What I can tell you, is that it wasn't freshly molted. It also hasn't been long since it's last molt, since it has sharp toes. It's not soft, or deformed, or weak. It was strong enough to draw blood with it's feet trying to get away when I was taking pictures!
Unfortunately it was her husband who took the crab, and he didn't ask any questions, so we don't know if the crab has always been colorless, or if this was a new development, or what it had been eating. She knew for certain that it had been set up properly several years ago as she went over care with the woman and sold her everything she would have needed to do it right. If the woman comes back in she'll ask, but we're not sure we'll ever get an answer.
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In daylight on the ride home, no flash.
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Under normal florescent lights, with flash.
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Under UVB light, with flash.
There isn't a stitch of color on it. Even it's antennas are practically translucent. My husband keeps saying it's albino, and I was blowing him off for a while, but when I googled albino crustacean, it really does look like an albino lobster.... https://goodmorninggloucester.wordpress ... -8th-2012/
I'm going to keep it separated until it molts, just to be on the safe side. I've also got a UVB light on the tank for the heck of it. I guess we'll have to wait to see what happens, but he's seriously got me scratching my head! He's bizarre. The photos don't do him justice - he's sort of see-through and iridescent and the shade of blue (which I'm assuming is his blood!) of his antenna and underside are stunning.