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1.
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   

2.
From a newly discovered Early Cretaceous fossil site at the Sanlianhe Coal Mine in Tahe County, Heilongjiang Province, the most northern area in China, two freshwater fossil fish had been recovered. This paper reports their classifications and implications regarding the palaeobiogeography of the Jehol Biota. The fish assemblage consists of Yanosteus sp. (Acipenseriforms) and Sinamia sp. (Amiiformes). Both are important members of the well known Jehol Biota, and their occurrence supports the correlation of the Yiliekede Formation at Sanlianhe Coal Mine site with the Jiufotang Formation of West Liaoning. The remains of the Yanosteus sp. from this locality is the first known record of the genus other than in the Yan‐Liao area of China, and the specimens of Sinamia sp. is quite similar to what may be a new species of Sinamia from West Liaoning. The new fossil site represents the most northern site that is undoubtedly part of the extent of the Jehol Biota as currently understood. The northern Great Xing'an Range area is an important region that may link correlations between the Early Cretaceous continental biotas of China, Mongolia and Russia. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

3.
Three new species, Lebanoculicoides excantabris, Archiaustroconops borkenti, and Atriculicoides szadziewskii are described from the Early Cretaceous (early Albian) El Soplao amber deposit (Rábago, Cantabria, northern Spain). Protoculicoides skalskii Szadziewski and Arillo, found in the other Albian Spanish ambers from Peñacerrada I (in Burgos) and San Just (in Teruel), and Austroconops sp., are identified from this new outcrop. The find of a new species of Lebanoculicoides Szadziewski is especially significant since this genus is considered the basalmost known among ceratopogonids. To date, the new species of Atriculicoides Remm is the oldest occurrence for this genus. A general review of the taxonomy and phylogeny of the family Ceratopogonidae, and the palaeoecological significance and palaeogeographic distribution of its basalmost lineages are given. The new data extend knowledge about biting midges during the Early Cretaceous, a key period for understanding the phylogenetic relationships of the ancient members of the family.  相似文献   

4.
We describe a new species of Early Cretaceous bird from the Yixian Formation of Liaoning Province. Xinghaiornis lini gen. et sp. nov. is relatively large and characterized by a long, toothless rostrum and an elevated pedal digit I. The design of the skull and feet suggests that this bird was likely a mud-prober. This discovery provides strong support indicating that this avian trophic specialization originated at least 125 million years ago.  相似文献   

5.
张伟  高克勤 《古地理学报》2014,16(2):205-216
离龙类是一在形态和生态适应上高度特化的水生—半水生爬行动物双孔亚纲的灭绝支系。离龙目的地理分布局限于北半球,地史分布从侏罗纪一直延续到中新世。辽西是中国最为重要的离龙类化石产地,化石点主要分布于凌源、义县、朝阳和建昌4个地区,尤其以义县地区化石点的分布最为密集。目前辽西已经发现的离龙类包括3科4属5种,其中潜龙和满洲鳄2属的化石仅发现于义县组,而伊克昭龙与戏水龙2属的化石则仅见于九佛堂组。化石证据表明,白垩纪离龙类在辽西范围内的延展分布呈现一个自西向东、由南向北的地理地史演化过程。化石证据也表明辽西的离龙类在较短的时期和较窄的地域范围内经历了一个快速分异演化的过程。长颈潜龙类和短吻满洲鳄类在辽西同时首现于凌源义县组大新房子层,并先后灭绝于义县组的大康堡层和金刚山层。潜龙类最后出现的大康堡层的火山凝灰岩层密集保存了数以千计的潜龙类个体,可能代表该类群于早白垩世发生了与火山喷发活动紧密相关的集群灭绝事件。而后,短吻戏水龙和长吻伊克昭龙同时首现于九佛堂组第2段,并于该组第3段沉积时期内灭绝。整个辽西地域内的离龙类的分布从126~120Ma,在经历了大约6Ma的快速分异演化之后,均于早白垩世阿普第期灭绝。  相似文献   

