Plants 30–100 cm. Stem hollow, branched. Basal leaves petiolate; petioles 10–38 cm, sheaths narrow-oblong; blade broadly triangular, 2–3-ternate/pinnate; basal pinnae long-petiolulate, 4–5 pairs; ultimate segments ovate to ovate-lanceolate, 1.5–2 × 0.5–1 cm, margin pinnatisect, nerves prominent on both sides. Leaves reduced upwards, Umbels 3–10 cm across; peduncles 5–15 cm; bracts 1–3, linear; rays 11–15, 3–7 cm; bracteoles 3–6, linear, shorter than pedicels; umbellules 9–20-flowered; pedicels unequal. Calyx teeth small, rounded or ovate, 0.2–0.5 mm. Petals orbicular or obovate, white, 1.5–2 × 1–1.8 mm, apex obtuse-rounded. Anthers dark purple. Fruit ovoid-globose, base cordate, 2.5–3 × 2–3 mm. Fl. and fr. Jun–Nov. n = 11*.