Development of Phormia regina at seven constant temperatures for minimum postmortem interval estimation

Area of Science:

• Forensic Entomology
• Diptera Taxonomy
• Developmental Biology

Background:

• Phormia regina is crucial for estimating the minimum postmortem interval (PMImin).
• Existing developmental data for P. regina shows discrepancies, necessitating refinement of PMImin indicators.
• Accurate developmental data is vital for reliable forensic entomological evidence.

Purpose of the Study:

• To investigate the accuracy of forensic entomological evidence using P. regina development.
• To establish refined developmental models for P. regina to improve PMImin estimation.
• To provide accurate developmental models applicable to common case-site temperatures in northern China.

Main Methods:

• Studied P. regina development at seven constant temperatures (16-34 °C).
• Measured development durations, accumulated degree hours, and larval body length.
• Established isomorphen diagrams, thermal summation models, and body length simulation equations.

Main Results:

• Developmental durations ranged from 840.8 hours at 16 °C to 222.5 hours at 34 °C.
• Determined the lower threshold temperature (TL) at 9.97 °C and thermal constant (K) at 5052.7 degree days.
• Optim SSI models yielded lower developmental thresholds (13.15 °C), optimum temperature (21.20 °C), and upper lethal threshold (36.86 °C).

Conclusions:

• The study provides refined developmental models for P. regina.
• These models enhance the accuracy of minimum postmortem interval (PMImin) estimation.
• The findings are particularly relevant for forensic investigations in northern China.