• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Systematic Palaeontology >The oldest known metriorhynchid super-predator: a new genus and species from the Middle Jurassic of England, with implications for serration and mandibular evolution in predacious clades
【24h】

The oldest known metriorhynchid super-predator: a new genus and species from the Middle Jurassic of England, with implications for serration and mandibular evolution in predacious clades

机译：已知的最原始的食肉动物超级掠食者：来自英格兰中侏罗世的新属和种，对早熟进化枝的锯齿和下颌进化有影响

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The Oxford Clay Formation of England has yielded numerous sympatric species of metriorhynchid crocodylomorphs,although disagreement has persisted regarding the number of valid species. For over 140 years teeth reminiscent of the genus Dakosaurus have been known from the Oxford Clay Formation but these have never been properly described and their taxonomy and systematic affinity remain contentious. Furthermore, an enigmatic mandible and associated postcranial skeleton discovered by Alfred Leeds in the Fletton brick pits near Peterborough also remains undescribed. We show that this specimen, and several isolated teeth, represents the oldest known remains of a large-bodied predatory metriorhynchid. This material is described herein and referred to Tyrannoneustes lythrodectikos gen. et sp. nov. This species has a unique occlusal pattern: the dentition was arranged so that the posterior maxillodentary teeth interlock in the same plane and occlude mesiodistally. It is the first described crocodylomorph with microscopic denticles that are not contiguous along the carinae(forming short series of up to 10 denticles) and do not noticeably alter the height of the keel. Additionally, the dorsally expanded and curved posterior region of the mandible ventrally displaced the dentary tooth row relative to the jaw joint facilitating the enlargement of the dentition and increasing optimum gape. Therefore, Tyrannoneustes would have been a large-bodied marine predator that was well-suited to feed on larger prey than other contemporaneous metriorhynchids. A new phylogenetic analysis finds Tyrannoneustes to be the sister taxon to the subclade Geosaurini. An isolated tooth, humerus, and well-preserved mandible suggest a second species of metriorhynchid super-predator may also have lived in the Oxford Clay sea. Finally, we revise the diagnoses and descriptions of the other Oxford Clay metriorhynchid species, providing a guide for differentiating the many contemporaneous taxa from this exceptional fossil assemblage.
机译：英格兰的牛津黏土地层已经产生了许多同伴性的同伴性鳄类，尽管在有效种类的数量上仍然存在分歧。超过140年以来，牛津粘土地层就让人联想到达科龙属的牙齿，但至今仍未对其进行恰当的描述，它们的分类学和系统的亲和力仍然存在争议。此外，由阿尔弗雷德·利兹（Alfred Leeds）在彼得伯勒（Peterborough）附近的弗莱顿（Fletton）砖坑中发现的神秘的下颌骨和相关的颅后骨骼也仍未描述。我们表明，该标本和几颗孤立的牙齿代表了一个大型猛禽掠食性胸腺的最古老的已知遗骸。该材料在本文中进行了描述，并被称为Tyrannoneustes lythrodectikos gen。等。十一月该物种具有独特的咬合模式：排列的牙列使上颌后牙在同一平面内互锁，并近中部咬合。它是第一个描述的鳄鳄，具有微小的齿状体，沿着鼻甲不连续（形成短的系列，最多10个齿状体），并且不会明显改变龙骨的高度。另外，下颌骨的背侧扩展和弯曲的后部区域使齿列相对于颌关节移位，从而有利于扩大齿列并增加最佳间隙。因此，霸王龙本来应该是一个大型的海洋捕食者，比起其他同时代的or鱼更适合捕食更大的猎物。一项最新的系统发育分析发现，霸王龙是Geosaurini分支的姊妹分类群。孤立的牙齿，肱骨和保存完好的下颌骨表明，第二种子宫甲超掠食者也可能生活在牛津粘土海中。最后，我们修改了其他牛津黏土类杂种的诊断和描述，为区分许多同时期的分类群和这种特殊的化石组合提供了指导。

著录项

  • 来源
    《Journal of Systematic Palaeontology》 |2013年第4期|475-513|共39页
  • 作者

    Mark T. Young; Marco Brandalise de Andrade; Stephen L. Brusatte; Manabu Sakamoto; Jeff Liston;

  • 作者单位

    Institute of Biodiversity, Animal Health and Comparative Medicine,University of Glasgow, University Avenue, Glasgow, G12 8QQ, UK,School of Geosciences,University of Edinburgh, Crew Building, The King's Buildings, West Mains Road, Edinburgh, EH9 3JW, UK;

    Departamento de Paleontologia e Estratigrafia, Instituto de Geociencias, Universidade Federal do Rio Grande do Sul - UFRGS, Av. Bento Goncalves 9500, Porto Alegre (RS), Brazil, 91501-970,CP. 15001;

    Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, U.S.A,Department of Earth and Environmental Sciences, Columbia University, New York, NY, U.S.A;

    Department of Earth Sciences, University of Bristol,Wills Memorial Building, Queen's Road, Bristol,BS8 1RJ, UK;

    School of Life Sciences,University of Glasgow, University Avenue, Glasgow, G12 8QQ, UK;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

    denticle; Geosaurini; hypercarnivore; Metriorhynchidae; Tyrannoneustes;

    机译：迷迭香？土s？食肉动物？适中吗？暴君;

相似文献

  • 外文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号