"Sasaba-mo" (Potamogeton malaianus) belongs to Potamogetonaceae (the Pondweed family). It is a perennial herb that is native all over Japan, as well as the Korean Peninsula, China, Taiwan and New Guinea. This herb is a submerged plant that grows gregariously in ponds, rivers and ditches. The leaves are oblong to narrow lanceolate and serrate with petioles. The inconspicuous flowers bloom in spikes from July to September.