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1.
A New Basal Neoceratopsian Dinosaur from the Middle Cretaceous of Jilin Province,China 总被引：1，自引：0，他引：1
A new basal neoceratopsian dinosaur, Helioceratops brachygnathus gen. et sp. nov., is described from the Quantou Formation (late Early Cretaceous or early Late Cretaceous) in the Liufangzi locality (Jilin province, China). Helioceratops differs from other basal neoceratopsians with its deep dentary ramus, its steeply-inclined ventral predentary facet, its heterogeneous dentary crowns, and by the denticles and secondary ridges asymmetrically distributed on either side of the primary ridge on its dentary teeth. Along with Auroraceratops and Yamaceratops, Helioceratops represents one of the most derived non-coronosaurian neoceratopsians. The palaeogeographical distribution of basal neoceratopsians appears limited to northern China and southern Mongolia in the current state of our knowledge. It is therefore probable that this region constituted the birthplace for more advanced, Late Cretaceous Coronosauria. 相似文献
2.
On a New Genus of Basal Neoceratopsian Dinosaur from the Early Cretaceous of Gansu Province, China 总被引：1，自引：3，他引：1
1 Introduction The Mazongshan area in northwestern China yields a diverse dinosaur assemblage, including members of Theropoda, Sauropoda, Ankylosauridae, Euornithopoda, and Ceratopsia (Dong, 1997; You, 2002). This assemblage is characterized by several well-established taxa, such as the basal neoceratopsian Archaeoceratops oshimai (Dong and Azuma, 1997; You and Dodson, 2003), the basal hadrosauroid Equijubus normani (You et al., 2003a), and the basal titanosaurian Gobititan shenzhouensi… 相似文献
3.
中国甘肃省酒泉地区公婆泉盆地早白垩世恐龙化石 总被引：2，自引：0，他引：2
中国甘肃省酒泉地区公婆泉盆地下白垩统新民堡群的恐龙化石主要由1992年中日丝绸之路恐龙考察计划和1997~2000年中美马鬃山恐龙考察计划发掘和研究。先后发现的恐龙包括兽脚类、蜥脚类、禽龙类和新角龙类等。这一新的公婆泉恐龙组合的主要特征是同时包含了在晚白垩世占主导地位的几类恐龙的基干分子,如戈壁巨龙(Gobititan)是巨龙型类的基干分子,马鬃龙(Equijubus)是鸭嘴龙型类的基干分子,而古角龙(Archaeoceratops)和黎明角龙(Auroraceratops)是新角龙类的基干分子。公婆泉恐龙组合的另一特征是其某些成员的体型较大,如似鸟龙类和镰刀龙类恐龙是同期同类中最大的。比较研究发现,公婆泉盆地新民堡群的恐龙和辽西热河群的恐龙关系密切,但前者的整体来说要比后者进步。考虑到公婆泉盆地新民堡群的时代(Albian)较辽西热河群(Hauterivian晚期-Aptian早期)晚,公婆泉恐龙组合似应代表中国北方早白垩纪鹦鹉嘴龙恐龙动物群进化过程中较进步的一个阶段。 相似文献
4.
A new basal hadrosauriform dinosaur, Xuwulong yueluni gen. et sp. nov., is reported based on an articulated specimen including a complete cranium, almost complete axial skeleton, and complete left pelvic girdle. The specimen is recovered from the Early Cretaceous Yujingzi Basin in the Jiuquan area, Gansu Province of northwestern China. Xuwulong is among the most basal members of hadrosauriform dinosaurs, and distinguished by its unique lower jaw in having a V-shaped rostral end of the dentary in lateral view and a mandibular articular surface which levels with mid-height of the dentary ramus, as well as an enlarged and downturned prepubic process. Including Xuwulong, three basal hadrosauriforms have been discovered from the Early Cretaceous Xinminpu Group in the Mazongshan area, making it an important area to study the origin and early evolution of duck-billed dinosaurs. 相似文献
5.
