Effects of the Trematode Proctoeces Maculatus on the Mussel Mytilus Edulis

Abstract

Members of the family Fellodistomatidae, like other digenetic trematodes, normally have a life cycle in which a fish hosts the adult worm, sporocysts mature in bivalve mollusks, and cercariae infect the fish. Members of the genus Proctoeces, however, have an unusual abbreviated life cycle (termed progenetic) in which both adult trematodes and sporocysts mature within the molluscan host. Adults of Proctoeces maculatus have been found in the kidney of the bivalve Scrobicularia plana (Fr eeman and Ll ewel lyn, 1958) and in Mytilus edulis (Stunkard and Uzmann, 1959). When we discovered a population of M. edulis in Lewes, Delaware, infected with P. maculatus, we decided to study the seasonality of inf ection and the histopathology associated with the infection. This is a preliminary report of the first 10 months of this study.