Description from Flora of China
Torenia setulosa Maximowicz, Bull. Acad. Imp. Sci. Saint-Petersbourg 31: 72. 1887; Vandellia cavaleriei H. Léveillé; V. setulosa (Maximowicz) T. Yamazaki.
Annuals. Stems mostly procumbent, rarely ascending to suberect, branched, subquadrangular, winged at ridges, striate, setose or subglabrous. Petiole less than 3 mm; leaf blade broadly ovate to deltoid-orbicular, 4-13 X 3-12 mm, sometimes wider than long, adaxially sparsely appressed hairy, base broadly cuneate and subequal, margin with 4-6 pairs of broadly triangular teeth, apex subacute. Flowers axillary and solitary, or more often in lax racemes. Pedicel to 2 cm. Calyx to 5 mm in fruit, lobed to base; lobes linear, spreading flat at anthesis, inflexed and covering capsule with age, margin hirsute, midrib raised and hirsute. Corolla white or light purple, to 7 mm, slightly longer than calyx; lower lip spreading flat; upper lip ovate. Stamens 4, all fertile. Capsule fusiform-ovoid, shorter than persistent calyx. Seeds ellipsoid. Fl. May-Aug, fr. Jul-Nov.
Valleys, trailsides, forests, grassland; below 1100 m. Fujian, Guangdong, Guangxi, Guizhou, Jiangxi, Sichuan, Zhejiang [Japan].