Fruits And Seeds From Yunnan In The Age Of Miocene And From Shanxi In The Age Of Pliocene

Palaeocarpological studies on Tertiary fruits and seeds have achieved in Europe and North America. However, Tertiary fruits and seeds in China were found rarely and not studied in detail so far. In this paper, we investigated the fruits and seeds in detail from Yunnan in the age of Miocene and from Shanxi in the age of Pliocene.1. A Miocene flora of fruits and seeds is reported from a brown coal mine, named as Mangdan, in western Yunnan, SW China. This flora contains 29 species of angiosperm and the fruits and seeds of 14 species in the flora were studied in details. The 14 species belong to 11 families and 12 genera, ie. Lithocarpus (Fagaceae), Corylopsis (Hamamelidiaceae), Hypericum (Hypericaceae), Litsea (Lauraceae), Magnolia (Magnoliaceae), Liriodendron (Magnoliaceae), Ficus (Moraceae), Myrica (Myricaceae), Nyssa (Nyssaceae), Zanthoxylum (Rutaceae), Sabia (Sabiaceae) and Symplocos (Symplocaceae). All these fossil fruits and seeds are reported for the first time in China, and Corylopsis, Liriodendron, Nyssa, Sabia and Symplocos are new additions to the Chinese megafossil plants. The modem equivalents of the 14 species suggest that a subtropical evergreen broad-leaved forest was growing in the area surrounding Mangdan during Miocene, under warm and humid subtropical climate.2. Numerous specimens of fruit and seed of Ruppia were, for the first time, found from the Zhangcun Formation in the age of Late Pliocene (2.3-3.5 millions years old)in Yushe Basin, Shanxi, North China. These specimens of Ruppia are characterized by possessing a small oval endocarp, smooth endocarp surface, distinct narrowly elliptic external depressions, distinct apical mucro, slightly curved seed shape and conspicuous globose hilum. A new species, R. yushensis sp. nov. is established for these specimens of the endocarp and seed. Comparison with two species of Ruppia in the age of Miocene from Europe indicates the existence of three fossil species from Miocene to Pliocene and from Europe to East Asia stratigraphically and geographically. R. yushensis is an aquatic plant in the lake of Zhangcun at that time and indicates a brackish, clear, tranquil and shallow lake in this region in Late Pliocene. The smooth endocarp surface further suggests a warm temperate or temperate palaeoclimate.