6.
Two new Early Cretaceous fossil rove beetle species, Paleosiagonium brevelytratum n. gen. n. sp. and Paleosiagonium adaequatum n. gen. n. sp. are described from the Lower Cretaceous Yixian Formation of Liaoning Province, China. They are clearly placed in the extant Piestinae according to the following characters: body elongate and flat; anterior coxae small and globose; abdomen long and parallel-sided, with six visible sterna and one pair of paratergites on segments III–VII. This is the first report on the occurrence of the coleopteran subfamily Piestinae in the fossil record. The new discoveries indicate that Piestinae have originated at least by the Early Cretaceous, at about 125–120 Ma.  相似文献   

7.
The Early Cretaceous Jehol Biota, one of the most important Mesozoic lagerstätten in East Asia, is especially well-known for occurrences of fossil feathered dinosaurs and early angiosperms. However, the terrestrial biodiversity, especially the fossil wood record, is poorly known. In this study, several structurally preserved coniferous wood specimens from the Lower Cretaceous Yixian Formation are investigated, based on collections from the Heichengzi Basin in Beipiao of western Liaoning, Northeast China. Four species referred to four genera of fossil wood are described, including Taxodioxylon heichengziense sp. nov., Thujoxylon beipiaoense sp. nov., Sciadopityoxylon liaoningense Ding and Protocedroxylon shengjinbeigouense sp. nov. These new records enlarge the fossil wood diversity of the Yixian Formation up to 10 species in 9 genera, and provide further insights into the forest vegetation composition of the Early Cretaceous Jehol Biota. Systematic analysis of the floral constitution indicates that the petrified forests of the Yixian Formation are dominated by conifers, represented by Araucariaceae, Podocarpaceae, Sciadopityaceae, Pinaceae and Cupressaceae in the western Liaoning region. Palaeoclimatical analysis of the fossil wood assemblage implies that the western Liaoning region was dominated by a cool temperate, wet and seasonal climate with variable interannual water supply in the western Liaoning region during the Early Cretaceous.  相似文献   

8.
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   

9.
根据发现于辽西朝阳九佛堂组一具有部分头骨的不完整骨架,命名一新的帆翼龙--赵氏龙城翼龙(新属新种).头骨和牙齿形态显示龙城翼龙与宽齿帆翼龙的关系要比与其他翼龙的关系密切,龙城翼龙是目前辽西九佛堂组中发现的唯一的帆翼龙类.帆翼龙科原仅一属种,发现于英国早白垩世地层中,辽西早白垩世新帆翼龙的发现,不但扩大了其地理分布,也证明辽西是晚侏罗世至早白垩世翼龙辐射、分异的重要地区.这对研究翼龙的起源和演化有重要意义.  相似文献   

10.
Three Schizolepis species collected from the Lower Cretaceous layer of the Huolinhe Basin,Inner Mongolia,China are described.These fossils are Schizolepis longipetiolus Xu XH et Sun BN sp.nov.,which is a new species,Schizolepis cf.heilongjiangensis Zheng et Zhang,and Schizolepis neimengensis Deng.The new species is a well-preserved female cone,slender and cylindrical in shape.The seed–scale complexes have long petioles and are arranged on the cone axis loosely and helically.The seed scales are divided into two lobes from the base.Each lobe is semicircular or elongate ligulate in shape,widest at the middle or the lower middle part,with an obtuse or bluntly pointed apex.The inner margin is almost straight and the outer margin is strongly arched.On the surface of the lobe,there are longitudinal and somewhat radial striations from the base to the margin.The seed is borne on the adaxial surface at the base or middle of each lobe.Schizolepis was established in 1847,and,although more than twenty species have been discovered and reported,its phylogenetic position is controversial because of the imperfection of fossils.Most authors have considered there to be a close evolutionary relationship between Schizolepis and extant Pinaceae.Here,we analyze characteristics and compare Schizolepis with Picea crassifolia Kom,which is morphologically most similar to Schizolepis.The results indicate that the genus probably has a distant evolutionary relationship with extant Pinaceae.A detailed statistical analysis of the global paleogeographic distribution of Schizolepis showed that all the fossils of this genus appeared in strata ranging from the Upper Triassic to the Lower Cretaceous in the North Hemisphere,being rare in the Upper Triassic and Lower Jurassic,but being very common from the Middle Jurassic to the Lower Cretaceous,and particularly abundant in the Lower Cretaceous.According to the statistical results,we speculate that the genus originated in Europe in the Late Triassic then spread from Europe to Asia between the Late Triassic and the Late Jurassic.In the Early Cretaceous most species existed in China’s three northeastern Provinces and the Inner Mongolia Autonomous Region and adjacent areas.Combining the paleogeographic distribution of the genus with ancient climatic factors,we deduced that Schizolepis began to decline and became extinct in the Early Cretaceous,and the reason for its extinction is closely related to the icehouse climate during the Early Cretaceous.  相似文献   

