Unknown Crab ... ID Help ...Male & Female

[dillagas]

Found these two in the sand at a tank at my old work. Forgot I had it, and could never figure out what it was so Please help....Have looked through the usual books, and no luck, I even picked up a few of my girlfriends invertebrate bio books still no luck......maybe one of you have seen it before.

Sand in tank was wild FL keys sugar sand........awesome stuff wish we could still get it........and the rock was all Tonga branch rock......could have come in on one of the corals, but we were pretty sure it lived in the sand.

 

[Guygettnby]

hmm, interesting crabs. i have never seen them before......how big are they? they dont look to big from the pictures. do they burrow in the sand or ar they out in plain sight most the time?

 

[dillagas]

well from what I can remember we found then when we were moving so sand around in the tank, we caught them and put them in a collection cup photographed them and watched them for a while. when they were released back into the tank the smaller crab rode the back of the larger crab as dug back into the sand.

Size: On the larger (Female) Carapace Length 1cm, Total length 1.3cm

Hope it helps.

 

[LeslieH]

Those are pinnotherid crabs which normally live inside other organisms - clams are a favorite but also some snails, echinoderms, worm tubes, etc. It reminds me of Xanthasia murigera which lives in Tridacna clams (see http://www.imagequest3d.com/cgi-bin...&img=32&tt=&search=brachyura&cat=&bool=phrase)
but the arrangement of bumps on the back is different.

 

[dillagas]

yeah that looks pretty close, at least its probably in that family, we are getting closer.............