ABSTRACT
The bean skink lizard Mabuya quinquetaeniata quinquetaeniata [Family: Scincidae] collected from Abu-Rawash, Giza was infected with the protozoon Hepatozoon gracilis. The mean percent of infection rate all over the year was 12.57% with the highest peak was in October [33%], meanwhile the lowest infection rate was detected in June [2.1%] and no infection was detected in February. Microscopical examination of experimentally infected Culex / [C.] pipiens L smears revealed the presence of gamogony and sporogony stages of H. gracilis in their haemoceal. Cx. pipiens was capable to transmit H. gracilis to non-infected M. q. quinquetaeniata under laboratory conditions [21 +/- 1 and 60-70% R.H.] after a prepatent period of 32 +/- 1 days from the infective bite. Various developmental schizogony stages were detected both in the lung endothelial cells and liver parenchymal cells. Developmental stages of H. gracilis in both vector or vertebrate host were described. Cx.pipiens was unable to transmit H. gracilis to snake, Psammophis schokari present in the same area of the bean skink lizard