Aurantioideae

Aurantioideae is a subfamily of Rutaceae, the citrus family, within the order Sapindales. It includes many genera that produce the familiar citrus fruits and their close relatives, notably Citrus, Microcitrus, Poncirus, and Fortunella (kumquats). The group is distributed across tropical and subtropical regions, with centers of diversity in Southeast Asia and Australasia.

Plants in Aurantioideae are predominantly evergreen trees or shrubs with aromatic leaves due to essential oils. They typically bear white or pale flowers in clusters, and produce fruit that is usually a citrus type—often a hesperidium—with a rind and segmented pulp.

Taxonomy within Aurantioideae has long been revised by molecular data. Traditional classifications divided the group into tribes such as Citreae and Clauseneae, but modern phylogenies recognize multiple lineages with intergeneric hybrids. This has led to varying treatments of genera such as Citrus and Fortunella, and to ongoing debates about generic boundaries and species limits.

Economic importance is high, as the subfamily contains the world's major citrus crops—orange, lemon, lime, grapefruit, mandarins—and kumquats. These species are cultivated globally for fresh fruit, juice, flavorings, and essential oils, while wild relatives contribute genetic diversity for breeding and crop improvement.