文摘
A leaf of Alseodaphne cf. hainanensis Merrill was discovered in diatomitic sediments of middle Pliocene age at Shengzhou, Zhejiang Province, China. The fossil and modern leaves have the same elliptic shape and brochidodromous venation. The cuticle of the fossil leaf was intact. There are some anatomical differences such as the amount of wax, the position of subsidiary cells and the density of trichomes/trichome bases between the fossil and modern leaves. However, these characters could not be used as taxonomic criteria to distinguish the fossil leaf from the modern species. The restricted distribution of A. hainanensis suggests that this tree is stenoecious. The presence of A. cf. hainanensis indicates that the mid-Pliocene climate was much warmer than today and had a higher level of precipitation than eastern China at the present day. Based on the fossil records and the modern distribution it is suggested that the trees of A. hainanensis have retreated southwards since the middle Pliocene.