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1.
新疆巴里坤三塘湖志留纪三叶虫 总被引:1,自引:0,他引:1
新疆巴里坤三塘湖晚志留世阿苏山组三叶虫包括Ananaspis fecunda Barrande,Cheirurus barkolensis sp.nov.和Pacificurus sp.,与准噶尔盆地西北部乌图布拉格,哈萨克斯坦及捷克波西米亚的晚志留世三叶虫关系密切。另外对中国5个地区晚志留世三叶虫地层作了对比。Ananaspis,Pacificurus二属在中国是初次发现。 相似文献
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本文描述的腹足类是中国科学院南京地质古生物研究所西南队志留系分队的同志采集的,化石主要采自黔东和滇东地区,也包括少数川北和陕南的标本,共有15属16种,其中2新种。由于这些标本的壳饰大部分已破损,多数呈内核保存,因此有的化石暂时只能给以属名, 相似文献
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论志留纪王冠虫Coronocephalus Grabau 总被引:1,自引:0,他引:1
一、前言本文以简单的统计方法对属于王冠虫类的34种进行对比,结果表明,至少可以识别两个组合,第一组合称王冠虫亚属组合,第二组合称王冠盾壳虫亚属组合。其中Senticucullus Xia, 1974, Coronocephalus (Coronocephalina) Wu, 1979和Coronocephalus Grabau,1924,3属或亚属是同物异名,前两名应予废弃。本文新建一亚属Coronocephalus (Coronaspis) Subgen. nov.(王冠盾壳虫),模式种为Coronocephalus changningensis。这一亚属地质历程较长,在王冠虫亚属的种发生之前就已出现,并可延续到秀山“期”之后。 相似文献
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根据贵州东部晚寒武世早期地层内获得的刺尾虫科三叶虫新材料,论述了具有尾侧刺和不具尾侧刺的此类三叶虫共同起源于褶颊虫目的Mapaniidae,以及它们的早期演化,此外,还描述了此类三叶虫1新亚属、2新种和2新亚种及其个体发育过程中的一些变异,对于正确认识寒武纪三叶虫的分类,演化具有一定的意义。 相似文献
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对滇东镇雄羊场桃子崖(北纬27°36′53″,东经104°37′42″)和芒部刘家沟(北纬27°36′22″, 东经104°52′30″)早奥陶世晚期湄潭组下部所产Omeipsiszhenxiongensis Luo, 1974新材料作了研究,得以揭示Omeipsis Kobayashi, 1951的完整形态特征.该属除尾部具有一长一短两对边缘刺外,其头鞍向前逐渐扩张并发育有粗壮前刺.RenhuaiaYin in Yin and Li, 1978应为Omeipsis的晚出异名,因为两者头盖并无显著差异. 相似文献
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研究材料系自浙江江山晚奥陶世黄泥岗组硅质结核中的Telephina convexa Lu眼部内模和外模标本。使用SEM二次电子图像把眼部放大,发现其小眼体是透镜体,外形为正八角形的透镜体,正八角形的每一相间的部位为正方形的眼间体(interlens)所占据,它们填充在八角形小眼体顶角和底角外侧的空间。每一正八角形的边长为66.66μm,小眼体之间为四向两组垂直交叉排列。Telephina的眼是介于在叶虫复眼和聚合眼之间的一种特殊类型的眼。从眼的构造和形态来看,Telephina 应属于中远洋悬浮类三叶虫,与Cyclopyge近似。 相似文献
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描述上扬子区鄂西和湘西中及晚奥陶世桨肋虫类三叶虫Hexacopyge的 5个种 ,包括 2新种 ,即H .turbiniformis和H .yichangensis;讨论Hexacopyge的定义及其与相关属的关系。Hexacopyge在区内分布广、演化快 。 相似文献
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峡东地区寒武纪三叶虫Palaeolenus的新材料 总被引:2,自引:2,他引:2
对采自峡东地区宜昌、秭归等地的Palaeolenus Mansuy,1912的新材料的形态、保存状态、挤压变形以及个体发育等方面的研究,提出Megapalaeolenus Chang,1966的模式种Palaeolenus deprati Mansuy。1912是Palaeolenus Mansuy的模式种Palaeolenus douvillei Mansuy,1912的晚出异名,属名Mega palaeolenus Chang和种名Palaeolenus deprati Mansuy均应予以废弃。文中还对原归于Palaeolenus和Megapalaeolenus的种作较大的归并和修订。 相似文献
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华南志留纪特列奇期喙壳类新材料 总被引:1,自引:0,他引:1
喙壳纲(Rostroconchia)是Pojeta,Runnegar,Morris和Newell于1972年正式建立的软体动物门的一个纲。根据已有的材料,它们只生存于古生代的海洋中,从早寒武世出现,至晚二叠世绝灭,至今尚未有关于三叠纪喙壳类的确切报道。对现今被归于这个纲的化石的描记,至少已经有150年以上的历史。但是由于对这类化石的特征认识不足,长期以来其分类位置没有被确定。许多研究者往往根据其一般形态,将个体小、时代较老的原始类型归于节肢动物,而将其较进化的类型作为双壳类化石进行研究,或者作为分类位置未定但具有特殊形态特征的软体动物来处理。 相似文献
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记述了采自鄂西地区早志留世Llandovery(Aeronian)的三叶虫Aulacopleura(Aulacopleura)wulongensis Wang的个体发育。运用分支分析研究了深沟肋虫亚科(Aulacopleurinae)各种的最佳聚类,确定该亚科目前仅含Aulacopleura一属,Songkanina属是Aulacopleura(Paraulacopleura)亚属的同物异名。Aulacopleura一属的祖先种为A.szechuanica,在系统演化中存在幼型形成和过型形成两种异时发育现象,Aulacopleura (Paraulacopleura) 各种为该祖先种的幼型形成后裔,而Aulacopleura(Aulacopleura)各种为它的过型形成后熵。 相似文献
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《Palaeoworld》2022,31(2):239-248
