Copepod - Doridicola agilis

From P. J. Hayward J. & S. Ryland (2003)

Characteristics:

The body length is usually no more than 1-2 mm. To the naked eye it looks like one or three colored blobs. In the latter case, you are looking at a female with two bags of eggs. The color is usually red, brown, orange, yellow or white.

Habitat:

These are parasites, often observed on nudibranchs.

Distribution:

It is quite common in the North Sea, including Norway, the British Isles and the coasts of central Europe.