11.
A new species of Gobiconodon from the Early Cretaceous in the Lujiatun locality of western Liaoning is erected based on an almost complete skull and lower jaw. It has a flatten skull roof, the lambdoidal crest is strongly curved forward, and the sagittal crest is short and low. There is a protuberance near the anterior base of the zygoma. The preservation of the upper teeth is very rare in all known Gobiconodon, and this provides important information for the study on the formula of Gobiconodon. The new species is the fifth primitive mammal unearthed from the Lujiatun locality, and is of great value for the study of the geological age of the stratigraphy at Lujiatun by primitive mammal material.  相似文献   

12.
Situated at the easternmost area of the Late Mesozoic Jehol Biota, China, abundant fossils, including invertebrates, vertebrates and plants, were collected from the Early Cretaceous Yingzuilazi Formation of the Baishan Basin, southeastern Jilin. The faunal remains from this formation distinctly belong to the Early Cretaceous Lycoptera–Ephemeropsis–Eosestheria assemblage of the Jehol Biota. Based on the gross leaf morphology and epidermal structures, two new species and one indeterminate species of genus Solenites(Czekanowskiales), S. baishanensis sp. nov., S. gracilis sp. nov. and S. sp. are described in this paper. This is the first fossil plant of Czekanowskiales reported from this new fossil locality of the easternmost area of the Late Mesozoic Jehol Biota, China. The new discovery contributes to improve our knowledge for understanding of leaf morphology, epidermal characters and diversity of this genus during the Early Cretaceous time, and extends geologic and geographic distribution of Solenites in northern China and Eurasia. Along with consideration of associated plant and faunal assemblages and sedimentology, we suggest that the regional climate was warm and moderately humid with seasonal temperature and precipitation variations in warm–temperate zone during the Early Cretaceous.  相似文献   

13.
The Staphylinine group of rove beetle subfamilies is a significant animal radiation, and one subordinate monophyletic clade – the ‘Euaesthetine subgroup’ – includes around 3000 species in subfamilies Euaesthetinae and Steninae and has a fossil record dating to the Early Cretaceous. Detailed morphological study of a new well-preserved Cretaceous Burmese amber fossil revealed strong evidence consistent with its taxonomic placement in the euaesthetine genus Octavius. We thus describe Octavius electrospinosus sp. nov., the first Cretaceous record of the genus and of the tribe Euaesthetini. Previously, the oldest records of Octavius and Euaesthetini were from the Eocene (Baltic amber) and discovery of O. electrospinosus sp. nov. therefore nearly doubles the minimum lineage age of Octavius, increasing it by 50 million years. We also briefly review the known Euaesthetine subgroup fossil record and tabulate summary data for all previously described fossils. All are placed in extant genera, and have visible diagnostic generic-level characters including some putative synapomorphies as judged by recent phylogenetic work. Including O. electrospinosus sp. nov., there are now four known Cretaceous species, all of which belong to either Octavius, Nordenskioldia, or Stenus. To explain the long-term morphological stasis in this group of rove beetles, we suggest that the continuous presence of mesic habitats may have buffered these lineages from strong selection for morphological change. Considering the fossils along with phylogenetic hypotheses we suggest the Euaesthetine subgroup originated in the Late Jurassic– Early Cretaceous and the Staphylinine group in the Early Jurassic. We emphasize the derived status of Cretaceous fossils in assessing possible divergence times and the significance of the pre-Cretaceous taphonomic bias for restricting more robust estimates. Further detailed morphological study of available fossils in a phylogenetic framework is badly needed to clarify the phylogenetic positions of these taxa.  相似文献   

