In the genus Paradiplozoon, few hard structures are present therefore most of the taxonomic studies have focused on the unique ultrastructure of the sclerites. Alcohol-fixed specimens were transferred to BSA-saline for 5 min. before staining indefinitely with 5 µl WGA-TRX, 5 µl SYTO 9 and 5 µl of Cal co fluor White M2R. Rhodamine, Fluorescein and DAPI bandpass filters on the microscope enabled selective light wavelength illumination of the three flourochromes by a mercury light source. This method provided an easy and rapid methodology to show the internal sclerites of attachment clamps. It is suitable for alcohol preserved specimens and may have additional applications in other helminth organisms.

There are eight life stages in the life-cycle of Diplozoon paradoxum and limited knowledge of the life-cycle for other diplozoid genera exists. The aim of this study was to record the number of life-stages of Paradiplozoon ichthyoxanthon obtained from, Labeobarbus aeneus and Labeobarbus kimberlyensis, in the Vaal Dam from 2005 to 2007. Six larval life stages and one adult stage of P. ichtyoxanthon were identified from specimens collected in vitro and in situ. In vitro, eggs hatched after 21 days at 18°C. Eggs collected during winter were significantly larger than those laid during spring or summer. Paradiplozoon ichthyoxanthon oncomiracidia have peripheral eyes with pink pigmentation, a tubular anterior bladder-like structure, bicuspid basal pharynx valve and a branched digestive caecum and residual shell material or vitellaria in the caecum. Immature reproductive tissue connected to the ventral sucker and dorsal papillae were noted for the first time in diporpa. Large nervous ganglia and innervation of muscle were observed around the ventral sucker.

Geometric morphometric methods using computer software is a more statistically powerful method of assessing changes in the anatomy than are traditional measurements of lengths. The aim of the study was to investigate whether changes in the size and shape Paradiplozoon sp. permanent attachment clamps could be used to determine the duration of the organsism's life-cycle in situ. A total of 149 adult Paradiplozoon sp. ectoparasites were recovered from Labeobarbus aeneus and Labeobarbus kimberlyensis in the Vaal Dam. The software tool tpsDIG v.2.1 was used on six digitised landmarks placed at the junctures between the sclerites of the attachment clamps from digital micrographs. The tpsSmall v. 2.0 and Morphologika 2 v. 2.5 software tools were used to perform principal component analysis (PCA) on this multivariate dataset. The PCA analysis indicated that the increase in size and linear change in shape of the selected landmarks, were significant predictors of the sampling season. This study suggests that it takes one year for the permanent attachment clamps of a Paradiplozoon sp. to grow to their maximum size in the Vaal Dam.