The Earliest Normal Flower from Liaoning Province, China  

作　　者：Xin Wang Shaolin Zheng 

机构地区：[1]Nanjing Institute of Geology and Palaeontology, the Chinese Academy of Sciences, Nanjing 210008, China [2]Fairylake Botanical Garden, Shenzhen 518004, China [3]Shenyang Institute of Geology and Mineral Resources, Shenyang 110032, China

出　　处：《Journal of Integrative Plant Biology》2009年第8期800-811,共12页植物学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China (40772006,40372008, 40632010 and J0630967); Resources Platform of Mineral Rockand Fossil, and the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry

摘　　要：The early evolution of angiosperms has been a focus of intensive research for more than a century. The Yixian Formation in western Liaoning yields one of the earliest angiosperm macrofioras. Despite multitudes of angiosperm fossils uncovered, including Archaefructus and Sinocarpus, no bona fide normal flower has been dated to 125 Ma （mega-annum） or older. Here we report Callianthus dilae gen. et sp. nov. from the Yixian Formation （Early Cretaceous） in western Liaoning, China as the earliest normal flower known to date. The flower demonstrates a typical floral organization, including tepals, androecium, and gynoecium. The tepals are spatulate with parallel veins. The stamens have a slender filament, a globular anther, bristles at the anther apex, and in situ round-triangular pollen grains. The gynoecium is composed of two stylate carpels enclosed in a fleshy envelope, and develops into a ＂hip＂ when mature. Since the well-accepted history of angiosperms is not much longer than 125 Ma, Callianthus together with Chaoyangia, Archaefructus and Sinocarpus from the Yixian Formation demonstrate a surprisingly high diversity of angiosperms, implying a history of angiosperms much longer than currently accepted.The early evolution of angiosperms has been a focus of intensive research for more than a century. The Yixian Formation in western Liaoning yields one of the earliest angiosperm macrofioras. Despite multitudes of angiosperm fossils uncovered, including Archaefructus and Sinocarpus, no bona fide normal flower has been dated to 125 Ma （mega-annum） or older. Here we report Callianthus dilae gen. et sp. nov. from the Yixian Formation （Early Cretaceous） in western Liaoning, China as the earliest normal flower known to date. The flower demonstrates a typical floral organization, including tepals, androecium, and gynoecium. The tepals are spatulate with parallel veins. The stamens have a slender filament, a globular anther, bristles at the anther apex, and in situ round-triangular pollen grains. The gynoecium is composed of two stylate carpels enclosed in a fleshy envelope, and develops into a ＂hip＂ when mature. Since the well-accepted history of angiosperms is not much longer than 125 Ma, Callianthus together with Chaoyangia, Archaefructus and Sinocarpus from the Yixian Formation demonstrate a surprisingly high diversity of angiosperms, implying a history of angiosperms much longer than currently accepted.

关 键 词：ANGIOSPERM bisexual Callianthus Early Cretaceous FLOWER LIAONING PERIANTH Yixian Formation 

分 类 号：Q914.2[天文地球—古生物学与地层学] Q915.864[生物学—古生物学]