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1.
Two incomplete bones referred to ankylosaur scapulocoracoid and humerus are described, which were discovered from the Early Cretaceous Jiufotang Formation of Dachengzi Town, Kazuo County, Liaoning Province. Ankylosaur dinosaurs have ever been found in the Lower Cretaceous Yixian, Fuxin and Sunjiawan Formations of western Liaoning. The occurrence of ankylosaurs within Jiufotang Formation improves our knowledge on the ankylosaur stratigraphic distribution. Based on the length of scapulocoracoid, the new dinosaur is estimated to exceed 6.0 meters long, representing the largest ankylosaur in western Liaoning. 相似文献
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辽西下白垩统义县组湖相碳酸盐岩及其沉积环境研究 总被引:3,自引:0,他引:3
辽西地区下白垩统义县组是热河生物群产出的主要地层,其中产出大量精美的生物化石,但是由于受到后期构造破坏和风化作用影响,难以开展野外工作,热河生物群产出的古地理环境及盆地沉积环境的研究程度仍然较低。该组地层中湖相碳酸盐岩比较发育,本次工作主要对辽西义县组老公沟—金刚山剖面4个沉积层中产出的多层湖相碳酸盐岩沉积层进行了深入研究。通过野外工作结合室内镜下鉴定,分析了义县组湖相碳酸盐岩的产出状态和岩石类型,划分出5个岩相类型和两个相组合。结合野外实测剖面中碳酸盐岩与其它沉积岩层的组合关系对义县组湖相碳酸盐沉积环境进行了探讨,发现义县组湖相碳酸盐岩主要为洪水—漫湖沉积体系中较浅的储水洼地和滨浅湖半咸水沉积环境,并建立了义县组湖相碳酸盐岩沉积相模式。 相似文献
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A new Early Cretaceous enantiornithine bird from Liaoning Province of northeastern China, Shengjingornis yangi, gen. et sp. nov., is reported. This new bird possesses the following unique combination of features: a long rostrum, with some teeth in the front; short nasal; slender jugal; Y-shaped furcula, with expanded distal end of the hypocleidum; cake-like sternum, with a low and caudally distributed keel; strut-like and caudally concave coracoid. The derived features of the scapula and the wings suggest a powerful flapping flight capability. 相似文献
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A New Troodontid (Theropoda: Troodontidae) from the Lower Cretaceous Yixian Formation of Western Liaoning, China 总被引:2,自引:0,他引:2
XU Xing WANG XiaolinInstitute of Vertebrate Paleontology Paleoanthropology Chinese Academy of Sciences Beijing 《《地质学报》英文版》2004,78(1):22-26
A specimen collected from the Lower Cretaceous Yixian Formation of western Liaoning, China, represents a new genus and species of troodontid theropod. The new taxon is named and described on the basis of the holotype and the only known specimen, which comprises an articulated skeleton with the presacral vertebral, shoulder girdle and forelimbs missing as preserved. Diagnostic features of the new species include nasals that are sinusoid in lateral view, absence of a passage connecting the antorbital and maxillary fenestrae, relatively large teeth, plate-like chevrons forming a band along most of the length of the tail, and a long neck between the femoral head and shaft. The temporal constraints of the three paravian groups (Troodontidae, Dromaeosauridae and Aves) combined with the character distributions among the earliest known troodontids indicate a rapid evolution at the base of the Troodontidae. 相似文献
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SHEN Caizhi Lü Junchang LIU Sizhao Martin KUNDRáT Stephen L. BRUSATTE GAO Hailong 《《地质学报》英文版》2017,91(3):763-780
A new troodontid dinosaur,Daliansaurus liaoningensis gen.et sp.nov.,is erected based on a nearly complete specimen from the Lower Cretaceous Yixian Formation of Beipiao City,Liaoning Province,China.This well preserved skeleton provides important new details of the anatomy for Liaoning troodontids,and gives new insight into their phylogenetic relationships and evolution.Daliansaurus is distinguished from other troodontids by an enlarged ungual on pedal digit IV,which is approximately the same size as the sickle-shaped second ungual,and is differentiated from other Liaoning troodontids by a number of characters of the skull,manus,pelvis,and hindlimb.A phylogenetic analysis