Distribution areas of freshwater crayfish in Greece. Astacus astacus: red areas and circles; Austropotamobious torrentium: green area; Astacus leptodactylus: blue line and squares (translocations); Pacifastacus leniusculus: diamonds (introductions, translocation and range expansion); mixed distribution zone of A. astacus and A. torrentium: hatched area. Original layers from www.geodata.gov.gr.