These are succulent shrubs and trees, often growing as epiphytes. The leaves are oppositely arranged. The inflorescence is a terminal cluster or sometimes a solitary flower. The flowers are large, showy, and fragrant. They are white, fading yellow. They open at night and dry out and die the next day. The fruit is a woody capsule containing papery winged seeds.
Four species are recognized as of May 2014:
- Cosmibuena grandiflora (Ruiz & Pav.) Rusby - Costa Rica, Nicaragua, Panama, Guyana, Suriname, Venezuela, Bolivia, Colombia, Ecuador, Peru, Brazil
- Cosmibuena macrocarpa (Benth.) Klotzsch ex Walp. - Costa Rica, Nicaragua, Panama, Colombia, Ecuador
- Cosmibuena matudae (Standl.) L.O.Williams - Chiapas, El Salvador, Guatemala, Honduras, Nicaragua
- Cosmibuena valerioi (Standl.) C.M.Taylor - Costa Rica, Panama