Development of the green bottle fly Lucilia illustris at constant temperatures

•Lucilia illustris is a forensically important species for postmortem interval (PMI) estimation.•The development of L. illustris is monitored from 15 to 35 °C.•Three developmental models are constructed that can be used to estimate PMImin.•The developmental threshold temperature and thermal constant were obtained.

Lucilia illustris (Meigen 1826) (Diptera: Calliphoridae) is a cosmopolitan species that commonly colonizes carcasses and occasionally acts as parasites of humans or livestock, making it an insect of significant importance in forensic, medical, and veterinary entomology. However, only a few studies have documented the development of L. illustris. Here, we studied the developmental duration and larval body length changes of L. illustris under nine constant temperatures ranging from 15.0 to 35.0 °C. Using these results, we generated an isomorphen diagram, thermal summation model, and isomegalen diagram for L. illustris. Simulation equations of the variation in the larval body length with time after hatching and variation in time after hatching with the body length were also obtained. L. illustris could complete its life cycle in 15.0-32.5 °C, while its development was incomplete at 35.0 °C, where the pupae failed to transform into adults. The development duration was 955.5 ± 16.9, 625.7 ± 16.9, 509.3 ± 18.3, 410.0 ± 17.0, 346.7 ± 12.2, 290.2 ± 6.7, 257.1 ± 8.9, and 234.8 ± 3.2 h at 15.0, 17.5, 20.0, 22.5, 25.0, 27.5, 30.0, and 32.5 °C, respectively. The developmental threshold temperature and thermal constant were 9.30 ± 0.19 °C and 5367.2 ± 98.3 °C h, respectively. These results provide an important basis for the use of L. illustris development-based estimation of the minimum postmortem interval (PMImin) in forensic entomology.