Citrus aurantifolia, also known as Mexican or key lime, is a shrub-like evergreen tree native to tropical Southeast Asia. It produces smaller, more aromatic fruit than the related Citrus x latifolia, or Persian lime, which is more commonly available in the United States as a culinary fruit. Lime essential oil has a sharp, green, citrus aroma that uplifts the senses when used aromatically or applied topically.