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The genus Paliurus is characterized by its distinctive orbicular-winged fruits and a trilocular(or bilocular) ovary. Macrofossil records suggested this genus was distributed widely in North America, Europe, and Asia during the Paleogene and Neogene, before its present limitation to Eurasia. In this study, we describe some Paliurus fossil winged fruits from the lower part of Youganwo Formation(middle Eocene) and Huangniuling Formation(late Eocene) of the Maoming Basin, South China. These fruits are recognized as Paliurus favonii Unger based on a detailed study on the fossil morphology and cuticle characteristics. This represents the earliest occurrence of Paliurus fossil fruits in eastern Asia, and to date is the world’s lowest latitude appearance for this genus. The most ancient records of Paliurus throughout the world are from the middle Eocene of North America and the late Eocene of Japan, leading some researchers to conclude the Paliurus may have originated in North America. Molecular data, however, do not support this hypothesis. The present Paliurus fossil fruits provide new evidence for the origin and phytogeographic history of this genus.
The genus Paliurus is characterized by its distinctive orbicular-winged fruits and a trilocular (or bilocular) ovary. Macrofossil records suggest this genus was distributed widely in North America, Europe, and Asia during the Paleogene and Neogene, before its present limitation to Eurasia. In this study, we describe some Paliurus fossil winged fruits from the lower part of Youganwo Formation (middle Eocene) and Huangniuling Formation (late Eocene) of the Maoming Basin, South China. These fruits are recognized as Paliurus favonii Unger based on a detailed study on the fossil morphology and cuticle characteristics. This represents the earliest occurrence of Paliurus fossil fruits in eastern Asia, and to date is the world’s lowest latitude appearance for this genus. The most ancient records of Paliurus throughout the world are from the middle middle Eocene of North America and the late Eocene of Japan, leading some researchers to conclude the Paliurus may have originated in North America. Molecul ar data, however, do not support this hypothesis. The present Paliurus fossil fruits provide new evidence for the origin and phytogeographic history of this genus.