If you check out some of the dart frog forums like dendroboard, you'll find that there's a menagerie of organisms available for populating the bowels of a vivarium - probably close to a dozen species of springtails and almost as many isopod flavors. Do a little research and decide what kind of environment (theme, biotope, etc.) you want to create, and select the bugs accordingly. I personally use white and pink springtails, along with dwarf white, dwarf purple and giant orange isos, but not more than one species of each bug per tank. In my experience, unless you have a huge tank with microclimates, introducing multiple species playing the same role within an ecosystem would eventually result in all but one variety going extinct.

Millipedes could work, but even the small ones can emit a noxious substance if disturbed by your anole. And where would you get them? You have to be careful if you're bringing them in from the wild because they can carry all sorts of unwanted baddies in with them, from snail/slug eggs to mites to parasitic worms. Btw, "careful" in this instance actually means "not smart." As a general rule, you want avoid anything that can hurt or stress the anole, strip or destroy your plants, overpopulate the vivarium or cause a mess. I've also found that if I manage to maintain a healthy, vibrant vivarium for a period of time, unexpected critters will show up in there by themselves.

Best of luck.


P.S.

What the heck is a Halloween roach?