recovers Daliansaurus within a subclade of Liaoning troodontids that also includes Sinovenator,Sinusonasus,and Mei.We erect a name for this group—Sinovenatorinae—and argue that it reflects a localized radiation of small-bodied troodontids in the Early Cretaceous of eastern Asia,similar to previously recognized radiations of Liaoning dromaeosaurids and avialans.As more Liaoning theropods are discovered,it is becoming apparent that small,feathered paravians were particularly diverse during the Early Cretaceous,and future work is needed to clarify how this diversity arose,which species coexisted,and how these numerous species partitioned niches. 相似文献
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记述了辽宁省四合屯下白垩统义县组三个半恐龙足迹,归入似鹬龙足迹(亦译为跷脚龙足迹)一未定种(Grallator isp.)。这是义县组恐龙足迹化石的首次描述。该行迹至少由3个造迹者所造。从足迹推断恐龙体长1.51m,属于义县组兽脚类恐龙较为普遍的体长范围。重建了尾羽鸟(Caudipteryx)和中华龙鸟(Sinosauropteryx)的足部,前者的足迹轮廓与似鹬龙足迹未定种的吻合度超过后者。根据化石记录,似鹬龙足迹类型可能广泛存在于义县组的各种中小型兽脚类(驰龙类与伤齿龙类除外)中。 相似文献
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The abundant fossils of early angiosperms found in the Yixian Formation (125 Ma, Early Cretaceous) have demonstrated unexpectedly high diversity and various reproductive strategies, and thus have shed new light on early angiosperm evolution. Here, using light microscope and scanning electron microscope, we document several fructifications of Baicarpus gen. nov. from Liaoning province, China. Each fructification of the new taxon includes several apocarpous carpels/fruits attached in an urn-formed gynobase. Each fruit/carpel has a persistent straight style and an ovary enclosing a single seed. These fossil plants demonstrate a new floral organization and thus enhance our understanding of the diversity of angiosperms in the Yixian Formation. Together with previously reported ones, this fossil angiosperm suggests an origin time for angiosperms earlier than widely accepted. 相似文献
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Three eusauropod teeth (SDUST-V1064, PMOL-AD00176, PMOL-ADt0005) are reported from the Lower Cretaceous Yixian Formation of Ningcheng, southeastern Inner Mongolia, China. Two of them (SDUST-V1064, PMOL-AD00176) are assigned to early-diverging titanosauriforms in having slightly mesiodistal expansion at the base of the tooth crown, a slenderness index value >2.0 and <4.0, and D-shaped cross section. Furthermore, SDUST-V1064 and PMOL-AD00176 are referred as an Euhelopus-like titanosauriform on the basis of having a sub-circular boss on the lingual surface and an asymmetrical crown-root margin which slants apically, respectively. 相似文献
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记述了辽宁省四合屯下白垩统义县组三个半恐龙足迹,归入似鹬龙足迹(亦译为跷脚龙足迹)一未定种(Grallator isp.)。这是义县组恐龙足迹化石的首次描述。该行迹至少由3个造迹者所造。从足迹推断恐龙体长1.51m,属于义县组兽脚类恐龙较为普遍的体长范围。重建了尾羽鸟(Caudipteryx)和中华龙鸟(Sinosauropteryx)的足部,前者的足迹轮廓与似鹬龙足迹未定种的吻合度超过后者。根据化石记录,似鹬龙足迹类型可能广泛存在于义县组的各种中小型兽脚类(驰龙类与伤齿龙类除外)中。 相似文献
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新反鸟化石(Gracilornis jiufotangensis gen. et sp. nov.)产于辽宁省朝阳地区早白垩世九佛堂组。根据该反鸟的骨骼细弱、肢骨关节发达、胸骨与躯干相比较小(胸骨宽与躯干长比率约为0.11;胸骨长与躯干长比率约为0.13)等不同于其他已知反鸟的特征,建立一新属种,归于华夏鸟科(Cathayornithidae)。 相似文献
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辽宁锦州义县早白垩世义县组发现了一种新型燕鸟(Yanornis)化石.该新型化石具有燕鸟的典型特征,如齿骨直且约占头骨全长的2/3、每侧约含20枚牙齿,颈椎细长,异凹型.愈合荐椎包括9枚脊椎,前肢约为后肢长的1.1倍.近端脚趾较其它趾节长和粗壮.然而,该新型化石部分特征又不同于燕鸟的模式种——马氏燕鸟(Yanornis martini),如其肱骨三角肌脊强烈发育,约为肱骨长度的一半.尺骨、桡骨及手部近等长,均长于肱骨.耻骨联合部较短,与尾综骨等长,不到耻骨长度的1/6.腓骨较长,约为股骨长度的4/5,约为胫跗骨长度的2/3.跗跖骨较短并完全愈合,不及胫跗骨长度一半.根据该新型化石的独特性及其与义县鸟、松岭鸟和马氏燕鸟的特征对比,笔者建立了燕鸟一新种——国章燕鸟(Yanornis guozhangisp.nov.).此外,国章燕鸟(新种)颈部还保存有3条鱼化石,这一特殊现象为研究燕鸟的生活习性和发育模式提供了重要信息. 相似文献
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辽西义县组的地质时代 总被引:9,自引:0,他引:9
