Annual, climber or trailer. Tendrils slightly pubescent, 3-6-fid. Stem 5-angled, finely hairy to glabrous. Leaves palmately 5-lobed, dark green, orbicular-cordate, 8-25 cm across, lobes triangular, lanceolate, acute-apiculate, entire or sinuate, scabrous. Petiole 5-15 cm long. Flowers bright yellow, pedicellate, 5-6 cm across; male racemose, racemes axillary, 12-25 cm long, 15-20-flowered, female flowers in the same axil as males. Probrract fleshy, ovate, with 3-7 glistening glands on the upper surface. Calyx tube short, broadly campanulate, slightly pubescent; lobes triangular-lanceolate, longer than tube. Petals obovate-cuneiform, 2.5-3.5 cm long, 1-2.5 cm broad, obtuse. Stamens 3-5, filaments 6-8 mm long. Ovary cylindrical, finely appressed hairy. Fruit cylindrical and fusiform, 20-50 cm long, 6-10 cm across, smooth. Seeds dull black, elliptic-ovoid, c. 10-12 mm long, 6-8 mm broad, with c. 1 mm wide margin.