1. Small free-floating aquatic fern from the eastern United States to tropical America; naturalized in western and southern Europe
   "floating fern formed a purple carpet on the pond's surface";
   - mosquito fern, Carolina pond fern, Azolla caroliniana
    
2. Pantropical aquatic fern
   "Floating ferns create a green carpet on the pond's surface";
   - Ceratopteris thalictroides
    
3. Aquatic fern of tropical America often used in aquariums
   "Floating ferns provided cover for the aquarium fish";
   - water sprite, Ceratopteris pteridioides

Derived forms: floating ferns

Type of: aquatic fern, water fern

Part of: Azolla, Ceratopteris, genus Azolla, genus Ceratopteris

Encyclopedia: Floating fern