Kumquat
Species of small fruit-bearing tree
Kumquats, are a group of small, angiosperm, fruit-bearing trees in the family Rutaceae. Their taxonomy is disputed. They were once classified as forming the historical genus Fortunella or placed within Citrus, sensu lato. Different classifications have assigned them ranging from a single species, Citrus japonica, to numerous species representing each cultivar. Recent genomic analysis defines three pure species, Citrus hindsii, C. margarita and C. crassifolia, with C. × japonica being a hybrid of the last two.