Decumbent perennial herb with stems to c. 50 cm long, usually at least partly rooting at lower nodes, often much-branched and with a longitudinal row of hairs on 2 opposite sides. Lvs usually shortly petiolate, 1-4-(6) cm × 2-8 mm, linear to narrow-oblong, narrow-elliptic or oblanceolate (shape may vary on the one plant), glabrous or almost so, entire or obscurely denticulate; base attenuate; apex obtuse to subacute. Fls in dense, sessile, axillary, ± globular heads, 5-8-(10) mm diam. Bract and bracteoles much < perianth, white or pinkish white, scarious. Tepals unequal, 2-3 mm long, white, scarious, with soft apex; longer tepals linear-lanceolate or lanceolate, acuminate; shorter tepals ± ovate, ± acute. Fertile stamens 2-3; staminodes minute. Utricle ± 1.5 × 2 mm, light brown, strongly compressed laterally, broadly obcordate; margin thickened. Seed c. 1 mm diam., shining.