Climbing shrubs or lianas, often epiphytic. Leaves alternate, entire, glabrous, mostly with hypophyllous glands. Stipules wanting. Inflorescences terminal, racemose, spicate or (sub)umbelliform. Bracts of the flowers transformed into mostly big, hollow, variously shaped nectaries. Bracteoles sepaloid. Sepals 4 or 5, thick, coriaceous, free, imbricate. Petals 3 to 5, free or united and imbricate or forming a cap. Stamens 3 to numerous, free or connate. Ovary superior, 2- to several celled, with a mostly short style and an indistinctly lobed stigma. Ovules mostly numerous. Fruit capsular, more or less woody, dehiscent, inside pulpy, with few to numerous shiny, conspicuously reticulate seeds. About 125 species in 4 genera in tropical America.