Cardamine microphylla

Perennials; usually glabrous, rarely sparsely hirtellous. Rhizomes cylindrical, slender, 0.7-1.5 mm diam. Stems erect or ascending, unbranched, 0.3-1.5(-2) dm. Rhizomal leaves pinnately 5 or 7-foliolate, (1.3-)2.5-6.5 cm, (not fleshy), leaflets petiolulate; petiole (0.5-)1.5-5.5 cm; lateral leaflets similar to terminal, blade sometimes smaller; terminal leaflet (petiolule 0.15-0.7 cm), blade ovate to elliptic, (0.2-)0.4-1.2(-1.5) cm × (1-)2.5-6 mm, base cuneate to obtuse, margins entire, (apiculate). Cauline leaves 1-3, 5 or 7-foliolate, petiolate, leaflets petiolulate or subsessile; petiole 0.2-1.5 cm, base not auriculate; lateral leaflets similar to terminal; terminal leaflet (subsessile or petiolule to 0.2 cm), blade ovate to elliptic, 0.6-1.3 × 0.1-0.7 cm, base cuneate, margins entire. Racemes ebracteate. Fruiting pedicels erect to ascending, 7-15(-25) mm. Flowers: sepals ovate to oblong, 3-4 × 1.8-2.5 mm, lateral pair slightly saccate basally; petals usually white, rarely lavender, broadly obovate, 7-10 × 3-6 mm, (clawed, apex rounded); filaments: median pairs 3-4.5 mm, lateral pair 2-3 mm; anthers oblong, 1-1.5 mm. Fruits linear, 2-3 cm × 1.2-1.7 mm; ovules 12-16 per ovary; style 1-2 mm. Seeds brown, oblong, ca. 1.5 × 1 mm. 2n = 28, 42, 64.

Flowering Jul-Aug. Streamsides, sand and cobbles on gravel bars, shale banks, floodplains, alluvial sand between cobbles, moist moss, turf, seepage areas, meadows, wet grounds; 0-1600 m; N.W.T., Yukon; Alaska; e Asia (Russian Far East, Siberia).