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1.
Late Cretaceous gastropod dominated communities of the Western Tarim Basin, Southern Xinjiang, China
PAN HUA-ZHANG 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1990,23(3):273-289
Late Cretaceous strata of the Western Tarim Basin, Southern Xinjiang, China are divided into the Kukebai, Wuyitake. Yigeziya and Tuyilouk Formations. The gastropod faunas can be arranged into six communities corresponding to broad depositional environments. Two communities commonly occur in the nearshore shoal environments: the Vernedia pusillina Community from the Lower Member of the Kukebai Formation and the Trochactaeon (Neocylindrites)-Actaeonella Community from the Lower Member of the Yigeziya Formation. Three communities occur in the shelf environments: these are the Helicaulax and Ascensovoluta-Gyrodes Communities of the lower and upper parts of the Upper Member of the Kukebai Formation respectively and the Ampullina-Cantharus Community of the Middle-Upper Member of the Yigeziya Formation. A hypersaline environment is indicated by the Haustator-Corbula Community from the Middle Member of the Kukebai Formation. 相似文献
2.
记述了山西天镇晚白垩世灰泉堡组发现的一鸭嘴龙超科恐龙新属种:天镇大同龙Datonglong tianzhenensis gen.et sp.nov.。标本为一保存较完好的右侧齿骨并带牙齿。与其他鸭嘴龙超科恐龙不同,大同龙每个齿槽有两个功能齿,而且舌面齿冠上嵴的发育也具有独特的特征组合(主嵴向远中方向偏移;次嵴发育;无其他附嵴;主嵴上半段略后弯)。对比研究发现,在较进步的非鸭嘴龙科鸭嘴龙超科类群中齿骨和牙齿的演化过程复杂,许多鸭嘴龙科的特征在这些类群中时而出现,如:巴克龙Bactrosaurus齿冠具有较大的高/宽比;吉尔摩龙Gilmoreosaurus齿冠上只有一个主嵴和纤弱的附嵴;张衡龙Zhanghenglong齿冠上主嵴中置;南宁龙Nanningosaurus下颌冠状突前倾;大同龙Datonglong每个齿槽有两个功能齿。这表明为了获得更有效的牙齿咀嚼方式,在鸭嘴龙科起源前它的姐妹群们曾进行过多种尝试;这也告诫我们,受大量趋同演化的影响,要厘清这些类群间的关系并非易事。 相似文献
3.
A new genus and species of Nanhsiungchelyidae (Testudines: Cryptodira), Yuchelys nanyangensis n. g. n. sp., are described on the basis of a partial skeleton from the Late Cretaceous Gaogou Formation of Neixiang, Nanyang Basin, Henan Province. It is the first nanhsiungchelyid record in the east-central part of China and fills the geographical gap between the western (Uzbekistan, Mongolia, Northern and Southern China) and eastern (Japan) distribution areas of the family Nanhsiungchelyidae. 相似文献
4.
Run-Fu Wang Hai-Lu You Shi-Chao Xu Suo-Zhu Wang Jian Yi Li-Juan Xie Lei Jia Ya-Xian Li 《PloS one》2013,8(10)
Background
The origin of hadrosaurid dinosaurs is far from clear, mainly due to the paucity of their early Late Cretaceous close relatives. Compared to numerous Early Cretaceous basal hadrosauroids, which are mainly from Eastern Asia, only six early Late Cretaceous (pre-Campanian) basal hadrosauroids have been found: three from Asia and three from North America.Methodology/Principal Findings
Here we describe a new hadrosauroid dinosaur, Yunganglong datongensis gen. et sp. nov., from the early Late Cretaceous Zhumapu Formation of Shanxi Province in northern China. The new taxon is represented by an associated but disarticulated partial adult skeleton including the caudodorsal part of the skull. Cladistic analysis and comparative studies show that Yunganglong represents one of the most basal Late Cretaceous hadrosauroids and is diagnosed by a unique combination of features in its skull and femur.Conclusions/Significance
The discovery of Yunganglong adds another record of basal Hadrosauroidea in the early Late Cretaceous, and helps to elucidate the origin and evolution of Hadrosauridae. 相似文献5.
