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1.
道虎沟化石层分布于内蒙古宁城县道虎沟以及毗邻的河北北部和辽宁西部等地,已报道4种有尾类、1个无尾类蝌蚪、1个幼年蜥蜴、3种带原始羽毛的兽脚类恐龙、2种翼龙、3种哺乳动物以及双壳类、叶肢介、昆虫和植物等化石(有学者称之为"前热河生物群")。该层位比热河群义县组低,但地层划分存在争议:中侏罗统九龙山组、上侏罗统道虎沟组和下白垩统热河群均有报道。本文研究的道虎沟蜥蜴是该地点发现的第2个蜥蜴化石,其身体细长,为一幼年个体;前颌骨、顶骨和额骨均成对;上颌骨的面突高;后额骨和后眶骨不愈合;后额骨较大,但可能未进入上颞孔;后眶骨具宽的后突;牙齿小而尖锐,结构简单且可能为侧生;头骨的眶前区较长;具27个荐前椎;虽然未成年但个体较大;未见真皮骨板;手掌和四肢较长。上述特征组合区别于所有现生蜥蜴类,四肢比例也与其他蜥蜴有较大区别。欧美中侏罗世-早白垩世的小盗蜥(Parviraptor)和蒙古早白垩世的一个幼年个体(可能属于壁虎型类)与道虎沟标本比较相似。头骨特征和较大的荐前椎数目显示道虎沟标本可能属于硬舌蜥类(scleroglossan)。但因标本为幼年个体,本文暂将它归入有鳞类属种未定(Squamata gen.et sp.indet.)。测量数据显示,道虎沟标本的手掌和前肢相对较长;该特征常见于适应攀爬的蜥蜴种类,似可显示攀爬习性。但肢体比例可能会随身体增长而发生变化,所以此生活习性并非定论。  相似文献   

2.
道虎沟化石层分布于内蒙古宁城县道虎沟以及毗邻的河北北部和辽宁西部等地,已报道4种有尾类、1个无尾类蝌蚪、1个幼年蜥蜴、3种带原始羽毛的兽脚类恐龙、2种翼龙、3种哺乳动物以及双壳类、叶肢介、昆虫和植物等化石(有学者称之为“前热河生物群”)。该层位比热河群义县组低,但地层划分存在争议:中侏罗统九龙山组、上侏罗统道虎沟组和下白垩统热河群均有报道。本文研究的道虎沟蜥蜴是该地点发现的第2个蜥蜴化石,其身体细长,为一幼年个体;前颌骨、顶骨和额骨均成对;上颌骨的面突高;后额骨和后眶骨不愈合;后额骨较大,但可能未进入上颞孔;后眶骨具宽的后突;牙齿小而尖锐,结构简单且可能为侧生;头骨的眶前区较长;具27个荐前椎;虽然未成年但个体较大;未见真皮骨板;手掌和四肢较长。上述特征组合区别于所有现生蜥蜴类,四肢比例也与其他蜥蜴有较大区别。欧美中侏罗世-早白垩世的小盗蜥(Parviraptor)和蒙古早白垩世的一个幼年个体(可能属于壁虎型类)与道虎沟标本比较相似。头骨特征和较大的荐前椎数目显示道虎沟标本可能属于硬舌蜥类(scleroglossan)。但因标本为幼年个体,本文暂将它归入有鳞类属种未定(Squamata gen.etsp.indet.)。测量数据显示,道虎沟标本的手掌和前肢相对较长;该特征常见于适应攀爬的蜥蜴种类,似可显示攀爬习性。但肢体比例可能会随身体增长而发生变化,所以此生活习性并非定论。  相似文献   

