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1.
An almost complete juvenile dinosaur skull with lower jaw was discovered from the Early Cretaceous Yixian Formation in Beipiao, Liaoning Province, China. Here, the specimen is described and a cladistic analysis is performed in order to find its phylogenetic relationships. The result shows that this specimen represents a new genus of Psittacosauridae, Hongshanosaurus houi, gen. et sp. nov., and confirms the monophyletic status for Ceratopsia and Marginocephalia. However, Heterodontosaurus is found to be the sister taxon to Marginocephalia, rather than a basal Omithopoda.  相似文献   

2.
<正>We report on a new species of enantiornithine bird from the Lower Cretaceous Qiaotou Formation of northern Hebei,China.The new taxon,Shenqiornis mengi gen.et sp.nov.,possesses several enantiornithine synapomorphies but is unique from other known species.The specimen has a well-preserved skull that reveals new information about enantiornithine cranial morphology.The new taxon possesses a large postorbital with a long tapering jugal process indicating that some enantiornithines may have had a fully diapsid skull,as in Confuciusornis.The tooth morphology of the specimen is unique and likely represents a previously unknown trophic specialization within Enantiornithes.  相似文献   

3.
A new anurognathid pterosaur specimen from the Middle Jurassic Tiaojishan Formation of Qinglong, northern Hebie Province is described. The new specimen is referred to Dendrorhynchoides, based on the general morphology of the skeleton, but it represents a new species, named here as Dendrorhynchoides mutoudengensis sp. nov.. It is characterized by the presence of short, robust and straight teeth, and bearing wing metacarpal approximately 40% of the length of humerus. The new specimen provides further osteological information for anurognathid pterosaurs, especially the presence of a relatively elongate tail.  相似文献   

4.
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   

5.
<正>A new dinosaur Chuxiongosaurus lufengensis gen.et sp.nov.is erected based on a nearly complete skull.The taxon is characterized by the lacrimal perpendicular to the ventral margin of the upper jaw,which is similar to that of Thecodontosaurus;a depression present on the dorsal profile of the snout behind the naris;the rostral profile of the maxilla slopes continuously towards the rostral tip;and the presence of 25 dentary teeth.It also displays prosauropod characters such as a relatively long skull,the slope of the maxillary rostral profile,and teeth that do not have basically constricted crowns.The new specimen is more basal than Anchisaurus and represents the first basal sauropod dinosaur from the Early Jurassic of China.  相似文献   

6.
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   

7.
A new specimen of basal neoceratopsian dinosaur Liaoceratops yanzigouensis is described. The specimen comes from the Lujiatun Bed of the Lower Cretaceous Yixian Formation in Beipiao City of western Liaoning Province, and is represented by a very well preserved three-dimensional partial skull and mandible. It is also the smallest among the three specimens of L. yanzigouensis, and several features in the new specimen, such as the short preorbital length and the round rostroventral orbital rim, can be ontogenetically-related. The superb exposure of the palatal complex may be caused by the removing of its brain by a small predator in the contemporary Jehol Biota.  相似文献   

8.
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   

9.
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   

10.
<正>Recent discoveries of basal birds have greatly improved our understanding of early bird evolution,yet the evolution of several important features such as cranial kinesis and arboreality remain debated.A new sapeornithid bird,Shenshiornis primita gen.et sp.nov.,based on an articulated skeleton from the Early Cretaceous Jehol Group of western Liaoning,China,sheds new light on these issues.Shenshiornis possesses a skull as primitive as or even more primitive than that of Archaeopteryx and hind limbs modified for an improved arboreal capability.A cladistic analysis shows that:1) presence of a diapsid skull is a plesiomorphy of the Aves and a kinetic skull evolved incrementally later in avian evolution;and 2) cursorial capability significantly weakens at the base of the Pygostylia due to a change in locomotor system.  相似文献   

11.
系统描述了采自贵州省兴义中三叠统竹杆坡组一件较完整的巨胫龙(Macrocnemus)属化石标本,补充和完善了M.fuyuanensis部分头骨及腕骨和跗骨特征。基于当前标本与欧洲的M.bassaniis和中国的M.fuyuanensis的比较,认为当前标本与M.fuyuanensis四肢骨骼大小及比例较为接近,但两者的胫骨与桡骨、尤其第4跖骨和第4掌骨之间的比例不同。鉴于当前标本较少,头骨保存不完整,且当前标本与M.fuyuanensis正模标本的产地相距不远,本文暂将其确定为后者的相似种。  相似文献   

