共查询到18条相似文献，搜索用时 140 毫秒
1.
2.
本文总结了古神翼龙类的特征,尤其是对中国发现的没有牙齿的翼龙类(包括古神翼龙类、朝阳翼龙类及神龙翼龙类)进行系统总结。通过对比,把中国的古神翼龙类建立两个新的亚科:中国翼龙亚科及华夏翼龙亚科。从古神翼龙类头骨形态变化来看,其演化趋势是头骨由低长向短高变化,这一变化的原因可能与其食性变化有关。根据在辽西凌源四合当九佛堂组发现的一几乎完整的化石骨架建立了中国翼龙新种:凌源中国翼龙(新种),它具有以下特征:鼻眶前孔的长度与高度之比率为3.20;吻部指数为3.03;股骨与胫骨长度之比率约为0.66以及第2翼指骨与第1翼指骨长度之比率为0.85。根据发现于辽西朝阳九佛堂组的另一个体较小的古神翼龙类化石骨架,建立华夏翼龙属一新种:返祖华夏翼龙(新种)。虽然它个体较小,但是它具有华夏翼龙类似的头骨脊,然而它的第2和第3翼指骨的后面具有原始喙嘴龙类翼龙的沟状结构,以区别于其它的华夏翼龙类。返祖华夏翼龙的翼指骨后部沟状结构的出现,应为返祖现象的体现。而这一现象,在翼手龙类中为首次报道。 相似文献
3.
根据发现于辽宁省西部下白垩统九佛堂组的一近乎完整的梳齿颌翼龙类下颌，确立了一新属新种：短颌辽西翼龙Liaoxipterus brachyognathus gen.et sp.nov．短颌辽西翼龙以它前部扩张的下颌缝合部，左右第四齿槽间的距离最宽等特征不同于发现于辽西及其周边地区任何具有头骨保存的翼龙类，基于其扁宽的下颌吻端，牙齿大小分异小及短的下颌缝合部，把它归入梳齿翼龙类，短颌辽西翼龙以其较少的牙齿数目区别于其他梳齿颌翼龙， 相似文献
4.
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
5.
6.
达尔文翼龙的发现及其意义 总被引：1，自引：0，他引：1
达尔文翼龙为中等大小的翼龙类, 发现于辽西辽宁省建昌县玲珑塔中侏罗世髫髻山组, 是目前已知唯一由原始类群(非翼手龙类)向进步类群(翼手龙类)演化的过渡类型。它既具有原始类群的特征: 比如尾长, 多于20节尾椎椎体, 且尾椎椎体由极度加长的、纤细的前后关节突及脉弧所包裹, 构成一僵硬的尾部, 第五脚趾具有两个长的趾节; 又具有进步类群的特征: 比如头骨加长, 鼻孔和眶前孔愈合为一大的鼻眶前孔, 颈椎椎体长, 没有或者颈肋退化; 翼掌骨与肱骨的比率介于原始类群和进步类群之间。达尔文翼龙的发现具有重要意义, 它填补了由原始翼龙类向进步翼龙类演化的空白, 为生物宏观演化(模块演化)机制-即组成生物体的模块在短时间内共同演化提供例证。从达尔文翼龙的骨骼结构变化上看, 空中丰富的食物来源(比如飞行能力差的、带羽毛的恐龙、滑翔的哺乳动物、小的翼龙及昆虫等), 可能为导致翼龙头骨和颈部首先演化的原因之一。达尔文翼龙的发现, 有可能打破对翼龙类传统分为两大类的方法。 相似文献
7.
8.
目前中国已经有8个省及自治区发现翼龙化石,时代分布从中侏罗世一直延续到晚白垩世。对近年来大量发现翼龙化石的辽宁玲珑塔和产出浙江翼龙的塘上组两个有争议的化石层位进行了U-Pb同位素测年,得到了最新的年龄数据。在玲珑塔地区含化石沉积地层的碎屑锆石获得了最小150 Ma的同位素年龄,可能代表了化石层位的时代下限,表明含化石层的时代为晚侏罗世。同时,也获得了浙江天台盆地富含恐龙蛋化石层下伏的塘上组和临海上盘浙江翼龙化石地点的塘上组(小雄组)凝灰岩的年龄,分别为113 Ma和90Ma,证实了浙江翼龙产于晚白垩世,而浙江地区不同盆地的塘上组应属于不同时期的沉积。在辽西和浙江这两个重要的有争议的翼龙化石地点的同位素最新年龄数据的基础上,对中国发现的翼龙化石的地层序列和时代框架进行了初步的总结,表明早白垩世翼龙占优势地位。 相似文献
9.
