Biological associations between barnacles and jellyfish with emphasis on the ectoparasitism of Alepas pacifica (Lepadomorpha) on Diplulmaris malayensis (Scyphozoa)

Ten specimens of the rare scyphozoan Diplulmaris malayensis Stiasny, 1935 h ave been found with cirripedes Alepas pacifica Pilsbry, 1907 attached to th eir surface. This association is interpreted as ectoparasitism because adul t barnacles produce deep clefts in the scyphomedusan umbrella, the gonads o f which show signs of being preyed upon by the barnacle. A review of the li terature on barnacles attached to jellyfish is presented with an interpreta tion of the meaning of this uncommon association.