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1.
Abstract:  The lectotype of the Middle Jurassic theropod dinosaur Megalosaurus bucklandii , a right dentary, can be diagnosed on the basis of two unique characters: a longitudinal groove on the ventral part of the lateral surface of the dentary and a slit-like anterior Meckelian foramen. This taxon, the first dinosaur to be scientifically described, is therefore valid. Currently, however, no further material can be referred to this species with any certainty. Megalosaurus bucklandii occupies an uncertain systematic position but is not an abelisaurid or coelophysoid. Additionally, it does not possess the diagnostic dentary characters that are present in all known spinosauroids. Owing to this uncertainty, use of the family Megalosauridae should be discontinued until such time as its systematic position becomes clearer.  相似文献   

2.
Abstract:  Only two ornithomimid genera, Ornithomimus and Struthiomimus , are currently known from the Upper Cretaceous of North America. However, a number of ornithomimid elements from Alberta's Dinosaur Park Formation (Upper Campanian), cannot be assigned to either Ornithomimus or Struthiomimus . These bones, including a frontal, caudal vertebrae, and unguals of the manus and the pes, come from animals significantly larger than any previously known Judithian ornithomimid. The frontal exhibits several unusual features, including transverse expansion over the prefrontals, and extreme reduction of the supratemporal fossae. Caudal vertebrae are characterized by neural arches that are posteriorly shifted and transversely expanded. Manual unguals possess a highly concave articular surface, a flexor tubercle divided by a sulcus, and a broad claw. Pedal unguals display highly concave articular surfaces, and a ridge-like flexor tubercle dividing a deep ventral fossa. Although it is difficult to know whether these elements represent a single taxon, this is currently the most parsimonious hypothesis. This study demonstrates how isolated dinosaur bones can extend our knowledge of dinosaur faunas.  相似文献   

3.
HYBODONT SHARKS OF THE ENGLISH BATHONIAN AND CALLOVIAN (MIDDLE JURASSIC)   总被引:1,自引:0,他引:1  
Abstract:  Recent bulk sampling and study of museum collections has revealed a high diversity of hybodont sharks from the English Bathonian, with 15 species being recognised. In addition, study of dental and skeletal material from the English Callovian has allowed the diagnosis of a new genus and species, Planohybodus peterboroughensis gen. et sp. nov., allowing the Bathonian species Hybodus grossiconus Agassiz to be referred to Planohybodus . Two additional new genera, Secarodus and Frangerodus , are erected for the Bathonian taxa Hybodus polyprion Agassiz and Strophodus lingualis Woodward, respectively. Egertonodus duffini sp. nov. is described and the diagnosis of Egertonodus based on dental material is discussed. The previously unrecorded Hybodus sp., Parvodus sp., and Lonchidion sp. are recognised but left in open nomenclature. Asteracanthus medius (Owen) is recorded in the British Bathonian for the first time, and the status of Bathonian nominal species of Asteracanthus are assessed. Bathonian hybodonts showed great diversity in trophic ecology and many of the species are specific to particular palaeoenvironments.  相似文献   

4.
记河北省后城组新发现之小型兽脚类足迹(英文)   总被引:2,自引:0,他引:2  
几十年前人们就已经开始研究中国东北侏罗纪—白垩纪界线附近地层中的小型兽脚类恐龙足迹,虽然这些遗迹化石比辽宁省义县组带羽毛的恐龙及其他实体化石逊色了许多。本文记述了河北省承德南双庙后城组(土城子组)最下部河流相沉积中发现的一组兽脚类恐龙足迹。南双庙足迹具有三趾,趾粗大,其形态与美国下侏罗统经典的"brontozoid"足迹(Gral- lator,Anchisauripus和Eubrontes)相符。虽然许多产自辽宁土城子组中基本同时的brontozoid足迹被鉴定为小型的跷脚龙足迹属(Grallator),但南双庙足迹更大一些(全长可达28.8 cm),可能应该归入安琪龙足迹属(Anchisauripus)。南双庙足迹很可能是一群小型兽脚类行走而产生。在辽宁义县组的兽脚类恐龙中,最可能留下这类足迹的是小型的窃蛋龙类——尾羽龙(Caudipteryx)。不过这个解释还很勉强,因为这些足迹缺乏鉴定性特征,而且河北的后城组与辽宁的义县组之间还有一定的时间及地理间隔。  相似文献   

