2. Ruellia repens Linnaeus, Syst. Nat., ed. 12. 2: 424; Mant. Pl. 1: 89. 1767.
楠草 nan cao
Dipteracanthus lanceolatus Nees; D. repens (Linnaeus) Hasskarl.
Herbs 15-50 cm tall, perennial, creeping. Roots lacking tuberlike swellings. Stems almost 4-angled, finely pubescent or glabrescent. Petiole 3-5 mm; leaf blade ovate to linear-lanceolate, 1.4-4 × 0.8-2 cm, thinly papery, both surfaces sparsely strigose, secondary veins 4 or 5 on each side of midvein, base broadly cuneate to rounded, margin subentire, apex acuminate to acute. Flowers axillary, solitary [or clustered]; bracteoles subleaflike, ovate to ovate-oblong, 8-10 mm. Pedicel to 1 mm. Calyx lobes lanceolate, ca. 5 mm, margin sparingly ciliate. Corolla white [or pink to light purple], 1.2-2 cm, outside pilose; tube basally ca. 2 mm wide for ca. 5 mm then ventricose and gradually widened to ca. 5 mm at mouth; lobes ovate, ca. 3 × 3 mm, apex obtuse. Stamens with longer pair ca. 5 mm and shorter pair ca. 2 mm; filaments glabrous; anther thecae ca. 1 mm. Ovary comose; style ca. 1 cm, hirsute; stigma lobes unequal. Capsule brownish yellow, stipitate, ca. 1.2 cm, slightly pilose, 12-16-seeded; septa with attached retinacula remaining attached to inner wall of mature capsule. Seeds discoid, ca. 3 mm in diam., margin with a conspicuous band of appressed hygroscopic trichomes. Fl. May-Aug, fr. Jul-Aug. 2n = 24.
Grasslands, roadsides; 100-900 m. Guangdong, Guangxi, Hainan, Taiwan, Yunnan [Indonesia, Malaysia, Myanmar, Papua New Guinea, Philippines, Thailand, Vietnam].