首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
记述了辽宁义县早白垩世九佛堂组的一件初鸟类(Avialae)化石,其嘴里无牙,前肢明显长于后肢,尾巴由20多节尾椎组成,叉骨呈U字形,飞行羽毛超过了身体的长度。各种特征表明,新发现的初鸟类真正具有了飞行能力,代表了恐龙向鸟类演化过程中的又一中间环节。正式将其命名为中华神州鸟(Shenzhouraptorsinensisgen.etsp.nov.)。  相似文献   

2.
This paper describes an avialian bird from the Early Cretaceous Jiufotang Formation in Yixian county, western Liaoning, China, which is named as Shenzhouraptor sinensis by Ji et al. on July 15, 2002. Shenzhouraptor sinensis is characterized by no teeth in its mouth, the forelimbs longer than the hindlimbs, a long tail with more than 23 caudal vertebrae, U-shaped wishbone, and remiges longer than the total length of ulna and manus. It is certain that the new avialian bird is really capable of powerful flight, representing a missing link between theropod dinosaurs and birds.  相似文献   

3.
The upper Campanian-lower Maastrichtian site of Lo Hueco (Cuenca, Spain) has provided a set of well-preserved partial skeletons in anatomical connection or with a low dispersion of their skeletal elements. One partial skeleton is herein described and a new titanosaurian sauropod is established, Lohuecotitan pandafilandi. This titanosaur is diagnosed by eight autapomorphic features: dorsally and ventrally widened or bifurcated posterior centrodiapophyseal lamina in anterior and middle dorsal vertebrae; short postspinal lamina with a transversely expanded distal end represented by smooth scars in the dorsal vertebrae; anteriormost caudals with the medial spinoprezygapophyseal and medial spinopostzygapophyseal laminae ventrally connected with the prespinal and postspinal laminae, respectively; anterior caudal neural spines with a dorsal projection of the prespinal and postspinal laminae; anterior caudal neural spines bears a “greek-cross”-like cross-section; middle caudal centra having two round and rough structures in the dorsal edge of the posterior articulation, which extends to the dorsal surface of the centrum; the articular ends of the rami of the haemal arches are divided in two articular surfaces; and tuberosity between the anterior and the lateral trochanter of the fibula. The herein performed phylogenetic analysis considered L. pandafilandi as a member of Lithostrotia more derived than Malawisaurus. The known palaeodiversity of the Late Cretaceous Ibero-Armorican titanosaurs is increasing, and further analyses focused on this group will be necessary to better understand the evolutionary history of European titanosaurs and to clarify their relationships within Titanosauria.  相似文献   

4.
吉林九台白垩系一新的蜥脚类恐龙   总被引:4,自引:0,他引:4  
记述了蜥脚类恐龙(Sauropoda)中一新的属种—西地九台龙(Jiutaisaurusxidiensisgen.etsp.nov.),包括18个相关节的尾椎及13个脉弧。化石产于吉林九台白垩纪泉头组的紫色-杂色砂岩中。其主要特征为:中部尾椎椎体两侧出现前后延长的棱脊,前-中部尾椎双凹型,神经弓位于椎体前半部,脉弧不分叉,血管孔长度约占脉弧长度的1/2以上。新属种的发现对进一步研究白垩纪蜥脚类恐龙的系统演化、古地理分布等提供了新的材料。  相似文献   

5.
Non-avian theropods are well represented in the Cretaceous of Asia. However, the first theropod remains ever reported from China, from the Wangshi Group of Shandong Province, have not been reassessed since they were described by Carl Wiman in 1929, despite the great strides that have been made in theropod phylogenetics in the last eight decades. The remains redescribed herein consist of four vertebrae (two cervicals, one dorsal and one caudal) from one site, and a caudal vertebra and ungual phalanx from another. The vertebrae from the first site are assigned to tyrannosauroids and ornithomimosaurs, as is the caudal vertebra from the second site, whereas the manual ungual also bears resemblances to those of non-maniraptoran coelurosaurs (specifically compsognathids and ornithomimosaurs). Theropods remain relatively rare in the Wangshi Group; nevertheless, the remains redescribed herein highlight the potential for the discovery of more theropod remains in future excavations.  相似文献   

