Hottonia palustris (Water violet) is a pinnate-leafed aquatic plant native to wetland areas throughout Europe, where it is threatened, endangered, or extinct in certain parts of its range. It is usually found growing totally submersed except for the long flower spikes each bearing a set of light purple flowers.
This non-tropical plant requires cooler water (below 76 deg f), strong lighting and a steady supply of nitrates and phosphates through the water column. Shading will induce melting so lighting consistently is tremendously beneficial. CO2 will further promote healthy growth but is not compulsory for tank raising.
This species is rarely if ever found at retail and often acquired through the hobbyist trade.