows much small range of tooth size variation than Anhanguerapiscator and Coloborhynchus robustus. The new taxon shares with other ornithocherids in having a relatively large size of the third and fourth pairs of teeth. 相似文献
17.
Plant–arthropod interactions provide the first relevant data for addressing evidence of phytophagy for an assemblage of coniferous silicified woods from the pre-rift phase in the Araripe Basin, Brazil. A complex system of borings, sometimes filled with small, oval to hexagonal coprolites, allow inferences to be made about the activities of termites (Isoptera). Previous dendrological data indicated that the climate during the Early Cretaceous on the landmasses of the northern Afro-Brazilian Depression was dry and savanna like, where termite borings were common. Features of wood preservation demonstrate that the damage was probably caused by herbivores, not detritivores. 相似文献
18.
Basal iguanodontians (“iguanodontids”) were a successful group of ornithopod dinosaurs that attained a near global distribution by the late Early Cretaceous. Despite their body fossils being known in abundance from the uppermost Jurassic and Lower Cretaceous of the western United States, their remains have never been found in western Canada. With its extensive, terrestrial sedimentary record for the whole of the Early Cretaceous, the expectation is that these dinosaurs would have been present in western Canada. This paper reports the finding of a fossil footprint from the Gladstone Formation in southwestern Alberta that is interpreted to have been made by an iguanodontid. This identification is based on the late Barremian age of the hosting rock, gross footprint details that match the skeletal foot structure of Iguanodon bernissartensis, and similarities to Early Cretaceous dinosaur footprints found elsewhere in the world that are attributed to iguanodontids. This finding fills a noticeable gap in the iguanodontian fossil record, and is consistent with the clade's attainment of global distribution during the Early Cretaceous. 相似文献
19.
Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are (in ascending order): the lmpardecispora-Aequitriradites- Clawttipollenites assemblage; the Triporoletes-Pilosisporites-Asteropollis assemblage; and the Appendicisporites- Asteropollis-Tricolpites assemblage, distributed in Members 1, 2 and 3 of the Yimin Formation respectively. Recognition of this biostratigraphic sequence is very important for the division and correlation of the Yimin Formation in the basin. Meanwhile, the age of the Yimin Formation is considered to be Barremian to Early Albian based on the palynological data. 相似文献
20.
A new ankylosaurid species of Crichtonsaurus,C.benxiensis sp.nov.,is erected based on a well preserved skeleton and a nearly complete skull found in the Sunjiawan Formation(Cenomanian- Turonian),Beipiao,Liaoning Province.Crichtonsaurus benxiensis sp.nov.is characterized by width 84.6% of length of the skull,a deep depression located medial to the notch between the orbit and the squamosal horn,paroccipital processes fused to the quadrates,fused scapula and coracoid,a large foramen for the supracoracoid nerve to enter the coracoid and to exit out from the scapula.Based on the new specimen,Crichtonsaurus is assigned to Ankylosauridae. 相似文献
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