中国西北和东北地区发育中生代河湖相沉积的陆相盆地,其中赋存丰富的脊椎动物化石群,包括天山北部准噶尔盆地的乌尔禾翼龙动物群、天山南部吐哈盆地的哈密翼龙动物群和辽西热河生物群富含翼龙化石。乌尔禾和哈密翼龙动物群都发现于下白垩统吐谷鲁群中,两者的繁盛时间大致相当,这两个动物群的翼龙个体数量巨大,但是物种多样性很低。乌尔禾翼龙动物群的化石多保存在半深湖环境沉积的细砂岩和粉砂岩中,化石保存较为完整,主要为正常死亡;哈密翼龙动物群的化石富集保存在滨浅湖环境事件沉积的风暴岩中,大都经过了大型风暴的短距离搬运和快速埋藏,骨架分散,但几乎所有单个骨骼完整。东北地区的热河生物群翼龙种类众多,共生包括鱼类、两栖类、恐龙等其他爬行类、鸟类和哺乳类等脊椎动物,生物多样性极为丰富,大多保存在半深湖-深湖环境形成的页岩中,骨架多为完整保存,是火山爆发事件导致其集群死亡,并被火山灰快速埋藏,与新疆的动物群面貌明显不同。根据天山南北的翼龙动物群初步对比,乌尔禾翼龙动物群的主要优势类群准噶尔翼龙类,在天山北部的准噶尔盆地及相邻的蒙古西部地区都有分布,与天山南部的哈密翼龙动物群中已知唯一翼龙类群哈密翼龙完全不同,两者亲缘关系很远。因此认为在中生代,天山的隆升就已经达到了一定的高度,并对翼龙的南北迁徙交流形成了有效的地理阻隔。依据中国东北和西北地区早白垩世翼龙动物群对比,认为辽西及相邻周边地区由于华北克拉通破坏,导致大量火山活动,造成了生态环境的多样性和生物种类的快速更替,从而形成了热河生物群独有的极高的生物多样性,而缺少火山活动、环境相对单一的西北陆相盆地,虽然翼龙类具有数以千万计的庞大居群,但是物种多样性很低。华北克拉通破坏导致的辽西地区频繁而强烈的火山活动,是形成中国西北和东北早白垩世生物多样性差异的重要原因。 相似文献
10.
中国辽宁西部早白垩世翼龙类化石非常丰富,其上部的九佛堂组翼龙类组合以含有丰富的无齿的古神翼龙科、朝阳翼龙科等进步类型而与下部的义县组翼龙类组合相区别。本文描述了辽宁西部建昌盆地九佛堂组一新的大型翼龙类化石,其以上下颌无齿、吻端指数为3.7、前颌骨背支细长且封闭鼻眶前孔背缘、很大的鼻眶前孔后端超过上下颌关节位置、轭骨的上颌骨突基部宽大而应被归入朝阳翼龙科(Chaoyangopteridae)神州翼龙属(Shenzhoupterus)。其以较大的体形(翼展2.05 m)、平直的上下颌咬合面、轭骨的眶后骨突较泪骨突长且基部略宽、第4～7颈椎长度依次减小等特征,区别于朝阳神州翼龙(Shenzhoupterus chaoyangensis),而被命名为三亚神州翼龙(新种)(Shenzhoupterus sanyainus sp. nov.)。这是辽宁西部早白垩世翼展最大且不具牙齿的翼龙类属种,它的发现丰富了九佛堂组翼龙类组合内容,对认识朝阳翼龙科的骨骼形态与生态习性亦具有积极意义。 相似文献
11.
DONG Zhiming lv Junchang Research Center of Paleontology Stratigraphy Jijin University Changchun Institute of Paleontology Paleoanthropology Chinese Academy Sciences Beijing Institute of Geology Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》2005,79(2):164-167
Based on a nearly complete lower jaw from the Early Cretaceous of Liaoning Province, a new ctenochasmatid pterosaur: Liaoxipterus brachyognathus gen, et sp. nov. is erected. Liaoxipterus brachyognathus is different from any known pterosaurs with skulls preserved from western Liaoning Province and its peripheral areas in that the anterior part of the mandibular symphysis is expanded, being widest between the fourth alveolus of each side. Liaoxipterus brachyognathus is assigned to Ctenochasmatidae based on the following characters: the rounded anterior end of the lower jaw is spatulated and dorsoventrally flattened and marked heterodonty in the dentition is absent. It differs from other ctenochasmatid pterosaurs in having relatively small number of teeth. Liaoxipterus is distinguished from some ornithocheirids, which have expanded anterior parts of the mandibular symphyses, such as Anhanguera piscator,Coloborhynchus robustus in which the teeth of the new pterosaur are not as variable. 相似文献
12.