14.
Prejanopterus curvirostra, from the Early Cretaceous of La Rioja province, was the first pterosaur genus and species described from Spain. The material comprises disarticulated cranial and postcranial remains from several individuals. The fossil-bearing bed is assigned to the lacustrine Leza Formation (eastern Cameros Basin, NW margin of the Iberian Range). This unit is regarded as either Berriasian-Valanginian or Barremian-Aptian. Prejanopterus curvirostris (specific name emended) was originally diagnosed on the basis of several characters of which the most significant was a lateral curvature of the rostrum. Re-examination of the holotype (rostrum) and paratype (partial rostrum with teeth) indicates that there is no genuine sideways bend of the preserved premaxilla-maxilla segments, but a slight dorsal curvature. Prejanopterus is characterized by a unique combination of characters: an emended diagnosis is provided. In contrast with previous estimates, the wing span of Prejanopterus was probably not much (if ever) in excess of 2 m. A phylogenetic analysis suggests that Prejanopterus is a basal pterodactyloid positioned between Pterodactylus and Cycnorhamphus-Gallodactylus. Prejanopterus represents the first evidence of Pterodactylidae in the Early Cretaceous of the Iberian Peninsula.  相似文献   

15.
<正>The Early Cretaceous Jehol biota of northeastern China contains a diverse group of notostracans, including two genera,Chenops and Jeholops,described here.Chenops is characterized by a combination of an ovate carapace,narrow anal plate,equant distal endites and endopod on the anterior thoracic limbs.In addition to the new species,Chenops yixianensis,the genus also provisionally includes Prolepidurus oblongus Oleynikov, 1968.Jeholops,however,is monotypic,represented by the new species Jeholops hongi.It is characterized by a combination of kazacharthran and notostracan features unique to this taxon.Both new genera are provisionally placed in the taxon Notostraca.More detailed work exploring the morphology of exceptionally-preserved branchiopod crustaceans is needed.The difficulties in placing fossil notostracans into a phylogenetic framework are discussed.  相似文献   

16.
Prophaenognatha robusta gen. et sp. nov. (Scarabaeoidea: Scarabaeidae: Aclopinae), the best-preserved aclopine fossil so far, is described and illustrated from the Upper Jurassic–Lower Cretaceous Yixian Formation of the Jehol Biota, western Liaoning Province, NE China. The key to extinct and extant genera of Aclopinae is given and the monophyly of extant and fossil Aclopinae lineages is supported by five character states. The new taxon provides evidence about the evolution of Scarabaeoidea with its phylogenetic position inferred based on 68 morphological characters.  相似文献   

17.
A new somphospondylan sauropod (Dinosauria, Titanosauriformes): Gannansaurus sinensis gen. et sp. nov. from the Late Cretaceous Nanxiong Formation of Ganzhou Basin, Jiangxi Province of southern China is erected based on one nearly complete dorsal vertebra and a mid-caudal vertebra. It is characterized by two centroprezygapophyseal lamina fossae; large, square-shaped concavity formed by centroprezygapophyseal lamina and dorsal margin of the centrum; large infraparapophyseal fossa; three openings present within the large lateral concavity, which occupy 65% length of the centrum; the posterior centroparapophyseal lamina (PCPL) and the anterior centroparapophyseal lamina (ACPL) weakly developed; the posterior centrodiapophyseal lamina (PCDL) separated by an infradiapophyseal fossa into two branches dorsally; parapophyseal and diapophyseal laminae cross to form "K" configuration. It shares some characters with the Early Cretaceous form-Euhelopus, indicating that it is more closely related to Euhelopus rather than to other titanosauriform sauropods. This means Gannansaurus may have a close phylogenetic relationship with Euhelopus.  相似文献   

