Description

Key Characters:

Growth Form: Scandent to decumbent lianas.

Stems: Stems moderately short–hispidulous.

Roots:

Leaves: Leaves simple. Opposite. Blades ovate to lanceolate, 4–9 cm long, 1.2–3.5 cm wide. Apex acute to acuminate. Base subcordate. Upper surfaces rugose, moderately appressed hispidulous and glandular–dotted; lower surfaces densely glandular–dotted, occasionally also appressed hispidulous along veins; blades membranous. Margins crenate to crenulate. Petioles 1–4.5 cm long, densely long–ciliate along lateral margins, especially toward base, also sparsely to moderately appressed hispidulous. Stipules absent.

Flowers: Flowers 4(6) per verticillaster, in unbranched, elongate, terminal, racemose inflorescences 4–10(–15) cm long, pedicels 0.5–1(–1.5) mm long, bracts ovate, 7–18 mm long, lowermost pair larger, (12–)20–45 mm long, bract pubescence and glands same as that of leaves. Calyx narrowly obconical, becoming hemispherical in fruit, 3.5–5.5 mm long at anthesis, enlarging in fruit, nerves prominent, short–hirtellous and glandular–dotted, usually 5-toothed, the teeth narrowly deltate, 1.2–2 mm long, ± ciliate, apex attenuate, splitting longitudinally, usually persistent or sometimes only ventral 1/2 persistent. Corolla bilabiate, white, tinged purple toward lobes, tube narrowly funnelform, slightly curved, 8–8.5 mm long, ± sparsely short–villous and glandular–dotted, upper lip 2–3 mm long, entire or 2-lobed, flat or concave, lower lip 3.5–7 mm long, 3-lobed, lateral lobes ovate, slightly asymmetrical, lower lobe broadly ovate to suborbicular, slightly folded to form a groove, margins somewhat undulate, apex emarginate or entire; nectary disk often present at base of ovary, annular or developed on anterior side only. Stamens 4, both pairs of similar length or upper pair slightly longer, ascending the upper corolla lip, included, aligned with the sinuses; filaments inserted near throat, usually pubescent; anthers dithecal, opening by longitudinal slits; anther sacs divaricate. Ovary superior, 2-carpellate, placentation basal-axile; ovules 1 per ovary lobe; style 1, included, arising between lobes, shortly 2-lobed, the lobes clavate; stigmatic only at apex, 1 lobe often rudimentary; stigmas 2.

Fruit: Nutlets 2–2.5 mm long; 1-seeded; dark green to black; drupaceous; exocarp fleshy; obovoid; margins slightly winged; obliquely attached at the connate base; spreading and exserted from calyx at maturity. Seeds with endosperm absent or scanty and oily.

Ploidy:

Habitat: Occurring in wet forest.

Elevation Range: 640–1,190 m.