KOBAYASHI Yoshitsugu 《《地质学报》英文版》2005,79(6):766-769
The cross-section and surface structures of wing membranes from the ctenochasmatid pterosaur Beipiaopterus chenianus were observed through a scanning electron microscope （SEM）. The results show that the wing membrane contains a high density of blood vessels, implying strong thermoregulatory function, similar to that of a bat wing membrane. This is the first comparison of the microstmctures of pterosaur wing membranes with those of the modem bat. It is inferred that a bat-like physiology exists, at least in relatively small pterosaurs suggesting that these pterosaurs were warm-blooded, active fliers. 相似文献
13.
In recent years the Late Cretaceous (Santonian) terrestrial vertebrate locality at Iharkút (western Hungary) has yielded well-preserved remains of lizard taxa besides the remains of fishes, amphibians, turtles, crocodiles, pterosaurs and dinosaurs. Previously the polyglyphanodontine lizard Bicuspidon aff. hatzegiensis has been reported from Iharkút. However, recent excavations at this site produced more lacertilian remains including new polyglyphanodontine material, namely a maxilla and two dentaries which suggest the presence of a new genus in the Iharkút fauna. This previously unknown lizard (described here as Distortodon rhomboideus n. g. n. sp.) is distinct from other polyglyphanodontines such as Bicuspidon, Paraglyphanodon, Polyglyphanodon, Dicothodon and Peneteius. It differs from these genera mainly in having the lingual cusp situated more distally compared to the labial one on its bicuspid teeth located in the distal part of the tooth row, thus the crowns having a unique rhomboidal shape in occlusal view. Distortodon rhomboideus further strengthens the dominance of borioteiioid lizards in the Iharkút fauna. The growing presence of borioteiioids in European localities supports previous theories which suggest some paleobiogeographic connections between the western Tethyan archipelago and North America in the Late Cretaceous. 相似文献
14.
近年来,在中国辽宁西部、内蒙古东南部、河北北部中侏罗世髫髻山组和九龙山组中发现了丰富的脊椎动物、无脊椎动物和植物化石,这一化石群被称为燕辽生物群。燕辽生物群已正式命名的脊椎动物26属28种,包括鱼类1属1种、两栖类4属4种、有鳞类1属1种、翼龙类10属12种、兽脚类恐龙5属5种、哺乳类5属5种。燕辽生物群的脊椎动物化石对研究长羽毛兽脚类恐龙的演化、翼龙类的分类演化、滑体两栖类的分异等具有重要意义。虽然辽宁西部及邻区燕辽生物群脊椎动物的多样性不及同一地区早白垩世的热河生物群,但它为认识这一地区晚中生代生物群的演替提供了极为重要的依据。 相似文献
15.
Pangupterus liui gen. et sp. nov. from the Jiufotang Formation of Sihedang, Lingyuan City, Liaoning Province is erected based on a nearly complete lower jaw. It is characterized by having a total of 36 slender curved teeth with sharp tips, forming a distinct fish-grabbing mechanism; the teeth are well-spaced and are circular in section; the length ratio of the mandibular symphysis to the whole jaw is 20%; and the ratio of the tooth root width to tooth length is 12%. Toothed pterosaurs make up about 56.3% of the pterosaur assemblage from the Jiufotang Formation, which indicates that toothed forms played a key role in the ecosystem. 相似文献
16.
Brian ANDRES 《《地质学报》英文版》2012,86(6):1356-1365
Phylogenetic analyses of early pterosaur species are relatively new and contradictory. However, they imply a similar evolutionary history for early pterosaurs: a large divergence of all major early groups of pterosaurs before the first named pterosaur species appeared in the fossil record. This large, unsampled divergence may be a record of the initial adaptive radiation of the pterosaurs, but a recent comprehensive phylogenetic analysis reconstructs named Triassic pterosaur species grouped together in a monophyletic clade with all other major groups diverging later. Ten patterns that characterize adaptive radiations put forward by Gavrilets and Losos (2009) are assessed for congruence with the comprehensive phylogeny and two previous phylogenies to determine which are consistent with our notions of an adaptive radiation. Of the eight patterns that can be applied to pterosaurs, only six vary between pterosaur phylogenies. Of these six patterns, all apply to the three phylogenies with varying amounts of support. For many patterns, however, the comprehensive phylogeny has a greater magnitude, shorter time span, or is the only topology within which they can be assessed. Pterosaurs are characterized by an adaptive radiation no matter which phylogeny is considered, but congruence with the fossil record increases the support and information content of a phylogeny by reducing the time and area within which to reconstruct evolutionary history. 相似文献
17.
Since their discovery, pterosaurs have prompted much discussion about their ecology and feeding habits. Most pterosaur specimens are known from marine deposits (Kellner, 2003), though this may represent a bias towards preservation rather than necessarily a habitat choice. Recent discoveries of terrestrial deposits (e.g. the Yixian Formation) have also yielded numerous pterosaurs and our knowledge of their diversity has increased dramatically in recent years. 相似文献