<正>Hainan and Guangdong provinces,located in north tropical area and south subtropical area of China respectively,bear one of the highest levels of biodiversity in China.The modern floras of Hainan and Guangdong are dominated by pantropical and tropical-subtropical taxa and many of their representative families appeared as early as in the Eocene[1].The Eocene,therefore,represents a crucial stage in the formation of the extant flora.However,previously the Eocene floras and vegetation were largely studied in mid-