Fossil leaves, fruits and pollen of Liquidambar (Hamamelidaceae) from the Lower Miocene Nakamura Formation in Gifu Prefecture, central Japan

Abstract

The genus Liquidambar (Hamamelidaceae) is one of a number of taxa associated with the Daijima-type floras of late Early to early Middle Miocene age, which also include many warm-temperate to subtropical elements. However, Liquidambar is very rare or absent in the Aniai-type floras of the early Early Miocene. We describe fossil leaves, fruits and pollen of this genus found in the Lower Miocene Nakamura Formation in the southern part of Gifu Prefecture. The flora of the Nakamura Formation (Hiyoshi flora) shows features common to those of the conformably underlying Hachiya Formation (earliest Early Miocene) but differs from the unconformably overlying Hiramaki Formation (late Early Miocene) in the same region. This fact combined with the occurrence of Liquidambar in the Hiyoshi flora, associated with warm-temperate elements such as Pseudolarix, Castanea, Celtis and Lindera, clearly supports one of two former views: the flora is of a southern type within the Aniai-type floras.