6.
A new theropod dinosaur,Shidaisaurusjinae gen.et sp.nov.,has been described on the basis of an incomplete skeleton.The specimen was found near the base of the Upper Lufeng Formation(early Middle Jurassic)in Yunnan,China.It is the first theropod dinosaur from the Middle Jurassic of Yunnan.Shidaisaurus jinae is distinguishable from other Jurassic theropods by certain features from the braincase,axis,and pelvic girdle.The absence of any pleurocoels in the axis or in any anterior dorsal vertebrae suggests that the new Lufeng theropod is relatively primitive and more plesiomorphic than most of the Middle to Late Jurassic theropods from China.Most Chinese taxa of Jurassic theropod dinosaurs have not been well described;a further detailed study will be necessary for us to determine their phylogenetic relationships with Shidaisaurus jinae.  相似文献   

7.
The First Mesozoic Heterodactyl Bird from China   总被引:1,自引:1,他引:0  
1 Introduction Enantiornithines were the dominant birds nearly worldwide throughout the entire span of the Cretaceous (Chiappe, 1995; Feduccia, 1996). The adaptive radiation of opposite birds is little known besides the disparity of rostral morphology in Boluochia (Zhou, 1995), Longipteryx (Zhang et al., 2001), Longirostravis ( Hou et al., 2004), and the presence of stomach contents that reflect a diversity of diets. Like the structure of rostrum, differentiation of the locomotor apparatu…  相似文献   

8.
A new species of Darwinopterus, D. robustodens sp. nov. is described and named. Based on the new specimen, the diagnostic characters of Darwinopterus are amended and include: rostral dentition composed of well-spaced, spike-like teeth; the longest teeth are confined to the anterior half of the tooth row; tooth alveoli have raised margins; nasoantorbital fenestra confluent; inclined quadrate; elongate cervical vertebrae with low neural spine and reduced or absent ribs; long tail of more than 20 caudals partially enclosed by filiform extensions of the pre- and postzygapophyses; short metacarpus less than 60 per cent length of humerus, fifth toe with two elongate phalanges and curved second pedal phalanx of the fifth toe with the angle between the proximal and distal segments about 130 degrees. The complete specimen of the new pterosaur D. robustodens sp. nov. provides much more osteological information. The differences in tooth morphologies between Darwinopterus modularis and D. robustodens sp. nov. suggest that they filled different ecological niches. The hard integument-bearing Coleoptera may have been the main food source of Darwinopterus robustodens.  相似文献   

9.
A new species of Macrocnemus is described on the basis of two incomplete specimens from the Lower Ladinian Prosanto Formation of southeastern Switzerland. The new form can be distinguished by its gracile limb elements and having a noticeably longer tibia than either Macrocnemus bassanii or Macrocnemus fuyuanensis. One of the new specimens exhibits soft part preservation in the region of the pelvic girdle. The hind part of this individual is preserved fully articulated and allows a complete count of the caudal vertebrae to be made for the first time with 52 caudals. It is postulated that this specimen was predated upon and that the anterior part of the animal was consumed by a large predator such as a nothosaurid reptile or the actinopterygian fish Saurichthys.  相似文献   

10.
A new theropod dinosaur, Shidaisaurus jinae gen. et sp. nov., has been described on the basis of an incomplete skeleton. The specimen was found near the base of the Upper Lufeng Formation (early Middle Jurassic) in Yunnan, China. It is the first theropod dinosaur from the Middle Jurassic of Yunnan. Shidaisaurus jinae is distinguishable from other Jurassic theropods by certain features from the braincase, axis, and pelvic girdle. The absence of any pleurocoels in the axis or in any anterior dorsal vertebrae suggests that the new Lufeng theropod is relatively primitive and more plesiomorphic than most of the Middle to Late Jurassic theropods from China. Most Chinese taxa of Jurassic theropod dinosaurs have not been well described; a further detailed study will be necessary for us to determine their phylogenetic relationships with Shidaisaurus jinae.  相似文献   

