Salvina natans, is often mistaken as some kind of floating aquatic moss but actually this is a floating aquatic fern. Salvina natans has small, round leaves covered with tiny water proof hairs called papillae. Each node of the plant has a pair of floating leaves and as well as a third submerged leaf that serves as root. The spore is stored at the base of the submerged leaf. Salvina natans is found in almost every corner of the world. It is a quite common plant species found in Central Europe, South America, Asia as well as Africa. Few reasearchers say that Salvina is actually originated from South America, Maylasia, or Central Europe. This is a quite aggressive and fast growing plant and has a reputation as invasive weed.
Salvina is a very common aquarium plant and popular among the aquarists. This is a nice ornamental addition to all open top tanks, but it needs to be monitored and trimmed regularly. This is also great for breeding set ups. Its submerged leaves and roots provide nice hiding places for the fries.