欧泽芹 ou ze qin

Plants 70–150 cm. Roots fibrous. Submerged leaves 2–3-pinnate; ultimate segments linear. Aerial leaves 1-pinnate; pinnae 2–6 pairs, leaflets lanceolate or oblong, 4–7(–16) × 0.8–2 cm, margins serrate. Upper leaves reduced, smaller; leaflets linear-lanceolate or linear. Umbels 6–12 cm across; peduncles elongate; bracts 2–6, linear-lanceolate, 3–5 mm, entire; rays 8–10(–30), 1.5–2.5 cm, unequal; bracteoles several, similar to bracts, 5–6 mm; umbellules 15–25-flowered; pedicels 2–3 mm. Calyx teeth minute, ca. 2 mm. Styles ca. equal to stylopodium, reflexed. Fruit ellipsoid, ca. 3 × 2 mm; ribs filiform, thin-corky; vittae 3 in each furrow, 2–5 on commissure. Fl. Jul–Aug, fr. Sep–Oct. 2n = 20.

Marshlands, stream banks; 400–500 m. Xinjiang [Kazakhstan, Russia; C Asia, Europe; introduced in Australia].