Habit: Annual, taprooted, glabrous.
Stem: generally spreading, branched.
Leaf: blade [oblong] ovate, +- ternate-pinnately dissected, segments thread-like to linear.
Inflorescence: umbels compound, terminal and lateral, peduncled or not; bracts 0; bractlets few, narrow; rays, pedicels 0--few, +- erect, generally +- spreading.
Flower: calyx lobes 0; petals oblong to ovate, white, tips not narrowed, not incurved.
Fruit: widely ovate, +- compressed side-to-side; ribs low, thread-like; oil tubes 1--3 per rib-interval; fruit axis divided at tip.
Seed: face grooved.
Species In Genus: 5 species: southern United States, Hawaii, southern South America.
Etymology: (Greek: seed scale, from tubercled or bristly fruit)
Jepson eFlora Author: Lincoln Constance & Margriet Wetherwax
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)
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