5.
一小的甲龙,作为甲龙科(Ankylosauridae)中一新属新种,明星天池龙(Tianchisaurus nedegoapeferima gen. et sp. nov.)被记述。化石是1974年,新疆大学地质地理系的师生在新疆阜康县三工河地区作野外实习时采得,其产地的地层层位经新疆石油管理局东疆石油指挥部彭希龄核对为中侏罗世头顿河组。化石包括破的头骨碎片,五个颈椎,六个背椎,一个完整荐部(由七个椎体组成),三个尾椎,和许多膜质的甲胄,甲板,以及一些四肢骨。标本编号:V.10614,新属新种的特征是:一个小的,原始的,体长约三米的甲龙;头骨较高,有小的膜质的甲片复盖;下颚高,外侧无甲片复盖,有纵的饰纹,环椎与枢椎不愈合;颈椎椎体短,双凹型;背椎椎体较长,双平型,横突与背肋不愈合;荐部由七个愈合脊椎组成:前两个是背椎,形成一个荐前棒(presacral rod),最后的一个是尾椎,四个荐椎的椎体是整个椎柱中最大的,荐椎的神经棘愈合,形成一个纵的板状脊,远端的尾椎愈合形成小的,扁的尾锤。股骨直,骨干上有饰纹,第四转子呈嵴状。蹠骨和趾骨为甲龙型,与晚期甲龙的蹠骨和趾骨比较显得瘦小。在肩部有一个由四对大的膜质的甲板愈合形成肩甲带,甲板厚有发育的中嵴。在身体覆盖着许多大小不同,形状各异的甲片。Tianchisaurus nedegoapeferima的种名是应著名科幻电影导演Steven Splelberg之约请赠送给大型科幻电影片-侏罗纪公园之明星们:Sam Naill, Laura Dern, Jeff Goldblum, Richard Attenborough, Bob Peck和Martin Ferrsro.我们称之明星天池龙(Tianchisaurus nedegoapeferima gen. et sp. nov.)。Tianchisaurus nedegoapeferima是目前甲龙亚目在亚洲的最早纪录。它的发现将甲龙的化石记录推到中侏罗世。  相似文献   

6.
新疆塔里木盆地侏罗系分布广泛,在库车凹陷和塔西南区发育最好。目前对库车凹陷的三叠纪和侏罗纪孢粉植物群研究较为深入,而对塔西南区侏罗纪孢粉化石专题研究不多,尚未建立孢粉组合。作者基于塔西南区乌恰中侏罗统塔尔尕组发现的孢子花粉33属48种的研究,建立了塔尔尕组孢粉组合。该组合以掌鳞杉科花粉Classopollis的优势和真蕨目桫椤科孢子Cyathidites的繁盛为特征,并含有丰富多样且颇具侏罗纪色彩的孢子花粉化石类型。该组合与西欧和俄罗斯巴柔期至巴通期孢粉组合以及北美和澳大利亚巴柔期至卡洛夫期孢粉组合可以进行对比;与我国新疆库车恰克马克组、陕西延安直罗组和湖北兴山沙溪庙组等孢粉组合也可对比。根据孢粉学证据,塔尔尕组的时代应属于中侏罗世晚期(巴通期至卡洛夫期)。当前孢粉植物群支持我国侏罗纪南北植物地理区系之西端分界之划分方案,即塔西南乌恰处于界线以南,而库车处于分界以北。  相似文献   

