Description: Herb, to ca 1 m tall, puberulose; rooting at nodes. Leaves opposite, ovate-oblong to lanceolate, 4–16 x 3–9 cm; base cunete; apex cuspidate; blade puberulose on both surfaces; margins dentate; secondary nerves 4-7 on each side; petioles 2–5 cm long. Inflorescences axillary or terminal, corymbose, densely flowered, 4-5 cm in diam. Flowers in pairs, pedicels 1–2 mm long, ebracteoles. Calyx tube ca 1 mm long, puberulose; lobes 4-5, linear, ca 2 mm long. Corolla creamy white, tubular, 0.5-1 cm long, puberulose outside; lobes 4, rounded, 1-2 mm. Stamens 2, inserted at the middle of corolla tube; filaments ca 1 mm long; anthers dorsifixed, ca 2 mm long. Disc tubular with crenate margin. Ovary inferior, bilocular, ovules numerous; style filiform, ca 5 mm long; stigma clavate. Capsule dry, pyramidal, ca 3 x 7 mm, 2-valved. Seeds numerous, black, ovoid, ca 1 mm long, reticulate. |
| Distribution: Distributed in India, S China (Yunnan), Vietnam and Sumatra. In Thailand recorded from Chiang Rai (Mae Sai), Nan (Doi Phukha), and Loei (Na Haeo), in montane forest, 1,200–1,700 m. |
