The morphology of associations between a trematode (Megalodiscus temperatus) and bacteria

Abstract

Rod-shaped bacteria are associated with the tegument surface and cecum of Megalodiscus temperatus (Stafford, 1905). Some bacteria appear to be attached to the tegument by a finely filamentous material while others are partially embedded in the tegument. The depressions occupied by the bacteria can be seen in micrographs taken with both transmission and scanning electron microscopes. The association between the bacteria and the cecal epithelium is not so intimate, although occasional depressions in the surface of the epithelium appear to result from the presence of bacteria.