Western-asia
Guides
Astacidae
Astacid Crayfishes, Freshwater Crayfish
Astacidae is a family of freshwater crayfish comprising four extant genera: Astacus, Austropotamobius, Pontastacus, and Pacifastacus. Members are native to Europe, western Asia, and western North America. The family is distinguished by a gonopore positioned on the coxa of the third pair of walking legs in males (fifth pair in females), a trait shared with all Astacoidea. Several species, particularly Pacifastacus leniusculus (signal crayfish), have become invasive outside their native ranges, carrying crayfish plague (Aphanomyces astaci) that threatens native European populations.