Description from
Flora of China
Viola diamantiaca f. glabrior (Kitagawa) Kitagawa; V. diamantiaca var. glabrior Kitagawa.
Herbs perennial, acaulescent, with long, slender stolons. Rhizome obliquely ascending or horizontal, slightly robust, densely noded, with numerous long, slender, brown roots. Basal leaves 1, rarely 2 or 3, produced from top of rhizome; stipules free, greenish, lanceolate or narrowly ovate-lanceolate, ca. 1 cm, submembranous when dry, margin remotely denticulate, apex acuminate; petiole to 20 cm, slender, winged, usually puberulous in upper part, glabrous in lower part; leaf blade abaxially glaucous-green, adaxially green, cordate or ovate-cordate, 7-9 × 5-7 cm, thin, adaxially glabrous, puberulous along veins, base shallowly or deeply cordate, margin obtusely dentate, apex caudate-acuminate. Flowers purplish violet or glaucous, large, long pedicellate; pedicels solitary, slender, 2-bracteolate slightly above middle; bracteoles lanceolate, small. Sepals ovate-lanceolate, glabrous, basal auricles short. Lateral petals 1.5-1.7 cm, glabrous, anterior one 1.8-2 cm (spur included); spur short, ca. 4 mm, stout, apex obtuse. Capsule purple-red punctate, ca. 1.3 cm. Fl. Apr-May, fr. Jun-Aug.
Broad-leaved forests on mountains, forest margins, moist rocks; 600-1500 m. E Jilin, E Liaoning [Korea].