Annual, greyish herb with stellate-dendroid hairs, up to 30 cm high, branched from the base, the alternate forking branches often giving it a spherical tumble-weed shape; stem and branches stellate and long hairy, densely so in the lower parts. Leaves alternate, opposite or in whorls of 3 at the crotches, linear-filiform to linear, entire cuspidate, 1-nerved, lower 5-25 (-50) x 2-5 (-10) mm with a short mucro; upper leaves or female bracts much narrower, ± long cuspidate, covered with stellate hairs, long unbranched jointed hairs sometimes arising from the centre of the stellate hairs. Perianth of staminate flowers oblong-ovate, with obtuse lobes, sparsely covered with fugacious stellate hairs. Ovary densely stellate-hairy, hidden within bracteoles. Fruiting bracteoles oblong-obcuneate, (3.5-) 5-7 x 2.5-4 mm, with a longitudinal nerve on each side and with straight spreading subulate spines, up to 5 mm long, at the margins and apex.