Twining, annual or perennial, parasitic herbs without chlorophyll, attached to the host by numerous haustoria. Stems slender, whitish, yellowish or reddish. Leaves alternate, reduced to minute scales or 0. Flowers in dense, ± sessile, spherical clusters, 4-5-merous. Sepals fused at base. Corolla usually white or pink, with 4-5-lobes fused below, usually with a whorl of scales inside the tube opposite to and just below the stamens. Stamens 4-5. Ovary 2(-3)-locular, each loculus with 2 ovules. Styles 2, terminal, distinct or connate. Capsule opening irregularly, circumscissile or indehiscent. Seeds 4 or fewer.Sometimes, as in FZ, included within its own family, Cuscutaceae, but here put with Convolvulaceae.