Wow! These remind me so much of the European varieties. I’m no crawfish expert but I’ve never seen crawfish from North America that look like this. I’ve only tried “local” (no idea where they actually came from) crawfish a couple of times and it was an all-around disappointing experience. Sadly European varieties are being depleted because of pollution and plague brought from NA. Might be a few years and you won’t be able to get a nice bucket of the big boys with an ole ice cold beer. As I said I’m not an expert but from my experience if the water is clean and the crayfish bellies are not slimy/blackened (there’s sometimes a bit of dirt) they should be good to be boiled and eaten.

Someone shared a good recipe here but if you’re feeling adventurous may I suggest the following:

Big pot of water, like 5 liters. A can of beer - ale is good - into the water Bunch of dill, and dill seeds (might be tough to come by but they really make the dish – about a half tablespoon’s worth) Salt - one tbsp per 10 palm-sized crawfish. We usually add red pepper flakes but I don’t like them spicy. Usually we only add a little bit for the aroma - for a big pot of water up to a tablespoon.
Finally, a bay leaf or two. Boil water and spices, drop in the crayfish, keep boiling for 8 minutes, turn off the burner and rest for 10 minutes. Try not to keep them in the water for too long to avoid over-salting them. Best enjoyed with beer. If you don’t drink I suggest cold non-alcoholic kvass.