Nymphoides coreana is
a perennial herb found in ponds, marshes, or paddies, emerging long,
slender 'stems' from rhizomes in a petiole way. Blades position on
the tips of them. Leaves (the edges) are concentric or
concentric-ovate, 2-6cm in length, 2-4cm in width, and many have
purplish-brown mottled patterns on their surfaces. There are nodes
on the 'stems' at somewhat upper parts from the midpoints, from
which flower buds or new vegetative growths (leaves with 'stems,'
the same thing mentioned above) start—the latest developments root
in due course. Flowers, white, 4- or 5-petaled, 8mm in diameter,
have thick white hairs on the margins and a few insides. Fruit is
oblong and has many seeds inside, germinating approximately in May.
As for the 'stem,' a lower portion from the node may be a genuine
stem, and the upper a petiole. Be that as it may, the 'stems' exist
with no nodes also. How can it be explained? Who knows at the
moment? Bloom time: July-October.