Nespole or Loquat is native to southeastern China and possibly southern Japan, though it is possible that it was introduced to Japan long ago. It is said to have been grown in Japan for over a thousand years. In Europe, is a very popular fruit that can be found in any fruit store or supermarket. Rosaceae, as it is known in Japanese, it is Nespole Giapponese to Italians, and Néflier du Japon to French-speaking people.
I should also mention that part of the reason you won’t find this fruit in the United States is that it doesn’t ship well and thus isn’t available in most supermarkets. They quickly go from green to ripe to rotten.
They have a large seed inside and are pale orange in color, slightly larger than an apricot. The peel is edible and has a tangy flavor, though most people avoid eating it because it is fuzzy and can stain fingers.
They have a mango and apricot flavor to some people