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1.
兰州盆地早第三纪植物及古气候意义   总被引:10,自引:0,他引:10  
化石采自甘肃省兰州盆地咸水河组底部,经研究认为有29种,归属20属12科。它们是:樟科Lauraceae (Daphnogene),木通科Lardizabalaceae(Akebia),小檗科Berberidaceae(Berberis),榆科Ulmaceae(Planera,Ulmus,Zelkova),桦木科Betulaceae(Alnus,Carpinus),杨梅科Myricaceae(Myrica),杨柳科Sali-caceae(Populus,Salix),紫金牛科Myrsinacese(Ardisia),蔷薇科Rosaceae (Prunus,Sorbus,Sorbaria,Spir-aea),豆科Leguminosae(Gleditsia,Sophora),漆树科 Anacardiaceae(Rhus),忍冬科Caprifoliaceae(Viburnum)等。经植物区系组成与叶相分析显示,该植物区系的大多数成员是落叶阔叶乔、灌木,少数为常绿灌木。其中特殊的分子是 Rhus turcomanica Korov.ex Vassilvesk,该成分是早第三纪中、晚期的标志化石植物。另一化石植物 Sorbaria callicomifolia Kornilova曾出现在中亚的早渐新世,最晚至早中新世。同一层位采集的孢粉样分析结果显示:该组合仅约20种,种类相对贫乏,并以被子植物的花粉占优势。其中出现裸子植物的麻黄粉,被子植物的白刺粉及蒿粉等,这几个类型均指示沉积时期经历干旱气候。综合植物大化石及孢粉分析研究,均出现一些指示气候为亚热带干旱或周期性干旱气候的特点,并据Rhus turcomanica出现的最晚记录,推测咸水河组底部的地质时代大约是早渐新世晚期。  相似文献   

2.
    
Recent paleobotanical investigations in Vietnam provide a good opportunity to improve our understanding of the biodiversity and paleoclimatic conditions in the geological past of Southeast Asia. Palms (Arecaceae) are a diverse family of typical thermophilous plants with a relatively low tolerance for freezing. In this study, we describe well-preserved fossil palm leaves from the Oligocene Dong Ho Formation of Hoanh Bo Basin, northern Vietnam. Characters of the fossil leaves, such as a fan-shaped costapalmate lamina, an unarmed petiole, a costa slightly enlarged at the base that then tapers distally into the blade, and well-preserved amphistomatic leaves with cuticles, suggest that they represent a new fossil species, which we herein designate Sabalites colaniae A. Song, T. Su, T. V. Do et Z.K. Zhou sp. nov. Together with other paleontological and palaeoclimatic evidence, we conclude that a warm climate prevailed in northern Vietnam and nearby areas during the Oligocene.  相似文献   

3.
记述了一段属于Allacerops of. A. turgaica幼年个体的下颌骨。化石采自甘肃兰州盆 地渐新世地层中。Allacerops 是亚洲一类较原始的犀。在基本特征上,特别是在门齿和犬齿构 造上,它和欧洲的Eggysodon最为接近,有人把它们合为一属。研究表明,它们在门齿的数目 和颊齿的形态上有比较明显的差异,应是跑犀科内不同的属。文中主要根据犀类门齿、犬齿的 分异,对犀超科内科一级的现行划分提出质疑,认为Indricotheriidae科的地位应予恢复,跑犀 科只应包括那些门齿、犬齿未特化,也不急剧退化的中、小型犀类。这样,除两栖犀外,犀超科 包括三科: Hyracodontidae,Indricotheriidae和Rhinocerotidae。  相似文献   

4.
甘肃兰州盆地咸水河组下红泥岩中的小哺乳动物化石   总被引:4,自引:1,他引:4  
兰州盆地咸水河组下红泥岩共产有15属25种哺乳动物化石。位于下红泥岩中部的峡沟和上西沟等地产有11属20种化石(Amphechinus cf. A. rectus, A. cf. A. minimus, Amphechinus sp., Soricidae indet., Sinolagomys kansuensis, S. cf. S. major, Yindirtemys grangeri, Y. xiningensis, Y. ambiguus, Eucricetodon sp., Tachyoryctoides? sp., Parasminthus asiae朿entralis, P. tangingoli, P. parvulus, Parasminthus spp., Sinosminthus sp., Heterosminthus lanzhouensis, Litodonomys huangheensis和Didymoconus berkeyi),被称为峡沟动物群。其中8属11种与党河Taben朾uluk动物群共有。两者的时代大致相当,为晚渐新世。位于瞿家川附近的下红泥岩下部产有:Desmatolagus cf. D. gobiensis, Ordolagus sp.,Tataromys plicidens, Tsaganomys altaicus, Amphechinus cf. A. minimus和Sinolagomys kansuensis等。该动物群的面貌显得比峡沟动物群的要老,而与其下的黄砂岩中所产的南坡坪动物群较相似,其时代有可能为早渐新世晚期。如果更多的化石证明是这样,那么在兰州盆地同一时代的同一动物群可产于不同的岩层(黄砂岩和下红泥岩下部),而代表不同时代的不同的动物群产于同一岩性地层中。早、晚渐  相似文献   

5.
    