长期以来辽西义县组地质时代存在争论。通过对义县组命名地义县上底家沟—砖城子剖面义县组下部玄武岩的定年 ,获得K Ar年龄 131.2± 2 .6Ma ,坪年龄tp130 .4± 1.0Ma ,总气体年龄ttg130 .1± 1.3Ma ,等时年龄tI130 .5± 1.5Ma。这一结果表明 ,辽西义县组的地质时代应属早白垩世 ,其时代可与浙西劳村组、江苏宁芜盆地龙王山组、安徽庐枞盆地砖桥组对比。 相似文献
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A new species of tapejarid pterosaur, Huaxiapterus coroUatus sp. nov. is erected on the basis of a nearly complete skull and postcranial skeleton from the Lower Cretaceous Jiufotang Formation of Liaoning Province, China. Huaxiapterus coroUatus sp. nov. is characterized by a hatchet-shaped rectangular process on the premaxilla, whose short axis is perpendicular to the anterior margin of the premaxillae. Except for this process, other characters of the skull such as the breadth of the snout between the anterior margin of the nasoantorbital fenestra and the anterior margin of the premaxilla are similar to that of Huaxiapterus jii. Huaxiapterus and a second Chinese tapejarid, Sinopterus, share several unique cranial characters in common with Tapejara and these three genera appear to be more closely related to each other than to other azhdarchoids. The Chinese tapejarids (Sinopterus and Huaxiapterus) have relatively elongate skulls and weakly developed cranial crests and seem to be less derived than Tapejara, with its shorter, deeper skull and large cranial crest. Tupuxuarids (Tupuxuara and Thalassodromeus) have often been associated with tapejarids in the family Tapejaridae, but this relationship is controversial because some phylogenetic analyses have supported the pairing of tupuxuarids with Azhdarchidae. We propose that Tapejaridae be restricted to Tapejara, Sinopterus and Huaxiapterus. 相似文献
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WANG Xuri YOU Hailu MENG Qingjin GAO Chunling CHENG Xiaodong LIU Jinyuan 《《地质学报》英文版》2007,81(6):911-916
We herein describe a partial postcranial skeleton of a sauropod dinosaur recovered from the Lower Cretaceous Jehol Group in the Beipiao area of western Liaoning Province, northeastern China. A suite of features it possesses, including the camellate internal structure of its presacral elements, the existence of pneumatocoels on the proximal ends of the dorsal ribs, and especially the medially deflected proximal portion of the femur, definitively establish the titanosauriform affinities of the specimen. It differs from other titanosauriforms in having a craniocaudally elongate coracoid with a squared cranioventral extreme and a long, smooth, and slightly convex acetabular edge of the pubis. It represents a new taxon, Dongbeititan dongi gen. et sp. nov. Comparative studies suggest that Dongbeititan is a basal titanosauriform, more derived than Euhelopus, Fusuisaurus, and Huanghetitan, but less derived than Gobititan and Jiutaisaurus. Dongbeititan represents the first sauropod dinosaur reported from the Lower Cretaceous Jehol Group of western Liaoning Province. 相似文献
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根据新材料,对始无齿翼龙的特征进行了修订:中部颈椎体没有神经棘;肱骨三角嵴的长度与肱骨长度之比率约为0.2.5:翼掌骨的长度与第二翼指骨的长度几乎相等;第二翼指骨与第一翼指骨的长度之比率约为0.76。始无齿翼龙的新标本与正型稍微不同,可能由个体发育所引起。 相似文献
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Two new genera from the Lower Cretaceous Yixian Formation of Beipiao City, Liaoning Province, northeastern China are described and illustrated. Paracretocateres gen. nov. (type species P. bellus, sp. nov.) and Yixianteres gen. nov. (type species Y. beipiaoensis sp. nov.) are assigned to the subfamily Lophocaterinae based on the state of the procoxae which are not projecting, the transverse procoxal cavities, and the exposed protochantins. The new taxa broaden the diversity of this family and provide further morphological characters for phylogenetic studies of Trogossitidae. They also provide evidence that lophocaterines well-diversified prior to the trogossitines and their biologies may have been similar to extant forms. 相似文献