A new Choerospondias (Anacardiaceae) endocarp from the middle Miocene of Southeast China and its paleoecological implications

Abstract Choerospondias (Anacardiaceae) is a monospecific genus that is mainly distributed in the subtropics and tropics of eastern Asia today. Fossil records suggest that the genus was widely distributed throughout Eurasia during the Oligocene and Miocene. In this paper, we describe a new species of Choerospondias based on three-dimensionally preserved endocarps from the middle Miocene of Fujian, Southeast China. The internal structures and anatomical details of the fossils were studied using Micro-CT and physical sections. Choerospondias fujianensis sp. nov. is characterized by having five or seven radially arranged germination pores at the subapical region of endocarp. Fossils indicate that Choerospondias was more diverse in the Miocene than today. The genus has a nearly continuous fossil record in East Asia since the Oligocene. Fossil evidence also indicates that Choerospondias was a minor component in several different types of evergreen forests along river channels in subtropical to probably tropical climates since its early history. The relatively wide range of adaption of Choerospondias may play an essential role in its current survival in East Asia.