First record of extinct fruit genus Chaneya in low-latitude tropic of South China.

Fossil reproductive structure from the Eocene of the Changchang Basin (Hainan Island, South China) is recognized as Chaneya hainanensis sp. nov. This new species is characterized by persistent corolla of five obovate petals with three subparallel primary venation linked by arching secondary veins, circular central disk bearing two orbicular ovaries or fruit bodies. This discovery confirms the presence of the extinct fruit genus Chaneya in low-latitude tropical area, providing significant fossil evidence for investigating the origin, migration, and phytogeography of this genus and discussing the Tertiary floristic exchanges among North America, eastern Asia, and Europe. Considering the distribution of this genus and its extant relatives and the climate changes during the Cenozoic, we hypothesize that Chaneya was a widespread tropical or subtropical taxon, but, with climate cooling, became extinct in northern latitudes and evolved into Picrasma (Simaroubaceae) and Rutaceae mainly in modern tropics and subtropics. [ABSTRACT FROM AUTHOR]