Description from Flora of China
Herbs, annual, glaucescent throughout, glabrous except the setulose fruit. Taproot slender. Stem erect, slender, profusely branched. Basal leaves petiolate, base with narrow membranous wing; blade 2-ternate; ultimate segments filiform. Leaves reduced upwards, becoming sessile. Umbels lax, terminal and lateral; bracts and bracteoles several, similar to leaves but more cartilaginous, apex subulate, persistent; rays and pedicels very unequal. Calyx teeth subulate, conspicuous, unequal, persistent in fruit. Petals white or pinkish, obovate or oblong, base cuneate, with a small inflexed lobule. Stylopodium conic, attenuate into styles; styles short, reflexed. Fruit oblong-ellipsoid, slightly laterally compressed; primary and secondary ribs prominent, setulose; vittae 1 in each furrow under secondary ribs, 2 on commissure. Seed face slightly concave. Carpophore 2-parted
Four species: N Africa, C and SW Asia, Mediterranean region, North America; one species (introduced) in China.
(Authors: Pu Fading (溥发鼎 Pu Fa-ting); Mark F. Watson)