3.
我国内蒙中侏罗世道虎沟生物群是古生物学的热点之一,报道了种类繁多的脊椎动物化石如两栖类、爬行类、哺乳动物等,特别是有尾两栖类热河螈和初螈在道虎沟数量丰富。一些学者曾经报道过道虎沟生物群中的蝌蚪化石,经过重新分析这块标本并不具备脊椎动物的骨骼构造,跗骨特征与脊椎动物差别很大而符合昆虫的跗节构造,其身体部分具有一些骨板缝,所谓的"蝌蚪"尾部其实是昆虫的喙,因而这是一块残破蝉类化石的虫体前部。虽然蛙类化石在我国下白垩统地层中并不少见,但道虎沟生物群迄今并未报道过真正的蛙类。  相似文献   

4.
晚侏罗世蜥蜴化石在世界范围内分布较为贫乏,而这个时期的化石在研究早期蜥蜴类的形态及分类演化方面具有重要意义。记述了河北北部晚侏罗世蜥蜴化石一新属种:丽热河蜥Jeholacertaformosagen.etsp.nov.,该化石保存有大面积精美的皮肤鳞片。这是蜥蜴类鳞片化石在我国的首次发现,同时也为人类认识早期蜥蜴动物的表皮特征提供了珍贵的材料。由于躯干具有较大的方鳞,该蜥蜴应隶属于石龙子次亚目Scincomorpha,似可归入蜥蜴科Lacertidae,有待证实。模式标本采自河北平泉县杨树岭镇石门村义县组下部地层中,保存于中国地质博物馆。  相似文献   

5.
辽宁中生代鸟类综述   总被引:14,自引:2,他引:12  
本文对发现于辽宁中生代地层中的鸟类化石,进行了简单的总结。化石的系统分析表明,从晚侏罗世到早白垩世在这一地区存在两个亚纲的鸟类分子:蜥鸟亚纲(Sauriurae)和今鸟亚纲(Ornithurae)。其中,蜥鸟亚纲的成员不仅数量居多,而且存在较大的分异。今鸟亚纲的分子则种类和数量都相对较少。辽西中生代鸟类的大量出现,除了鸟类自身的发展原因外,晚侏罗世到早白垩世这一地区适宜的生态环境也为鸟类的繁荣提供了必要的条件。辽西地区陆相中生代地层义县组和九佛堂组的时代分别为晚侏罗世和早白垩世。  相似文献   

6.
相对于中国和蒙古晚白垩世较知名的蜥蜴动物群,该地区古新世蜥蜴的研究非常有限。安徽潜山盆地曾报道了古新统望虎墩组和痘母组中的6种蜥蜴:中国飞蜥(Agama sinensis Hou,1974),淮南安徽蜥(Anhuisaurus huainanensis Hou,1974),短头安庆蜥(Anqingosaurus brevicephalus Hou,1976),华南长江蜥(Changjiangosaurus huananensis Hou,1976),黄铺潜山蜥(Qianshanosaurus huangpuensis Hou,1974)和痘母响蜥(Tinosaurus doumuensis Hou,1974),但化石材料均较破碎。本文使用CT扫描技术,在最新的有鳞类分类框架下对这些属种进行了重新研究,修订了上述属种的形态学特征及其分类位置。潜山盆地古新世蜥蜴动物群具有比原认为更高的形态学和生态学分异度,如巨蜥类材料(IVPP V22767)的发现和对安庆蜥可能为穴居型的新解释。  相似文献   

7.
辽宁西部晚中生代地层的综合层序为:义县组、九佛堂组、沙海组/张老公屯组、阜新组和孙家湾组.中西部朝阳—喀左—建昌以及凌源—三十家子盆地的义县组大致相当于东部阜新—义县—锦州盆地的狭义义县组及其底部的北票尖山含化石沉积夹层;中西部的九佛堂组则可与东部的金刚山、吐呼鲁和九佛堂三个岩组相对比;张老公屯组火山岩在层序上大部分可能位于九佛堂组和阜新组之间.以北票鲟、中华弓鳍鱼和狼鳍鱼为代表的鱼类化石普遍见于中国北方热河群及其相当岩群的下部河湖相地层中,以粒鳞鱼、固阳鱼和副狼鳍鱼为代表的鱼类化石多见于上部的扇三角洲和湖沼相含煤地层中.热河群及相当岩群时代的确定以及陆相侏罗—白垩系界线的厘定受制于目前地层和生物化石的研究程度.从鱼群的面貌看,义县—九佛堂组、沙海—阜新组及相当地层的时代可能分别为晚侏罗世晚期—早白垩世早期和早白垩世中期.  相似文献   

