Stained smears of Culex neavei females infected with Hepattozoon matruhensis from Psammophis schokari and kept at 20 +/- 1 degrees C showed the complete developmental stages of the parasite. However, no detection of sporozoites was monitored when females were kept at 30 +/- 1 degrees C. A successful infection of P. schokari was carried out in the laboratory by C. neavei bites. The effect of infection on the mosquito longevity was insignificant (p>0.05) under low temperature and highly significant (p<0.001) under high temperature. The mortality rate was slightly affected at 20 +/- 1 degrees C, but greatly affected at 30 +/- 1 degrees C.