Silaum silaus (L.) Schinz & Thell.

Plants 40–100 cm. Leaf blade triangular-ovate, 7–20 × 6–10 cm; lateral pinnae short-petiolulate, 2–5-lobed, terminal pin- nae 3–7-lobed; ultimate segments lanceolate to linear-lanceolate, 13–20 × 2–3 mm, abaxial veins prominent, margins cartilaginous, apex acute or acuminate, apiculate. Upper leaves 2-pinnate, narrowly linear, apical leaves reduced, segments filiform. Umbels 2.5–4 cm across; rays 5–10, 1–3 cm, unequal; bracteoles linear-lanceolate, 3–5 mm, shorter than flowers, margin scarious; umbellules many-flowered; pedicels 4–8 mm. Fruit 4–8 × 2–3 mm. Fl. and fr. Jun–Sep.

Jiangsu [native to Europe and the Mediterranean region].

Adventive in wet meadows; 100–300 m.