Calliactis is always attached to shells of hermit crabs, mostly in the genus Dardanus. Reportedly the anemone's stinging cells help protect the crab from predation by octopus. The mobility of the crab, in return, helps keep the anemone away from anemone-eating starfish predators such as Culcita and Acanthaster.
The anemones below have their tentacles retracted. The one on the left looks like Sagartiomorphe carlgreni.
Created 20 April 2025