Annuals (winter); scapose; glabrous. Stems (sometimes absent), decumbent, branched basally and distally. Leaves basal and, sometimes, cauline; petiolate; basal rosulate, blade margins entire or lyrate-pinnatifid; cauline blade (base not auriculate), margins entire or lyrate-pinnatifid, (similar to basal). Inflorescences usually solitary flowers (on long peduncles from basal rosettes), sometimes racemes present in robust plants (corymbose, several-flowered), elongated in fruit. Flowers: sepals spreading or suberect, oblong or oblong-linear, lateral pair not saccate basally; petals white, lavender, orange, or yellow, obovate to spatulate, obcordate, or oblanceolate, (much longer than sepals), claw differentiated from blade, (much shorter than blade, apex shallowly to deeply emarginate or, rarely, truncate or obtuse); stamens strongly tetradynamous, (erect); filaments not dilated basally; anthers oblong, (apex obtuse); nectar glands: lateral annular, median glands present (distinct). Fruits siliques or silicles, sessile or shortly stipitate, linear to oblong or subglobose, torulose or smooth (or submoniliform), latiseptate, subterete, or terete; valves each obscurely veined; replum rounded; septum complete; ovules 5-25 per ovary; style distinct, (slender or stout); stigma capitate, (sometimes slightly 2-lobed). Seeds uniseriate, flattened, broadly winged or margined, suborbicular; seed coat (prominently reticulate), not mucilaginous when wetted; cotyledons obscurely accumbent, (radicle much shorter than cotyledon, straight or slightly bent). x = 11, 12, 15.