7.
中国内蒙古中侏罗世脉翅目昆虫化石—新科(英文)   总被引:1,自引:0,他引:1  
建立脉翅目昆虫化石新科———Grammolingiidaefamnov .,并描述该科化石 3新属 6新种 :Grammolingiaboigen .nov .ofsp .nov .,Litholingiarhoragen .nov .ofsp .nov .,Litholingiaeumorphagen .nov .ofsp .nov .,Litholing iapolychotomagen .nov .ofsp .nov .,Leptolingiajurassicagen .nov .ofsp .nov .,Leptolingiatianyiensisgen .nov .etsp .nov ..给出了新科的属级检索表 ,描述的所有模式标本均采自于内蒙古自治区宁城县中侏罗世九龙山组地层中。标本分别保存在义县博物馆和首都师范大学生物系。本次发现再次表明目前关于脉翅目昆虫的认识仍然十分贫乏。  相似文献   

8.
Abstract  A new family, Grammolingiidae of fossil lacewings is erected, of which 3 new genera and 6 new species are described and illustrated: Grammolingia boi . gen. nov. et sp. nov., Lithlingia rhra gen. nov. et sp. nov., Litholingia eumopha gen. nov. et sp. nov. and Litholingiu polychotom gen. nov. et sp. nov., Leptolingia jurassica gen. nov. et sp. nov. and Leptolingia tianyiensis gen. noc. et sp. nov. A key to genera within this new family is provided. All specimens described were collected from the Middle Jurassic Jiulongshan Formation of Eastern Inner Mongolia, China. The present discovery demonstrates that present knowledge of the Jurassic Neuropetra fauna remains very poor. The fossil specimens are deposited in Yizhou Fossil Museum and Department of Biology, Capital Normal University, respectively.  相似文献   

9.
垣曲盆地新发现的始爪兽类化石   总被引:3,自引:1,他引:2  
记述了在垣曲盆地始新世地层两个层位中发现的始爪兽科化石 3个种 ,其中包括 1个新种———周氏路南兽 (Lunaniazhouisp .nov .)。新种与属型种杨氏路南兽不同在于个体小、齿冠低、下前尖和下前脊及下斜脊更退化。  相似文献   

10.
山东莱阳晚白垩世恐龙蛋化石一新类型   总被引:4,自引:0,他引:4  
山东莱阳是中国最早发现的含有丰富的晚白垩世恐龙及恐龙蛋化石产地。上个世纪50~60年代,周明镇(1951,1954)及杨钟健(1954,1959,1965)对莱阳首次发现的恐龙蛋化石进行了研究。1974年,赵资奎、蒋元凯在前人工作基础上,采用显微镜技术方法重新研究了莱阳恐龙蛋壳的显微结构,结果发现它们的显微结构有很大差异。根据赵资奎(1975)提出的恐龙蛋分类方法(Parataxonomy),将莱阳地区已发现的恐龙蛋分别归入圆形蛋科(spheroolithidae)、椭圆形蛋科(Ovaloolithidae)和长形蛋科(Elongatoolithidae)等3个科,共5个属12个种(赵资奎,1979,1993)。最近,大连自然博物馆在整理馆存的化石标本时,发现有4枚形状为扁圆形的恐龙蛋化石是1973年10月从山东莱阳将军顶采集到的。根据目前有关莱阳地区晚中生代地层划分修订的标准(胡承志等,2001),这些标本的出土层位应为上白垩统王氏群将军顶组。我们的初步观察表明,蛋化石的形状、大小及其蛋壳显微结构特征与上述已报道的莱阳恐龙蛋3个类群的明显不同,在此简单记述,以期对莱阳地区晚白垩世恐龙蛋群的综合研究提供些许资料。  相似文献   

