Wikipedia
Cherry Orange
Cherry Orange (Citrus kinokuni ex Tanaka) is a variety of Mandarin orange, found in Southern China and also grown in Japan where it is known as Mukaku-Kishu. It is not closely related to the common orange.
The fruit is also known as Baby Mandarin, Tiny Tangerine and Mini Mandarin, all are given names of the same species and hail from the same unique geographical area. It is shaped like an orange, between 25 and 50 mm in diameter. The fruit's orange skin is thin and smooth. It is almost seedless, tender, sweet and extremely juicy.