Description from Flora of China
Koelzia K. H. Rechinger.
Herbs perennial with a woody caudex or herbaceous base. Trichomes simple. Stems branched from caudex and above, sometimes woody at base. Basal leaves absent. Cauline leaves petiolate, dentate, uppermost sometimes entire. Racemes ebracteate, elongated in fruit. Fruiting pedicels slender, ascending, suberect, or reflexed. Sepals oblong, caducous, base of lateral pair not saccate. Petals white, longer than sepals; blade spatulate or oblong-obovate, apex rounded; claw purple, subequaling sepals. Stamens 6, tetradynamous; filaments not dilated at base; anthers oblong, apiculate at apex. Nectar glands confluent and subtending bases of all stamens; median glands present. Ovules 10-20 per ovary. Fruit dehiscent siliques, linear, oblong, or lanceolate, latiseptate, sessile; valves papery, with a distinct midvein, glabrous or puberulent, torulose; replum rounded, covered by connate valve margin; septum complete, membranous, translucent, veinless; style obsolete, rarely to 0.5 mm; stigma capitate, entire or slightly 2-lobed. Seeds uniseriate, wingless, sometimes distally appendaged, oblong, slightly flattened, often transversely oriented in locule; seed coat minutely reticulate, not mucilaginous when wetted; cotyledons incumbent.
Two species: Afghanistan, China, Kashmir, Nepal, Pakistan, Tajikistan; two species (one endemic) in China.