Chinese Academy of Geological Sciences, Beijing 100037, China.
State Key Laboratory of Palaeobiology &Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China.
Sci Rep. 2016 Dec 16;6:38191. doi: 10.1038/srep38191.
The fossil record of Ginkgo leaf and reproductive organs has been well dated to the Mid-Jurassic (170 Myr). However, the fossil wood record that can safely be assigned to Ginkgoales has not yet been reported from strata predating the late Early Cretaceous (ca. 100 Myr). Here, we report a new fossil wood from the Mid-Late Jurassic transition deposit (153-165 Myr) of northeastern China. The new fossil wood specimen displays several Ginkgo features, including inflated axial parenchyma and intrusive tracheid tips. Because it is only slightly younger than the oldest recorded Ginkgo reproductive organs (the Yima Formation, 170 Myr), this fossil wood very probably represents the oldest bona fide fossil Ginkgo wood and the missing ancestral form of Ginkgo wood evolution.
银杏叶和生殖器官的化石记录可以追溯到中侏罗世（1.7 亿年前）。然而，在早白垩世晚期（约 1 亿年前）之前的地层中，尚未有可以安全归入银杏类的化石木记录。在这里，我们报告了一个来自中国东北中-晚侏罗世过渡期（153-165 百万年前）的新化石木。新的化石木标本显示出几个银杏特征，包括膨胀的轴向薄壁组织和侵入的管胞尖端。由于它仅比最早记录的银杏生殖器官（1.7 亿年前的义马组）略年轻，因此该化石木很可能代表最古老的真正的银杏化石木，也是银杏木进化缺失的祖先形式。
