Development of Muscina stabulans at constant temperatures with implications for minimum postmortem interval estimation.

Muscina stabulans (Fallén 1817) is a disease vector and a species of forensic value, particularly in the case of buried bodies. In this study, M. stabulans was reared under a total of seven constant temperatures at 16-34 °C, and the developmental duration, accumulated degree days, and larval body length were studied. From the results, three developmental models were established for estimating the minimum postmortem interval (PMI), including isomorphen diagram, isomegalen diagram, and thermal summation model. Equations used to estimate the age of M. stabulans larvae were obtained by regression analysis using larval body length as the independent variable and time after hatching as the dependent variable, or vice versa. M. stabulans completed development at 16-31 °C, while it did not complete development at 34 °C, where puparia failed to transform into adults. The average developmental duration from oviposition to eclosion at 16, 19, 22, 25, 28 and 31 °C were 929.7 ± 31.7, 693.5 ± 4.8, 515.3 ± 4.6, 392.5 ± 9.0, 334.0 ± 7.8, 331.5 ± 4.71 h, respectively. We used a linear thermal summation model and estimated that the lower developmental threshold temperature was 9.87 ± 0.33 °C and the thermal summation constant was 253.16 ± 11.32 degree days. Lower developmental thresholds, intrinsic optimum temperature and upper lethal developmental threshold temperature were estimated by a nonlinear model to be 9.56, 21.63 and 32.85 °C, respectively. Our study provides data for the use of M. stabulans for PMI estimation.