Slight resemblance to : Water Lobelia (Lobelia dortmanna) which also grows in shallow fresh water with similar colour flowers and the same number (five) of petals, but which grows mainly north of Lancaster rather than south) and belongs to the Bellflower Family (Campanulaceae),

Superficial resemblance to : Narrow-leaved Water-plantain (Alisma lanceolata) and to Flowering-Rush (Butomus umbellatus), aquatic plants which have similar coloured flowers but only three petals.

Uniquely identifiable characteristics

Distinguishing Feature :

No relation to : Violets such as Common Dog Violet (Viola riviniana) [plants with similar names but are in a differing family, the  Violet Family Violaceae].

Grows in shallow fresh-water often in-accessible to close photography. Most aquatic plants have but three petals, not so Water Violet with five. Distrubution mainly south of Lancaster. The only plant in the Hottonia Genus (at least in the UK). All leaves are submerged, pinnate and in whorls.