Citrus x aurantiifolia (Key Lime, Sublime)

The Key Lime or Acid Lime (Citrus x aurantiifolia or C. aurantifolia) is a citrus hybrid (C. hystrix x C. medica) native to tropical Southeast Asia. It has a spherical fruit, 2.5-5cm across. The Key Lime is usually picked while it is still green, but it becomes yellow when ripe.