...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>International journal of plant sciences >CATANTHUS, AN EXTINCT MAGNOLIID FLOWER FROM THE EARLY CRETACEOUS OF PORTUGAL
【24h】

CATANTHUS, AN EXTINCT MAGNOLIID FLOWER FROM THE EARLY CRETACEOUS OF PORTUGAL

机译：catanthus，来自葡萄牙早期的白垩纪的灭绝的木兰花

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

Premise of research. Early Cretaceous flowers recovered from Portugal and North America are some of the oldest and most informative angiosperm structures known. Analyses of this material provide a more direct basis for inferring floral structure and biology in early angiosperms than extrapolations based solely on extant taxa, and they have documented an unanticipated diversity of angiosperms, including the presence of many extinct forms, during the Early Cretaceous. The fossil flower described here from the Early Cretaceous of Portugal adds to the knowledge of this extinct diversity. Methodology. Coalified fossil flowers were extracted from unconsolidated sediments and cleaned with HF, HCl, and water. Details were studied using scanning electron microscopy and synchrotron radiation X-ray to-mographic microscopy. Phylogenetic relationships were evaluated by adding the fossil to a phylogenetic analysis of extant basal angiosperms based on morphological characters but constrained according to a topology based on molecular data. Pivotal results. A new genus and species, Catanthus dolichostemon, are described on the basis of the fossil flowers. The perianth consists of three thick sepal-like tepals in an outer whorl and six thinner petallike tepals in two inner whorls. The androecium consists of several whorls of stamens with long, broad filaments and anthers with extrorse dehiscence. Pollen is trichotomocolpate and possibly monocolpate. The gynoecium is superior and apocarpous, consisting of six or, rarely, five carpels. Analysis of the phylogenetic position of Catanthus suggests a relationship to Canellales and Magnoliales. Conclusions. Catanthus is a new Early Cretaceous magnoliid angiosperm for which the relationship to the two major clades of extant magnoliids (Laurales + Magnoliales or Canellales + Piperales) is not resolved securely. Catanthus adds to the evidence of substantial extinct diversity among early angiosperms, including the presence of extinct forms related to extant magnoliids, and it is consistent with a general pattern that angiosperm assemblages from the middle Albian and earlier are dominated by noneudicots.
机译：研究的前提。从葡萄牙和北美中恢复的早期白垩纪花是已知的最古老，最富有的高级植物植物结构。该材料的分析为早期高血管植物中的推断性和生物学提供了更直接的基础，而不是仅基于现存的分类群，他们已经记录了一个意想不到的血糖植物，包括在早期白垩纪期间存在许多灭绝形式的存在。来自葡萄牙早期的白垩纪中描述的化石花增加了这种灭绝多样性的知识。方法。从未溶解的沉积物中提取联合化石花，用HF，HCl和水清洗。使用扫描电子显微镜和同步辐射X射线到Mographic显微镜研究了细节。通过基于形态学特征将化石添加到远端基础高血管培养物的系统发育分析，而是根据分子数据的拓扑结构来评估系统发育关系。关键结果。在化石花的基础上描述了新的新属和物种，Catanthus dolichostemon。 Perianth在外螺纹中的三个厚的萼片样细胞膜组成，两个内螺纹中的六个较薄的丝绒。 AndroeCium由几轮雄蕊组成，具有长，宽阔的长丝和花药，具有开放的裂缝。花粉是三分球蛋白，可能是单一的。吉诺纤维是优越的，并且是一个六个或很少，五个心皮。分析毛花纹的系统发育位置表明与牛肉和木龙的关系。结论。 catanthus是一种新的早期白垩纪玉米醛植物，其与突出的木兰（Laurales + magnoliales或Canlellales +派热物）的关系牢固地进行了安全。 catanthus增加了早期高昂的灭绝多样性的证据，包括存在与现存的木兰有关的灭绝形式，并且它与中间白葡萄球菌和早期的有原植物组合的一般模式一致地由非统计算出来。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
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