Casanovas M.L. Pereda Suberbiola X. Santafé J.V. Weishampel D.B. 《Geologie en Mijnbouw》1999,78(3-4):345-356
New hadrosaurid material is recorded from Fontllonga (Ager syncline, province of Lleida), in the Catalonian Pyrenees, comprising a dentary with part of the dental battery, recovered from Late Maastrichtian strata (Tremp Formation), close to the presumed Cretaceous/Tertiary boundary. This hadrosaurid is more derived than is Telmatosaurus transsylvanicus from the Haeg Basin (Romania), but lacks a number of features that diagnose the clade Hadrosaurinae plus Lambeosaurinae. It is attributed to the Euhadrosauria on the basis of the following synapomorphies: dentary teeth not recurved distally, narrow dentary crowns, and denticles not supported by subsidiary ridges. The phylogenetic relationships of the best-known iguanodontids and hadrosauroids are evaluated using mandibular and dentary tooth characters. On the basis of a cladistic analysis, the family of Hadrosauridae is diagnosed by more than 29 dentary tooth positions, parallel-sided vertical furrows formed by dentary alveoli, and absence of caudal secondary ridges. Within Hadrosauridae, successive sister-groups of Hadrosaurinae plus Lambeosaurinae are the Fontllonga taxon and Telmatosaurus. The clade Hadrosaurinae plus Lambeosaurinae is characterised mainly by a coronoid process inclined rostrally and by the absence of secondary ridges on dentary crowns. The Fontllonga find suggests the diversity of European hadrosaurids at the end of the Cretaceous to have been greater than previously thought. Moreover, the primitive character of European hadrosaurids as compared to western North American and Asian relatives may be explained in terms of geographical isolation during the Late Cretaceous. 相似文献
6.
MO Jinyou ZHAO Zhongru WANG Wei XU Xing 《《地质学报》英文版》2007,81(4):550-554
A new hadrosaurid dinosaur,Nanningosaurus dashiensis gen.et sp.nov.,is described based on an incomplete skeleton from the Late Cretaceous red beds of the Nalong Basin,Guangxi,southern China.Diagnostic features for the new taxon include the presence of a tall and sharply peaked dorsal process of the maxilla with reduced process of the jugai and a distinct lacrimal facet,gracile humerus with low,rounded deltopectoral crest,mandibular condyle of the quadrate transversly broad with reduced paraquadrate notch,dentary tooth with sinuous median carina and subsidiary ridge,relatively few tooth positions,ischial shaft straight along most of its distance,but to curve dorsally and expand at the distal end before the ischial foot begins.Phylogenetic analysis suggests that Nanningosaurus dashiensis is a basal member of Lambeosanrinae. 相似文献
7.
Ceratopsians were herbivorous dinosaurs that dominated many of the terrestrial ecosystems in Asia and North America during the Cretaceous. The bizarre variety of skulls and lower jaw morphologies as well as the inferred ecological abundance of many species in this clade indicate that Ceratopsia was a successful group. Here we analyzed 126 lower jaws from 50 ceratopsian species, using two-dimensional geometric morphometrics and finite element analysis to investigate differences in shape and structural performance of this part of the feeding apparatus across Ceratopsia. Morphological differences in lower jaws across ceratopsian clades are said to originate from feeding adaptation.Our results show that the stress (physical loadings modeled in response to biting) in lower jaws was quite similar between “basal” and “derived” taxa, whereas major differences among clades occur for stress values associated with the coronoid process. The basal ceratopsians Hualianceratops and Yinlong had a highly stressed and primitive lower jaw, indicating that those animals may have fed on relatively soft foliage and fruits. A similar condition was found for basal neoceratopsians and protoceratopsids. Psittacosaurids possessed a well-integrated and compact lower jaw able to withstand high stress, at the cost of having a highly stressed coronoid process. Leptoceratopsids were characterized by the opposite condition. Taxa such as Leptoceratops, Prenoceratops, Zhuchengceratops and Cerasinops appear to have had a comparatively efficient feeding apparatus. Ceratopsidae represents the clade with the most efficient masticatory apparatus within Ceratopsia, even if the horizontal ramus of the lower jaw appears less able to withstand high levels of stress as compared with other ceratopsians. Additionally, we found the dentary and surangular–angular complex co-evolved to generate a masticatory apparatus able to withstand high stress, particularly in Protoceratopsidae and Triceratopsini. The major phenotypic evolutionary rate and morphological changes occurred during the mid- to Late Cretaceous, when intense climate change and angiosperm diversification could have affected the evolution of ecological diversity and feeding biomechanics in Ceratopsia. 相似文献
8.
