Perennial, c. 1 m tall, glabrous. Root thick, elongated, woody. Stem branched, angular. Lower leaves c. 30 cm long, bipinnate; upper pinnate; pinnae 1-2 cm long, lobed, ovate, glabrous; margin sharp toothed. Umbels terminal and lateral. Involucre of 1-12 linear bracts or lacking. Rays 20-50, glabrous to bristly. Involucel of numerous linear to lanceolate, pubescent bractlets. Pedicels pubescent. Calyx teeth linear, pubescent. Petals white. Ovary densely pubescent. Fruit oblong, dorsally compressed, 4-5 mm long, pubescent; ridges prominent, elevated; furrows 1-vittate; commissure 2-vittate; vittae large.