<正> A locality yielding middle Tertiary mammalian fossils was discovered by a group of students in 1986. The locality is situated 1 km south of the railway station of Lanzhou, the capital of Gansu Province. It is on the northern slope of the Gaolan mountain, which is constituted basically by continental red beds capped by thick layer of loess. The red beds consists mainly of dark red gypsiferous claystone and siltstone, intercalated with comparatively thin layers of pale-yellow sandstones. The fossils were found in the upper part of the section which is almost 400m thick (fig. 1).From points of view of both vertebrate paleontology and biostratigraphy, the discovery is of great importance, and worthy of describing as early as possible.  相似文献   

6.
甘肃兰州盆地咸水河组下段红色泥岩中的跳鼠化石   总被引:2,自引:4,他引:2  
兰州盆地咸水河组下段上部红色泥岩共产有4属8种跳鼠:Parasminthus  asiae-centralis, P. tangingoli. P. parvulus Parasmintus. sp. I, Parasmintus sp. II,黄河简齿鼠(新属、种)Litodonomys huangheensis gen.et sp.nov、,兰州异蹶鼠(新种)Heterosminthus lanzhouensis sp.nov.和Sinosminthus sp。Lilodonomys,huangheensis的主要特征是颊齿比例上较宽短,冠面结构较简单,脊较发育,下中脊短或无,下外脊直接由下原尖伸出。Hetersminthus lanzhouensis为Heterosminthus属的一较原始的种。它的臼齿的颊、舌侧主齿尖虽错位,但幅度还较小,M1/2具原小尖,但无原附尖,ml具发达的下中脊,下外脊折线形,下外中脊向前倾等。 兰州盆地下红泥岩所产跳鼠组合基本上与甘肃省党河流域Taben-buluk的一致。它们的时代可能大致相当,为晚渐新世。 本文用 PAUP3.1.1对早第三纪的各跳鼠属间的关系作了分析和讨论。 跳鼠在?  相似文献   

7.
内蒙古地区中新世木化石及古气候意义   总被引:2,自引:0,他引:2  
木化石采自内蒙古赤峰平庄煤矿。矿区内展布的地层有两套,下部为晚中生代含煤地层,上部为第三系。木化石打自上部第三系,同层具有丰富的叶部化石。现报道的木材化石共3种,平庄原始黄杉型木Pseudotsugaxylon pingzhangensis sp.nov.,东北云杉木Piceaxylon manchuricum Sze和松型木Pinuxylon sp.等。其中的原始黄杉型木的最近亲缘属黄杉属。就生  相似文献   

8.
The study of abundant permineralized fern remains collected in the Oligocene Rancahué Formation (Neuquén Province, Argentina) allowed the identification of two different taxa. The name Cuyenopteris patagoniensis nov. gen., nov. sp. is proposed for several stems and fronds characterized by the presence of caulinar dictyosteles with root gaps, producing C-shaped leaf traces composed by two hippocampiform bundles flanked by eight to ten small round bundles, half of them diverging from cauline meristeles and the rest from the hippocampiform bundles. The presence of these features, along with frond bases with adaxial grooves and a pair of pneumatophores, suggest affinities with the Blechnaceae or Dryopteridaceae. The second identified taxon is Alsophilocaulis calveloi Menéndez. Based on features observed in these new materials, including characteristics of the mantle of adventitious roots and anatomy of the petiole bases, an emended diagnosis for this latter species is proposed.  相似文献   

9.
记述了首次发现于柴达木盆地早渐新世晚期至晚渐新世早期(距今27~29 Ma)的鲤科鱼类化石。材料包括咽骨、咽齿、匙骨、腹鳍骨及一些零散的鳍条。咽骨及咽齿化石与原始鲃亚科鱼类及裂腹鱼亚科裂腹鱼属鱼类的相似;腹鳍骨化石与原始鲃亚科鱼类的更相似。鲃亚科鱼类现今分布于北纬35°以南的亚洲、欧洲南部及非洲北部;裂腹鱼属鱼类分布局限于青藏高原东、南、西面的边缘区域,在柴达木盆地没有分布。柴达木盆地水系现生鱼类仅见适于高寒环境的高度特化等级的裂腹鱼亚科鱼类及鳅科高原鳅属鱼类,鱼类组成与早渐新世晚期至晚渐新世早期的不尽相同。  相似文献   

