First Oligocene mummified plant Lagerstätte at the low latitudes of East Asia

Mummified fossils are extraordinarily important for understanding both biotic evolution and ecology in the geological time, by uniquely providing a far more detailed source of information in comparison to impression materials. However, mummified fossils are extremely rare because of the inevitable requirement of unusual preservation conditions during fossilization, including the lithological features and deposition rate of surrounding rocks, and moisture and temperature conditions (Taylor et al., 2009). To date, only a few Cenozoic sites have been reported to yield mummified plant fossils around the world, such as the middle Miocene forest (Williams et al., 2008) and the Eocene fossil forest (Liu and Basinger, 2009) both from the Canadian High Arctic and the leaves from the Eocene of Anglesea, Australia (Christophel et al., 1987). Here we report on an exceptional plant fossil Konservat Lagersttte from the Nanning Basin of Guangxi, southern China (225250N, 108252E; Figure 1(a)), documenting the Oligocene mummified fossil flora in the low-latitude region of East Asia for the first time (Figures 1(b)(f) and 2(a)(q)). So far, more than 500 stumps, 1000 fruits and seeds, and copious leaves have been collected from this Lagersttte.