Un-salted Slug: Mystery

The slug wiggled under the barrage of salt. She bent over, curious, to watch it shrivel and die, but it didn't. She scowled. That was not the way it was supposed to go. The slug had turned bright purple where the salt had touched it, but it had stopped wiggling, and it didn't look like it was going to shrivel up and die anytime soon. She lifted the salt and stared at it. Salt killed slugs, simple as that, slugs that would otherwise eat her plants. This hadn't killed the slug. So it wasn't salt. In which case, what the heck was it doing in her table shaker? As if she'd suddenly found a deadly viper coiled around her spaghetti, she held it out at arms-length. It wasn't salt. It was something else. She would take it to the constable, because that is what one did--

Inspiration: I was thinking of slugs, for some reason which I can no longer remember.
Story Potential: High.
Notes: Not from this snippet, but I like the idea of a cozy murder mystery where the investigator would have been the victim. Would need to investigate what poisons would hurt a human but not immediately kill a slug, and how slugs actually react to being salted. Also, a viper coiled around spaghetti? WTF?