Three-clawed crab

Claudette is a three-clawed crab netted by fisher Jeff Brown off the Cornish coast. She is in quarantine at the Blue Reef aquarium in Newquay for a few days and then will be put on display. From the BBC News:

The aquarium believes Claudette's ability to re-generate lost limbs became confused and, rather than replacing a missing set of claws, she grew an extra pair instead.

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