User blog comment:StealthSimmons/I hate being a completionist/@comment-4661596-20140306221200

I kinda have a similar problem, some critters are abundant, but some are just really rare. i have gotten one glowing snail, I saw one of each of the scorpions, but they both got killed by mummies, and i haven't seen the tree nymph butterfly. I also have never seen a worm, and I think i heard a mouse once or twice, but couldn't find it. You could try checking around your npc houses for the butterflys or also try the ends of the map.