8.
辽宁葫芦岛市九怫堂组发现一批有房两栖类化石.经初步研究建立一新属种:钟健辽西螈Liaoxitritonzhongjianigenetsp.nov.,辽西爆是东亚中生代有尾两栖类的首次发现,也是中国除早中中新世中新原蝈外有尾两栖类化石的唯一报道。它代表一类小型的较原始的有尾两栖类。其头骨特征、犁骨告列形态等与小科的激Batrachuperus比较相似。辽西好的深入研究将对有尾两栖类的起源、早期演化,及其地理迁徙提供重要的信息。  相似文献   

9.
早白垩世热河生物群一新的有尾两栖类   总被引:39,自引:5,他引:34  
描述了内蒙古宁城下白垩统义县组下部一新的有尾两栖类:奇异热河螈(新属、新种)Jeholotriton paradoxus gen. et sp. nov.。标本保存了完好的相关节的骨架印痕,头骨中的翼 骨具有一个不与上颌骨相连,而与头骨中部相连的前内侧突,这使它区别于其他早期有尾类。  相似文献   

10.
张鑫  郑大燃 《古生物学报》2022,61(4):654-661
热河生物群是保存最好的白垩纪陆地生物群, 是世界上最重要的特异埋藏化石宝库之一。热河生物群的三阶段演化学说认为该生物群在第二演化阶段往南至秦岭、大别山一带, 包括河南西部和南部地区。早期研究记录表明河南西部地区产出热河生物群的代表分子三尾拟蜉蝣化石。本文首次报道了河南西部南召县马市坪盆地南召组衍蜓科稚虫化石, 并对其形态特征进行了简要描述, 同时报道了与之伴生的三尾拟蜉蝣稚虫化石。衍蜓科稚虫是热河生物群的代表化石之一, 先前均记录于辽宁西部义县组及相当地层, 属于热河生物群第二演化阶段的特征分子。河南西部新发现的昆虫化石证实了热河生物群在其第二演化阶段已经到达该地区。同时, 本研究确定马市坪盆地南召组可与辽宁西部义县组相对比, 南召组的地质时代属于早白垩世而非晚侏罗世。  相似文献   

11.
Two species of fossil insects from the Daohugou Formation of Chifeng City in Nei Monggol Autonomous Region, northeastern China are described, and recognized as Psocites pectinatus (Hong, 1983) nov. emend., nov. transl. and P. fossilis nov. sp. They are the oldest representatives of the family Callovian or Axymyiidae, and first described of this family in the Mesozoic. Although early the age of the fly-bearing beds is controversial, it is probably Oxfordian or Kimmeridgian (Late Jurassic) rather than Early Cretaceous or Middle Jurassic.  相似文献   

12.
Three new species of fossil snipe flies (Insecta, Diptera, Rhagionidae) from the Daohugou Formation of Chifeng City in Nei Monggol Autonomous Region (= Inner Mongolia), northeastern China are described as Palaeobolbomyia sinica nov. sp., Ussatchovia robusta nov. sp. and Ussatchovia gracilenta nov. sp. They represent the first records of the genera Palaeobolbomyia Kovalev and Ussatchovia Kovalev in China and have implications for stratigraphic correlation of the formations in which they are found. Although the precise age of the Daohugou Formation is currently unresolved, it is most likely Callovian-Oxfordian (latest Middle Jurassic-earliest Late Jurassic) rather than early Middle Jurassic (late Aalenian-early Bajocian) or Early Cretaceous.  相似文献   

