A body is found outdoors in summer with masses of third-instar blowfly larvae (Calliphora species) present. Knowing that egg-to-third-instar development takes approximately 72–96 hours under local temperature conditions, what is the MINIMUM postmortem interval?
- A 24 hours
- B 72 hours ✓
- C 48 hours
- D 7 days
Correct answer: B. 72 hours
Explanation
Forensic entomology uses the developmental stage of the oldest insect present to set a minimum PMI. If third-instar larvae require 72–96 hours to develop from egg, then the corpse must have been exposed for at least 72 hours (minimum of the developmental range) to permit that larval stage. PMI equals the accumulated degree-hours or minimum time needed to reach the observed developmental stage. The minimum is 72 hours; actual PMI could be longer if oviposition was delayed.
Reference: The Essentials of Forensic Medicine and Toxicology (Narayan Reddy), 34th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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