11.
Abstract:  Vertebrae of Suuwassea demonstrate an interesting combination of plesiomorphies and autapomorphies among known members of the Flagellicaudata. The cranial cervical vertebrae have proportions close to Diplodocus but resemble those of Apatosaurus except by having greatly reduced cranial and caudal spinozygapophyseal laminae. As a result, they have craniocaudally compressed, caudally positioned spinous processes excavated on all sides by fossae. The cranial thoracic vertebrae are again similarly proportioned as those of Diplodocus but are morphologically similar to those of Apatosaurus . The most distinguishing feature of Suuwassea caudal vertebrae are the short, amphiplatyan, distalmost 'whiplash' caudal vertebrae. These may be either a retention of or a reversal to the plesiomorphic sauropod condition because classic flagellicaudatan, biconvex distalmost caudals occur in the Middle Jurassic of England.  相似文献   

12.
首次利用扫描电子显微镜观察川东新田沟组介形类化石的保存情况,并利用X射线能谱分析部分化石的元素含量及分布。研究发现新田沟组介形类壳体绝大部分方解石化,不同层位介形类壳质方解石化有所不同,且方解石化特点显示其可能与有机质作用有关。通过与前人研究结果对比发现,新田沟组壳体保存处在介形虫壳体埋藏作用的第二阶段和第三阶段。  相似文献   

13.
Abstract:  A single specimen of a new species of oribatid mite belonging to the genus Jureremus Krivolutsky, in Krivolutsky and Krassilov 1977 , previously described from the Upper Jurassic of the Russian Far East, is described as J. phippsi sp. nov. The mite is preserved by iron pyrite replacement, and was recovered by sieving from the Oxford Clay Formation (Jurassic: Upper Callovian) of South Cave, Yorkshire. It is the first record of a pre-Pleistocene mite, and the second species record of the family Cymbaeremaeidae, from the British Isles; also, it is only the third record of Acari from the Jurassic Period. The presence of a terrestrial mite in a sedimentary sequence of open marine origin is noteworthy, and suggestions for its mode of transport to the site of deposition are discussed.  相似文献   

14.
记中国南方广东省南雄盆地晚白垩世一新的窃蛋龙类化石   总被引:1,自引:0,他引:1  
文中记述的窃蛋龙类一新属新种:遗忘始兴龙Shixinggia oblita gen.et sp.nov.是由北京自然博物馆于1995年采自中国广东省南雄盆地的始兴县。它具有以下特征:相对短的肠骨前突,肠骨高度与长度之比率大,并且肠骨的前突及后突的腹边缘均高于髋臼的背边缘。遗忘始兴龙还显示另一特征为股骨近端转子嵴内表面具有一大的气孔,胫骨近端也有类似的相对小的孔,而这些孔在其他已知的窃蛋龙类中均没有报道。这是继2003年报道的黄氏河源龙之后,中国南方第二个新的窃蛋龙类化石。  相似文献   

15.
浙江天台盆地晚白垩世恐龙蛋新类型(英文)   总被引:1,自引:0,他引:1  
浙江天台盆地上白垩统赖家组和赤城山组是我国最重要的恐龙蛋化石产出地层之一。近年来,我们对天台盆地陆相红层中的恐龙蛋化石层位进行了详细厘定,对恐龙蛋类型进行了系统描述,并对前人报道的一些属种进行了分类订正。研究显示,天台恐龙蛋化石群基本上可分为7蛋科、12蛋属和15蛋种,代表了我国晚白垩世早期的恐龙蛋化石组合。本文简要报道了主要产自天台盆地赤城山组的双塘似蜂窝蛋(新蛋属、新修订种)、木鱼山半蜂窝蛋(新蛋属、新蛋种)、国清寺副蜂窝蛋(新修订种)、天台棱柱形蛋(新修订种)和张头槽马赛克蛋(新蛋属、新修订种)等3新蛋属、5新蛋种和修订种的主要鉴定特征,并建立一新蛋科——似蜂窝蛋科。  相似文献   

