Fruits of Ceratophyllum (Ceratophyllaceae) from the late Miocene in Huaning, Southwest China and its paleoecological and paleophytogeographical significances

Abstract Ceratophyllum L. is a genus of submerged aquatic plant with a cosmopolitan distribution. In this study, we first described fruit fossils of C. demersum collected in the Miocene (Xiaolongtang Formation) in Huaning, Yunnan, Southwest China. The materials indicated that a lake with shallow water existed in Huaning in the late Miocene. Based on fossil data, the genus may earliest appeared in the Cretaceous of North America and evolved into sect. Ceratophyllum, sect. Muricatum and sect. Submersum accompanying by the global climate change during the Cenozoic. Its distribution gradually expanded throughout the period. Plants of the genus was present in Southwest China by the late Miocene.