I came across what were being sold as "Blackberry" shrimp. They are very dark blue (invisible from a distance against my black sand substrate) and some have a pretty distinct red line down the middle of them.. definitely unlike anything I've seen anywhere else. I paid $6 a piece for several adults - I normally don't pay that much for them but several of them were berried, so I couldn't resist. Just noticed babies this morning- will be selling some once the babies get a little bigger.
I breed at least a half dozen other types of shrimp as well and will be adding more regularly.