Description from Flora of China
Herpestis javanica Blume, Bijdr. 748. 1826; Adenosma ovatum (Wallich ex Bentham) J. D. Hooker; Herpestis ovata Wallich ex Bentham.
Stems purplish, quadrangular, decumbent or creeping, rooting from lower nodes, much branched. Petiole 2-4 mm; leaf blade ovate, 0.6-2.5 X 0.4-1.5 cm, abaxially densely with black glands, hispidulous along veins, brown when dry, adaxially sparsely hispidulous and black when dry, base broadly cuneate, margin crenate, apex obtuse. Flowers solitary in leaf axils. Pedicel 1-2 mm. Bracteoles linear, ca. 2 mm, adnate to base of calyx tube. Calyx lobes unequal; outer 3 lobes ovate, 4-7 X 2-4 mm, margin ciliate, veins evident; inner 2 lobes linear-lanceolate, ca. 4 mm. Corolla pale red, ca. 7 mm, inside hispidulous; lower lip lobes subequal, oblong, ca. 2 mm; upper lip white, narrowly elliptic, ca. 3 mm. Anterior anthers with 1 locule fertile; posterior anthers with both locules fertile. Ovary oblong-ovoid. Stigma subglobose. Capsule narrowly ovoid, ca. 5 mm, included in persistent calyx. Seeds ovoid to oblong, ribbed. Fl. and fr. Mar-Apr.
Scrub on lower mountain slopes; low elevations. Hainan [Cambodia, India, Indonesia, Laos, Malaysia, New Guinea, Philippines, Thailand, Vietnam].