13.
Abstract:  The largest known flying organisms are the azhdarchid pterosaurs, a pterodactyloid clade previously diagnosed by the characters of their extremely elongate middle-series cervical vertebrae. The named species of the Azhdarchidae are from the Late Cretaceous. However, isolated mid-cervical vertebrae with similar dimensions and characters have been referred to this group that date back to the Late Jurassic, implying an almost 60 million year gap in the fossil record of this group and an unrecorded radiation in the Jurassic of all the major clades of the Pterodactyloidea. A new pterosaur from the Early Cretaceous of Liaoning Province of China, Elanodactylus prolatus gen. et sp. nov., is described with mid-cervical vertebrae that bear these azhdarchid characters but has other postcranial material that are distinct from the members of this group. Phylogenetic analysis of the new species and the Pterodactyloidea places it with the Late Jurassic vertebrae in the Late Jurassic–Early Cretaceous Ctenochasmatidae and reveals that the characters of the elongate azhdarchid vertebrae appeared independently in both groups. These results are realized though the large taxon sampling in the analysis demonstrating that the homoplastic character states present in these two taxa were acquired in a different order in their respective lineages. Some of these homoplastic characters were previously thought to appear once in the history of pterosaurs and may be correlated to the extension of the neck regions in both groups. Because the homoplastic character states in the Azhdarchidae and Ctenochasmatidae are limited to the mid-cervical vertebrae, these states are termed convergent based on a definition of the term in a phylogenetic context. A number of novel results from the analysis presented produce a reorganization in the different species and taxa of the Pterodactyloidea.  相似文献   

14.
毛翅目昆虫幼虫俗称石蚕,大部分石蚕就地取材,构筑不同形状,不同质地的巢,多数为管状.石蚕巢化石是一类较重要的遗迹化石,在国外中、新生代报道较多,但在我国未见发表.本文根据作者十多年来在华北及东北地区的大量野外工作,报道了石蚕巢化石在我国的发现.介绍了石蚕巢在中侏罗世道虎沟动物群,早白垩世热河动物群及卢尚坟昆虫群中的类型与特征.石蚕巢是我国遗迹化石研究中的薄弱环节,实际上它们在中生代中期以后的陆相地层分布很广.由于这类昆虫对水质变化的敏感性和适应的相对狭隘性,可用于恢复古环境.一些特殊类型的出现,对地层对比也将起到作用.  相似文献   

15.
《Comptes Rendus Palevol》2013,12(3):159-163
A remarkable new rove beetle, Protodeleaster glaber gen. et sp. nov, is described and illustrated based on two well-preserved specimens from the Lower Cretaceous Yixian Formation of Liaoning Province, China. The new genus is placed in the extant staphylinid subfamily Oxytelinae, and recent tribe Euphaniini, based on several characteristic features (e.g. a single pair of wide paratergites on abdominal segments; open procoxal fissures; contiguous mesocoxae; abdominal sternite II short and poorly sclerotized). This find from the Early Cretaceous documents the oldest fossil representative of the tribe Euphaniini. Morphologically, it resembles most closely the recent genus Platydeleaster Schülke, 2003, an unusual member of the extant Oxytelinae. According to the currently accepted hypothesis of the phylogenetic position of Euphaniini and the prior discovery of other taxa from the Late Jurassic, we suggest the tribe might have first appeared at least as early as the Late Jurassic.  相似文献   