10.
Petrified woods obtained from the Oligocene of Tsuyazaki, Fukuoka Prefecture have been studied, and four new species ofPrunus (Rosaceae) are described:Prunus palaeozippeliana, P. ascendentiporulosa, P. uviporulosa andP. polyporulosa. These four species are very similar to each other in gross anatomical features and are characterized by the diffuse porosity, exclusively simple perforation plates, spiral thickenings on vessel walls, heterogeneous rays and the presence of traumatic gum canals. The petrified woods ofPrunus are new records from the Tetiary of Japan.  相似文献   

11.
对采自四川盆地云阳一带自流井组东岳庙段14属18种植物化石进行了研究,其中描述1个新种Stachypteris? anomala Meng(sp.nov.)和1个首见于区内的种Klukia exilis(Phillips)。东岳庙段植物组合的重要分子是从下伏珍珠冲段延续而来的,这表明此组合基本承袭了珍珠冲段的组合面貌。依据Dictyophyllum nilssoni,D.nathorsti,Otozamites hsiangchiensis等尚未见于中侏罗世和自流井组明显分为两大沉积旋回,指出东岳庙段的时代属早侏罗世托尔期(Toarcian)和四川盆地下-中侏罗统的界线以划在自流井组东岳庙段与马鞍山段之间为宜。  相似文献   

12.
    
This paper reports fossil plants from Xingyuan Formation, Pingzhuang Chifeng, Nei Monggol of China. The relationships between this flora and Fuxin Formation are discussed. We have also considered the relationship between this flora and the Japanese Late Jurassic flora. Meanwhile, We have described the new species-Ginkgoites pingzhangensis, and studied its cutical under both optical microscope and scanning electron microscope.  相似文献   

13.
Two complete humeri of Aegyptopithecus zeuxis have been recovered from Oligocene deposits in the Fayum Province of Egypt. These new specimens support previous interpretations of the locomotor adaptations of this species and indicate that A. zeuxis was a robust, slowly moving arboreal quadruped. While the previously described distal articular region of the humerus is virtually identical with the same region in many extant ceboids and the Miocene hominoid Pliopithecus vindobonensis, the more proximal parts of the humerus show many primitive "prosimianlike" features not found the limbs of extant anthropoids. The primitive features include the absence of a distinct deltoid plane, a broad shallow bicipital groove, a large brachialis flange, and an entepicondylar foramen. In most features, the humerus of Aegyptopithecus zeuxis is more primitive than the hypothetical last common ancestor of extant cercopithecoids and hominoids based on neontological comparisons. This supports other lines of evidence indicating that the hominoids from the Egyptian Oligocene are morphologically ancestral to both Old World monkeys and apes.  相似文献   

14.
记兰州盆地第三纪中期的爪兽(奇蹄目)化石   总被引:2,自引:1,他引:2  
记述了兰州盆地新发现的三种爪兽化石:Schizotheriumordosium,Phyllotillonhuangheensissp.nov.和Chalicotheriinae亚科未定属种的一类。在咸水河组下段南坡坪地方动物群(早渐新世晚期)中发现S.ordosium。这个种的材料较多,其中有保存完好的下颌吻部。这使我们第一次了解了这个属的吻部的构造:吻部很长、具大的铲形下门齿和双叶形的下犬齿.在咸水河组中段(早中新世)张家坪地方动物群中发现了Phyllotillonhuangheensis和Chalicotheriinaegen.etsp.indet。前者比巴基斯坦Bugti层中的P.naricus个体稍小,形态上也更原始些。这可能表明,张家坪地方动物群在时代上比Bngti稍早。后一类爪兽的性质还不很清楚,但Chalicotheriinae亚科在我国早中新世的出现则无疑义。  相似文献   

15.
Paraceratherium在新疆准噶尔盆地北缘的发现及其意义   总被引:1,自引:2,他引:1  
20 0 0年 ,笔者在位于新疆准噶尔盆地北缘的福海县哈拉玛盖乡以南的萨尔多依腊地区测制乌伦古河组地层剖面时 ,在乌伦古河组和索索泉组之间的一套粗碎屑岩层中发现了一些哺乳动物化石。其中有孟津在 2 0 0 0 4化石点 ( 4 6°3 5.779′N ,87°43 .81 8′E)发现的一具副巨犀下颌骨。该下颌保存了这类动物的一些重要特征 ,这些特征对于解决长期以来人们对于巨犀分类的有关争论以及含化石地层的时代提供了重要信息。新疆萨尔多依腊的巨犀下颌支和牙齿的形态与Forster Cooper( 1 91 1 :p .71 3 ;1 92 4:Fig .7)描述的Bugti的Paraceratheriumbu…  相似文献   

