Blue Lotus (Nymphaea nouchali var. caerulea [Syn: Nymphaea capensis])

An introduced aquatic herb with floating leaves, native to the Africa. Cultivated and also escaped and naturalized in ponds and tanks. Flowering throughout the year. Often confused with the national flower of Sri Lanka - Nymphaea nouchali

ඕලු[Olu]/Water Lilly (Nymphaea pubescens)

Olu is a very common indigenous aquatic herb of ponds and tanks, particularly in the dry lowlands. Flowering throughout the year and color of the flowers vary from nearly white to red. The seeds are edible and also use in traditional medicine. 

නිල් මානෙල්[Nil Manel]/Common water Lilly(Nymphaea nouchali)

An indigenous aquatic herb with floating leaves common in ponds and tanks of lowlands, particularly in dry zone and often cultivated in other areas. Flowering all the year round and flowers used for worshipping in Buddhist temples.