• 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 >PRUNUS AND OEMLERIA (ROSACEAE) FLOWERS FROM THE LATE EARLY EOCENE REPUBLIC FLORA OF NORTHEASTERN WASHINGTON STATE, U.S.A.
【24h】

PRUNUS AND OEMLERIA (ROSACEAE) FLOWERS FROM THE LATE EARLY EOCENE REPUBLIC FLORA OF NORTHEASTERN WASHINGTON STATE, U.S.A.

机译：美国东北华盛顿州晚始新世共和国植物区系中的李子和小枝菌（蔷薇科）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

Two genera of Rosaceae are described from the latest early Eocene Republic flora of northeastern Washington State, United States. Prunus cathybrownae sp. nov. (Rosaceae: subfamily Spiraeoideae, tribe Amygdaleae sensu Potter et al.) is based on eight flowers, including one containing in situ pollen and two immature fruits. Flowers are actinomorphic, perigynous, and pentamerous, with a campanulate hypanthium bearing five sepals. The gynoecium is unicarpellate and consists of a distally flared, bilobed stigma; an elongate style; and an ellipsoid, bilaterally asymmetric ovary. Two whorls of stamens—an inner one in which stamens are reflexed and an outer whorl of extended stamens—are both inserted into the hypanthium. Pollen from the outer whorl is 20 /xm in diameter and tricolporate with a striately ornamented exine; clusters of smaller, presumably immature grains 7 /xm long and 4 /am wide lacking distinctive ornamentation were recovered from the inner whorl. Immature fruits differ from the flowers in either having a senescent style or lacking one entirely and having fewer remnants of perianth parts and a larger and more symmetrical ovary. A second flower, Oentleria janhartfordae sp. nov. (Rosaceae: subfamily Spiraeoideae, tribe Osmaronieae sensu Potter et al.) is actinomorphic and perigynous and has five free pistils that each resemble the solitary pistil of Prunus. These include a flattened, bilobed stigma and an ellipsoid, bilaterally asymmetric ovary. The fossil has the laterally fixed, elongate style characteristic of the genus. These fossils are the oldest known floral examples of these two genera and demonstrate that both Prunus and Oemleria were present in the latest early Eocene in western North America. The Okanogan Highlands floristic province provides the earliest fossil evidence to date for the first major radiation of the Rosaceae, an important mostly temperate, mostly Northern Hemisphere family.
机译：从美国华盛顿州东北部最新的始新世早期植物区系中描述了蔷薇科的两个属。李属Cathybrownae sp。十一月（蔷薇科：螺旋藻亚科，扁桃体（Amygdaleae sensu Potter）等）以八种花为基础，其中包括一朵原位花粉和两朵未成熟的果实。花是放射状的，近生的和五花状的，钟状的玻璃托有五个萼片。妇产科是单生的，由一个向远端张开的双叶柱头组成。细长的样式；和一个椭圆形，两侧不对称的卵巢。两个雄蕊轮-一个内部的雄蕊被反射和一个外部的延长雄蕊轮-都插入了玻璃瓶。外轮花粉的直径为20 / xm，三孔孢子，外缘有细纹。从内轮中回收了一些簇，这些簇簇较小，大概是未成熟的7 / xm长和4 / am宽的谷物，没有明显的装饰。不成熟的果实与花的不同之处在于，其具有衰老的样式或完全缺乏花朵，并且花被残片较少，而子房较大且对称。第二朵花，Oentleria janhartfordae sp。十一月（蔷薇科：绣线亚科，Osmaronieae sensu Potter等人的部落）是放射状的和具雌性的，有五个游离的雌蕊，每个类似于雌蕊的雌蕊。这些包括扁平的双叶柱头和一个椭圆形，两侧不对称的子房。化石具有属的横向固定，细长的特征。这些化石是这两个属中最古老的已知花卉实例，表明在北美西部最新的始新世中都存在李属和Oemleria。冈那根高地植物区系提供了迄今为止最早的蔷薇科植物主要辐射的化石证据，蔷薇科植物是重要的温带植物，主要​​是北半球。

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