@david71 .. We have a similar fruit in Australia called Tangelo which is a x between a tangerine and a grapefruit. A tart but delicious taste. A search of tangerine will give you a myriad of hybrids of the delicious tangerine crosses most of which I find delicious.
We also have what we call "Bush Tucker". Bush tucker, also called bushfood, is any food native to Australia and used as sustenance by the original inhabitants, the Aboriginal Australians, but it can also describe any native fauna or flora used for culinary and/or medicinal purposes, regardless of the continent or culture. Some of these fruits are staple delights of the indigenous Australians and are fast becoming incorporated in to mainstream local cooking and consumption