The optimal post-eclosion interval while estimating the post-mortem interval based on an empty puparium.

Area of Science:

• Forensic Entomology
• Forensic Science
• Insect Ecology

Background:

• Empty puparia are crucial forensic evidence for estimating post mortem intervals (PMI).
• The post-eclosion interval (PEI), the time between adult fly emergence and puparium collection, complicates accurate PMI determination.
• Understanding PEI's influence on PMI estimation is vital for forensic investigations.

Purpose of the Study:

• To simulate and analyze the impact of varying post-eclosion intervals (PEI) and temperature conditions on post mortem interval (PMI) estimations using empty puparia.
• To investigate the relationship between PEI, collection season, and PMI estimates for forensically relevant fly species.

Main Methods:

• Simulations were conducted using Protophormia terraenovae and Stearibia nigriceps puparia.
• Various PEI durations (0-90 days) and temperature conditions were modeled.
• The effect of PEI on PMI estimates was analyzed across different collection seasons (winter, spring, summer, autumn).

Main Results:

• PEI had no significant effect on PMI estimates during winter and early spring (December-April).
• In late spring, summer, and autumn (May-November), PMI estimates increased with PEI, with larger increases observed in summer.
• A PEI of 0 days consistently yielded the shortest PMI, indicating it provides the most reliable minimum PMI estimate.

Conclusions:

• The post-eclosion interval (PEI) significantly influences post mortem interval (PMI) estimations, particularly during warmer months.
• Estimating PMI from empty puparia requires careful consideration of the collection season and potential PEI.
• Utilizing a PEI of 0 days in estimations provides the most conservative and reliable minimum PMI.