A small brownish anemone with a streaked column and short tentacles, found not on rock but on the shell a hermit crab is carrying - often three or four to a shell, arranged where they get the best of the current.
The partnership is deliberate on both sides. The crab picks anemones up and presses them onto its shell, working at the base until the animal releases its grip and transfers; when the crab outgrows the shell and moves, it takes the anemones with it. The anemone gains transport and the scraps of the crab's meals, the crab gains a stinging cover that deters octopus. Disturbed, the anemone fires white threads loaded with stinging cells, and a diver who lifts the shell will feel them on thin skin. Look on the larger hermit crabs of sand and rubble, especially Dardanus.
- small anemone sitting on a hermit crab's shell, several at a time
- brownish column streaked paler, short tentacles
- releases white stinging threads when disturbed
- height up to 4 cm
