Cn-120 HERMIT CRAB HYDROID, Hydractinia sybiolongicarus

A small pink hydroid that encrusts living hermit crabs and the gastropod, Cantharus cancellarius. Polyps display an elaborate variety of growth forms, including nutritive, generative, and defensive zooids. A similar hydroid, Podocoryne carnea, may also be present. Both species take advantage of their mobile substrates by feeding on floating remnants of food or catching food particles stirred up by the host’s passage. Size of shell: 1-3 cm.