Investigations into natural and experimental infections of freshwater fish by the common eye-fluke Diplostomum spathaceum Rud.

The range of fish hosts parasitized by Diplostomum spathaceum was assessed. Natural and experimental levels of infection were compared between host species. The accumulation of eye flukes with age was established in one host – Rutilus rutilus. Development of metacarcariae in lenses of naturally infected Gasterosteus aculeatus throughout the year was compared with that of experimentally infected South African clawed toads, Xenopus laevis, maintained at various temperatures (5–30 °C). The importance of temperature changes to this part of the life-cycle of the parasite is discussed.