23. Justicia adhatoda Linnaeus, Sp. Pl. 1: 15. 1753.
鸭嘴花 ya zui hua
Adhatoda vasica Nees.
Shrubs to 4 m tall. Branches thickened, ± 4-angled, lenticellate, pubescent when young but soon glabrescent. Petiole 0.8-3 cm, puberulent; leaf blade ovate to elliptic-ovate, 7-18 × 2-7 cm, abaxially puberulent, adaxially densely tomentose when young but glabrescent except tomentose along veins, secondary veins 9-12 on each side of midvein and meeting near margin, base broadly cuneate, margin entire, apex acuminate and sometimes slightly falcate. Spikes terminal or axillary, ovoid to broadly ovoid, 3-7 cm; peduncle 3-7 cm; bracts imbricate, ovate-oblong, 1-2 × 0.5-1.5 cm, puberulent, 3-7-veined, margin ciliate, apex acute; bracteoles linear-lanceolate, 1-1.4 × ca. 0.4 cm, puberulent, 3-5-veined, margin ciliate, apex acute. Calyx 5-lobed; lobes linear-oblong, ca. 10 × 3 mm, margin narrowly scarious and ciliate. Corolla white or pink with purplish or pinkish stripes outside, broadly tubular, 2.5-3 cm, outside pilose; tube basally cylindric and ca. 5 mm wide for ca. 5 mm and then slightly inflated and bent upward; upper lip ovate-oblong, ca. 1.8 cm, erect, shallowly 2-lobed; lower lip oblong-circular, spreading, 3-lobed, middle lobe subcircular and ca. 9 × 5 mm, lateral lobes ovate and ca. 8 × 4.5 mm. Stamens exserted; filaments ca. 1.5 cm, declinate, glabrous except basally sericeous; anther thecae ellipsoid, ca. 3.5 mm, equal, superposed, lower one spurred at base. Ovary pubescent especially at tip; style ca. 2.5 cm, recurved, basal part pubescent; stigma simple. Capsule obovoid, 2.5-4 × ca. 0.5 cm. Seeds circular in outline. Fl. Jan-Mar, fr. Jun-Jul. 2n = 34.
Roadsides, thickets. Naturalized or cultivated in Guangdong, Guangxi, Hainan, and Yunnan [probably native to India, Indonesia, Malaysia, Nepal, Pakistan, and Sri Lanka, but widely cultivated and naturalized in tropics, obscuring native distribution].
Justicia adhatoda is widely cultivated beyond its native range.
This species is used medicinally.