Tritonia hombergii has no common name despite being readily found around most of the UK. It is our biggest sea slug or nudibranch reaching 20cms. Colour varies from white to a yellowish brown and they feed almost exclusively on the polyps of soft corals, particularly dead man's fingers, Alcyonium digitatum as in the picture. The coral poyps have all retracted in response to the attack. They are frequently seen laying an intestine-like egg coil containing many thousands of eggs. They should not be touched as they can discharge a mucous if disturbed which may cause blistering on the skin.
Seee next three pictures
St. Abbs Marine Reserve, Berwickshire. Scotland