Fumaria incisa Thunberg, Nova Acta Acad. Sci. Imp. Petrop. Hist. Acad. 12: 104. 1801; Corydalis incisa var. alba S. Y. Wang; C. incisa var. koreana Fedde; C. incisa f. liuchiuensis Nakai; C. incisa f. pallescens Makino; C. incisa var. pseudomakinoana Fedde; C. incisa var. tschekiangensis Fedde.

Herbs, annual or biennial, green (or glaucous?), 10-40(-60) cm tall, glabrous. Taproot simple (annual [and ?biennial] form) or swollen to radishlike tuber ca. 1 × 0.5-1 mm (biennial form). Stems leafy and branched from base, erect to suberect, angular-sulcate. Lower petioles 5-15 cm, upper 1-4 cm; blade 3-9 × 3-9 cm, bi- to triternate; primary leaflets petiolulate; ultimate leaflets sessile, rhombic, 1-1.5 × ca. 1 cm, broadly cuneate, deeply dentate with sharp teeth; uppermost leaves smaller and sometimes grading into lowermost bract. Raceme 3-12 cm, 6-17-flowered, at first dense, then lax; bracts rhombic, 4-6(-10) mm, with sharp incised teeth. Pedicel (5-)9-15 mm, only slightly elongating in fruit. Sepals 1-2 mm, cut to base into few narrow lobes. Flowers usually pale pink or purple, with purplish red or purple apex; inner petals darker at tip but crest white. Outer petals truncate to emarginate, with short abrupt crest not reaching apex; upper petal 16-22 mm; spur nearly straight, cylindric, 8-10 mm; nectary 1/4-1/3 as long as spur; lower petal base usually with shallow sac. Stigma rectangular, with 4 simple marginal papillae; geminate papillae lateral and in basal corners. Capsule oblong, 12-18 × 2.5-3 mm, 6-12-seeded; style ca. 2.5 mm. Seed very finely reticulate (visible with strong lens), 1.8-2.1 mm, keeled, elaiosome small. Fl. and fr. Apr-Sep.

The annual form seems to be more common in the north.

Forest margins, roadsides, wastelands, along irrigation channels; sea level to 1800 m. Anhui, Fujian, SE Gansu, NE Guangxi, Guizhou, S Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, S Shaanxi, S Shanxi, Sichuan, Taiwan, Zhejiang [Japan (including Ryukyu Islands), Korea].