The symbiosis between the «cloak anemone» Adamsia carciniopados (Otto) (Anthozoa-Actiniaria) and Pagurus prideauxi Leach (Decapoda-Anomura)

Abstract

Behavioural interactions between Pagurus prideauxi and its symbiotic anemone Adamsia carciniopados (= A. palliata)) were studied. Small juvenile and adult hermits without anemones displayed a strong drive to acquire Adamsia but they lost this drive when one Adamsia had been obtained. Stealing of Adamsia occurred in small juveniles but was rare after the anemones became firmly settled on shells. Earlier reports that the pagurid actively feeds the anemone were not confirmed. Transfer of Adamsia by the pagurid from stones to shells was accomplished by “squeezing” movements repeated at constant intervals whose frequency is temperature-dependent. Adamsia did not climb on shells but the pedal disk adhered to any surface, more rapidly after being manipulated by the pagurid. Attacks on P. prideauxi by octopus were delayed and sometimes repulsed by Adamsia. Comparative aspects of the symbiosis are discussed.