Cardamine niigatensis H. Hara, J. Jap. Bot. 58: 328. 1983. TYPE:

            Herbs, perennial. Rhizomes short, creeping, somewhat thickened. Stems (3–)5–15(–20) cm, erect, glabrous or sparsely pubescent, branched above. Cauline leaves (lower) 1.8–5 cm, trifoliolate or 5-foliolate, glabrous; terminal leaflet orbicular to lanceolate, 0.5–2.3 cm, 0.5–2.5 cm wide, base truncate or obtuse, margin obtusely few toothed, apex rounded; lateral leaflets elliptic to oblong, 2–10 mm, 1–7 mm wide, base cuneate, margin enite, apex subacute to obtuse; upper cauline leaves simple or trifoliolate, 2–5 cm; blade or terminal leaflet subsessile or short petiolate, elliptic, lanceolate, obovate to orbicular, 1.5–4 cm, 0.8–4 cm wide, base obtuse or subtruncate, entire of crenately 1- or 2-toothed on each side; lateral leaflets obovate to elliptic, 0.5–2 cm, 0.3–0.8 cm wide. Racemes ebracteate; fruiting pedicels 1–1.5 cm, ascending.

Sepals 2–3 mm, 1–1.5 mm wide, glabrous; petals white, 4–7 mm, 2.5–3.5 mm wide; filaments 2.5–3.5 mm. Fruits linear, 2–3.5 cm, ca. 1.2 mm wide, glabrous; style 1–2 mm. Seeds 1–1.2 mm.

Flowering: Apr–May.

Habitat: wet places along streams.

Elevation: 0–1000 m.

Distribution: Japan (Honshu).