The goldfish is similar in appearance to the crucian carp, but has only a few relatively large teeth on the long spiny ray of the dorsal fin and also has black-pigmented body tissue in the ventral cavity. Additionally, its colouring is slightly different as it has a black-grLy back and silvery, sometimes also dark or golden sides. The dorsal and caudal fins are black-grey, whilst the paired fins and the anal fin are much lighter. It lives together with the crucian carp and spawns between May and July.
The goldfish living on the boundaries of its habitat arc characterized by the following phenomena: in such places only females can usually be found, and their eggs are fertilized by other members of the carp family, especially by the carp and the crucian carp. The offspring are generally females again, and are genetically identical with the goldfish parent. The diet of the goldfish has the usual animal component with the addition of large quantities of aquatic vegetation.
Maximum size and weight: 35 cm, 1.2 kg.
Identifying characteristics: Black-pigmented body tissue in ventral cavity; spiny fin ray of dorsal fin with a small number of medium- teeth (10-15)size.
Related information: Introduction to Goldfish