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首次报道我国渐新世银杏属植物叶化石。化石采自黑龙江汤原县太平川剖面宝泉岭组,角质层保存状态良好。叶为下气孔式。上表皮细胞垂周壁平直,平周壁较平。下表皮大量气孔器不规则地散布于脉间区,形成气孔带;气孔密度约为117个/mm2;气孔器为单环式,保卫细胞下陷,侧副卫细胞角质化强烈并形成乳突。当前材料的形态及显微构造特征与古近纪北半球广泛分布的铁线蕨型银杏Ginkgo adiantoides(Ung.)Heer emend.Flo-rin(auctorum multorum)基本一致。这是我国目前已知年代最新的银杏大化石记录,对于探究银杏属在我国新生代的分布、迁徙以及当时相关的古植物地理和气候环境等具有重要意义。
The first report of the Oligocene Ginkgo Phyllostachys fossil in China. The fossils were collected from the Baoquanling Formation in the Taipingchuan section of Tangyuan County, Heilongjiang Province. The stratum corneum was preserved in good condition. Leaves for the next vent. On the epidermal cells vertical wall straight, flat wall flat. A large number of stomata in the lower epidermis irregularly spread in the interventricular zone to form stomatal bands. The stomatal density was about 117 per mm2. Stomatal apparatus was monocyclic and the guard cells were subsided. The keratinocytes on the side were more keratinized and formed papillae. The morphologies and microstructural features of the present materials are consistent with those of the widely distributed Ginkgo adiantoides (Ung.) Heer emend.Flo-rin (auctorum multorum) in the northern hemisphere. This is the latest ginkgo fossil record in our country which is currently known. It is of great significance to explore the distribution and migration of Ginkgo biloba in the Cenozoic of China and the related geology and climatic environment of ancient plants.