Vallisneria natans

Under the name Vallisneria natans, smooth-leaved vallisnerias are known in the aquarium hobby, but true V. natans may not be in cultivation.

The species Vallisneria natans was originally described as Physkium natans; the original description gives Indochina as its origin. In his 1982 revision of the genus Vallisneria, Lowden states that the name is probably a synonym of V. spiralis var. denseserrulata. In the "Flora of China", on the other hand, Vallisneria natans is treated as a species that includes Vallisneria asiatica. In their molecular systematic study, Les & others (2008) distinguish V. natans and V. asiatica as separate species. With their DNA analyses they also examined various cultivated origins of Vallisneria. Among these, however, the authors were unable to demonstrate the species V. natans. They identified an aquarium plant called "Vallisneria natans" as Vallisneria spiralis.

It is therefore not documented that true Vallisneria natans is cultivated as an aquarium plant. Consequently, no information on the cultivation requirements of V. natans can be given here. But presumably this species could be kept in aquariums just as easily as many other vallisnerias.

Vallisneria natans is apparently a very variable species, as leaf lengths of 20 to 200 cm and widths of 0.5 to 2 cm are given. The leaf tip is blunt, and the leaf margin is entire or inconspicuously toothed. On both sides of the leaf midrib there are two to four longitudinal veins.