Japanese name: コナギ（小菜葱） Scientific name:Monochoria vaginalis var. vaginata
[Overview]
An annual 20–30 cm tall, found in rice paddies, shallow ponds and marshes, and wetlands.
The stem is short, and each bears one leaf.
The leaves are 3–7 cm long and vary in shape, such as lanceolate or ovate-heart-shaped.
The leaf surface is glossy.
The leaf stalk is long and sheathing at the base.
A raceme emerges from the leaf axil.
The inflorescence is shorter than the leaves.
The flowers are 15–20 mm across, blue-violet and six-petaled.
Each flower withers in a day.
After flowering, the base of the inflorescence bends downward so that the seeds drop into the water.
The fruit is a capsule.
[History]
It is thought to be a prehistoric naturalized plant that arrived along with the spread of paddy rice.
It is also mentioned in poems in the Man'yoshu.
