Okay if those are adults then my next best guess is Chowanoke crayfish (Orconectes virginiensis). Rostrum has correct shape, Aerola is correct, cervical spine correct. For a positive ID one needs to see the gonopods of the first form males. Orange tips on the claws are missing compared to the photos on ncwildlife website. Color of claws can be variable depending on habitat and food source.
Are the number of antenna a good feature to use as an identifier?
If so, the Chowenoke has 4 small antenna and two large.
My crayfish (all examples) have two small and two large.
Never realized those little buggers were so hard to identify!