16.
A second basal hadrosauroid dinosaur, Zuoyunlong huangi gen. et sp. nov., is reported from the early Late Cretaceous Zhumapu Formation in Zuoyun County, Shanxi Province, northern China. Zuoyunlong preserves a partial right ilium and ischium and is unique in having a very short postacetabular process 50% as long as the iliac central plate. Our cladistic analysis recovers Zuoyunlong as the most basal Late Cretaceous hadrosauroid, with a sister taxon relationship with Probactrosaurus from the late Early Cretaceous of Inner Mongolia. Including Zuoyunlong, four Cenomanian basal hadrosauroids have been recorded, and the two taxa in North America (Eolambia and Protohadros) represent the earliest known hadrosauroids outside of Asia. In the light of the proposed phylogenetic topology and biogeographic data, the discovery of Zuoyunlong indicates that the first dispersal of hadrosauroids from Asia to North America probably happened around the boundary between the Early and Late Cretaceous.  相似文献   

17.
Javier Luque 《Palaeontology》2015,58(2):251-263
Despite the extensive fossil record of higher crabs (Eubrachyura) from Late Cretaceous and Cenozoic rocks worldwide, their Early Cretaceous occurrences are scarce and fragmentary, obscuring our understanding of their early evolution. Until now, representatives of only two families of eubrachyuran‐like crabs were known from the Early Cretaceous: Componocancridae and Tepexicarcinidae fam. nov., both monospecific lineages from the Albian (~110–100 Ma) of North and Central America, respectively. The discovery of Telamonocarcinus antiquus sp. nov. (Telamonocarcinidae) from the early Albian of Colombia, South America (~110 Ma), increases to three the number of known Early Cretaceous eubrachyuran‐like families. The ages and geographical distributions of the oldest eubrachyuran‐like taxa (i.e. Componocancridae, Telamonocarcinidae and Tepexicarcinidae fam. nov.) suggest that the oldest higher true crabs might have originated in the Americas; that they were already morphologically diverse by the late Early Cretaceous; and that their most recent common ancestor must be rooted in the Early Cretaceous, or even the Late Jurassic.  相似文献   

18.
海南岛保亭县毛感乡南兵至南好公路边南好组以往被确认为下石炭统岩关阶 ,并认为与其下的上志留统足赛岭组呈角度不整合接触。著者最近在该剖面南好组中发现兰多维列世特里奇期晚期 (LateTelychian)Xi nanospirifer腕足动物群和三叶虫Latiproetuscf.latilimbatus,证明久归于下石炭统岩关阶南好组的地质时代应改归于早志留世 (Llandoverian) ;海南岛地区在早志留世明显属于扬子地台区的范畴 ;从地质时间上还暗示南好组与其下伏的足赛岭组不可能存在角度不整合接触 ;  相似文献   

19.
西北地区潮水盆地侏罗系青土井群轮藻化石   总被引:2,自引:0,他引:2  
潮水盆地青土井群为一套含煤碎屑岩,在盆地东部潮参l井青土井群三段发育大量以Aclistochara占优势的轮藻化石群,其组合特征显示浓厚的晚侏罗世色彩。青土井群一、二段轮藻化石稀少,结合地层层序,推测其地质时代为早侏罗世。围岩沉积特征表明本井轮藻化石群为浅水生物群。  相似文献   

20.
记述了河南确山后胥山晚上新世裂隙堆积物中新发现的鲁南鼩鼱Lunanosorex材料;重新观察了内蒙古比例克的李氏鲁南鼩鼱相似种Lunanosorex cf.L.lii标本。确山鲁南鼩鼱的形态特征与属型种L.lii较为一致,其较丰富的材料为了解该种的形态变异及特征补充提供了新的依据。内蒙古比例克的鲁南鼩鼱与属型种有较大的差异,被确定为新种L.qiuisp.nov.。根据比例克新种和确山新材料的研究,修订了Lunanosorex的属征和Beremendiini族征的定义,探讨了鲁南鼩鼱与东亚地区发现的其他牙齿染色的大型鼩鼱类之间的系统关系,阐证了日本中更新世的Shikamainosorex与北美上新世的Paracryptotis关系不大,不应归入Blarrinini族,而与亚洲大陆的鲁南鼩鼱有较近的亲缘关系,应当属于Beremendiini族。  相似文献   

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