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Nesbitt SJ 《Proceedings. Biological sciences / The Royal Society》2003,270(Z2):S234-S237
The Moenkopi Formation has yielded partial and isolated remains of important archosaurs including rauisuchian skull fragments and isolated poposaur centra and pelvic girdle elements. A recently discovered skeleton referable to Arizonasaurus babbitti shows that most of these archosaurian remains belong to one taxon. Characteristics of the skeleton of Arizonasaurus show that it belongs to a poorly known group of Middle Triassic (240-230 Myr ago) archosaurs called the ctenosauriscids, and that ctenosauriscids are or are closely related to poposaurs. Furthermore, many characteristics of Arizonasaurus provide evidence that poposaurids and ctenosauriscids are derived rauisuchians. The presence of a poposaurid in the early Middle Triassic suggests that the divergence of birds and crocodiles occurred earlier than previously thought. Middle Triassic ctenosauriscids also allow the correlation of Triassic faunas in Europe, Asia, North America and Africa. The Moenkopi Formation fauna represents a transitional fauna between Early and Late Triassic faunas. 相似文献
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近30年来,巴基斯坦盐岭地区的Wargal组和Chhidru组以及在喜马拉雅地区相当地层的地质时代被许多学者视为中二叠世(瓜达鲁普世)。根据华南与盐岭地区瓜达鲁普统和乐平统的牙形类化石带对比,可以确定Amb组和Wargal组底部的时代为瓜达鲁普世晚期,瓜达鲁普统与乐平统的界线位于Wargal组下部,吴家坪阶与长兴阶的界线位于Chhidru组的下部,而二叠与三叠系的界线位于Mianwali组下部的Kathwai段之内。我国西藏南部色龙群及相当地层含有与巴基斯坦盐岭地区Kalabagh段和Chhidru组可对比的乐平世腕足动物群以及二叠系—三叠系界线附近连续的牙形类化石带,由此可以推定色龙群的时代应为乐平世。 相似文献
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Abstract: The heterodont bivalve Sinbadiella pygmaea gen. et sp. nov. is described from the Sinbad Limestone Member (Olenekian, Smithian) of the Lower Triassic Moenkopi Formation of Utah (USA). The new taxon is tentatively assigned to the Lucinidae on the grounds of its external morphology, larval shell morphology and hinge characters. It is the only definite representative of the Superorder Heterodonta in the Olenekian, removing this major clade of bivalves from the long list of Early Triassic Lazarus taxa. Although at least locally very abundant, the new taxon has been overlooked by earlier workers, probably due to its minute size. Dwarfism is a widespread phenomenon in Early Triassic faunas, which has been attributed to ongoing reduction of primary production. If S . pygmaea was a lucinid, a chemosymbiotic feeding mode can be inferred, which might explain why it was able to thrive in conditions that suppressed filter feeding heterodonts. 相似文献
