Salviniaceae (/sælˌvɪniˈeɪsiˌiː/),[1][2] is a family of heterosporous ferns in the order Salviniales.
[3] The Salviniaceae contain the two genera Azolla and Salvinia,[4] with about 20 known species in total.
[5] The oldest records of the family date to the Late Cretaceous.
[6] Azolla was previously placed in its own family, Azollaceae, but research has shown Azolla and Salvinia to be sister genera with the likely phylogenic relationship shown in the following diagram.
[7] Marsilea Pilularia Regnellidium Azolla Salvinia