Arabis planisiliqua

Arabis planisiliqua is a slender, biennial or short-lived perennial herb of the Brassicaceae native to central, southern and southeastern Europe, the Balkans, the Caucasus and parts of southwestern Asia, where it grows on calcareous grasslands, open rocky slopes, scrubby woodland margins and sunny stony banks at low to middle elevations. It develops a basal rosette of oblanceolate to spathulate leaves 2-7 cm long, somewhat hairy with simple, branched and stellate hairs, and with shallow teeth along the margins. The erect, branched or simple flowering stem grows 20-70 cm tall and bears numerous sessile, lanceolate, sagittate-clasping cauline leaves that are entire or remotely toothed. The terminal raceme carries small four-petalled cruciform flowers 4-7 mm wide with white to creamy-white petals about twice as long as the green sepals. The fruits are conspicuously flattened, linear, slightly torulose siliques 3-7 cm long and 1.5-2 mm wide, held on short, erect-ascending pedicels and containing a single row of small, narrowly winged seeds in each locule.