Where did the first two pics come from? I know I've seen pics of a similiar one to the first blue polydesmid coming from Mexico and Central America but thats all I can say. Flat backs for some reason tend to be considerably harder to care for in captivity (although I think they also tend to have shorter life spans as well).
The flatback belongs to the family Platyrhacidae. Genus/species can only be determined by the gonopods. This family is distributed over the southeastern part of asia and middle/south of america.
The 2nd belongs to the family Harpagophoridae and I saw this pic before and it was taken in Asia, (Malaysia or the Philippines or so).
The last one is as mentioned by Greg a subspecies of A. arboreus (carribean).
I terms of avaibility/keeping: First one is hard to keep. The secretion (cyanid as in all poldesmids) is very powerfull and everything in the tank will die, even the millipede itself.
Of the 2nd excists only a picture and in my opinion can the blue colour be a result of photografing/flashlight. I heard of a blue millipede that was auctioned in Sweden for more than 200,-€
All these pics came from google image searching for new species of 'pedes. I had no clue whatsoever as to what the first could be as I'd never seen anything like that before. The second picture I had the same feeling that it may just be the camer aflash or backlighting shining against a nice shiny black 'pede, as the quality of the picture didn't seem to be too spectacular. The third actually came from the forum here, but I never saw a psitive ID in the thread it was posted in. Is it normal for Anadenobolus arboreus to have a blueish coloring to it, or is this just the particular photo?
I'm really starting to take an interest in colorful exotic millipedes. Any suggestions as to other colorfully makred and readily available (or even not so available) species collectable in north america, canada specifically for me?