A unique set of wild Citrus species native to Australia and Papua New Guinea that are commonly known as Australian limes were, up until fairly recently, considered distinct enough to be part of the separate Microcitrus and Eremocitrus genera. The various Australian lime species are noted for their small lime-like fruits with a wide variety of colors and shapes, and have only recently been cultivated.
Before European settlers arrived, the Australian lime was used as bushfood, a food source by Aboriginal Australians. Certain species and hybrids like the Australian finger lime (Citrus australasica) have juice vesicles, the flesh of the citrus fruit, that are spherical and loosely connected and lends a caviar-like appearance that can be used as a unique and colorful garnish that will release a burst of lime flavored juice when chewed. Other food uses include the making of marmalade, pickles, as well as flavoring spice from the peels.
Various cultivars and hybrids, with other citrus species, have been developed and selected that have colors that range from light pink, blood red, lime green, and deep green or blue. The variety of species and their wide genetic diversity has brought a lot of interest in discovering new selections from wild stock for eventual development for commercial growing, due to its high demand.
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