Citrus sinensis x (Citrus paradisi x poncirus trifoliata):
Succory Orange x (Duncan Grapefruit x Poncirus trifoliata)
This was an experimental cross in an attempt to make a hardy, sweet, edible orange.
As it still has it's experimental number and not a name, one can only assume that it was never meant to be released into the wild.
We are so glad it was though as it is reputed to be one of the hardiest oranges available with sweet Orange like fruits.
A hardier Citrus fan's must have.