Annual, 5-10 cm, glandular-pubescent. Stems many, greyish-green, branching from the base. Leaves 5-15 x 1 mm, linear, acute, almost spiny, usually 7-nerved, with 3 prominent veins, ciliate at the base. Flowers in congested dichasial cymes. Pedicels shorter than the calyx. Calyx campanulate. Sepals 5-6 mm, unequal, lanceolate-acuminate, with scarious indurated margins, glandular-pubescent, 3-nerved. Petals white, ovate oblong, shorter than the calyx. Capsule oblong, shorter the calyx. Seeds finely tuberculate.