A new Celastrus species from the middle Miocene of Yunnan, China and its palaeoclimatic and palaeobiogeographic implications

Leaves of a new species ofn Celastrus nL. ( Celastrus caducidentatus nLiang XQ et ZK Zhou) are described from the middle Miocene of Zhenyuan, China. They have serrate theoid teeth with clear, deciduous setae and pinnate venation. The species is closely related ton Celastrus paniculatus nssp.n paniculatus nand probably belongs to subgenusn Celastrus nseriesn Paniculati. According to the nearest living relative approach, its presence suggests that Zhenyuan had a warmer and more humid climate in the middle Miocene and that ancestors ofn C. paniculatus nprobably occurred in East Asia. The distribution history of the genus shows that the North Atlantic corridor and/or Bering continental bridge played an important role in the migration between North America, Europe and Asia. The affinity betweenn C. caducidentatus nandn Celastrus pringlei nRose, which is only distributed in Mexico, suggests that a transpacific dispersal existed between East Asia and Central America.