An aquatic herb that is naturalised in Australia and considered a weed in some areas.
Plants grow up to 50 cm high with stolons up to 45 cm long.
The stolon is a long horizontal stem with nodes from which roots, leaves and flowers grow.
In the Water Poppy they float on the surface and new plantlets also arise from the nodes.
Leaves are on short or long petioles with bases that sheath the stem.
They are a shiny, dark green and float on the water or are sometimes above it.
The blade is round to ovate, up to 12 cm long and has up to 9 veins.
The leaf base is heart-shaped (cordate).
Inflorescences of up to 6 flowers are on stalks up to 30 cm long.
Bracts are present.
Each 6.5 cm wide flower, held above the water, only lasts one day.
There are 3 sepals and 3 spreading petals.
Petals are pale yellow or white with a yellow base.
There are 20 to 25 black or brown stamens and about the same number of staminodes.
There are 5 to 8 carpels.
Fruit are up to 15 mm long and the tiny 1mm seeds have a few hairs.