BORNMUELLERA Hausskn., Mitth. Thüring. Bot. Vereins, ser. 2, 11: 71 (1897).

Subshrubs or suffruticose perennial herbs with woody, few- to several-branched caudex, densely to sparsely pubescent or subglabrous. Trichomes sessile, medifixed, malpighiaceous (2-rayed) or stellate and 3–6-rayed, with the longest rays parallel to the long axis of the organ carrying them, simple trichomes absent. Multicellular glands absent. Stems erect to ascending, simple and leafless to several or numerous branched and leafy, not spiny. Basal leaves petiolate, rosulate, simple, entire, fleshy or not; cauline leaves sessile and cuneate to attenuate, not auriculate at base, entire. Racemes several or many flowered, ebracteate, corymbose, slightly or rarely considerably elongated in fruit; rachis straight; fruiting pedicels divaricate, glabrous or pubescent, persistent. Sepals ovate, free, deciduous, ascending to spreading, equal, base of lateral pair not saccate; petals white, ascending tor spreading, longer than sepals; blade obovate, apex obtuse or rounded; claw strongly differentiated from blade, often much shorter than sepals, glabrous, unappendaged, entire; stamens 6, slightly exserted or included, strongly curved at base, tetradynamous; filaments wingless, basally 1-appendaged, glabrous, free; anthers, ovate, apiculate; nectar glands lateral, 4 and one on each side of lateral stamen, sometimes 2 and ringlike or U-shaped and surrounding or subtending lateral stamens, median nectaries absent; ovules 1–4 per ovary; placentation subapical. Fruit unsegmented capsular silicles, dehiscent and obovoid to ellipsoid, slightly inflated and terete or very slightly latiseptate, or fruit samaroid, indehiscent, suborbicular to broadly obovate, emarginate, and strongly latiseptate; valves thin or thick papery, veinless or obscurely reticulate-veined, glabrous, smooth, wingless, unappendaged; gynophore absent; replum rounded, visible or rarely slightly concealed by valve margin; septum complete, membranous, veinless; style obsolete or to 0.5 mm long, persistent; stigma capitate, entire, unappendaged. Seeds aseriate, narrowly winged all around, partially margined, or wingless, ovate, slightly flattened; seed coat smooth, not mucilaginous when wetted; cotyledons accumbent.