DIETARY IMMUNOASSAY OF ILYANASSA OBSOLETA, THE EASTERN MUD SNAIL

¹ Department of Biology, Marine Science Program, and Belle W. Baruch Institute for Marine Biology and Coastal Research, University of South Carolina, Columbia, South Carolina 29208

The gut contents of mud snails from a high intertidal saltmarsh in South Carolina were examined both visually and immunologically from eight sample dates. Antisera to a variety of potential prey types were used in double-immunodiffusion tests of the amorphous gut material. Near absence of meiofaunal prey and presence of scant animal remains confirms the facultative carnivorous feeding mode for this species, while presence of frustules, sediments, and detritus indicated the dominance of herbivory and detritivory. Ilyanassa obsoleta is probably relatively unimportant as a predator on living benthic invertebrates, but it may be very important in detrital remineralization and physical breakdown processes.