This is one of the new kids on the block. I used to look after a few hundred Limax. They enjoyed a nightly feed of birdseed, wholemeal bread and grated cheese (It was actually being put out for the birds but the Limax are opportunists). The last couple of years there has been an influx of Arion and the Limax population has decreased dramatically. I have to admit I did chuckle when MrsG recently opened the back door and almost received a post-coital Arion in her face. It was hanging off the door frame by a mucilaginous rope just at the appropriate height. Its ex-partner was heading off at speed ( relatively speaking) down the side wall.
This little chappie/ lady/ thingy was found on top of the Sphagnum house this morning, enjoying a snack of wholemeal bread a bird had dropped there.