Prestonia is a genus of plants in the family Apocynaceae, first described as a genus in 1810. It is native to Mexico, Central America, South America, and the West Indies. It is closely related to Artia and Parsonsia.Species

Apocynoideae is a subfamily of the flowering plant family Apocynaceae, also called the 'dogbane' or milkweed family, containing about 860 species across 78 genera. Several are of pharmacological interest; Strophanthus has furnished highly effective arrow poisons, due to their cardiac glycoside content. Apocynoideae also includes many popular landscaping and ornamental species, one of the best-known, and most infamous, being the oleander ; the subfamily also contains remarkable pachycaul genera like Adenium and Pachypodium.