11.
A New Titanosaurian Sauropod from Late Cretaceous of Nei Mongol, China   总被引:2,自引:0,他引:2  
A specimen collected from the Upper Cretaceous Erlian Formation of Nei Mongol (Inner Mongolia), China, represents a new genus and species of titanosaurian sauropod. The new taxon is named and described on the basis of the holotype and the only known specimen, which comprises several dorsal, sacral, and caudal vertebrae, several dorsal ribs, one anterior chevron, and much of the pelvis. Diagnostic features of the new species include a thick ridge extending down from the postzygapophysis on the lateral surface of the neural arch of the posterior dorsal vertebrae, a transversely oriented accessory lamina present between the anterior centroparapophyseal limina and the lateral centraprezygapophyseal lamina of the posterior dorsal vertebrae, long, anteroventrally directed caudal rib that bears two distinctive fossae on its posterior margin on the anterior caudal vertebrae and a prominent vertical ridge above the pubic peduncle on the medial surface of the ilium, among others. The ilium is pneumatic, a feature not common among non-avian dinosaurs. The new taxon has an unusual combination of primitive and derived character states. Preliminary character analysis shows a complex character distribution within the Titanosauriformes. Recent titanosauriform discoveries suggest that a significant radiation occurred in Asia early in the titanosauriform evolution.  相似文献   

12.
Jinfengopteryx is a newly uncovered Archaeopteryx-like avialan bird outside Germany, which was found from the Jehol Biota of northern Hebei in northeastern China. It shares many characters only with Archaeopteryx by the possession of three fenestrae in the antorbital cavity, 23 caudal vertebrae and long tail feathers attached to all the caudal vertebrae. But the former differs from the latter in the relatively short and high preorbital region of skull, more and closely packed teeth, much shorter forelimb compared to hindlimb. Such differences indicate Jinfengopteryx is even slightly more primitive than Archaeopteryx, although both birds can be placed at the root position of the avialan tree based on cladistic analysis. Shenzhouraptor is suggested to be slightly more advanced than Jinfengopteryx + Archaeopteryx, supported by some derived features in teeth, shoulder girdles and forelimbs such as the reduction of tooth number, dorsolaterally directed glenoid facet, very long forelimb and comparatively short manus. Meanwhile, the tail of Shenzhouraptor shows more primitive characters than those of Jinfengopteryx and Archaeopteryx, e.g., the strikingly longer tail composed of more caudal vertebrae and the long tail feathers attached only to distal caudal segments. The mixed primitive and advanced characters reveal the evident mosaic evolution among long-tailed avialan birds.  相似文献   

13.
A new large theropod, Orkoraptor burkei nov. gen. et nov. sp., from the Upper Cretaceous (Maastrichtian) Pari Aike Formation of southern Patagonia is based on a postorbital, quadratojugal, coronoid?, several teeth, an atlantal intercentrum and neurapophysis, two caudal vertebrae, and the proximal half of tibia. This new theropod exhibits characteristics of maniraptorans (i.e., coelurosaurians more derived than tyrannosaurids) including an upturned rostral process of the postorbital, the caudoventral corner of which is widely concave. Furthermore, teeth without denticles and carina in the mesial margin resemble the condition of the maniraptoran clades Compsognathidae and Deinonychosauria. The new Patagonian theropod differs from other coelurosaurians (Ornithomimosauria, Compsognathidae, Alvarezsauridae, Dromaeosauridae, Aves) in having caudal vertebrae with a single pair of small pleurocoels on each side, and in having a median depression flanked by two longitudinal and narrow furrows on each tooth. Orkoraptor represents one of the southernmost carnivorous dinosaurs yet found in South America and adds valuable information about the diversification of tetanuran theropods in Gondwana.  相似文献   

14.
本文描述了产于中国辽宁凌源早白垩世九佛堂组地层的一件鸟类化石标本。该标本中等大小,具有许多原始今鸟型鸟类的共同衍征;同时该标本也具有一个区别与其他已知原始今鸟型鸟类的长吻:吻长超过整个头骨长的70%;前颌骨前端尖而下钩,向前超出下颌前端,下颌齿骨前端直,仅上颌骨和齿骨上具有牙齿,代表了原始今鸟型鸟类一个新的属种和一个新的生态类型,因此建立了一个今鸟型鸟类新属种——张氏觉华鸟(Juehuaornis zhangi gen.et sp.nov)。  相似文献   

15.
中华神州鸟的发现及其科学意义   总被引:1,自引:0,他引:1       下载免费PDF全文
季强 《中国地质》2002,29(3):335-336
本文简要回顾了国际鸟类起源研究的历史,论述了中华神州鸟的发现在鸟类起源和早期演化研究中的科学意义,有力支持了鸟类的“兽脚类恐龙起源假说”和“陆地奔跑飞行起源假说”。  相似文献   

