The present work aims to determine the enteric helminth parasites which infest two of the most common Egyptian
freshwater fishes Clarias lazera and Oreochromis niloticus collected from different localites at Sharkia province.
Out of 554 examined fish specimens 293 (52.89%) were infested. The infestation rates were 81.27% in Clarias lazera and
23.25% in Oreochromis niloticus. Concerning the infestation with different helminth parasites among examined fish; Clarias lazera was infested with Orientocreadium batrachoides, Eumasenia degyptiacus, Polyonchobothium clarias, Monobothroides species, Botherio-ccphalus species, Procamallanus laeviconchus, P. cyathopharynx, Spinitectus
allaeri, Rhabdochona pellucida and R. aegyptiacus, while Oreochromis niloticus was infested only with Acanthosentis tilapiae. The effect of seasonal variation dynamics on the infestation rate with the different helminth parasites was also studied. The morphological characters of each parasite and single and mixed infestation in fish species were detected.
In the present study, Sharkia province is considered as a new locality for both Rhabdochona pellucida and R. aegypticus.