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José B. Diez Jean Broutin Sylvie Bourquin Javier Ferrer 《Review of Palaeobotany and Palynology》2010,162(3):522-542
This paper focuses on the diversity and palaeontological significance of the Anisian floral record in the Triassic of the northeastern Iberian Peninsula. A summary of published information is followed by new records from macrofloral localities at Rodanas (Aragonese Branch of the Iberian Range) and at Maya del Baztán (Basque-Cantabrian Domain, Pyrenees). Both of these new localities also yielded three Anisian microfloral assemblages. These records provide new evidence of Anisian (basal Middle Triassic) floras in Spain. They are found to be somewhat similar to the classical flora of the Grès à Voltzia Formation (Upper Buntsandstein) of the northern Vosges in north-eastern France, of whose age has been shown to be early Anisian. 相似文献
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陕西铜川中三叠世原直脉蝎蛉属(昆虫纲,长翅目)新化石 总被引:2,自引:0,他引:2
本原直脉蝎蛉化石标本采自陕西铜种中三叠世铜川组下段上部(T21^2)灰绿色泥页岩,中描述2个新种,并附上产于世界各地的10个种主要特征的检索表,新种的模式标本保存在北京自然博物馆。 相似文献
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《微体古生物学报》2015,(2)
本文总结了塔里木盆地西北缘露头剖面和典型钻井(草1井与托甫2井)剖面柯坪塔格组岩电及生物特征,并在此基础上对中央隆起区32口主要钻井的柯坪塔格组进行连井地层划分对比及地震剖面标定追踪。结合对等T0图分析,探讨了研究区柯坪塔格组三段分布规律。研究表明,柯坪塔格组上段分布最广,除麻扎塔格-塘参1-顺南地区以南没有发育外,其余地区均有发育,地层厚度一般在100—300m不等,在顺托果勒地区及方1井区以北分布厚度最大,超过了300m。柯坪塔格组上段总体分布表现出南薄北厚、东西分布不均的特点。柯坪塔格组中段与柯坪塔格组下段分布局限,仅在和4-顺西1-顺南3-塔中32井以北地区有发育。柯坪塔格组中段厚度一般只有40—60m,柯坪塔格组下段厚度一般为200—300m,两者厚度均表现出南薄北厚的分布特点。 相似文献
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广西凤山、西林等地中三叠统上部双壳类分带研究* 总被引:7,自引:3,他引:4
讨论广西西部中三叠统上部的双壳类生物地层序列,建立5个化石带;并附述黔南和滇东南晚三叠世1个双壳类带.这些带自下而上为:(1) Daonella (Longidaonella) producta-D. americana 带,属晚安尼早中期;(2) D. moussoni 高峰带,属晚安尼晚期;(3) D. rieberi-D. indica 带,属早拉丁期;(4) D. kotoi-D. jilongensis 带,属晚拉丁早期;(5) Halobia subcomata-D. varifurcata带,属晚拉丁晚期;(6) H. rugosoides-H. bifurcata 带,属早卡尼期.文内简要描述了各带的主要标志化石23种. 相似文献
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Abstract The new fossil specimens of Protorthphlebia Tillyd, 1933 collected from the Middle Triassic grayishgreen mudstone and shale of the Upper part of Lower Member, Middle Triassic Tongchuan Formation ( T 2 2t ) in Tongchuan Shaanxi Province, China are reported and two new species Protorthophlebia ladinica sp.nov. and P. triassica sp.nov. are described. A key to 10 species of genus Rotorthphlebia is provided. 相似文献
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Rainer R. Schoch 《Palaeontology》2000,43(4):705-727