The age of the Silurian “Lower Red Beds” (LRBs), which occur widely in South China, has long been controversial because of the scarcity of index fossils. Here, we report a fauna with abundant trilobites from the LRBs in Wuhan, Middle Yangtze region, consisting of Aulacopleura (Paraaulacopleura) pijiazhaiensis, ‘Encrinuroides’ yichangensis, Gaotania hubeiensis, Hyrokybe gaotanensis, Japonoscutellum yichangense, Latiproetus latilimbatus, and Ptilillaenus lojopingensis. These trilobites are common in the Leijiatun, upper Xiangshuyuan, Shihniulan, and Lojoping formations in the Upper Yangtze region, and belong to the middle to upper Aeronian Ptilillaenus or ‘Encrinuroides’–Ptilillaenus–Latiproetus assemblages. The discovery of this trilobite assemblage suggests that the LRBs are probably partly of middle–late Aeronian age in the Middle Yangtze region. Thus, the lower boundary of the LRBs is likely diachronous in the Yangtze region, ranging from the middle–late Aeronian to the early Telychian. The discovery of the Ptilillaenus assemblage in the Wuhan LRBs expands the paleogeographic distribution of this assemblage and provides evidence of deeper depositional environment of the LRBs in the study area versus shallow waters in other areas of the Yangtze region. 相似文献
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Petr Štorch Štěpán Manda Zuzana Tasáryová Jiří Frýda Leona Chadimová Michael J. Melchin 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2018,51(3):357-388
The current Global Stratotype Section and Point (GSSP ) for the Aeronian Stage (Llandovery Series, Silurian System), on Trefawr track in the Llandovery area of Wales, is an inadequate marker for precise, global, correlation. The International Subcommission on Silurian Stratigraphy has, therefore, undertaken the selection of a new GSSP for this level. The lowest occurrence of the graptolite Demirastrites triangulatus , 1.38 m above the base of the black‐shale succession of the ?elkovice Formation at the Hlásná T?ebaň section in Central Bohemia, is proposed to mark the base of the Aeronian Stage. The section, which fulfils all formal requirements for stratotype of a chronostratigraphical unit, should be considered as a candidate for the new GSSP . An abundant, well‐preserved, diverse graptolite fauna occurs through the section along with common chitinozoans, which indicate that the Spinachitina maennili Biozone spans the boundary interval. The section comprises the lower–middle Aeronian (D. triangulatus–Lituigraptus convolutus graptolite biozones) along with underlying Rhuddanian (Akidograptus ascensus–Coronograptus cyphus biozones) and Hirnantian strata. Several graptolite genera of primary importance in global correlation (Demirastrites , Petalolithus , Rastrites and Campograptus ) first appear in the lower part of the triangulatus Biozone. The structurally simple section is somewhat condensed, but there is a uniform succession of black shale without any evidence of disconformity in the broad boundary interval. The Corg isotope record exhibits a minor positive excursion just above the base of the triangulatus Biozone, whereas TOC and N isotope and elemental geochemical records provide evidence for uninterrupted sedimentation under stable, anoxic conditions. 相似文献
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湘西溶溪组的棘鱼化石及其层位 总被引:4,自引:1,他引:4
