2. Asystasia gangetica (Linnaeus) T. Anderson, Enum. Pl. Zeyl. 235. 1860.
宽叶十万错 kuan ye shi wan cuo
Herbs to 0.5 m tall, ascending. Stems 4-angled, pilose. Petiole 3-5 mm, pubescent; leaf blade ovate to elliptic, 3-12 × 1-5 cm, glabrous or sparsely pilose especially on veins, adaxially with numerous cystoliths, base truncate to rounded, margin entire or slightly crenulate, apex acuminate. Racemes axillary or terminal, to 16 cm; bracts triangular, ca. 5 mm, pilose; bracteoles linear-lanceolate, 1-2.5 mm, pilose. Pedicel 2-3 mm, pilose. Calyx ca. 7 mm; lobes linear-lanceolate, 5-7 × 1-1.2 mm, outside glandular pilose, margin ciliate. Corolla yellow or white, 1.2-3.5 cm, outside gland-tipped pilose, inside glabrous; tube basally cylindric and ca. 3 mm wide for ca. 8 mm then gradually widened to ca. 1 cm; lobes obovate to semicircular, 0.7-1.2 × 0.8-1 cm; middle lobe of lower lip with violet or maroon markings. Stamens included; filaments glabrous, longer pair ca. 5 mm, shorter pair ca. 3 mm; anther thecae ca. 3 × 1 mm. Ovary ellipsoid, ca. 3.5 mm; style ca. 1.8 cm, velutinous; stigma slightly capitate, 2-lobed. Capsule ca. 1.3 × 2 cm, pubescent. Seeds irregularly obovate in outline, 3-5 × 0.5-3 mm, tuberculate-rugose. Fl. Sep-Dec, fr. Dec-Mar. 2n = 26, 52.
Forest margins, roadsides. Naturalized in Guangdong, Guangxi, Taiwan, and Yunnan [paleotropical; SW Asia].
Cultivated plants of Asystasia gangetica have corollas that vary from white to cream to lavender to purple.