本文描述了产自中国辽宁省北票市早白垩世义县组一新的伤齿龙类化石——柯氏辽宁猎龙(Liaoningvenator curriei gen. et sp. nov.)。它具有伤齿龙类以下特征: 数量众多且密集的上颌齿与下颌齿; 牙齿的齿冠与齿根之间显著收缩; 齿骨侧表面具有一沟, 营养孔位于该沟内; 远端尾椎背部的神经棘减弱为一个沟。它不同于其它伤齿龙类的特征主要为坐骨靴大, 侧面观近乎三角形, 坐骨闭孔突细长; 尾椎形态转变点位于第7尾椎。系统发育分析表明柯氏辽宁猎龙与短羽始中国羽龙(Eosinopteryx brevipenna)构成姊妹群, 位于同一分支内。它们具有如下共同特征: (1)上颌骨和下颌骨前面部分的牙齿前隆无锯齿; (2)颈肋较其相关节的椎体长; (3)肠骨前缘直。辽宁猎龙代表了辽西同等层位发现的第5个伤齿龙类。骨组织研究显示辽宁猎龙的骨骼已接近成熟, 死亡时至少4岁。它为该地区的基干伤齿龙类恐龙提供了新的解剖学信息, 并丰富了目前中国已知早白垩世伤齿龙类的多样性。 相似文献
9.
《China Geology》2020,3(1):1-7
A new dsungaripterid pterosaur, Ordosipterus planignathus gen. et sp. nov., is established on the incomplete articulated lower jaws from the Lower Cretaceous Luohandong Formation in Otog Qi, Ordos Region, Inner Mongolia, China. It differs from other dsungaripterids mainly by having broad and low dentary at and just behind the mandibular symphysis, flat dentary dorsal plane forming the distinct lateral ridge with the curved dentary lateral side, and lower alveoli arranged along the dentary dorsolateral margin with wide spacing that increases from rostral to caudal. It represents the first diagnostic pterosaur from the Ordos Region in Inner Mongolia, and further enlarges the geographical distribution of the family Dsungaripteridae from northwestern China (together with western Mongolia) to central North China. 相似文献
10.
A nearly complete right maxillary or left dentary tooth（NHMG 10858） from the Lower Cretaceous Xinlong Formation of the Napai Basin, Fusui County, Guangxi, southern China, is described. The tooth is large in size, with a CBL of 37 mm. Given the geological age and its crown morphology, including the size, it is most likely that the tooth belongs to a carcharodontosaurid. The recovered specimen represents one of the largest theropod teeth hitherto reported from the Early Cretaceous of Asia. 相似文献
11.
鸭嘴龙科(Hadrosauridae)化石根据头骨特征等被划分为鸭嘴龙亚科(Hadrosaurinae,无头冠)和赖氏龙亚科(Lambeosaurinae,有头冠)。黑龙江嘉荫龙骨山晚白垩世渔亮子组保存了丰富的鸭嘴龙化石,其中黑龙江满洲龙Mandschurosaurus amurensis(Riabinin,1925)是最早在中国发现的恐龙,属鸭嘴龙亚科;嘉荫卡龙Charonosaurus jiayinensis(Godefroit et al,2000)也是在这里发现的,属赖氏龙亚科。本文描述了采自嘉荫龙骨山的部分左齿骨化石和一些牙齿化石,新的化石明显属于鸭嘴龙亚科,主要特征为:齿骨每个牙列有5个以上的牙齿,牙冠边缘小锯齿由乳头状小瘤构成。新发现的牙齿牙冠上发育有明显的第二、三副脊,这在鸭嘴龙中是罕见的。新发现的化石明显不同于产于同一地点的嘉荫卡龙,但由于黑龙江满洲龙模式标本没有保存牙齿,因此暂不能与之充分对比。 相似文献
12.
