Mitochondrial DNA-Based Identification of Forensically Important Flesh Flies (Diptera: Sarcophagidae) in Thailand

摘要

Flesh flies (Sarcophagidae) are necrophagous insects initially colonizing on a corpse. The species-specific developmental data of the flies collected from a death scene can be used to estimate the minimum postmortem interval (PMI ). Thus, the first crucial step is to correctly identify the fly species. Because of the high similarity among species of flesh flies, DNA-based identification is considered more favorable than morphology-based identification. In this study, we demonstrated the effectiveness of combined sequences (2216 to 2218 bp) of cytochrome c oxidase subunit I and II genes ( and ) for identification of the following 14 forensically important flesh fly species in Thailand: Lopes, (Senior-White), (Senior-White), (Fabricius), (Senior-White), (Pape & Bänziger), (Meigen), (Ho), (Thomson), (Walker), (Böttcher), (Walker), (Ho) and (Wiedemann). Nucleotide variations of Thai flesh flies were evenly distributed throughout the genes. Mean intra- and interspecific variations ranged from 0.00 to 0.96% and 5.22% to 12.31%, respectively. Using Best Match (BM) and Best Close Match (BCM) criteria, identification success for the combined genes was 100%, while the All Species Barcodes (ASB) criterion showed 76.74% success. Maximum Likelihood (ML) and Bayesian Inference (BI) phylogenetic analyses yielded similar tree topologies of monophyletic clades between species with very strong support values. The achieved sequences covering 14 forensically important flesh fly species including newly submitted sequences for . , . and . , can serve as a reliable reference database for further forensic entomological research in Thailand and in other areas where those species occur.