Creature Feature - The Sea Slug (Nudibranch)

"When we think of slugs the image of a fat, slimy garden slug fills our mind, however under the water they become something rather special. The correct name, nudibranch, is made up from the Latin and Ancient Greek words meaning “naked” and “gills”. They are a soft bodied mollusc that sheds its shell after the larval stage, they are colourful and have amazing forms. There are over 3,000 species known at present so please let me introduce you to a local colourful resident:  the violet sea slug - Flabellina Pedata

The name gives you a clue to this one’s choice of colour as they are a bright pink/purple nudibranch. Very distinctive, they are often the first UK sea slug that divers get to recognise.  The best way to describe them is imagine a slug, along its body are cerata/projections that look a little like tassels. They are arranged in bunches and each one has a white tip. The head has two sets of forks – the top one is the rhinophores and the second the oral process or mouth, these have a white tip to them. 

Liking to stay in one place they live on the hydroids that they like to eat. A common nudibranch they are however only generally seen as individuals or mating pairs. Once mated they lay their eggs as a thin white thread that wraps around the base of their favourite food. It often the eggs that nudibranch hunters spot first…why?... the white colour against the red/orange background stands out and the egg thread is generally much bigger than the parents who are about 2cms when fully grown!! 

Divers tend to either love or hate nudibranch, but with at least 30 species to be found off the beach at Selsey, hunting these small beauties and capturing them on camera is a lot of fun."

Anya Frampton, diver, freediver & snorkeller

Posted on June 24th 2020Category: Blog