Boettgerilla pallens Simroth 1912
Small to medium slug, extended length 3 – 4 cm. Pale translucent greyish-yellow, with keel from tip of tail right up to edge of the mantle; back and head darker bluish-grey. Very narrow, almost worm-like, when fully extended. Sole pale yellow, mucus colourless.
Very thin, pale and almost worm-like when fully extended.
Mostly in gardens and parks in UK, probably recently introduced in the west.
Common. Widespread and in woods in Eastern Europe.
The map provided here shows the distribution of the species based on Conchological Society data.