形态特征：Herb perennial, rhizomatous. Stems erect, unbranched, 30‒80 cm tall, 2‒3.5 mm in diam., obtusely 4-angled, shallowly canaliculate, densely retrorsely white-setulose. Leaves opposite; blades elliptic, oblong-ovate, elliptic-ovate or ovate, 7‒19 cm long, 3‒9.5 cm wide, apex acuminate, base broadly cuneate, margin serrate, adaxially green, abaxially pale green, sparsely pubescent on both sides, densely pubescent on mid-ribs, lateral veins 5‒8 pairs; petioles 0.5‒4.5 cm long, adaxially flat, densely white-setulose. Verticillasters axillary, (3‒)7‒14-flowered, 1.5‒3 cm in diam.; pedicels 1‒2 mm long or subsessile; bracteoles subulate, 1.5‒3 mm long, densely setuloae. Calyx tubular-obconical, 7‒9 mm long, outside densely setulose, 5-veined, 5-lobed; teeth oblong-lanceolate or triangular, 2.5‒3 mm long, apex acuminate, white-setulose. Corolla pale purple or pink, 10‒15 mm long, outside densely appressed-pilose, inside sparsely pilose, hairy-annulate on lower part; tube 6‒8 mm long, nearly straight, upper part slightly curved, amplified, with limb 2-lipped; upper lip straight, obovate-oblong, 5‒5.5 mm long, apex emarginate; lower lip 3-lobed, middle lobe broadly obovate, ca. 3.5 mm long, 2.5‒3 mm wide, apex emarginate, lateral lobes ovate, ca. 2.5 mm long, ca. 1.5 mm wide. Stamens 4, didynamous, nearly included, posterior 2 inserted in lower lip of corolla larynx, anterior 2 inserted in upper lip of corolla larynx, filaments sparsely pilose, anthers barbate, cells strongly divergent. Ovary glabrous; style slender, slightly exserted, apex 2-cleft. Disc persistent, cup-shaped. Nutlets obovoid, obtusely trigonous, gray-brown, ca. 2 mm long, apex truncate.
生活型：草本；
株：高30-70厘米；根茎匍匐，节上密生纤维状须根；
茎：茎单一，直立，钝四棱形，具四槽，棱上绿色，槽上紫色或紫红色，密被下向小刺毛状微柔毛，下部常无叶，上部具叶；
叶：叶椭圆形至长圆状卵圆形，长8-15厘米，宽4-6（8）厘米，先端锐尖，基部楔状下延，边缘有规则的具胼胝尖的圆齿状锯齿，坚纸质，上面橄榄绿色，下面较淡，上面满布下面主要沿脉上被小刺毛状微柔毛，下面有时有不明显的淡黄色腺点，侧脉5-7对，与中脉在上面微隆起下面十分突出；叶柄长0.5-2厘米，茎中部者最长，腹平背凸，略具狭翅，密被小刺毛状微柔毛；
花：轮伞花序4-14花，有时上部的轮伞花序具2花，轮廓近圆球形，开花前径1.5-2厘米，下承有少数苞片；苞片线形，长达4毫米，宽0.5毫米，外被小刺毛，内面无毛；花梗多少伸长，长1-2毫米，密被小刺毛状微柔毛；花萼管状，连齿长约7毫米，坚纸质，外面满布小刺毛，其间杂有不明显淡黄色腺点，内面在齿上被小刺毛状微柔毛，5脉，齿5，三角形，长2.5-3毫米，基部宽1.5毫米，先端刺状渐尖，常外折；
果：成熟小坚果未见；
