Forensic identification of Chrysomya megacephala from a hanging cadaver using mitochondrial COI gene sequencing

Accurate identification of cadaver-associated insects is a critical component of forensic entomology, particularly for reliable estimation of the post-mortem interval (PMI). In the present study, molecular identification of an insect specimen collected from a hanging human body (F1-Hanging) was carried out using mitochondrial cytochrome oxidase I (COI) gene-based DNA barcoding. Genomic DNA extracted from the sample showed a sufficient concentration (116 ng/µl) and high quality, enabling successful PCR amplification and sequencing of the COI region. The amplified COI sequence (653 bp) exhibited 98.93% similarity with Chrysomya megacephala reference sequences in the NCBI database based on BLAST analysis. Phylogenetic reconstruction using the Neighbor-Joining method and Jukes-Cantor distance model further confirmed the clustering of the F1-Hanging sample within a well-supported C. megacephala clade. The concordant results obtained from sequence alignment, BLAST analysis, and phylogenetic clustering validate the reliability of COI-based molecular identification. The findings highlight the effectiveness of DNA barcoding as a complementary tool to traditional morphological methods, particularly in forensic cases where specimens may be damaged, immature, or morphologically ambiguous, thereby strengthening the application of molecular approaches in forensic entomology.