Stems (0.6-)1-2(-2.8) dm. Basal leaves: petiole 0.2-2 cm; blade lanceolate in outline, 0.5-3(-4) cm × 0.5-2.5 mm, margins usually lyrate-pinnatifid to pinnatisect, rarely dentate or entire; lateral lobes acute. Cauline leaves 0-3; blade linear. Fruiting pedicels 3-6 mm. Flowers actinomorphic ; sepals 0.2-0.6 × 0.2-0.4 mm; petals oblong, 0.5-1.5 × 0.3-0.6 mm; stamens 4, equal; filaments 0.5-1 mm (basal appendage white, ca. 1/2 its length); anthers 0.1-0.2 mm. Fruits 3-3.5 × 3-5 mm; style 0 m. Seeds 0.8-1.2 × 0.7-1 mm. 2n = 36.

Flowering Feb-Apr. Roadsides, abandoned fields; 50-500 m; introduced; Calif.; s Europe; n Africa; introduced also in n, c Europe.