The Salviniaceae are a family of ferns, which contains the single genus Salvinia. Salvinia is a floating fern, and the Salviniaceae are related to the other water ferns, including the Mosquito fern, Azolla. Some sources include Azolla in Salviniaceae, although the genus is generally given its own family, Azollaceae. Salviniaceae and the other fern families in Order Marsileales are heterosporous, producing spores of differing sizes.