A lime is a citrus fruit, which is typically round, lime green in colour, 3–6 centimetres (1.2–2.4 in) in diameter, and contains acidic juice vesicles. There are several species of citrus trees whose fruits are called limes, including the Key lime, Persian lime, kaffir lime, finger lime, blood lime, and desert lime. Limes are a rich source of vitamin C, are sour, and are often used to accent the flavours of foods and beverages. They are grown year-round, originally in tropical South and Southeast Asia but now in much of the world. Plants with fruit called "limes" have diverse genetic origins; limes do not form a monophyletic group. This photograph shows two limes grown in Brazil, one whole and one halved, and was focus-stacked from 23 images.