Erect or prostrate, annual or perennial herbs or subshrubs; at least the new growth hairy; leaves opposite, sessile or shortly petiolate, lamina entire, margins serrulate; stipules persistent, usually fringed, sometimes connate or united with petiole. Flowers in clusters (Victorian species) or solitary in leaf-axils; sepals 3 or 5, acute, free or shortly fused at base, keeled or winged on back, often fringed; petals equal in number to sepals; stamens 3–10, opposite sepals; ovary 3–5-locular; styles as many as locules, free or shortly united. Fruit a ± firm, ovoid to globose capsule, the chambers dehiscing along lines opposite the petals. Seeds narrowly ovoid, shortly cylindric or subreniform, smooth to trabeculate or alveolate.
About 25 species in drier tropics and temperate regions, 5 species native in Australia; 2 in Victoria.