16.
北票尖山沟义县组下部两种膜翅目昆虫化石   总被引:3,自引:0,他引:3  
描述了产自辽这西部北票上园地区尖山沟上侏罗统义县组上部膜翅目昆虫化石1新属2新种。新属新种Procretuania Pristina gen.et sp.nov.归人白垩旗腹姬蜂科(Cretevaniidae),新种Gurvanotrupes liaoningensis sp.nov。归入细蜂科(Serphidae).这是Cretevaniidae科和Gurvanotrupes属在我国的首次发现  相似文献   

17.
Abstract:  On the basis of six articulated individuals from the middle to late Albian lithographic limestone at Tlayúa near Tepexi de Rodríguez (Puebla, Mexico), a new species of ophiuroid, Ophiactis applegatei , is described. The material adds to the rather poor record of Early Cretaceous brittlestars and represents the oldest known member of the family Ophiactidae, being based on well-preserved and articulated specimens and thus reasonably well defined morphologically. The rarity of ophiuroids, their complete preservation as well as the unnatural contortions of their arms suggest these specimens to be allochthonous, having been transported into a hostile environment where burial was rapid.  相似文献   

18.
陕西中三叠世中蝎蛉科两新属和新种(昆虫纲,长翅目)   总被引:2,自引:2,他引:0  
记述中蝎蛉科Mesopanorpodidae 2新属、新种:Triassochoristites jinsuoguanensis gen.et sp.nov.,Forcinerva tongchuanensis gen.et sp.nov.化石标本采自陕西铜川中三叠世铜川组下段上部的灰绿色泥岩和页岩。这些新属、种系陕西昆虫群(陕西生物群的一个类别)铜川昆虫组合的新成员。铜川组的时代相当于欧洲拉丁尼期(Ladinian Stagc)。  相似文献   

19.
于2006-2011期间的4次野外发掘中,在泥河湾盆地的山神庙咀遗址发现了大量犬科化石,材料包括残破颅骨、前颌骨、上颌骨、若干下颌骨及头后骨骼的主要部件,其中的头后骨骼是迄今在中国发现的早期犬属化石中最为完整的.依据有关形态特征和测量数据,将其归入直隶狼(Canis chihliensis).具体特征如下:体形较大,I3强大,P4窄长,原尖发育,M1前后向变扁并具宽阔的齿带状次尖,m1具下后尖和下内尖,相对其M1大小而言,上、下第二臼齿较大,m2下跟座宽阔等.其头部骨骼及牙齿测量数据与现代灰狼的较为接近,但头后骨骼数据较后者明显为小.该种的最大特征是其下臼齿舌侧齿尖的退化和P4窄长及M1前后方向变扁.但山神庙咀犬属材料的ml舌侧齿尖的发育程度变异较大,因此,仅仅依据ml的特征不足以区分直隶狼和拟豺(Xenocyon dubius (=Cuon dubius)),尽管后者的鉴定与分类问题尚存争议,但直隶狼与被归入拟豺的材料有更多相似之处,它们与非洲野犬(Lycaon pictus)差异很大.山神庙咀遗址化石层与邻近的小长梁遗址文化层时代相当或稍晚,大约为1.3 Ma.  相似文献   

20.
Abstract: Larval and metamorphosed Ferganobatrachus riabinini (Temnospondyli, Brachyopoidea), metamorphosed Kokartus honorarius (Caudata, Karauridae), an indeterminated karaurid (Karauridae indet.) and, presumably, anurans (?Anura indet.) are represented by isolated cranial and postcranial skeletal elements in the Middle Jurassic (Bathonian–Callovian) Balabansai Svita of the Fergana Depression, Kyrgyzstan. The Balabansai vertebrate assemblage is one of the few faunas in which non‐lissamphibian temnospondyls, stem caudates and anurans occur together. The presence of a supraglenoid foramen and a complex strap‐like glenoid on the scapulocoracoid in Kokartus supports its basal phylogenetic position within the Caudata.  相似文献   

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