Suckerlop eggs can only hatch if they are completely immersed within water for the entire duration of the egg stage. The water must be 23.32 degrees Celsius exactly. Because of the precise conditions that are required to hatch Suckerlop eggs, they are very rare.
Suckerlops are incredibly beautiful fish, exclusively found in the North Sea. Despite their captivating appearance, they are terrifying creatures. Albeit small, Suckerlops have razor-sharp teeth that can tear through human flesh, among many other things (including hard rock). They also have a loud roar that can be heard from miles away, similar to a whale.
For obvious reasons, a Suckerlop has never been caught.