YOUHailu ЛQiang LIJinalu LIYinxian 《《地质学报》英文版》2003,77(2):148-154
A new hadrosauroid dinosaur,Shuangmiaosaurus gilmorei gen.et sp.nov,is descuibed based on a complete left maxilla with articulated premaxilla and lacrimal fragments,and a complete left dentary from the mid-Cretaceous Sunjiawan Formation of Beipiao.Liaoning,northeastern China.Chadistic analysis shows that Shuangmiaosaurus is a basal hadrosauroid,and comprises the sister taxon to Hadrosauridae.In both Shuangmiaosqurus and Hadrosaurids.However,Shuangmiaosaurus does not possess such hadrosaurid synapomorphies as the diamond-shaped maxillary crowns with reduced primary ridges and reduced marginal denticles. 相似文献
13.
Tyrannosaurs and hadrosaurs from the Late Cretaceous of eastern North America (Appalachia) are distinct from those found in western North America (Laramidia), suggesting that eastern North America was isolated during the Late Cretaceous. However, the Late Cretaceous fauna of Appalachia remains poorly known. Here, a partial maxilla from the Campanian Tar Heel Formation (Black Creek Group) of North Carolina is shown to represent the first ceratopsian from the Late Cretaceous of eastern North America. The specimen has short alveolar slots, a ventrally projected toothrow, a long dentigerous process overlapped by the ectopterygoid, and a toothrow that curves laterally, a combination of characters unique to the Leptoceratopsidae. The maxilla has a uniquely long, slender and downcurved posterior dentigerous process, suggesting a specialized feeding strategy. The presence of a highly specialized ceratopsian in eastern North America supports the hypothesis that Appalachia underwent an extended period of isolation during the Late Cretaceous, leading the evolution of a distinct dinosaur fauna dominated by basal tyrannosauroids, basal hadrosaurs, ornithimimosaurs, nodosaurs, and leptoceratopsids. Appalachian vertebrate communities are most similar to those of Laramidia. However some taxa-including leptoceratopsids-are also shared with western Europe, raising the possibility of a Late Cretaceous dispersal route connecting Appalachia and Europe. 相似文献
14.
A new specimen of ankylosaurine dinosaur Crichtonpelta benxiensis is described. The new specimen is based on a nearly completely preserved skull from the same quarry as the holotype of the mid-Cretaceous Sunjiawan Formation in Shuangmiao, Beipiao City, Liaoning Province, China. Cladistic analysis incorporating new information from the new specimen resolves Crichtonpelta benxiensis is more advanced than basal members of Ankylosauridae (Kunbarrasaurus, Liaoningosaurus, Chuanqilong, Cedarpelta, Gobisaurus and Shamosaurus) and represents the first diverging branch of Ankylosaurinae. Comparisons to other mid-Cretaceous ankylosaurid-bearing dinosaur assemblages in northern China indicate a late Early Cretaceous to early Late Cretaceous age for the Shuangmiao dinosaur assemblage. 相似文献
15.
《煤田地质与勘探》2021,49(5):190-199
The Cretaceous is a typical period for studying the greenhouse climate and the earth system interactions, and the world's most extensive terrestrial strata are mainly in East Asia, especially in China. Continental sediments can effectively reflect the paleo-climate change, but the previous studies of the Late Cretaceous paleo-climate, based on the combined characteristics of continental climate-sensitive sediments, were barely found in China. To obtain the Late Cretaceous paleo-climate characteristics of China, the distribution characteristics of different continental climate-sensitive sediment types in the early, middle and Late Cretaceous in China were studied in detail. According to the distribution and combination characteristics and types of continental climate-sensitive sediments, seven climate types can be divided: 1) warm-humid and warm-dry climate; 2) hot and dry climate; 3) hot-dry and arid climate; 4) hot-dry and semiarid climate; 5) hot-dry and hot-wet climate; 6) hot-dry and warm-humid climate; 7) hot-dry and warm-dry climate. The results show that in the early Late Cretaceous, the hot and dry climate was the most widespread, followed by warm-humid and warm-dry climate, but the climate was drier than the paleo-climate of the previous study of Early Cretaceous. Hot and dry climate zone became wider in the Coniacian and Maastrichtian; furthermore, it covered Xinjiang to the east of China from east to west after the Santonian Period. The hot-dry and semiarid climate zone was nearly latitudinally distributed from the northwest to the southeast and it shows a further increase in aridification. Global geological events, paleogeographic features and regional tectonic evolution had significant impacts on the paleoclimate of China in the Late Cretaceous, such as global eruptive events of volcanoes led to the temperature increase in China in the early Late Cretaceous; coastal mountain ranges in southeastern China led to the drying of the Late Cretaceous climate in southern China; Xuefeng Mountains, Wuling Mountains, Nanling Mountains and Tai-hang Mountains were the dividing line between the hot and dry climate zone and hot-dry and arid climate zone in the early Late Cretaceous, and Altun Mountains were the dividing line between the southeastern section of the hot and dry climate zone in western China in the middle Late Cretaceous. 相似文献
16.
