The iyokan (伊予柑 - Citrus × iyo), also known as anadomikan (穴門みかん) and Gokaku no Iyokan,[1] is a Japanese citrus fruit, similar in appearance to a mandarin orange, with Dancy as the pollen parent and Kaikokan as the seed parent.

[3] Iyokan was discovered in 1886 in the orchard of Masamichi Nakamura, a resident of Yamaguchi Prefecture.

The skin is very shiny and brightly colored and, once peeled, the flesh gives off a very strong scent.

[citation needed] There is a variation grown into a pentagon shape to promote good luck and to revive the popularity of the fruit,[6] also giving it another nickname, Gokaku no Iyokan, which translates into "Pentagonal Iyokan"[7] It is sometimes placed into fish feed to mask the fishy flavor.

[8] In Japan, the citrus can be seen during springtime as a seasonal KitKat flavor with messages of "good luck" to students studying for exams on each packet.