The status of the temnospondyl family Capitosauridae is reviewed. Only by the inclusion of the genera Mastodonsaurus Eocyclotosaurus can this group be considered monophyletic. This view is based on a range of robust characters which in combination constitute the most parsimonious hypothesis. The traditional view that Mastodonsaurus Eocyclotosaurus are sister taxa of Benthosuchus is demonstrated to be based on highly variable and/or homoplastic features, whose ancestral condition is moreover uncertain. The Capitosauridae encompasses the following successive sister groups: (1) various species of Parotosuchus (which do not necessarily form a monophylum); (2) the genera Eryosuchus Mastodonsaurus (which are probably monophyletic); and (3) a range of taxa with semi-closed or entirely closed otic notches, including the genera Wellesaurus Kupferzellia Eocyclotosaurus , and Cyclotosaurus . The closure of the otic notch, an oft-cited trend among capitosaurs, is most easily explained to have occurred only once, namely within the more advanced capitosaurids; the stratigraphical significance of this feature is, however, very limited. key words : Temospondyli, Stereospondyli, Capitosauridae, phylogeny. 相似文献
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近几十年,华北的二马营组上部地层以产出中国肯氏兽-山西鳄四足动物化石组合而闻名.最近在山西临县白道峪于上覆的铜川组一段发现了中国肯氏兽.本文描述了同一地点同一层位产出的主龙型类化石,包括一具山西鳄的部分骨架以及一些可以归入suchian的主龙类.它们是铜川组一段首次记述的主龙型类.最有鉴定特征的suchian材料包括一个大的髂骨以及一个小的、形状很奇特的、可能是跟骨的骨骼.髂骨可能可以归入一个奇异的波波龙类(poposauroid).因为中国肯氏兽与山西鳄同时出现在白道峪,表明中国肯氏兽-山西鳄组合可以向上延伸到铜川组一段.髂骨与跟骨大小悬殊,可能代表两个从未在中国肯氏兽-山西鳄组合报道过的物种.白道峪发现了特化的波波龙类,支持了波波龙类在中三叠世大量分化的观点. 相似文献
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中国陕西铜川中三叠世二叠澳蝎蛉科新属新种(昆虫纲,长翅目) 总被引:2,自引:2,他引:0
记述中国陕西铜川中三叠世1新属和1新种。化石采自铜川中三叠世铜川组下段上部灰绿色泥页岩。根据脉序特征,新属、新种应归于二叠澳蝎岭科Permochoristidae,新属种的名称为Qingochorista conjunctiva gen.et sp.nov.,属于陕西昆虫群(系中三叠世陕西生物群的一个化石门类)铜川昆虫组合的新成员。时代相当于欧洲拉丁尼期(Ladinian Stagc)。 相似文献
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ZHAO Li-Jun 《古脊椎动物学报》2008,(3)
中国已知的楯齿龙目(Placodontia)化石仅见于贵州省西南部地区,其中豆齿龙亚目(Cya- modontoidea)产自关岭地区的法郎组瓦窑段,时代为晚三叠世卡尼期;楯齿龙亚目(Placodon- toidea)产自盘县的关岭组Ⅱ段,时代为中三叠世安尼期。本文记述的豆齿龙类新属种——康氏雕甲龟龙(Clyphoderma kangi gen.et sp.nov.)产于云南富源的法郎组竹杆坡段,属中三叠世拉丁期。正型标本保存于浙江自然博物馆(编号:M 8729),其头骨高度愈合,代表一个完全成年之个体,根据以下特征明显区别于我国的Psephochelys和欧洲的Psephoderma:1)头骨枕部具3枚大型的锥状鳞;2)背甲甲片结构更为复杂,具明显的放射状沟/脊结构。到目前为止,康氏雕甲龟龙是龟龙科(Placochelyidae)中惟一的中三叠世属种,该科的其他成员全部发现于上三叠统。 相似文献