Dangpeng Xi Shun Li Xiaoqiao Wan Xia Jing Qinghua Huang Jean-Paul Colin Zhuo Wang Weiming Si 《Hydrobiologia》2012,688(1):113-123
High-resolution biostratigraphy has been established on the basis of fossil ostracodes from cores of the Cretaceous Continental
Scientific Drilling borehole-Songke 1 (south) (SK1(s)) in the Songliao Basin, northeast China. More than 80 species belonging
to 13 genera have been identified and 15 ostracode assemblage zones have been recognized. On the basis of ostracode paleoecological
analysis, paleoenvironments, for example lake levels and salinity, have been reconstructed. Two inferred deep-water phases
occurred during the deposition of the lower Qingshankou and lower Nenjiang formations, whereas shallower water phases probably
occurred during deposition of the upper Quantou and uppermost Qingshankou to Yaojia formations. The salinity of paleo-Songliao
lake is interpreted as predominantly freshwater to oligohaline. Oligohaline to mesohaline water environments may have occurred
during the first and middle third members of the Qingshankou formation and the lower first and lower second members of the
Nenjiang formation. 相似文献
6.
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
7.
8.
A new genus and new species of lindholmemydid turtle (Cryptodira: Testudinoidea), Shandongemys dongwuica n. g. and n. sp. are described on the basis of a partial skeleton with incomplete shell and skull, complete lower jaws and disarticulated limb bones from the Upper Cretaceous Wangshi Group of Zhucheng, Shandong Province, China. Among Lindholmemydidae, the new species is closely related to Mongolemys elegans from the Late Cretaceous of Mongolia. An incomplete shell from the same locality is referred as Lindholmemydidae indet. Glyptops sp. from the Upper Cretaceous Wang Group of Jingangkou, Laiyang, Shandong is revised and assigned to Lindholmemydidae. 相似文献
9.
Here we report on three new species of ornithuromorph birds from the Lower Cretaceous Xiagou Formation in the Changma Basin of Gansu Province, northwestern China: Yumenornis huangi gen. et sp. nov., Changmaornis houi gen. et sp. nov., and Jiuquanornis niui gen. et sp. nov.. The last of these is based on a previously published but unnamed specimen: GSGM-05-CM-021. Although incomplete, the specimens can be clearly distinguished from each other and from Gansus yumenensis Hou and Liu, 1984. Phylogenetic analysis resolves the three new taxa as basal ornithuromorphs. This study reveals previously unrecognized ornithuromorph diversity in the Changma avifauna, which is largely dominated by Gansus but with at least three other ornithuromorphs. Body mass estimates demonstrate that enantiornithines were much smaller than ornithuromorphs in the Changma avifauna. In addition, Changma enantiornithines preserve long and recurved pedal unguals, suggesting an arboreal lifestyle; in contrast, Changma ornithuromorphs tend to show terrestrial or even aquatic adaptions. Similar differences in body mass and ecology are also observed in the Jehol avifauna in northeastern China, suggesting niche partitioning between these two clades developed early in their evolutionary history. 相似文献
10.
描述了江西晚白垩世南雄组产出的两颗大型兽脚类恐龙牙齿。这两颗牙齿的齿冠高度分别为91和76 mm左右。较小牙齿近似圆锥形,齿冠基部比率为0.72,与典型的暴龙类牙齿相似。较大牙齿横向侧扁,齿冠基部比率约为0.47,舌侧和唇侧表面近乎平坦,前后缘冠面基部发育明显的纵向褶皱,区别于已发现的暴龙科、鲨齿龙科和棘龙科成员的牙齿。江西大型兽脚类恐龙牙齿的发现对于全面了解华南地区南雄组多样化的脊椎动物群组成具有一定的意义。 相似文献
11.
Paleontological Journal - The xylotomy of the silicified wood from the Late Jurassic to Early Cretaceous Kota Formation of the Pranhita-Godavari Basin is studied and its systematic affinity is... 相似文献
12.
