Description

Key Characters:

Growth Form: Perennial vines.

Stems: Stems up to 15 m long and 4 cm in diameter, annual stems sparsely pubescent, glabrate, black–spotted.

Roots:

Leaves: Leaves simple. Alternate. Blades broadly ovate–cordate with a narrow basal sinus, 7–25 cm long, 6–26 cm wide, shallowly to deeply 3–5–lobed, the lobes broadly ovate–triangular. Apex of the central lobe acute or short-acuminate, apex of the lateral lobes obtuse. Upper surfaces glabrous; lower surfaces densely hispid or puberulent. Margins denticulate. Petioles 2.5–7 cm long. Stipules absent; tendrils in the stipular position 2–branched.

Flowers: Flowers in staminate flowers in sparsely to densely pubescent panicles 8–25 cm long, peduncles 6–20 cm long, pedicels 3–10 mm long, glandular puberulent; pistillate flowers 2–6 per head, subsessile on peduncles 2–8 cm long. Flowers usually unisexual (and the plants monoecious or dioecious), actinomorphic. Calyx of 5 sepals; sepals, inserted on hypanthium. Corolla of staminate flowers greenish yellow, 5-lobed, 4–5 mm in diameter, petals inserted on hypanthium alternate with calyx lobes, usually connate at base, the limb often rotate; Corolla of pistillate flowers 5-lobed, perianth usually smaller than in staminate flowers. Stamens in staminate flowers (2)3(–5), inserted at base of hypanthium; filaments connate into a column; anthers curved or flexuous, coherent and twisted in a head, opening by longitudinal slits; pistillate flowers: staminodes absent. Ovary inferior, of a single carpel or 3-carpellate with carpels connate into a single 3-lobed cell; ovule 1, placentation parietal; stigma 3-lobed.

Fruit: Fruit green; ovoid; 13–18 mm long; 4–6 mm in diameter; 5–6–ribbed; often obscurely so; minutely puberulent; usually beaked; indehiscent. Seeds 1 per fruit; ovate; endosperm absent.

Ploidy:

Habitat: Apparently rare in wet forest and subalpine forest; on the windward slopes.

Elevation Range: 1,200–2,000 m.