Pachygrapsus crassipes, known as the striped shore crab or lined shore crab, is a small crab found on rocky and hard-mud shores of the west coast of North to Central America and in the western Pacific in Korea and Japan. In North America, its range spans from Vancouver Island to Baja California, Mexico. The Asiatic population appears to not be invasive but endemic, resulting from a divergence estimated between 0.8 to 1.2 Mya. Typically, this crab will have a brown/purple or black carapace with green stripes. Its carapace is square and can reach 4 to 5 cm in size. The claws are red/purple with a mottled pattern on the upper surface, and white on the lower surface, while its legs are purple and green with a similar mottled appearance.