Annuals; glabrous or pubescent. Stems erect, branched distally, (2–)4–12(–16) dm, sparsely to densely hirsute basally, glabrous or glabrate distally. Basal leaves rosulate; petiole 1–10(–15) cm; blade broadly oblanceolate, oblong, or lanceolate (in outline), (2–)5–20(–35) cm × (10–)20–80(–100) mm, margins pinnatisect, pinnatifid, or runcinate; lobes (3–)4–6(–8) on each side, oblong or lanceolate, smaller than terminal lobe, margins entire, dentate, or lobed. Cauline leaves similar to basal; distalmost blade with linear to filiform lobes. Fruiting pedicels usually divaricate, rarely ascending, stout, nearly as wide as fruit, (4–)6–10(–13) mm. Flowers: sepals ascending or spreading, oblong, (cucullate), 4–6 × 1–2 mm; petals spatulate, (5–)6–8(–10) × 2.5–4 mm, claw 3.5–6 mm; filaments 2–6 mm; anthers oblong, 1.5–2.2 mm. Fruits narrowly linear, usually straight, smooth, stout, (4.5–)6–9(–12) cm × 1–2 mm; valves glabrous; ovules 90–120 per ovary; style 0.5–2 mm; stigma prominently 2-lobed. Seeds 0.8–1 × 0.5–0.6 mm. 2n = 14.
