The anemones on this crab's shell did not settle there. The crab put them there.
When it changes shell it goes back for them. It strokes and taps the base of each anemone with its claws and legs until the anemone lets go - which it does willingly, softening its grip in response to that particular handling and to very little else - then lifts it across and holds it against the new shell until it takes hold. Moving a full set can take an hour or more, and the crab will spend that hour rather than leave them behind.
The trade is straightforward. The anemone gets carried to new feeding ground and picks up the crab's scraps. The crab gets a shell covered in stinging cells, and an octopus that would otherwise work the shell open goes and finds something easier.
It is a large hermit crab, up to about ten centimeters, red and hairy-legged with blue-ringed eyes on long stalks, and it works over reef flats, rubble and sand at night for carrion, algae and anything small enough to take.
- hairy red legs and claws with pale tips
- eyes on long stalks, ringed with blue
- shell usually carrying one or more sea anemones
- left claw larger than the right
- up to 10 cm
