Description from Flora of China
Carum flaccidum (C. B. Clarke) Franchet; Pimpinella duclouxii H. de Boissieu.
Plants annual, 30–60 cm, slender, sparsely puberulent. Taproot, 4–8 × ca. 0.3 cm. Stem branched from base. Basal petioles 0.5–3 mm; blade 1–2-ternate or 1-pinnate, pinnae 2 pairs; ultimate segments oblong-ovate or broad-ovate, 4–5 × 3–5 cm, margins crenate or coarsely serrate. Cauline leaves similar to basal, smaller, 3-lobed, lobes lanceolate. Umbels 2–3.5 cm across, spreading; bracts and bracteoles absent; rays 2–6, 0.5–2 cm, glabrous; umbellules 4–7 mm across, 2–8-flowered; pedicels 0.5–2, elongating to 10 mm in fruit. Calyx teeth obsolete. Petals white, obovate or ovate, apex with incurved lobule. Stylopodium low-conic; styles ca. 1 × stylopodium. Fruit ovoid, ca. 1 × 1 mm, base cordate, surface glabrous (occasionally papillose); vittae 3 in each furrow, 4–6 on commissure. Seed face plane. Fl. Apr–Jun, fr. Jul–Sep. 2n = 20*.
Specimens attributed to this taxon have been confused with Trachyspermum scaberulum. Further work is needed to clarify the status of this Indian species in China.
Forests, among shrubs, grassy slopes, alpine meadows; 2200–3800 m. W Sichuan, NW Yunnan [NE India].