Life cycle of Lucilia sericata (Meigen 1826) collected from Andean mountains

Abstract

In forensic science, fly larval size and developmental time help to estimate the time elapsed since a person has died until the body is found, generally known as minimum postmortem interval (mPMI). Lucilia sericata (Meigen 1826) is a cosmopolitan and necrophagous fly species (Diptera: Calliphoridae) that usually colonizes decomposing stages. In this study, we determined life tables parameters of L. sericata (e.g. fly survivorship, mortality and life expectancy) and developmental time of different larval stages under controlled temperatures. Cohorts of 12 eggs (12 x 10 repetitions) of L. sericata were exposed to 8°C, 10°C, 18°C, 25°C, 30°C, 35°C, and 37 ± 0.5°C. We found that larval development was not complete at 8°C and 10°C (minimum temperature limit), and at 35°C and 37°C (maximum temperature limit). The number of larvae that reached the adult stage was similar (F2,30 = 0.20, p = 0.814) at all viable temperatures (18°C, 25°C, and 30°C). We found the highest mortality to occur at initial developmental stages. Under viable temperatures, the developmental time of L. sericata from egg to adult decreases with temperature, with an average of 778 h at 18°C, 401 h at 25°C, and 288 h at 30°C. The developmental time of L. sericata at the fastest temperature (778 h) is similar to that found in Vienna (Austria), but it is 2–3 times slower than that in three cities across the United States. These results will improve the estimation of mPMIs in tropical countries across the Andes region.