Deciduous vines, 2-5 m, glabrous. Root tuberous, huge, exposed, brown and rough on surface, light brownish yellow inside. Branches and leaves containing red juice. Petiole usually 3-5(-8) cm; leaf blade rotund to triangular-rounded, length and width 5-9 cm, papery, densely papillate or adaxially inconspicuously papillate, base truncate or slightly emarginate, apex cuspidate, obtuse, with a finely mucronate acumen, palmately ca. 10-veined. Inflorescences compound umbelliform cymes, axillary or on short axillary branches with reduced or no leaves; peduncle 6-8 cm; umbellet pedicel 0.5-2 cm, slightly curved at end, with a few linear bracteoles; both cymelet pedicel and flower pedicels very short. Male flowers: sepals 6 in 2 whorls, outer whorl oblanceolate-spatulate, ca. 1.2 mm, inner whorl broader, abaxially papillate; petals 3, purple, conchiform, with basal sides inflexed, slightly shorter than sepal; synandrium ca. 0.5 mm, anthers 6. Female inflorescences unknown. Female flowers unknown. Infructescences slightly dense compound umbelliform cymes; umbellet pedicel usually less than 1 cm. Endocarp obovoid, ca. 6 × 5 mm, with columnar ornamentation short, apically slightly curved and hooklike. Fl. Mar.