The signal crayfish, Pacifastacus leniusculus, is an American crayfish indigenous to the western United States. Members of this species are up to 15 cm in length. They are bluish-brown to reddish-brown in color with robust large smooth claws. They have a white patch near the claw hinge. Like all crayfish, they are solitary animals and are omnivorous, although their diet is mainly vegetarian they will eat anything from decaying roots and leaves to meat, including crayfish smaller than themselves.

Author: Madison S.