The Salviniaceaefamilyincludes twogenera –the Azolla Lam.genus and theSalvinia Séggenus. The members of thefamilyare aquatic fern-like plants. They originate from the tropical parts of South America.
A typical member of the family is theSalvinia natans (L.) All., a species of fern-like plant of the Salviniaceaefamily. It is a small floating plant with thin horizontal stem and leaves arranged in nodes in threes. The two superior leaves are elliptic, while the lower ones are submerged – modified in root-like filaments.
It is spread all over the world in areas with stagnant freshwater basins, sunlight, and humid air growing most often in Africa, Asia, Central Europe and South America. InBulgaria,it can be found in the bogs and slow running waters by the Danube river, the Black Sea, the valley of Maritsa river and other places.