Vegetative key to the families
Vegetative Key Vegetative key to the families
FREE FLOATING WATER PLANTS; roots, when present, not rooted in the mud. (Note: there are 2 genera of ferns which are free floating, see Azolla and Salvinia)
Whole plant not exceeding 5 mm long Lemnaceae
Roots absent Wolffia
Cladode widest just below the water surface, globular to ovoid, less than twice as deep as wide, up to 0.7 mm long, green at the edge and paler in the centre, usually with less than 25 stomata on the upper surface, flat near the apex, acute at the edges. Widespread. Still water Wolffia globosa
Cladode widest at the water surface, at least twice as deep as wide