Azolla (mosquito fern, duckweed fern, fairy moss, water fern) is a genus of seven species of aquatic ferns, the only genus in the family Azollaceae. They are extremely reduced in form and specialized, looking nothing like conventional ferns but more resembling duckweed or some mosses. Ecology Azolla floats on the surface of water by means of numerous, small, closely-overlapping scale-like leaves, with their roots hanging in the water. They form a symbiotic relationship with the cyanobacterium A… (More on Azolla)