中国白垩纪叶肢介生物地层学 总被引：3，自引：0，他引：3
叶肢介是一种淡水甲壳类动物,个体不大,一般在几毫米到两厘米之间,软体有点像虾,具有很多附肢,雌雄异体,外裹一对几丁质壳瓣,形似蚌壳,但不如后者的钙质壳那么厚实坚硬。叶肢介从泥盆纪开始出现,中生代时其演化中心从欧洲迁移到了东亚,白垩纪它们的分异和演化达到顶峰,到了新生代则进入衰亡阶段。叶肢介化石一般出现在陆相地层中,由于它数量多、演化快、分布广泛,近年来已成为中国和邻近地区中生代非海相生物地层划分和对比研究的重要手段之一。中国大陆白垩系主要是陆相沉积,按古地理和生物地理区系,早白垩世可以划分为西南湖群和东北、东南、西北两个大区,前者出现的是直线叶肢介(Orthestheria)动物群,后者则是东方叶肢介(Eosestheria)和延吉叶肢介(Yanjiestheria)动物群;晚白垩世在西南湖群出现的是华美叶肢介(Aglestheria)动物群,在东北松花湖水系出现的是真瘤模叶肢介(Euestherites)动物群,在华中和东南沿海云梦泽水系出现的是薄壳叶肢介(Tenuestheria)动物群。链叶肢介(Halysestheria)是联系它们相互对比的共同分子;晚白垩世早期的线叶肢介(Nemestheria)动物群则在上述3个区系都有分布,甚至在西北喀什地区的塞诺曼期海陆交互相沉积和美国德克萨斯州同期海相地层的陆相夹层中都有发现的记录,它是将中国陆相白垩系与国际海相标准划分联系起来的重要证据。关于中国白垩纪的叶肢介动物群和有关陆相地层的划分对比,产东方叶肢介的义县组以前放在上侏罗统顶部或做为侏罗系-白垩系过渡层处理,这次按全国地层表将东方叶肢介群归入早白垩世。 相似文献
17.
During the latest Cretaceous, distinct dinosaur faunas were found in Laurasia and Gondwana. Tyrannosaurids, hadrosaurids, and ceratopsians dominated in North America and Asia, while abelisaurids and titanosaurians dominated in South America, India, and Madagascar. Little is known about dinosaur faunas from the latest Cretaceous of Africa, however. Here, a new abelisaurid theropod, Chenanisaurus barbaricus, is described from the upper Maastrichtian phosphates of the Ouled Abdoun Basin in Morocco, North Africa on the basis of a partial dentary and isolated teeth. Chenanisaurus is both one of the largest abelisaurids, and one of the youngest known African dinosaurs. Along with previously reported titanosaurian remains, Chenanisaurus documents the persistence of a classic Gondwanan abelisaurid-titanosaurian fauna in mainland Africa until just prior to the end-Cretaceous mass extinction. The animal is unusual both in terms of its large size and the unusually short and robust jaw. Although it resembles South American carnotaurines in having a deep, bowed mandible, phylogenetic analysis suggests that Chenanisaurus may represent a lineage of abelisaurids that is distinct from those previously described from the latest Cretaceous of South America, Indo-Madagascar, and Europe, consistent with the hypothesis that the fragmentation of Gondwana led to the evolution of endemic dinosaur faunas during the Late Cretaceous. 相似文献
18.
