Perennial, dioecious or monoecious herbs, or herbs with flowers bisexual (not in Victoria). Rhizomes creeping or tufted, covered (at least when young) with closely appressed scales. Stems erect or rarely scrambling, green, terete or slightly flattened, usually smooth, glabrous, unbranched or branched; hollow portion of stem pith circular. Leaves reduced to sheathing bracts, 6–42 mm long. Inflorescence axillary, often confined to distal axils, sexes similar, made up of several clusters of flowers. Flowers not in definite spikelets, each subtended by 1 or 2 floral bracts; perianth of 6 membranous (glume-like) parts, usually longer than floral bracts. Female flowers with staminodes usually 3; ovary 3-locular and 3-angled; styles 1–3. Fruit a capsule.
Endemic, with 22 species occurring in all States except NT; 3 species in Victoria.