Summary
Optical and electron microscope studies of the supposed epitheliocystid Ochetosoma aniarum cercariae indicated that the bladder epithelium was syncytial and did not develop from a “mesodermal” mass as previously noted for epitheliocystid worms. The initial development appeared similar to that described for other epitheliocystid cercariae, except that the lining was cytoplasmic in all stages of development. The bladder epithelium of mature cercariae possessed spongiform secretory granules, nuclei in outpockets distal to the lumen, and appeared secretory in nature. The bladder wall of early embryos did not appear secretory, however it became progressively more secretory appearing as the embryos matured. These findings do not uphold the criteria established by La Rue (1957) for epitheliocystid development, thus casting doubt upon the research that led to La Rue's conclusions.
The protonephridial ducts were similar to those described by others. The larger duct walls possessed finger-like projections into the lumen. Such projections were not seen in the small excretory capillaries.
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Powell, E.C. Optical and electron microscope studies on the excretory bladder of the supposed epitheliocystid cercaria of Ochetosoma aniarum . Z. Parasitenk. 40, 19–30 (1972). https://doi.org/10.1007/BF00329612
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DOI: https://doi.org/10.1007/BF00329612