One dispersal event in clade I occurred in the early Pliocene from southern East Asia to Japan (ca. 4.85 Ma, 95% HPD: 2.98–6.80; node 4). The most recent common ancestor of Japanese Pseudotsuga japonica (Shiras) Beissn. and mainland Chinese P. gaussenii Flous and P. sinensis Dode (Pinaceae) was estimated to occur at ca. 4.64 ± 1.93 Ma . In Eupteleaceae, Chinese Euptelea pleiosperma Hook. f. & Thomson split with Japanese E. polyandra Siebold & Zucc. at ca. 6.04 Ma (95% HPD: 2.89–9.36) . The drop of sea level may have resulted in exchanges of plants between mainland Asia and the Japanese Islands via the East China Sea land bridge, and subsequent rise of sea level and global cooling (Fig. 2) , as well as an increasingly drier climate in Asia , may have caused the interruption of the continuous distribution of ancestral populations of some extant species during the Late Miocene to the Early Pliocene.