The Sea Lemon Sea Slug is a large oval-shaped sea slug that is quite flat-looking.  It has its name the ‘Sea Lemon Sea Slug' because of its lemon yellow colouring.   It can be found around most of the coasts of England in shallow waters, but it can also be found in off-shore waters as deep as three hundred metres.  It can easily be overlooked because it likes to hide under large rocks.

The Sea Lemon Sea Slug can grow up to twelve centimetres in length and although it is usually a yellow colour it can also be white, pink, green or brown with darker blotchy markings.  The top part of this sea slug’s body is covered in wart-like bumps and it has two finger-like antennae at the front of its body.  At the rear end of the body it has eight feathery gills that stand up from the body.  It uses the feathery gills to breathe through.

Sea Lemon Sea Slugs are ‘hermaphrodites’ which means they are both male and female. Sea Lemon Sea Slugs  lay their eggs in ribbon-like masses which are attached to rocks in a coil shape.  The larvae hatch out in the sea where they become part of zooplankton for around three months.  Then they settle on the seabed to develop into adult Sea Lemon Sea Slugs.