Description from Flora of China
Herbs perennial, rhizomatous. Stems erect or ascending, 30-60 cm, slightly scabrid at base, ± puberulent, angles and nodes villous, branches few or none. Petiole 0-2 mm; leaf blade oblong-lanceolate, 3-7 × 1-2 cm, adaxially sparsely puberulent, villous, abaxially densely white villous-tomentose, villous on veins, base shallowly cordate, margin crenate-serrate, apex acute. Verticillasters 6-flowered, lower widely spaced, upper in terminal spikes 5-8 cm; floral leaves sessile, lanceolate, longer than calyx, margin subentire; bracteoles linear-setiform, ca. 1 mm, puberulent. Calyx campanulate to obconical-campanulate, ca. 7 mm, 10-veined, glandular villous-tomentose, veins sparsely villous, accessory veins inconspicuous; teeth triangular-lanceolate, ca. 2.5 mm, subequal or lower 2 longer, apex spinescent. Corolla reddish or reddish purple, ca. 1.3 cm, sparsely puberulent; limb densely pilose; tube ca. 7 mm, throat puberulent, annulus inconspicuous or absent; upper lip oblong; lower lip spreading, middle lobe reniform, lateral lobes ovate. Filaments puberulent. Nutlets brown, ovoid, ca. 1 mm in diam., glabrous.
Bamboo forests, thickets, dry sandy areas, reed marshes, wet areas; 200-1900 m. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Sichuan, Taiwan, Yunnan [India].