Culms densely cespitose, 5-20 cm. Leaves: sheaths brown to straw-colored; basal leaves to 10 cm × 4 mm; cauline leaves usually 2, reduced. Inflorescences: glomerules 1-3, sessile; proximal inflorescence bract inconspicuous, brown, much shorter to ± equaling inflorescence, apex often clear, dentate; bracts deep brown, margins dentate; bracteoles deep brown, margins dentate. Flowers: tepals deep brown with narrow clear margins and apex, 1.7-2.1 mm; anthers ± equaling filament length. Capsules dark reddish to blackish, shining, spheric, 1.8-2.1 mm, usually exceeding tepals. Seeds translucent, clear brown, broadly elliptic, with few entangled hairs, 1-1.2 mm. 2n = 24.
Phenology: Flowering and fruiting summer.
Habitat: Wet, stony places on slopes and in dwarf shrub heaths in alpine and arctic tundra; circumpolar.
Elevation: 0-1200 m
Greenland, B.C., Man., Nfld. and Labr. (Labr.), N.W.T., Nunavut, Que., Yukon, Alaska, Eurasia.