Sagittaria pygmaea
Sagittaria pygmaea, commonly known as the dwarf arrowhead or pygmy arrowhead, is an aquatic plant species. It is a perennial herb producing by means of stolons. Leaves are linear to slightly spatula-shaped, not lobed, up to long.
It is native to Japan, Korea, Taiwan, Thailand, Vietnam, Bhutan and China. It grows in shallow water in marshes, channels and rice paddies.