This figure is a second figure of the Japanese silver crucian carp (or Langsdorf’s Goldfish, or Ginbuna in Japan), Carassius langsdorfii. As before, it is stamped number 16 but being a secret figure from the Book 2 second release series, it is number 17 in that list.
All Japanese Silver Crucian Carp Reviews
Japanese Silver Crucian Carp (Freshwater Fishes Book 2, second release by Yujin)

3.6 (5 votes)
Note – a lot more information has become available since I first wrote this one!
This figure is the Japanese silver crucian carp (or Langsdorf’s Goldfish, or Ginbuna in Japan), Carassius langsdorfii (according to Fishbase; earlier sources refer to it as the subspecies Carassius auratus langsdorfii ), stamped number 16 and listed as figure 1 from the Book 2 series, second.