There is a narrow pink line round the margin of the parapet and the oral disc and tentacles are white.
This has the effect of increasing the volume of the shell available to the hermit crab which can then inhabit it for a longer period before needing to find a new home.
[1] On the lower part of the column there are specialist cells which emit defensive pink (occasionally white) threads called acontia if the animal is disturbed.
[5] It occurs wherever its hermit crab host is found, in deep water on sandy flats and particularly favours muddy gravelly bottoms with shell fragments.
At first the larva develops in the same way as a typical sea anemone, but as it grows, its base extends around the gastropod shell until the two lobes meet at the upper side of the lip.
The species of shell the anemone chooses varies, and has included Buccinum undatum, Scaphander lignarius, and various Trochidae.
[7] The anemone has been kept in an aquarium for an extended period on a rock substrate [8] and in 1969, Maynardi and Rossi found a single example of the hermit crab Pagurus excavatus carrying, on its gastropod shell, a specimen of A. palliata and another of Calliactis parasitica.