I found these crabs at the end of September, 2018. My family was vacationing on the coast of Lopez Island in the Pacific Ocean off of Washington State. I have been trying to figure out what they are ever since.

I found two crabs, one that was orange and black, and another crab that was off-white and black. They are both about an inch and a half across and an inch from front to back. I did some research and the closest match I could find are oyster crabs, which are found inside oysters on the East Coast of North America (I found my information on oyster crabs here).

However, I found these inside clams on the West Coast. Also, the pictures of oyster crabs I can find online (figure 1) do not look like my oyster crabs. I was wondering if anyone can identify these crabs. Sorry about the picture quality and thanks in advance!

A picture of an oyster crab I found online [Figure 1: A picture of an oyster crab that I found online. There are not very many pictures of oyster crabs online, and they all look similar to this one.]

Two supposed oyster crabs [Figure 2: The back of the two supposed oyster crabs I found. They are not fighting, I just put them close together for the picture.]

The front of one supposed oyster crab [Figure 3: The front of the off-white supposed oyster crab. In the picture, you can see its tiny eyes and small mouth, along with the claws.]

The front of another supposed oyster crab [Figure 4: The front of the orange supposed oyster crab. In the picture, you can see its tiny eyes, small mouth, and claws.]

The back of the orange supposed oyster crab [Figure 5: The back of the orange supposed oyster crab.]

The back of the off-white supposed oyster crab [Figure 6: The back of the off-white supposed oyster crab.]

The undersides of the supposed oyster crabs [Figure 7: The undersides of the two supposed oyster crabs. As you can see, they both have eight legs and two claws, making them crabs and part of the crustacean family.]


1 Answer 1


What you have found are pea crabs, which have a fascinating life history of parasitism. https://www.whitestoneoysters.com/blogs/an-oyster-life/what-the-shuck-is-a-pea-crab

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