Five genera, 500–800 species, nearlyworldwide.

Although represented in Missouri by a small number of herbaceous species, elsewhere this morphologically variable family includes shrubs and small trees, and even succulent, cushion-forming, and liana-forming species, as well as at least one floating-leaved aquatic. Some South American Oxalis species are cultivated as food plants for their starchy tubers (see below). The carambola (star fruit), which is usually sold as a fresh fruit in American markets but can also be pickled or prepared into jams and jellies, comes from a tree species, Averrhoa carambola L., which is native to the Old World tropics but is also grown widely in the New World. The juice from both it and the other species in the genus, A. bilimbi L. (bilimbing, cucumber tree), additionally has been used as a stain remover. A number of Oxalidaceae species also have horticultural value.