Dianthera japonica Thunberg in Murray, Syst. Veg., ed. 14, 64. 1784; Dicliptera buergeriana Miquel; D. crinita (Thunberg) Nees; D. japonica (Thunberg) Makino; D. uraiensis Hayata; Justicia crinita Thunberg; Peristrophe chinensis Nees; P. guangxiensis H. S. Lo & D. Fang.

Herbs 20-80 cm, perennial. Stems 4-angled, basally prostrate and rooting at nodes, bifariously pubescent. Petiole 0.5-1.5 cm; leaf blade lanceolate to ovate-oblong, (3-)5-13 × (1-) 2.5-4.5 cm, both surfaces sparsely pubescent (especially along midvein), secondary veins 3-5 on each side of midvein, base obtuse to cuneate, margin entire or slightly sinuate, apex acuminate to caudate. Inflorescences terminal or axillary pedunculate cymes from axils of distal leaves, cymes consisting of 1-4(or more) pedunculate involucres; involucres bearing 1-3 flowers; peduncle 0.7-5.5 cm; outer involucral bracteoles ovate to elliptic, subequal to unequal in size, abaxially subglabrous to puberulent, base cuneate to truncate, margin entire, apex acute to obtuse; larger outer involucral bracteoles 1.1-2.5 × 0.5-1.8 cm; smaller outer involucral bracteoles 8-17 × 3-9 mm; inner involucral bracteoles linear, 2-3 mm, abaxially puberulent, apex acuminate. Calyx ca. 4 mm; lobes subulate, pubescent. Corolla white to pale pink to light purple and with pink specks or dark lines on limb, 2-3.4 cm, outside pubescent with non-glandular trichomes; tube basally ca. 1 mm wide for ca. 1.5 cm; lip in lower position elliptic to subcircular, 8-15 × 3-11 mm, entire or slightly emarginate; lip in upper position oblong, 9-15 × 4-7 mm, 3-lobed. Staminal filaments ca. 7 mm, pubescent; anther thecae linear, ca. 1.2 mm, parallel, unequally inserted to superposed. Ovary pilose; style ca. 2 cm; stigma 2-cleft. Capsule 0.8-1.2 cm, pubescent with gland-tipped and non-glandular trichomes. Seeds ca. 2 mm in diam., tuberculate. Fl. Jul-Feb, fr. Jul-Oct. 2n = 48.

This species is used medicinally.

Roadsides, grasslands, streamsides, montane slopes, trailsides, evergreen broad-leaved forests, Machilus-Castanopsis forests; below 1500 m. Anhui, Chongqing, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Sichuan, Taiwan, Yunnan, Zhejiang [Japan].