A reconstruction of the Fossil Salvinia from the Eocene of Hainan Island, South China

•Salvinia hainanensis sp. nov. from the Eocene of South China is described.•It is the first fertile fossil record of Salvinia from China.•Vegetative leaves and attached fertile structure including microspores are preserved.

Salvinia hainanensis Jin et Wang, sp. nov. is described from the Eocene of Changchang Basin, Hainan Island, South China. The new species is characterized by its keel-like petiole, equilateral areolae with one tubercle in each, and free marginal veins in the float leaves, and, strongly branched submerged leaves, and irregular epidermal cells. The microsporangium is 220–260 μm in diameter, containing 32 microspores. The microspore is trilete, approximately 17–50 μm in diameter. This species represents a most ancient group of this genus, and has little affinity to extant species. Well preserved whole plants and the reproductive organs in situ indicate it grew close to where it was preserved, and associated fossil aquatic plants and sediments corroborate that this was an aquatic environment in the Eocene of the Changchang Basin.