Olea ( OH-lee-ə) is a genus of about 40 species in the family Oleaceae, native to warm temperate and tropical regions of the Middle East, southern Europe, Africa, southern Asia, and Australasia. They are evergreen trees and shrubs, with small, opposite, entire leaves. The fruit is a drupe. Leaves of Olea contain trichosclereids.For humans, the most important species is by far the olive (Olea europaea), native to the Mediterranean region, Africa, southwest Asia, and the Himalayas, which is the type ...