Glaucilla marginata Bergh, 1860

Glaucilla marginata

sub-classs Opisthobranchia > order Nudibranchia > sub-order Aeolidina > family Glaucidae

Dark blue on top and light underneath. Most nudibranchs are bottom dwellers and live foot down. Glaucilla live on the surface with their foot upwards. If turned over they will quick revert to their original position. They feed on bluebottles and can extract the poisonous nematocysts and store them for their own protection

Distribution =  worldwide, temperate and tropical waters.
Max size =  at least 35mm long


more info at Sea Slug Forum      more pics at nudipixel