The majority of the diversity is found in the southeastern United States, but the genus extends as far south as Guatemala and Honduras, and on the Caribbean island of Cuba.

The subgenus Austrocambarus had the most southerly distribution, being found in Cuba and parts of Central America from Mexico to Belize, Guatemala and Honduras.

[7] Procambarus can be distinguished from other genera of crayfish by the form of the first pleopod in males, which typically has three or more processes at the tip, compared to two or fewer in Faxonius and Cambarus.

[9] Other cave-dwellers in the United States with various levels of troglomorphic adaptions are P. attiguus, P. erythrops, P. franzi, P. leitheuseri, P. lucifugus, P. milleri and P. orcinus, but these are all members of subgenera that also include species from above-ground waters.

[4] However, more recently, the subgenera have been eliminated, and while it is recognized that Procambarus is not monophyletic, later literature does not make further taxonomic changes, instead suggesting that more species sampling is required.