Increased excavation of dinosaurs from China over the last two decades has enriched the record of Asian titanosauriform sauropods. However, the relationships of these sauropods remain contentious, and hinges on a few well-preserved taxa, such as Euhelopus zdanskyi. Here we describe a new sauropod, Yongjinglong datangi gen. nov. et sp. nov., from the Lower Cretaceous Hekou Group in the Lanzhou Basin of Gansu Province, northwestern China. Yongjinglong datangi is characterized by the following unique combination of characters, including seven autapomorphies: long-crowned, spoon-shaped premaxillary tooth; axially elongate parapophyses on the cervical vertebra; very deep lateral pneumatic foramina on the lateral surfaces of the cervical and cranial dorsal vertebral centra; low, unbifurcated neural spine fused with the postzygapophyses to form a cranially-pointing, triangular plate in a middle dorsal vertebra; an “XI”-shaped configuration of the laminae on the arches of the middle dorsal vertebrae; a very long scapular blade with straight cranial and caudal edges; and a tall, deep groove on the lateral surface of the distal shaft of the radius. The new specimen shares several features with other sauropods: a pronounced M. triceps longus tubercle on the scapula and ventrolaterally elongated parapophyses in its cervical vertebra as in Euhelopodidae. Based on phylogenetic analyses Yongjinglong datangi is highly derived within Titanosauria, which suggests either a remarkable convergence with more basal titanosauriform sauropods in the Early Cretaceous or a retention of plesiomorphic features that were lost in other titanosaurians. The morphology and remarkable length of the scapulocoracoid reveal an unusual relationship between the shoulder and the middle trunk: the scapulocoracoid spans over half of the length of the trunk. The medial, notch-shaped coracoid foramen and the partially fused scapulocoracoid synostosis suggest that the specimen is a subadult individual. This specimen sheds new light on the diversity of Early Cretaceous Titanosauriformes in China. 相似文献
13.
Studying the evolution and biogeographic distribution of dinosaurs during the latest Cretaceous is critical for better understanding the end-Cretaceous extinction event that killed off all non-avian dinosaurs. Western North America contains among the best records of Late Cretaceous terrestrial vertebrates in the world, but is biased against small-bodied dinosaurs. Isolated teeth are the primary evidence for understanding the diversity and evolution of small-bodied theropod dinosaurs during the Late Cretaceous, but few such specimens have been well documented from outside of the northern Rockies, making it difficult to assess Late Cretaceous dinosaur diversity and biogeographic patterns. We describe small theropod teeth from the San Juan Basin of northwestern New Mexico. These specimens were collected from strata spanning Santonian – Maastrichtian. We grouped isolated theropod teeth into several morphotypes, which we assigned to higher-level theropod clades based on possession of phylogenetic synapomorphies. We then used principal components analysis and discriminant function analyses to gauge whether the San Juan Basin teeth overlap with, or are quantitatively distinct from, similar tooth morphotypes from other geographic areas. The San Juan Basin contains a diverse record of small theropods. Late Campanian assemblages differ from approximately co-eval assemblages of the northern Rockies in being less diverse with only rare representatives of troodontids and a Dromaeosaurus-like taxon. We also provide evidence that erect and recurved morphs of a Richardoestesia-like taxon represent a single heterodont species. A late Maastrichtian assemblage is dominated by a distinct troodontid. The differences between northern and southern faunas based on isolated theropod teeth provide evidence for provinciality in the late Campanian and the late Maastrichtian of North America. However, there is no indication that major components of small-bodied theropod diversity were lost during the Maastrichtian in New Mexico. The same pattern seen in northern faunas, which may provide evidence for an abrupt dinosaur extinction. 相似文献
14.
2011年4月~2012年5月,对新疆准噶尔盆地东南缘进行了4次鸟类调查,共发现鸟类10目25科40属54种.其中留鸟21种、夏候鸟23种、旅鸟6种、冬候鸟4种.国家Ⅰ级保护动物3种,为波斑鸨、白肩雕和金雕,国家Ⅱ级保护动物8种,为鹗、黑鸢、高山兀鹫、秃鹫、雀鹰、猎隼、红隼和蓑羽鹤.该地以角百灵和蒙古沙雀等荒漠鸟类为优势种,猛禽如棕尾鵟等也较常见. 相似文献
15.
The sand dunes of the Basin and Range Province of western North America contain obligate and endemic species of Coleoptera and Orthoptera. These dune habitats represent islands on which the isolated insular faunas are in a state of relaxation. The calculated temperature metric used in this study reflects the relative measure of disorder, by which the degree of nestedness can be determined. Sixteen dunes in the Basin and Range Province are shown to comprise a nested subset of obligate Coleoptera and Orthoptera. These sixteen sand dunes remain nested even when the endemic species are excluded from the analysis. The absence of endemic species slightly decreased the calculated temperature of the island-dune archipelago. Therefore, endemic species present in the sand dunes do not significantly contribute to the high degree of nestedness of dune obligate Coleoptera and Orthoptera in the Basin and Range Province. The dunes can also be separated into five distinct sub-basins, two of which contain only one sand dune. These sub-basins are not significantly nested, but together define the nested structure of the Basin and Range Province. 相似文献
16.
