Yes- it's bad news when a slug arrives. I have been told a low dish with beer in it attracts them and then gets rid of them but I've never tried it. I sometimes find slugs in our wood pile but thankfully never on the plants. Good shot none the less!
Oh, for heaven's sake! I hope it either hightailed it out of there (Ha! I can just see a slug rushing away) or you nabbed it. Nice color to finish January and head into FOR February.