American waterfern, Pacific mosquitofern
There are six species of Azolla in the world. American waterfern is the species commonly found in Florida. American waterfern is a small, free-floating fern, about one-half inch in size. It is most often found in still or sluggish waters. Young plants are, at first, a bright or grey-green. Azolla plants often turn red in color. American waterfern can quickly form large, floating mats.
Azolla leaves are tiny, lacy-looking, and closely overlapping. The leaves can be green or rusty red. American waterfern is a small, floating plant with green or rusty-red leaves. Its leaves are tiny and overlapping.