Oct 19, 2008

Covered with Barnacles

Neil photographed this meta-crustacean on the beach at Cayucos, CA. It's a purple shore crab (Hemigrapsus nudus), covered with barnacles.

Did you know that barnacles are crustaceans? I didn't, until Neil told me. Turns out there are 1,800 or so species of the sessile suspension feeders. I agree with Neil's assessment that the barnacles didn't pick a very good place to settle. They'll be cast aside when the crab molts. When will barnacles ever learn?

Thanks for the crab, Neil.





















Here's a picture of my own hand holding what might just be a purple shore crab. But since there are a variety of small crabs that inhabit the western shores of North America (from British Columbia to Baja California), I can't be certain. The little crab was cast back into the tidal pool from whence it came.

9 comments:

Maskdt said...

Sheesh, talk about persistent hitchhikers...

Anonymous said...

Looks like a green crab to me. Non-native, they are an unwelcome addition to the West coast's fauna. They make great bait.

T and S said...

The first one is a beautiful closeup shot

nonspecific said...

Huh. I didn't know either. I thought they taught us in school that crustaceans had five pairs of legs...

Neil said...

Decapods (crabs, lobsters, shrimp etc.) usually have five pairs of legs, but they are only a small subset of crustacean diversity albeit the most familiar subset. Krill, copepods, amphipods, ostracods and isopods (e.g. woodlice, slaters, rolly-pollies) are just a few of the other more familiar, non-decapod groups.

Elizabeth said...

Actually, I'm pretty sure that's a Hemigrapsus. Can't tell from this angle if it's oregonensis or nudus, but it's not a green.

Denita TwoDragons said...

Hmm, I totally didn't know that barnacles were crustaceans! I love learning something new! :-)

--TwoDragons

Anonymous said...

If you're squeamish, you might not want to read about another crab/barnacle relationship where the parasitic Sacculina barnacle invades the crab's body and literally takes over its mind and body.
http://www.damninteresting.com/?p=53
http://www.hku.hk/ecology/porcupine/por23/23-invertebrates.htm#index5

booge said...

Stupid barnacles! They're either on a crab's ass, or getting crabs from promiscuous sex, or shooting up in a Greyhound bathroom. No amount of education can get through to these nitwits. I say, 'Good day!'