Dioecious or monoecious perennial herbs or shrubs, hemiparasitic on the stems of woody plants. Stems green, brittle, often with swollen, articulated nodes. Stipules 0. Leaves opposite, simple, evergreen, often reduced to scales. Flowers minute, unisexual. Perianth segments usually 2-4. Male flowers with stamens as many as sepals; style vestigial or 0. Female flowers with short or 0 style and linear or capitate stigma. Ovary inferior. Fruit a 1-seeded berry.