Flat Porcelain Crab

Petrolisthes cinctipes

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Despite its name and appearance, the Flat Porcelain Crab is not a crab at all. In fact, it is more closely related to the lobster, but through a process known as carcinisation has evolved to look like a crab. The chief difference is in the number of legs — Porcelain Crabs only have six walking legs while true crabs have eight. Scientists still don’t fully understand why some marine animals develop crab-like characteristics, but it may an adaptation to living around and under rocks where the crab’s body shape and structure is uniquely suited.

The Flat Porcelain Crab’s unique name stems from the smooth texture and subtle colors of the carapace, which, when wet, often glistens like porcelain. These false-crabs can range in color from dark brown to sky blue.

Range and Habitat 

Species of Flat Porcelain Crabs are found in almost every ocean on Earth. Along the West Coast, they can be found from British Columbia to Santa Barbara, California. They are very common along the Oregon Coast where the rocky environment provides a perfect habitat. Often they can be seen scurrying quickly over the sand or into the surf on the state’s various beaches.

Conservation Status