Dungeness Crab
The scientific name of the dungeness crab is Cancer magister. This crab is seldom seen south of Santa Barbara. Its claws have white-tipped pincers. Width is up to 9 inches across the back. It is red-brown to purple on top with a white to light orange underside. According to wallawalla.edu, "This crab is the largest edible crab from Alaska to California, making this species important for fisheries commercially and economically."
Red Crab
This crab's scientific name is Cancer productus. The red crab thrives in a variety of water temperatures, with a range from Alaska to San Diego. Red crabs measure up to 8 inches across the back. Its claws have black-tipped pincers. Color of the top surface is medium to dark red. The underside is yellow-white with orange to red spots. This species has powerful claws and has been known to threaten commercial oyster beds.
Rock Crab
The rock crab's scientific name is Cancer antennarius. Its most abundant range is between San Francisco and Baja California in Mexico. It measures up to 7 inches across the back. According to Animal Diversity Web, the dorsal coloration is usually deep red or brown, but varies to shades of orange or gray. The ventral side is white, with ed spotting.
Yellow Crab
This crab's scientific name is Cancer anthonyi. Its range is from Humboldt Bay to Magdalena Bay, Baja California. The yellow crab measures up to 7 inches across the back. According to the California Department of Fish and Game's website, color is yellow-brown with a purple wash anteriorly and on the legs in some specimens. Underparts are yellow or yellowish white.