16.
李莉  王晶琦  侯世林 《世界地质》2010,29(2):183-187
记述了辽宁建昌头道营子早白垩世九佛堂组发现的孔子鸟化石一新种—建昌孔子鸟(Confuci-usornis jianchangensis sp.nov.)。尽管新种缺失前肢及肩带,还是在许多特征上很容易与属型种(圣贤孔子鸟)相区别。例如,个体小、鳞骨近三角形、方骨粗大、齿骨前端有突起、跗蹠骨近端愈合、第V跗蹠骨不存在和尾综骨粗大等。新种是孔子鸟类在建昌地区的首次发现,对于展示孔子鸟类的多样性等具有较重要意义。  相似文献   

17.
Naish  Darren 《Geologie en Mijnbouw》1999,78(3-4):367-373
A robust, partial right tibia of a theropod dinosaur (Natural History Museum London collections, BMNH R9385) is described for the first time. The specimen was collected at Hastings, Sussex (England) in the last century, and is among the oldest known of English Wealden Group theropods. It represents a tetanuran theropod that may have been about 3 m in total length, and is distinct from all currently known Wealden theropods for which tibiae have been described. The present specimen is significant palaeobiologically in exhibiting a series of theropod tooth marks on its caudal surface, indicating predation or scavenging by another theropod.  相似文献   

18.
A new titanosauriform sauropod Dongyangosaurus sinensis gen. et sp. nov. from the early Late Cretaceous of Dongyang County, Zhejiang Province, is erected based on a partial postcranial skeleton. It is characterized by complex laminae on the lateral surface of the neural spines and postzygapophyses of dorsal vertebrae, a distinct fossa on the ventral surfaces of the prezygapophyses of dorsal vertebrae, distinct fossae are also present on the lateral surface of the postzygapophysis of anterior caudal vertebrae; pubis is shorter than ischium, the small obturator foramen of pubis elongated, and nearly closed. The lamina complexity of dorsal vertebrae in Dongyangosaurus indicates that a higher diversity of titanosauriformes occurred during the early Late Cretaceous in China.  相似文献   

19.
Tail anatomy of unenlagiid theropods remains poorly known. The most complete and informative taxon of this family is Buitreraptor gonzalezorum from the Upper Cretaceous of Rio Negro province, Argentina. The aim of the present contribution is to carry out an analysis of the tail anatomy of Buitreraptor based on its holotype and a newly collected specimen as well. Similarities shared by Buitreraptor, Rahonavis, Anchiornis and Archaeopteryx include: mid-caudal vertebrae with postzygapophyses longer than prezygapophyses, and mid-caudal centra with a system of lateral laminae and concavities. Preservation of paravian skeletons, as well as muscular reconstruction, indicate the presence of two different functional sections of the tail. This contribution sheds light on paravian tail evolution and provides new data on tail changes that occurred along the theropod line towards modern birds.  相似文献   

20.
We herein describe an associated partial postcranial skeleton of a theropod dinosaur discovered in the Lower Cretaceous Xinminpu Group of the Yujingzi Basin, in the Jiuquan area of Gausu Province, northwestern China. Features of its humerus, such as strongly expanded proximal and distal ends, a well developed medial tuberosity, distal condyles expressed on the humeral cranial surface, and a hypertrophied entepicondyle, definitively establish the therizinosauroid affinities of the specimen. It differs from other therizinosauroids in having a shallow, poorly demarcated glenoid fossa with a prominent rounded and striated tumescence on the dorsomedial surface of its scapular portion, and a pubis with a strongly concave cranial margin. It represents a new taxon, Suzhousaurus megatherioides gen. et sp. nov. Cladistic analysis recovers Suzhousaurus as the sister taxon of Nothronychus mckinleyi from the mid-Cretaceous of western North America; together, they are basal members of the Therizinosauroidea, more derived than the Early Cretaceous Falcarius and Beipiaosaurus but less derived than Alxasaurus and the Therizinosauridae. Along with "Nanshiungosaurus" bohlini from possibly coeval beds in the Mazongshan area of northern-most Gansu, Suzhousaurus represents one of the largest-known Early Cretaceous therizinosauroids, demonstrating that this clade attained considerable body size early in its evolutionary history.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号