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中国已知的檐齿龙目(Placodontia)化石仅见于贵州省西南部地区,其中豆齿龙亚目(Cya-modontoidea)产自关岭地区的法郎组瓦窑段,时代为晚三叠世卡尼期;楯齿龙亚目(Placodon-toidea)产自盘县的关岭组Ⅱ段,时代为中三叠世安尼期.本文记述的豆齿龙类新属种--康氏雕甲龟龙(Glyphoderma kangi gen.et sp.nov.)产于云南富源的法郎组竹杆坡段,属中三叠世拉丁期.正型标本保存于浙江自然博物馆(编号:M 8729),其头骨高度愈合,代表一个完全成年之个体,根据以下特征明显区别于我国的Psephochelys和欧洲的Psephoderma:1)头骨枕部具3枚大型的锥状鳞;2)背甲甲片结构更为复杂,具明显的放射状沟/脊结构.到目前为止,康氏雕甲龟龙是龟龙科(Placochelyidae)中惟一的中三叠世属种,该科的其他成员全部发现于上三叠统. 相似文献
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Timo van Eldijk Gerard Goris Adam Haarhuis Jos Lankamp Herman Winkelhorst Jelle Reumer André Nel Torsten Wappler 《Pal?ontologische Zeitschrift》2017,91(2):185-194
The Palaeozoic–Mesozoic transition is characterized not only by the most massive Phanerozoic mass extinction at the end of the Permian period, but also its extensive aftermath and a prolonged period of major biotal recovery during the succeeding Middle to Late Triassic. Particularly, Anisian insect species from units of the Lower to Middle Muschelkalk from the Central European Basin are rare. The specimens described here originated from the Anisian Wellenkalk facies (Lower Muschelkalk), Vossenveld Formation of the Winterswijk quarry, The Netherlands, and from the orbicularis Member (lowermost Middle Muschelkalk, Anisian) of Esperstedt near Querfurt (Saxony-Anhalt). Thus, the described insect remains from Winterwijk and Esperstedt expand our knowledge about Middle Triassic terrestrial arthropod communities and their palaeodiversity. A new species of Chauliodites (C. esperstedti sp. nov) is introduced. 相似文献
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OSTRACODS AS MARKERS OF THE PERMIAN/TRIASSIC BOUNDARY IN THE KHUFF FORMATION OF SAUDI ARABIA 总被引:1,自引:0,他引:1
Abstract: Ostracods are described for the first time from Permian–Triassic shallow marine sediments of the Khuff Formation of central Saudi Arabia. They were collected using a modified acetolysis technique for releasing calcareous shells from limestones that is described herein. Thirty-four species belonging to 17 genera are recognized. Two new species are described: Arqoviella arabica sp. nov. and A. khartamensis sp. nov. The ostracod fauna supports a Late Permian age for the lower Khartam Member and a probable Early Triassic age for the upper Khartam Member of the Khuff Formation of central Saudi Arabia. This suggests that the Permian/Triassic boundary is located within the Khartam Member, rather than at the major lithological break between the Midhnab and Khartam members. Palaeoecological analysis suggests that the palaeoenvironment of the Khuff Formation was shallow marine (between 1 and 50 m deep) on an internal shelf. 相似文献
