Citrus aurantifolia

The Key lime, also known as West Indian Lime, Mexican Lime, or Egyptian Lime (Citrus × aurantiifolia or C. aurantifolia) is a type of lime. While it is treated as a species in botanical classification, it originated as a natural hybrid between Citrus micrantha (a wild papeda) and Citrus medica (citron). The Key lime has thinner rind and is smaller, seedier, more acidic, and more aromatic than the Persian lime (Citrus × latifolia). It is valued for its characteristic flavor. The name comes from its association with the Florida Keys, where it is best known as the flavoring ingredient in Key lime pie. The Key lime is not to be confused with bartender's lime or the Omani lime, which are slightly different. The last is classified as a distinct race, with a thicker skin and darker green color. Philippine varieties have various names, including "dayap" and "bilolo".