Description

Key Characters:

Growth Form: Scandent vines.

Stems: Stems climbing, to 1–2 m long, weakly 4–angled, tomentose.

Roots:

Leaves: Leaves simple. Opposite. Blades narrowly ovate to oblong–ovate, 6–14 cm long, 2.5–4.8 cm wide. Apex acute. Base obtuse to truncate. Surfaces densely tomentose (hairs spreading), Blades membranous, somewhat flaccid. Margins crenate to subentire. Petioles 9–18 mm long, densely hirsute. Stipules absent.

Flowers: Flowers 3–6 per verticillaster, axillary, pedicels 7–10 mm long, densely tomentose. Calyx bilaterally symmetrical, upper lip 3-lobed, lower lip 2-lobed, campanulate, 12–23 mm long, enlarging in fruit, hirsute, the teeth acute, 3–8 mm long, 4–6 mm wide at base, splitting longitudinally, usually persistent or sometimes only ventral 1/2 persistent. Corolla bilabiate, tube whitish or pale yellow, lip pinkish purple, corolla lobes sparsely tomentose externally, tube narrowly funnelform, strongly falcate, ca. 27–42 mm long, upper lip ca. 9–18 mm long, entire or 2-lobed, flat or concave, lower lip ca. 5–7 mm long, 3-lobed, the lobes flat or margins revolute, ovate, of similar size, distal portion of corolla sparsely to densely pubescent externally, the hairs simple or multicellular, occasionally glandular pubescent within, otherwise glabrous; 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, included within corolla or well–exserted beyond upper lip; filaments inserted near throat, pubescent; anthers dithecal; anther sacs divaricate, opening by longitudinal slits. Ovary superior, 2-carpellate, each carpel longitudinally divided, placentation basal-axile; ovules 1 per ovary lobe; style 1, exserted, arising between lobes, usually cleft, diverging after anther dehiscence, shortly 2-lobed, the lobes subulate; stigmas 2.

Fruit: Nutlets ca. 9 mm long; 1-seeded; drupaceous; black at maturity; margins slightly winged; obliquely attached at base; included within calyx at maturity; exocarp fleshy; obovoid. Seeds with endosperm absent or scanty and oily.

Ploidy:

Habitat: Known from a single population consisting at present of 3–4 individuals in diverse mesic forest.

Elevation Range: 700–750 m.