Pacifastacus

Pacifastacus is a genus of crayfish native to western North America (USA and Canada), containing six species, two of which are extinct:
 * †Pacifastacus chenoderma (fossil: Miocene – Pliocene)
 * Pacifastacus connectens
 * Pacifastacus fortis – Shasta crayfish
 * Pacifastacus gambelii
 * Pacifastacus leniusculus – signal crayfish
 * †Pacifastacus nigrescens – Sooty crayfish