Late Miocene Pods and Leaves of Albizzia (Leguminosae: Mimosoideae) from Yunnan, SW China and Their Phytogeographic Implications

Albizzia is a leguminous genus belonging to the subfamily Mimosoideae with approximately 150 modern species, widely distributed in the tropical and subtropical regions of Asia, Africa, Australia and America. Among them, 17 species are mainly distributed in southern and southwestern China. Abundant fossils of the subfamily Mimosoideae, including leaves, pods, flowers and wood, have been reported from the Cretaceous and Paleogene strata of the Northern Hemisphere. However, Neogene records of Mimosoideae are relatively scarce. In this study, fossil pods and leaves belonging to the genus Albizzia from the Bangmai Formation of Yunnan, China were described. They were assigned to three species, including Albizzia scalpelliformis Guo, Li and Xie Emended, Albizzia cf. kalkora (Roxb.) Prain and Albizzia sp. The occurrence of Albizzia fossils from Lincang not only gives important information on the Neogene plant diversity from Yunnan a worldwide famous biological hotspot but also provides additional evidence for its phytogeographic history.