12.
We present a large, fragmentary skull and the humerus of a mosasaur (Squamata, Mosasauroidea) recovered from upper Maastrichtian beds of the López de Bertodano Formation in Marambio (=Seymour) Island, Antarctica. The material belongs to a large, adult individual with marked heterodonty as well as unusual humeral features. Different phylogenetic analyses returned the studied specimen within the Tylosaurinae, while the distinctive features of the skull and humerus allow distinguish it from the unique Antarctic known tylosaurine species, Taniwhasaurus antarcticus (Novas et al., 2002), as well as from other known Late Cretaceous mosasaurids from the Southern Hemisphere, thus, justifying the erection of a new taxon, Kaikaifilu hervei gen. et. sp. nov. The different dental types documented in the specimen studied have been previously recorded through isolated teeth from the same locality and were subsequently referred to several genera. This new find is relevant for assessing the previously known fragmentary records of Antarctic mosasaurids, suggesting that its local diversity could be more reduced than previously interpreted. The new material represents the youngest occurrence of tylosaurines in Antarctica.  相似文献   

13.
魏曌英  李莉 《世界地质》2017,36(3):655-662
描述发现于中国辽宁朝阳早白垩世九佛堂组地层中的一件鸟类标本。该标本体型较小,具有许多反鸟类的近裔特征。通过对新标本后肢形态特征的分析,可判断其为一小型树栖反鸟类。新标本具有发育的前肢和进步的乌喙骨,及发育滞后的后肢和相对原始的胸骨形态。胸骨长宽比约为1,顶端呈圆弧形,两个后侧突末端不膨大,中央突末端稍扩大,龙骨突基本不发育等。新标本同时具有反鸟类的原始和进步特征,以及原始的胸骨特征。其综合特征不同于已知任意一种小型反鸟类,因此建立一个反鸟类新属种——普通小反鸟(Microenantiornis vulgaris gen.et sp.nov.)。  相似文献   

14.
An incomplete dinosaur skeleton,including a partial skull,recently discovered from the Lower Jurassic Lufeng Formation of Yunnan,China,is here reported.Apart from its small size,little anatomical evidence supports,a priori,the non-adult status of this new sauropodomorph specimen but osteohistological analyses suggest that it is a fast-growing juvenile. This specimen represents only the second occurrence of a juvenile non-sauropodan sauropodomorph in the Lufeng Basin. The anatomy of the new specimen does not match that of other Lower Jurassic immature specimens;although cranial material is preserved,it does not display the diagnostic characters of early sauropodomorphs from the same horizon,namely Lufengosaurus,Yizhousaurus and Yunnanosaurus.Our phylogenetic analysis places the new specimen in a position relatively distant from other Chinese sauropodomorphs,and corroborates the anatomical evidence showing it is not referable to any known species already excavated in Yunnan.This result is interpreted with caution considering that ontogeny affects phylogenetic reconstruction.A thorough comparison with adult forms,taking into account ontogeny-related characters,suggests that this Lufeng juvenile might represent a previously unknown species of early sauropodomorph.  相似文献   

15.
《China Geology》2018,1(1):28-35
An alvarezsaurid dinosaur skeleton was discovered from the Late Cretaceous Qiupa Formation of Luanchuan, Henan Province of central China. It represents a new alvarezsaurid dinosaur Qiupanykus zhangi gen. et sp. nov. A phylogenetic analysis recovers Qiupanykus nested within the unresolved clade, which includes Asian and north American taxa. The skeleton of the new specimen is preserved in association with eggshells. The eggshell morphologies show that these eggs belong to oviraptorid eggs, skeletal remains of which were discovered from the same area. The alvarezsaurid skeleton associated with eggshell fragments may indicate that these eggs were broken by the strong thumb-claws of the former and that alvarezsaurid dinosaurs may be egg-eaters.  相似文献   

16.
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   

17.
辽西凌源全身长有羽毛奔龙化石的再研究   总被引:8,自引:0,他引:8  
对辽西凌源发现的全身长有羽毛的奔龙化石 (NGMC91) (Ji等 ,2 0 0 1)进行了再研究。根据头颅和头后骨骼的特征 ,其应归于中国鸟龙属 (SinornithosaurusXuetal.,1999)。由于研究的材料是一块处于非成年期的标本 ,虽然其有些特征明显与千禧中国鸟龙有别 ,但仍难以确定这些差异是否受个体发育的影响。因此 ,文中仍将其作为未定种 ,置于中国鸟龙属中。此外 ,文章还简要讨论了羽毛的发生和早期演化 ,认为羽毛出现的初始功能就是为了保持体温 ,与后期的飞行功能无关  相似文献   

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