The plant - Najas marina, is commonly known as spiny water nymph, spiny naiad and holly-leaved naiad.
According to the Dr. Wasantha Welianga of the Rajarata university, it was initially found in Sri Lanka from near the Madu river in 2012.
This spiky plant species has become a nuisance for freshwater fisherman in the area, obstructing boats, damaging fishing nets and spikes stinging the limbs of fishermen.
This has compelled fishermen to manually remove armfuls of these plants from the shallow water areas but to no avail.
According to specialists and fishermen, the only known solution is to introduce the fish species of Grass carp, which is known to eat this plant.
(Pics : Jude Samantha - Puttalam Correspondent)