Platypetalum purpurascens R. Brown, Chlor. Melvill., 9, 50. 1823; Braya arctica Hooker; B. purpurascens (R. Brown) Bunge ex Ledebour; B. purpurascens var. dubia (R. Brown) O. E. Schulz; P. dubium R. Brown

Stems ascending to erect, 0.3-1 (-1.3) dm. Leaves: blade often fleshy, to 4 mm wide, margins usually entire, rarely 1 or 2 weak teeth per side. Racemes not elongated in fruit (often compact). Fruits oval-elliptic to oblong-elliptic, usually straight, 0.5-1 cm × 1.5-3 mm, 2.5-3.7 times as long as wide; style slender or stout, (0.3-)0.5-1.2 mm. 2n = 56.

Flowering Jun-Jul. Barren, usually calcareous soils and gravel on solifluction lobes, scree, gravel bars, disturbed sites, rocky slopes, seashores; 0-1800 m; B.C., N.W.T., Nunavut; Alaska; n Eurasia.