Description from Flora of China
Herbs erect. Stems 60-100 cm, finely striate, puberulent. Petiole narrowly winged, 1.5-4.5 cm, puberulent; leaf blade triangular-cordate, 4-7.5 × ca. 3.6 cm, thin papery, puberulent, base truncate to cordate, margin dentate-crenate, apex caudate-acuminate. Cymes 7-9-flowered, short pedunculate, in compact, terminal panicles on apices of stems and branches; floral leaves and bracts linear; bracteoles linear, 1-1.5 mm. Pedicel ca. 1 mm. Calyx tubular, ca. 5 mm, densely minute hispid, glandular, throat oblique; teeth lanceolate, ca. 1.7 mm, apex acute. Corolla purple, to 2 cm; tube ca. 0.6 mm in diam. at base, to 6 mm at mouth, puberulent; upper lip ca. 3 × 5 mm, minutely hispid near margin; middle lobe of lower lip inversely cordate, ca. 5 × 6 mm, base cordate, margin undulate, apex rounded; lateral lobes very distinct, subtruncate. Nutlets dark brown, ovoid, triquetrous, ca. 1.5 × 1 mm. Fl. May, fr. Aug.
* Thickets; low elevations. Anhui, Hubei, Zhejiang.