16.
Gerald Mayr 《Geobios》2006,39(6):865
A postcranial skeleton of a small bird from the early Oligocene locality Pichovet in Southern France is described and identified as Eocuculus cf. cherpinae Chandler, 1999. It is the second fossil record of Eocuculus which was hitherto known from a postcranial skeleton from the late Eocene of North America only. Although Eocuculus shares some derived similarities with Cuculidae (cuckoos), it distinctly differs in a number of osteological features from crown group members of this taxon. If future, more complete skeletons prove its cuculiform affinities, Eocuculus is a stem lineage representative of this taxon and not within the crown group. Recognition of Eocuculus in the early Oligocene of France provides evidence for the presence of an extinct late Eocene/early Oligocene avian taxon with an intercontinental Northern Hemisphere distribution.  相似文献   

17.
详细描述了采自新疆准噶尔盆地北缘铁尔斯哈巴合陡坎晚渐新世一刺猬的耳区岩骨结构。晚渐新世地层为该地区的新发现,描述的刺猬岩骨有以下特征:岬内侧面具岩骨前鼓突,腹面具岬动脉与镫骨动脉留下的沟痕,岩骨后鼓突发育并掩盖蜗窗,弓形小窝深大,乳状小突发育。岩骨的某些特殊特征可以用来鉴定某些哺乳动物类群,因此具有系统分类及生物地层意义。  相似文献   

18.
新疆准噶尔盆地北缘晚渐新世睡鼠化石的发现   总被引:1,自引:4,他引:1  
在新疆准噶尔盆地北缘富蕴县境内乌伦古河北岸铁尔斯哈巴合北的原乌伦古河组中发现了中国境内迄今为止最早的睡鼠化石Glirulus sp和Gliridae gen-et sp. indet。前者以三枚臼齿M2、M3和ml为代表,后者仅拥有一枚P4。依共生动物群的组成和性质其时代应为晚渐新世。  相似文献   

19.
甘肃临夏盆地的渐新世巨犀化石   总被引:3,自引:2,他引:3  
描述了 2种巨犀化石 :霍尔果斯准噶尔巨犀 (Dzungariotheriumorgosense)和牙沟副巨犀(新种 ) (Paraceratheriumyagouensesp .nov.)。新种的主要特征是 :个体小 ;上颊齿齿冠高 ,有薄层白垩质覆盖 ;DP2~M1反前刺大 ,原尖后收缩沟明显 ,次尖有深的前收缩沟 ,中谷和后凹中常有附属小柱等。巨犀的演化历史可能比过去想象的更复杂。Indricotherium、Dzungariotherium和Paraceratherium为代表不同进化水平和支系的 3个属 ,不应合并为Paraceratherium一属。牙沟含巨犀化石层位的地质时代为晚渐新世。  相似文献   

20.
    
Extant snake faunas have their origins in the mid-Cenozoic, when colubroids replaced booid-grade snakes as the dominant species. The timing of this faunal changeover in North America and Europe based on fossils is thought to have occurred in the early Neogene, after a period of global cooling opened environments and made them suitable for more active predators. However, new fossils from the late Oligocene of Tanzania have revealed an early colubroid-dominated fauna in Africa suggesting a different pattern of faunal turnover there. Additionally, molecular divergence times suggest colubroid diversification began sometime in the Paleogene, although the exact timing and driving forces behind the diversification are not clear. Here we present the first fossil snake referred to the African clade Lamprophiinae, and the oldest fossil known of Lamprophiidae. As such, this specimen provides the only potential fossil calibration point for the African snake radiation represented by Lamprophiidae, and is the oldest snake referred to Elapoidea. A molecular clock analysis using this and other previously reported fossils as calibration points reveals colubroid diversification minimally occurred in the earliest Paleogene, although a Cretaceous origin cannot be excluded. The elapoid and colubrid lineages diverged during the period of global warming near the Paleocene-Eocene boundary, with both clades diversifying beginning in the early Eocene (proximate to the Early Eocene Climate Optimum) and continuing into the cooler Miocene. The majority of subclades diverge well before the appearance of colubroid dominance in the fossil record. These results suggest an earlier diversification of colubroids than generally previously thought, with hypothesized origins of these clades in Asia and Africa where the fossil record is relatively poorly known. Further work in these regions may provide new insights into the timing of, and environmental influences contributing to, the rise of colubroid snakes.  相似文献   

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