Please help ID this crab

Fish & Invertebrate sightings and descriptions, hosted by resident NWDC ID expert Janna Nichols (nwscubamom).
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aviddiver.her
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Please help ID this crab

Post by aviddiver.her »

I don't think I've ever seen this one before. The only crab ID book I have is Gotshall and it doesn't have anything with a carapace that is segmented like this. (I'm waiting for Christmas to get my Jensen Crab and Shrimp ID book). I took this in Northern California at Russian Gulch State Park in Mendocino county.
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Here is a WA of it in it's environment.
Here is a WA of it in it's environment.
Here it is cropped in closer.
Here it is cropped in closer.
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John Rawlings
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Re: Please help ID this crab

Post by John Rawlings »

:uh: Looks like it's both dead and upside down to me. The carapace isn't visible.
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aviddiver.her
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Re: Please help ID this crab

Post by aviddiver.her »

Well now, upside down would explain a lot of things :biggrin: . Like why the "carapace" is segmented, and why it's claws are on the bottom and why it let me take so many photos without it running away. But then, when it didn't run off I considered if it might be dead and saw it moving it's claws and legs so decided it was alive. We had very little surge but I suppose it is possible the surge moved the legs and fooled me #-o but I don't know :dontknow: . If you look at this other image it does not have that bit of white "stick" running from it's little claw to the main body like it did in the first one. I'm not sure if it is actually holding that thing in the first or if it is an optical allusion. Also, when I look at all of the photos and lighten them up I can't see any evidence of a carapace underneath in the shadows. Of course, if it is dead it may not have a carapice.
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Scott G
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Re: Please help ID this crab

Post by Scott G »

its probably an upside down pacific rock crab- cancer antenarrius... maybe cancer branneri...
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Greg Jensen
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Re: Please help ID this crab

Post by Greg Jensen »

It's a Cancer antennarius- the red spotting on the underside is a distinctive feature. Could just be a molt flopping in the 'breeze', with the carapace missing.
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