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Odd Crustaceans

Crustacean evolution has gone in odd directions (odd for my fish-centric mind). The stiff carapace of crabs and shrimps has allowed evolution to mold it in a particularly extreme number of shapes and forms, to fulfill adaptive functions from camouflage on the surface of larger invertebrates, camouflage in the sand, to maximum mechanical stability.

In recent weeks I had the chance to film some very unusual crabs. The best crab encounters in the Philippines I always have during night dives, when many crabs, now more safe from predation by fishes, come out.

In this video I filmed a crab which had such an extremely modified body, covered in sand, so that I am wasn’t even remotely certain what the genus or species of the animal is. According to Dr.  Jo Wolfe, via Twitter, the animal belongs to the Parthenopidae.

 

In this video, just after the urchin-snappers (video starts at 3:15), a decorator crab put such a massive log on its head  that it barely could walk around with it. while the log likely protected the crab, it must also draw attention to the animal’s presence.

I hope you enjoyed the videos,

Best Fishes (and crabs!),

Klaus