10.22376/ijpbs.2019.10.1.p1-12 Volume 4 Issue 1 2013 (January - March) Any deviation in ambient temperature causes stress and disturbs the cellular homeostasis in the organisms. In the present study, genotoxicity induced by exposure of high temperature (40º, 45º and 50ºC) has been analyzed in the third instar larvae of common housefly, lessThan i greaterThan Musca domestica lessThan /i greaterThan , by using chromosome aberration assay, micronucleus assay and mitotic index as cytological end points. The adverse effects of heat stress on development pattern of housefly were also observed. A significant (p lessThan 0.05, p lessThan 0.01 and p lessThan 0.001) increase in chromosome aberrations and micronucleus frequency was observed in all the exposed groups as compared to control. Cell proliferation at 50ºC is inhibited as represented by a decrease in mitotic index. The development pattern in exposed larvae shows increase in larval mortality and delay in adult emergence. The results suggest that heat stress induces structural chromosome aberrations, micronuclei and affects development pattern in housefly lessThan i greaterThan Musca domestica lessThan /i greaterThan . NIDHI MISHRA, RAGHAV RAM TEWARI AND RASHMI SRIVASTAVA Chromosome aberrations, Development pattern, Micronucleus assay, Mitotic index, Musca domestica. 455-468