Description
Key Characters:
Growth Form:
Evergreen vines, at least to 20 dm long, arching over other vegetation or occasionally sprawling on ground, woody at base, glabrous, puberulent in the inflorescence.
Stems:
Stems often swollen at the nodes, few–branched, terete (cylindrical).
Roots:
Fibrous root system.
Leaves:
Leaves simple.
Opposite.
Blades broadly deltate–ovate or deltate–cordate to lanceolate, 8–14 cm long, (3.3–) 4.5–6 cm wide.
Apex acute to acuminate with a short mucro.
Base leaf bases often connate around the stem, base cordate to truncate or sometimes broadly cuneate.
Surfaces sparsely puberulent along the upper surfaces midvein, the hairs 0.2–0.4 mm long, translucent to occasionally purple along the midvein, spreading to erect;, somewhat thickened and coriaceous, usually somewhat undulate; upper surfaces dark green and glossy with a slight purple tinge; lower surfaces dull green conspicuously infused with purple.
Margins entire, with scattered antrorsely curved hairs 0.1–0.2 mm long, each of these often associated with a weak epidermal protuberance.
3 conspicuous principal veins, sometimes with an additional outer, somewhat irregular pair.
Petioles 1.3–2 cm long, strongly channeled, puberulent.
Stipules absent.
Flowers:
Flowers in inflorescence terminal, with 30–164 flowers, branches 20–40 cm long, diffuse, lax, the lateral branches as long as or longer than central axis, puberulent, the hairs spreading to erect, straight to slightly crinkly, (0.15–) 0.3–0.6 mm long, on upper bracts hairs often restricted to the margins; bracts of central axis 40–80 mm long, leaf-like, deltate, those of branches and flowers 3–8 mm long, lanceolate; pedicels 7–25 mm long, terete (cylindrical).
Flowers bisexual (perfect).
Sepals 1.7–3.1 mm long, ovate, green, usually purple toward the base, thin and somewhat translucent, strongly reflexed in the proximal ¼, producing a transverse bulge, distal part strongly and deeply navicular and weakly inrolled in distal ½–2/3, oriented at 5° to 60° angle to the pedicel, sometimes the distal ½ curved outward at a 90° angle, very sparsely puberulent, occasionally some of the hairs glandular, margins scarious and sparsely ciliate in proximal ½, apex attenuate.
Corolla (petals) absent.
Stamens 10; filaments dimorphic, the antisepalous whorl 4.5–5 mm long, the alternate whorl 4–4.5 mm long; anthers 0.9–1 mm long, subequal, pale yellow.
Ovary superior, 1-celled; ovule placentation free-central; styles 3.
Fruit:
Capsules 3–3.4 mm long; subglobose to broadly ovoid.
Seeds 1.2–1.3 mm long; orbicular; compressed; transversely rugose; perisperm starchy; hard or rarely soft; true endosperm absent.
Ploidy:
Habitat:
In wet montane forest.
Elevation Range:
960–1180 m.