They may look like a citrus and in fact they were at one stage considered as such but in 1915 they were reclassified as genus Fortunella.    From Wordnik.com.  [Weekend Herb Blogging #44] Reference

For the past hundred years the Nagami or Oval Kumquat (Fortunella. margarita) which is native to Japan, has been grown commercially -- with great success -- in Florida.    From Wordnik.com.  [Sugar High Fridays] Reference

Cumquat: was originally assumed to be a citrus but was later revealed to have a somewhat simpler structure than citrus and was allotted its own genus, Fortunella.    From Wordnik.com.  [Wil's Ebay E-Store] Reference

Fragola (strawberry with Balsamic Vinegar), Chocolat, Fortunella (Kumquat.    From Wordnik.com.  [TravelPod.com TravelStream™ — Recent Entries at TravelPod.com] Reference

Before we get to number 1, here are a few honorary mentions that didn’t quite make the top 10: “E. T Main Theme” by John William, “Batman Main Theme” by Danny Elfman, “Back to the Future Main Theme” by Alan Silvestri, “Psycho Theme” by Bernard Hermann, “Lord of the Rings” score by Howard Shore, and I haven’t included Nico Rota’s score from The Godfather, since he sections of it were taken from Eduardo De Filippo’s score from “Fortunella.”.    From Wordnik.com.  [Top 10 Movie Themes » Scene-Stealers] Reference