Annual or biennial, up to 30 cm tall, usually branched all over, glabrous or sparsely hairy with short or minute capitate or simple hairs. Basal and lower leaves pinnatisect with short, narrow lobes, 3-5 cm long, about 1 cm broad; uppermost leaves linear or subentire. Sometimes all leaves linear, distantly short-lobed or toothed. Racemes 20-30 (-40)-flowered, ebracteate, up to c. 5 cm long (rarely more) in fruit. Flowers minute, c. 1 mm across; pedicel usually up to c. 3 (-5) mm long in fruit, often becoming subarcuate, filiform. Sepals c. 0.8 mm long, 0.5 mm broad, oblong. Petals absent or rudimentary, c. 0.5 mm long, apex subemarginate. Stamens 2 or 4 only, outer 2 always absent, inner about 0.7 mm long with very minute anthers. Siliculae 2-2.5 mm long, c. 2 mm broad, broadly elliptic, distinctly notched and obscurely or very shortly winged at the apex with almost sessile stigma included within it; septum less than 1 mm broad; seed c. 1 mm long, ovate-oblong, red-brown.

Fl. Per.: April-June

Type: From Siberia (B).

Distribution: C. Asia, Himalayas and E. Asia.

Very similar to L. ruderale L. but with many branches and more robust, usually 1-pinnatisect basal and lower leaves (not 2-3-pinnatisect), and not with so narrow sepals. L. ruderale with short, (c. 15-20 cm long) simple stem, bearing simple hairs only and crowned by short flowering and fruiting branches, is predominantly an European species,while L. apetalum with comparatively robust, much branched stem and short capitate hairs is an Asian species.