Virginia Institute of Marine Science
Proceedings National Shellfisheries Association
Dermocystidium marinum hypnospores, obtained by exposure to thioglycollate (the Ray technique), were isolated from oyster tissue and placed in sea water under aerobic conditions. The cells differentiated into sporangia, and sporulation occurred by successive bipartition of the protoplast, resulting in the formation of motile cells within the hypnospore wall. The planonts escaped through one or two preformed discharge pores and tubes. All motile cells were biflagellated with both flagella attached laterally and subapically. The anterior flagellum had Flimmern and the posterior flagellum was a whiplash. The planont cell body was intermediate between reniform and pyriform. Sporulation morphology is discussed from light microscope studies. Infection of oyster organ and tissue explants was accomplished with motile cells from single sporangia and from populations of sporangia. Living oysters were infected with the hypnospore isolates, but it was not determined which cell type gave rise to the infections — hypnospores, prehypnospores, or planonts.
Perkins, Frank O. and Menzel, R. W., Morphological and cultural studies of a motile stage in the life cycle of Dermocystidium marinum. (1966). Proceedings National Shellfisheries Association, 56, 23-30.