本文介绍了目前我国最低含鱼化石地层,即湘西早志留世(Llandovery 期)溶溪组的地区性地质剖面和产自该组七个类型的棘鱼鳍刺化石,并根据其同层中所产的无脊椎动物化石论证鱼化石层的层位.鱼化石本身所表现出的原始特性与这一结论是谐调的. 相似文献
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SAMUEL T. TURVEY 《Palaeontology》2005,48(3):519-547
Abstract: Faunal composition of South Chinese Arenig benthic trilobite associations is investigated using the multivariate techniques of TWINSPAN, DCA and seriation. Eight fairly distinct benthic associations can be differentiated, organized primarily along a palaeobathymetrical gradient across the Yangtze Platform in southern Shaanxi and western Hubei and the Jiangnan Transitional Belt in northern Hunan: the Taihungshania , Neseuretus , Trinucleid and Asaphid- Pseudocalymene associations (shallow shelf), the Asaphid-Raphiophorid and Nileid-Asaphid associations (< 100 m outer shelf), the Nileid-Illaenid Association (deep outer shelf carbonates) and the Pseudopetigurus Association (deep outer shelf clastics). The highest levels of diversity are displayed by the Asaphid-Raphiophorid Association of western Hubei. Investigation of the biogeographical affinities of this fauna indicates that South China is biogeographically closest to the other Chinese geotectonic units, and displays strong faunal connections to other central and eastern Asian regions as well as to Tethyan and South American regions. Subdivision of the South Chinese trilobite fauna into different depth zones shows a statistically significant correlation between increasing water depth and increasing faunal cosmopolitanism, although taxa endemic to China or Gondwana also occur even in slope faunas. The results of this biogeographical analysis are consistent with a tropical or subtropical peri-Gondwanan association of South China with other Asian terranes. 相似文献
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湘西早志留世溶溪组无颌类的发现及其意义 总被引:4,自引:5,他引:4
本文记述了在湖南西部早志留世 Llandovery 期溶溪组发现的多鳃鱼目—新科——大庸鱼科 (Dayongaspidae fam. nov), 其标本代表了中国迄今为止地质时代最早的海生早期脊椎动物化石,并进而论证了中国的盔甲鱼类发生在近岸浅海地区,而不是大陆淡水盆地,其时代为前早志留世.扬子区是这类无颌类的发源地. 相似文献
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A new trilobite, Longaspis paiwuensis n. gen. n. sp., from the Balang Formation (Cambrian Stage 4) in northwestern Hunan, South China, is described. This rare trilobite adds to an expanding taxonomic list of organisms recognized from the Balang Lagerstätte, a deposit of exceptional preservation from the Cambrian. Longaspis paiwuensis is an unusually large-sized, micropygous oryctocephalid trilobite that has proparian facial sutures, pit-like lateral glabellar furrows, up to 17 thoracic segments, and a distinct medial notch in the pygidium; it lacks marginal spines.The classification of the family Oryctocephalidae is reviewed. Three subfamilies are recognized, and Longaspis n. gen. is assigned to the subfamily Oryctocarinae. 相似文献
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西秦岭是开展华南板块志留/泥盆系界线层序研究的一个重要地区.该区普通沟剖面中的志留/泥盆系过渡带包括羊路沟组上部和下普通沟组下部,产丰富的鱼类微体化石,包括花鳞鱼类、棘鱼类、软骨鱼类及盾皮鱼类.这些化石构成两个完全不同的鱼类微体化石组合:羊路沟组合和下普通沟组合.通过与波罗的海等地区鱼类微体化石带的对比,羊路沟和下普通沟组合的地质时代分别为志留纪普里道利世晚期和早泥盆世洛霍考夫期早期.西秦岭地区志留/泥盆系过渡带中的鱼类微体化石及其组合序列的研究,为该区志留/泥盆系界线的精确确定提供了重要的古鱼类学证据. 相似文献
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描述采用自南澳大利亚Officer盆地东部Manya-6号钻井的下寒武统Ouldburra组的Abadiella三叶虫的一新种-Abadiella officerensis,同时指出Parabadiella是Abadiella的同义名。 相似文献