Plants 1-3 m tall. Stem stout, striated, branched. Leaves 20-40 cm long, glabrous to pubescent, bipinnate; leaflets lanceolate to oval, pinnatisect; pedunc¬les 3-8 cm long. Involucre of 1 or 2 linear bracts or lacking. Rays 10-15, unequal, 2-5 cm long. Involucel of 5-6 lanceolate to oval or ovate bractlets, margins entire or ciliate, veins prominent. Petals white, outer larger. Fruit lanceolate to oblong, black, I cm long, beaked, tuberculate to hispid or bristly; furrows 1-2-vittate; vittae minute.