记述了江西省上高县发现的一窝不完整蛋窝的恐龙蛋。根据恐龙蛋宏观形态和蛋壳显微结构特征将其归入石嘴湾珊瑚蛋(Coralloidoolithus shizuiwanensis)。该窝恐龙蛋为近圆形球体,平均长径11.8 cm,平均赤道直径9.8 cm,蛋壳厚度可达2.5 mm;蛋壳由锥体层与柱状层组成,锥体层较薄,柱状层可分为内层、中间层和外层,内层发育致密的水平生长纹,中间层结构松散,含有大量暗色物质,中间层和外层发育次生壳单元。依据新标本的观察,明确珊瑚蛋属在石笋蛋科中以柱状层中间层结构松散为主要分类特征。上高新标本的发现,丰富了石嘴湾珊瑚蛋的古地理分布,同时也为上高地区晚白垩世含恐龙蛋红层的对比提供了新的证据。 相似文献
17.
Theropod footprints from the Jingshang tracksite in the Lower Cretaceous Dabeigou Formation of the Luanping Basin, Hebei Province, China, are re-evaluated after new discoveries at this locality. They occur in a succession with sandstone, mudstone, and calcareous shale. The depositional environment was a shallow lake shore, comparable in age to the famous Jehol Biota. Based on the distinct morphology with peculiar features of the ratio of the outer digits, the footprints formerly assigned to Changpeipus carbonicus are now referred to the new ichnogenus and combination Lockleypus luanpingensis. The possible trackmaker was a relatively large ornithomimosaurian theropod thus far not known from the skeletal record of the Jehol Biota. 相似文献
18.
《Palaeoworld》2016,25(3):425-430
Cretaceous evaporites of the Maha Sarakhan Formation in Thailand (e.g., the Nongbok Formation, Laos) have been studied for almost a century as the huge potash deposits in the world. The consistently high local paleotemperatures should lead to huge salt deposits during the evaporation process. Primary fluid inclusions in halite can provide surface brine water temperatures directly and quantitatively. Until now, there have been no data published from paleotemperature of primary fluid inclusions of Cretaceous halite. The non-marine halite from the Cretaceous Nongbok Formation (Laos) precipitated from shallow brine waters with temperatures of 17.7–42.3 °C. 相似文献
19.
The terpenoid compositions of the Late Cretaceous Xixia amber from Central China and the middle Miocene Zhangpu amber from Southeast China were analyzed by gas chromatography-mass spectrometry (GC-MS) to elucidate their botanical origins. The Xixia amber is characterized by sesquiterpenoids, abietane and phyllocladane type diterpenoids, but lacks phenolic abietanes and labdane derivatives. The molecular compositions indicate that the Xixia amber is most likely contributed by the conifer family Araucariaceae, which is today distributed primarily in the Southern Hemisphere, but widely occurred in the Northern Hemisphere during the Mesozoic according to paleobotanical evidence. The middle Miocene Zhangpu amber is characterized by amyrin and amyrone-based triterpenoids and cadalene-based sesquiterpenoids. It is considered derived from the tropical angiosperm family Dipterocarpaceae based on these compounds and the co-occurring fossil winged fruits of the family in Zhangpu. This provides new evidence for the occurrence of a dipterocarp forest in the middle Miocene of Southeast China. It is the first detailed biomarker study for amber from East Asia. 相似文献
20.
We report on the discovery of an Early Cretaceous bird from northwestern Gansu Province, in northwestern China. Represented by a nearly complete left wing and shoulder girdle the size of a rock dove, the new bird was quarried from laminated yellowish mudstones of the Xiagou Formation (Xinminpu Group) near Changma, in the Jiuquan area. These deposits have previously yielded the only known specimen of Gansus yumenensis, a basal ornithuromorph represented by the distal half of a hind limb with long and slender digits. Several derived characters of the new occurrence supports its allocation within Enantiornithes: (1) a convex lateral margin of the coracoid, (2) a minor metacarpal that projects distally more than the major metacarpal and (3) a proximal phalanx of the major digit longer than the intermediate (second) phalanx. The general proportions of the wing suggest it was a flier comparable to most other known enantiornithine birds. Although, direct comparisons between the new fossil and Gansus are not possible, phylogenetic based inferences supports their placement into two different clades. While the new fossil falls definitively within the enantiornithines, G. Yumenensis falls within the ornithuromorphs. The new occurrence thus adds to the taxonomic diversity of Early Cretaceous birds from Gansu Province in particular and central Asia in general. 相似文献