The "Nioi-tachitsubo-sumire" (Viola obtusa) belongs to Violaceae (the Violet family). It is a perennial herb that is native to Japan, the Korean Peninsula and northeastern China. This herb grows in sunny woodlands, forest edges or grasslands and can reach 5-10 cm in height. The leaves are round ovate. The flowering stalks are borne and the scented magenta flowers bloom from April to May. It is similar to "Tachitsubo-sumire" (Viola grypoceras), though it is defined by dark flower-color and clear striped patterns.