Laboratory observations revealed that both C. pipiens and C. quinquefasciatus could harbour the parasitic Hepatozoon, while only Cx. pipiens succeeded to induce infection to the recipient lizard Uromastyx microlepis. A significant reduction in egg production together with a significant increase in the pre-oviposition period of C. pipiens was recorded. Incubation period and percentage of egg hatching showed no significant changes. Infection had no effect on the reproductive fitness of C. quinquefasciatus. Haematin excretion was normally distributed for all both species. No size difference was recorded between infected and uninfected ones. Infection did not affect longevity.