Cytochrome b as a useful tool for the identification of blowflies of forensic interest (Diptera, Calliphoridae)

In Forensic Entomology the fast and accurate identification of insects collected at the scene of events is essential if errors are to be avoided in estimating infestation times of interest and determining the post-mortem interval (PMI). Traditional identification based on morphological characteristics can be complicated due to physical similarities between different species, especially at immature stages. Genetic analysis provides a fast and reliable identification method. In this paper, molecular analysis is focused on a fragment of 307 bp of the mitochondrial DNA region that codes for cytochrome b (cyt b). Six species belonging three genera of Calliphoridae of forensic interest (Calliphora vicina, Calliphora vomitoria, Lucilia sericata, Lucilia caesar, Lucilia ampullacea, Chrysomya albiceps) were collected and identified. These are the most common species of cadaveric entomofauna on the Atlantic seaboard of the Iberian Peninsula. The results show the robustness of the cyt b locus as a diagnostic tool, since its nucleotide variability enables reliable distinctions to be drawn between species. This study also contributes new consense sequences which may be of interest for correct species identification.