Sorry, I don't have any advice, but what part of the world do you reside in? That might be helpful for those who know!

I live in Florida, by a river, zone 9b.

Happy D Ranch has this page full of invertebrate pics and info:

http://www.happydranch.com/invertebrates/

If you click on the link for potworms, it says they aren't harmful to your worms.

Good luck!

---Amy

Here is a link that might be useful: Invertebrates

Don't worry about the worm visitors as they are harmless if they are potworms. Most of the creatures that are in our bins are harmless. The ones you describe are not a problem other than being a nusiance. You can get rid of the fruit flies if they bother you and they generally are a small problem. Do a search on fruit flies and you will find several ways to deal with them.

Thank you all. I finally get to put names to those creatures in my mini-wormbin/zoo. Yes, they are all listed in happydranch.com and I'm so relieved that they're not harmful to my "pet" redworms. :~)

rgds
bibik