To date three taxa of troodontid theropod dinosaurs have been recognized from Upper Cretaceous strata in two regions of the Kyzylkum Desert in Uzbekistan. The Cenomanian Khodzhakul Formation in the southwestern Kyzylkum Desert has yielded isolated serrated teeth and some postcranial bones of an indeterminate troodontid. In the central Kyzylkum Desert troodontids are known from the Cenomanian Dzharakuduk Formation (Urbacodon itemirensis) and the Turonian Bissekty Formation (Urbacodon sp.). Urbacodon itemirensis is known from a single dentary whereas Urbacodon sp. is represented by isolated teeth, maxilla and dentary fragments, a partial braincase, and some postcranial bones. The troodontid affinities of Urbacodon are supported by several synapomorphies: presence of a subotic recess; reduced basal tubera placed directly under the occipital condyle; maxilla participating in the margin of the external naris; nutrient foramina on dentary situated within a deep lateral groove; dentary without distinct interdental plates; large number of small dentary and maxillary teeth; teeth constricted between root and crown; anterior dentary teeth smaller, more numerous, more closely spaced than those in the middle of the tooth row, and implanted in a groove; posterior dorsal vertebrae with tall and posterodorsally tapering neural spines; and presence of a midline sulcus on the neural arches of distal caudals. Among Troodontidae, Urbacodon resembles Byronosaurus, Gobivenator, and Xixiasaurus in the absence of serrations on the tooth crowns and having premaxillary teeth that are D-shaped in cross-section. However, phylogenetic analysis did not recover a clade of Asiatic troodontids with unserrated teeth. 相似文献
19.
晚白垩世河道和冲积平原等河流相沉积广泛分布于中国大部分地区,保存了大量以鸭嘴龙超科为主的恐龙骨骼化石和遗迹化石。这些河流是否存在水系上的联系以及其对陆地生态系统分布的影响程度,目前研究较少。笔者收集了中国9个晚白垩世陆相盆地共2357个碎屑锆石的U-Pb年龄资料,通过对已收集的碎屑锆石的物源分析,探讨了中国晚白垩世的水系展布模式和物源方向。研究结果表明:晚白垩世中国南方地区可能存在北东—南西向的大型水系,其与现代水系展布模式相反,整体流向可能起源于晚中生代东部高原,向西和西南方向流经中国南方大部分地区,并形成了彼此相互交错、宽阔的河岸和冲积平原带;而北方地区的盆地则显示出被古隆起分隔的山间盆地特征,除共享来自晚中生代东部高原的少量物源外,各个盆地的物源主要来自于周围的古隆起,并形成了较为独立的复杂水系。以鸭嘴龙超科为代表的恐龙主要繁盛于北方地区相对独立的水系所形成的流域,演化出独特的东亚鸭嘴龙超科动物群。南方大型水系所形成的流域虽然保存了大量恐龙蛋和足迹化石,但仅发现少量骨骼化石,推测这可能是因为以鸭嘴龙为主的恐龙不适宜在南方炎热干旱的气候条件下常年生活,而只是在适宜的季节沿南方大型水系迁徙或繁殖。 相似文献
20.
皖南屯溪地区石岭组流纹岩LA-ICP-MS锆石U-Pb年龄及其时代的重新厘定 总被引：1，自引：0，他引：1
皖南屯溪地区位于江南新元古代造山带东段,发育少量中生代燕山期石岭组流纹岩、凝灰岩等火山岩。因一直缺乏精确的测年数据,以往研究者根据屯溪地区1∶5万区域地质调查获得的石岭组火山岩全岩K-Ar年龄值115~139 Ma,将其形成时代定为晚侏罗世—早白垩世。由于2004年前后国际地质年代表将侏罗纪与白垩纪界线由135 Ma提前到145 Ma,石岭组火山岩的形成时代便由原来的晚侏罗世—早白垩世更改为早白垩世。在屯溪东面尤溪村石岭组流纹岩中首次获得精确的LAICP-MS锆石U-Pb年龄154.7±2.5Ma,早于145Ma,表明屯溪地区石岭组火山岩形成于晚侏罗世而不是早白垩世。这一发现对构建皖南乃至中国东南部晚中生代构造演化模型具有参考意义。 相似文献