There are several types but talking to guys who have breeder ponds for golds, gupps, and such down south they say it is not uncommon to find local crays in there holding tanks. So that opens up a wide door.
Looks like a Marble Crayfish / Procambarus Marmokreb for sure. These are quite interesting little crays. I just picked up two myself and will probably have some for sale in the near future for anyone looking to pick some up. From what I understand they stay relatively small...aprox 2-3 inches full grown, but don't quote me on that. They are pretty fun to watch in a tank. Keep me informed if anyone is looking for these in the near future. I'm sure to have some available. One last thing...don't introduce these into local water ecosystems...they could wipe out other crays or over populate the waters quickly. Be responsible.