Description

Key Characters:

Growth Form: Scandent subshrubs.

Stems: Stems retrorsely villous to retrorsely strigose.

Roots:

Leaves: Leaves simple. Opposite. Blades ovate, 5–13 cm long, 2.5–6 cm wide. Apex acuminate. Base cordate. Surfaces villous (hairs more dense and often somewhat longer along veins, those of Upper surfaces also somewhat appressed), very sparsely glandular–dotted; blades somewhat rugose. Margins crenate. Petioles 1.2–5.5 cm long, retrorsely villous. Stipules absent.

Flowers: Flowers 6 per verticillaster, in unbranched, open, terminal racemose inflorescences usually 10–15(–20) cm long, pedicels 0.5–2 mm long, villous, bracts broadly ovate, 8–15 mm long, villous, subsessile, lowermost pair larger, 17–50 mm long. Calyx narrowly obconical, 4–6 mm long at anthesis, enlarging in fruit, nerves ± prominent, antrorsely villous and short–hispidulous, also very sparsely glandular–dotted, usually 5-toothed, the teeth broadly ovate to deltate, 1–2 mm long, villous especially along veins and margins, apex acute, splitting longitudinally, usually persistent or sometimes only ventral 1/2 persistent. Corolla bilabiate, pale pink to pink, rarely white(?), tube 8–12 mm long, narrowly funnelform, sparsely villous, upper lip ca. 3.5–4.5 mm long, entire or 2-lobed, flat or concave, villous, lower lip ca. 9–11 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 unknown. Seeds with endosperm absent or scanty and oily.

Ploidy:

Habitat: Very rare in diverse mesic forest to wet forest.

Elevation Range: 915–1,100 m.