5. Oenanthe thomsonii C. B. Clarke in J. D. Hooker, Fl. Brit. India. 2: 697. 1879.
多裂叶水芹 duo lie ye shui qin
Plants 20–50 cm, weak, diffuse. Roots fascicled or fibrous. Stems slender, creeping, branched. Leaves homomorphic, 3–4(–5)-pinnate; primary pinnae 5–7 pairs; ultimate segments short linear, 2–3 × 1–2 mm. Umbels 3–8 across, frequently leaf-opposed; peduncles elongate, 2.5–10 cm; bracts absent; rays 4–12, 1.5–3.5 cm, unequal; bracteoles 5–7, linear, 1.5–4 mm; umbellules 15–20-flowered; pedicels 3–5 mm, unequal. Styles ca. 1 mm, reflexed. Fruit subglobose, ca. 2 × 1.5 mm; dorsal and intermediate ribs protruding, filiform. Fl. Jul–Aug, fr. Sep–Oct.
Moist shaded areas among shrubs and trees, marshy meadows, moist grasslands, river banks, streamsides; 1000–3500 m. Chongqing, Guangdong, Guizhou, Hubei, Jiangxi, Sichuan, Xizang, Yunnan [Bhutan, India, Myanmar, Nepal, Sikkim, ?Vietnam].