The green fly family Calliphoridae is the most important taxon in forensic entomology. These flies immediately colonize corpses immediately after death. studying insect populations including larval development is useful for estimating post-mortem times. However, the development of insects, including flies, is greatly influenced by environmental factors, one of which is geographical location. This research aims to compare the length of development of the life cycle of green fly larvae and the time difference between geographical types, namely Medan City and Berastagi City, as well as the time difference between the two. Using descriptive observational research with a prospective research design. Variables are measured at the same time as the research takes place. Research using primary data to determine the duration of the larval life cycle in each of 3 (three) samples of mice (Mus musculus) aged 2-3 months and weighing 20-25 grams at the Medan and Berastagi locations. A dislocation was carried out on the mices necks and a 5 cm incision was made on the mices stomachs and the changes in the samples were seen by examining each phase of the life cycle of the development of green fly larvae from egg to pupa and identifying the flies in the samples. There is a comparison of the development of green fly larvae of the Calliphoridae family in the Medan area and the Berastagi area. The development of Calliphoridae fly larvae in Medan from egg to imago phase is 208 hours (8.6 days) while in Berastagi it is 272 hours (11.3 days). The difference between the development of calliphoridae fly larvae between Medan City and Berastagi City is 64 hours (2.5 days).

Calliphoridae; Fly larvae; Mus musculus