Annual or perennial herbs or dwarf-shrubs. Stems prostrate. Leaves opposite, the upper sometimes alternate, sessile or subsessile, with small scarious stipules. Flowers small, hermaphrodite or unisexual, in dense, axillary clusters. Calyx lobes (4-)5. Petals 5, short, subulate-filiform. Stamens 2-5. OvaryA 1-celled, with 1 basal Ovule, borne on a long funicle; style 2-partite to 2-fid. Fruit a subspherical utricle, exserting from or included in calyx. Seeds globular to lenticular, blackish, shining.