18.
A new species, Procretevania mitis sp. nov., is described from the Early Cretaceous of Yixian Formation at the Huangbanjigou, Beipiao City, western Liaoning, China. Based on new morphological data, a key of Procretevania Zhang and Zhang, 2000 is provided. Forewing venations, body and forewing lengths, localities and horizons of various genera of Evaniidae in amber and compression fossils are summarized for comparison. Evaniidae have a high degree of venational diversity, while more complex forewing venations for Lebanevania and Mesevania suggest that they may represent the stem group of the Evaniidae. High diversity of Evaniidae in the Early Cretaceous implies that Evaniidae might have radiated before the Early Cretaceous. Furthermore, comparison of body and forewing lengths of amber and fossil genera indicate that the amber specimens have relatively smaller size.  相似文献   

19.
始祖鸟的发现被认为是19世纪最重要的科学发现之一,迄今为止共发现了7枚保存骨骼、羽毛印痕的化石标本和1枚单根羽毛化石标本。由于始祖鸟既显示了明显的爬行动物的特征又保存了精美的羽毛,140多年来人们一直将其作为介于恐龙与鸟类之间的“中间环节”(“missing link”),但更倾向认为它是世界上最古老的鸟,或鸟类的始祖。由于始祖鸟化石稀少,加之地理分布十分局限,长期以来国际上一直围绕鸟类起源问题展开了激烈的争论,提出了各种各样的假说。直到20世纪90年代,在中国辽西晚中生代地层中发现了大量长羽毛的恐龙和原始鸟类化石,有力地支持了鸟类起源于小型兽脚类恐龙的学术观点,使赫 140多年前提出的“假说”成为当今国际科学界占主流地位的学说和理论,基本解决了长期困扰国际科学界的鸟类起源问题,遗憾的是,在过去的几年中,中国一直没有发现与德国始祖鸟十分接近或与德国始祖鸟处于同样进化水平的原始鸟类化石,这种缺憾使我们难以对鸟类定义问题进行深入的研究和探讨,2002年,笔者等在中国辽西早白垩世断层中发现了2种初鸟类化石,即中华神州鸟和东方吉祥鸟。通过比较解剖学研究和支序分析,这2种初鸟类要比始祖鸟略微进步一些,在研究鸟类的早期演化方面具有重要意义;但仍然难以对鸟类定义问题作进一步研究。本文首次报道了一件采自中国河北省丰宁县龙凤山桥头组的初鸟类化石——华美金凤鸟(新属、新种)(Jinfengopteryx elegans gen.et sp.nov),与其共生的化石有Lycoptera davidi,Peipiaosteus pani,yanosteus longidorsalis(鱼类);Jibeinia luanhera,Protopteryx fengningensis(鸟类);Ephemeropsis trisetalis(昆虫)及少量植物。支序分析表明,华美金凤鸟处于初鸟类谱系树的基部,比始祖鸟略微原始,与后者为姊妹群关系。奔龙等兽脚类恐龙是它们的外类群。金凤鸟、始祖鸟是中华神州鸟等原始鸟类的外类群。这说明华美金凤鸟处在恐龙向鸟类演化过程中一个非常关键的位置,是世界上迄今所发现的最原始的初鸟类。华美金凤鸟的发现在研究鸟类起源、恐龙-鸟类的系统关系等方面具有重要的科学意义。  相似文献   

20.
A new species,Ginkgo huolinhensis sp.nov.,with well-preserved cuticle from the Lower Cretaceous,Huolinhe Formation of Huolinhe Coal Field in Inner Mongolia,China,was studied morphologically and anatomi...  相似文献   

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