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贵州关岭晚三叠世一大型鱼龙类头骨 总被引:22,自引:2,他引:20
记述了产自贵州关岭上三叠统杯椎鱼龙属一新种——亚洲杯椎鱼龙(Cymbospondylusasiaticus sp. nov)。标本为两件几乎完整的头骨,产于法朗组瓦窑段的泥质灰岩中,这是目前已知惟一的晚三叠世(Cymbospondylus属的标本,也是该属时代最晚的一个种。亚洲杯椎鱼龙头部最明显的特征是下颌牙齿仅分布于齿骨的前半部分。此外,新种的吻部极长,超过头骨全长之半,上颌骨非常发达,并且具有已知鱼龙类中最小的眼眶。亚洲杯椎鱼龙是这一大型鱼龙类在北美和欧洲以外地区的首次记录。 相似文献
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贵州中三叠世早期幻龙属(Nothosaurus)一新种 总被引:3,自引:0,他引:3
作为三叠纪海生爬行动物的重要分子,幻龙属化石主要发现于欧洲、中东和中国西南地区的中三叠世海相地层,且主要集中分布于安尼期晚期和拉丁期晚期(Edinger,1921;Haas,1980;Rieppel,2000)。我国目前已报道的幻龙属化石有两种:杨氏幻龙(Li and Rieppel,2004)和幻龙属未定种(Rieppel,1998),它们均产于贵州省兴义地区的法郎组竹杆坡段,时代为中三叠世拉丁期。最近在贵州省盘县地区关岭组Ⅱ段地层中也发现了数量较多的幻龙骨骼化石,证明中三叠世早期东特提斯区同样生存着幻龙类。鉴于标本的骨骼特征与已知的幻龙属种相比存在一定的差异,因此本文建立一新种Nothosaurus rostellatus sp.nov.(小吻幻龙)。新种的个体在幻龙属种中为中等(头骨中线长210~320mm);吻部短而小,具4个前颌骨獠齿,紧随其后是第5个明显较小的前颌齿;一对上颌骨犬齿之前有6~9个小型上颌齿;眼窝较大,卵圆形,位置相对靠前;内鼻孔的后缘由腭骨构成,具内鼻槽;外翼骨形成腹向凸缘;下颌具冠状突;背椎神经棘较低,背肋肩部明显加厚。N.rostellatus与其他已知种的主要区别特征是吻部形态和比例。新种的吻部较小,长略大于宽,前端钝圆,基部明显收缩,其吻部长度(从吻端至外鼻孔前端的距离)仅占其头骨中线长度的1/6~1/7,而其他种一般占1/4~1/5,具有细长吻部的N.haasi甚至接近1/3。此外,新种吻端-上颞孔前缘距离与吻端-外鼻孔前缘距离的比值也明显高于其他种。N.rostellatus区别于其他幻龙种的另一主要特征是上颌骨牙齿的数目和排列。在已知的幻龙属种中,很少有一对上颌犬齿前的上颌齿数超过5个者。新种正型标本ⅣPPⅤ14294在一对上颌犬齿前具有6个小型锥状上颌齿,它们大小相等,指向腹方。副型标本ⅣPPⅤ14301在一对上颌犬齿前具有9个小型锥状上颌齿。在已知的Nothosaurus中,新种与N.youngi Li & Rieppel,2004和N.marchicus Koken,1893无论是个体大小还是头骨形态均比较接近,如具有相对短而宽的吻部和较短的上颌齿列、相似的鼻骨形态等,与其他种相差较大,因此这里仅对新种与此二种之间的异同做简要的介绍。从头骨的一些具体形态特征看,N.rostellatus的鼻骨后侧方与前额骨相连,阻隔了额骨和上颌骨,该特征与N.youngi相同而不同于N.marchicus,后者鼻骨受额骨与上颌骨的阻隔,不与前额骨相连。如果不考虑鳞骨的外侧分支的宽度,Ⅴ14294和Ⅴ14301与N.youngi的头骨的最宽处均位于轭骨的后端位置,且其宽度为吻部宽度的2.6~3.5倍(其中N.youngi为2.6倍,Ⅴ14294为3倍,Ⅴ14301为3.5倍),而N.marchicus的最宽处位于头骨后部鳞骨的分支处,其轭骨后缘处头骨宽度为吻部宽度的2~2.8倍(Rieppel and Wild,1996,fig.36,41)。此外,N.rostellatus外翼骨形成腹向突起和下颌具冠状突的特点也与N.youngi相同,N.marchicus不具有该特征。另一方面,N.rostellatus的枕部特征则与N.marchicus接近而不同于N.youngi。新种的枕部内凹,枕骨侧边的后耳骨等向后侧部延伸,下颌关节在头骨后部位于枕髁之后,该枕部特征与N.marchicus一致。N.youngi的下颌关节与枕髁基本位于一个平面内,因此枕部未形成明显的内凹。新种的眼眶与上颞孔之间的距离相对较宽,其中V 14294眼眶与上颞孔之间的距离与外鼻孔与眼眶之间的距离接近相等,而V 14301眼眶与上颞孔之间的距离大于外鼻孔与眼眶之间的距离。此特征也与N.marchicus相同而不同于N.youngi,前者眼眶与上颞孔之间的距离与外鼻孔与眼眶之间的距离相等,后者的眶后弓很窄,其眼眶与上颞孔之间的距离小于外鼻孔与眼眶之间的距离的1/2。N.rostellatus鼻骨的左右两前突分别伸至两外鼻孔的前缘内侧,位置与N.marchicus相同,而N.youngi鼻骨前突仅伸至外鼻孔内侧缘的中部。N.rostellatus前颌骨的背突向后伸至外鼻孔后缘之后,接近鼻骨的后缘,而N.youngi仅伸至外鼻孔后缘中间部位。除前文所述新种两个主要鉴定特征外,N.rostellatus又以具有内鼻槽,翼骨前伸至内鼻槽附近等特征与该已知二种相区别。此外,新种前颌骨具外侧支突起,其他种该特征多不明显,如N.jagisteus不存在前颌骨外侧支突起,其前颌骨在外鼻孔的前外侧缘沿前外侧方向与上颌骨相交(Rieppel,2001)。从地理分布和地层层位看,N.marchicus主要分布于欧洲中部的中三叠统安尼阶,而N.youngi则分布于我国贵州南部的中三叠统拉丁阶。本文描述的化石产于贵州南部关岭组Ⅱ段,其时代应相当于中三叠世晚安尼期。N.rostellatus与分布于欧洲的同时期的幻龙N.marchicus以及与在其后约7~8Ma相邻地区出现的M.youngi的亲缘关系的远近可能还需要更深入的研究来证实。 相似文献