Review of some recent techniques of age determination of blow flies having forensic implications

Forensic entomology can aid death investigation by using predictable developmental changes to estimate the age of flies associated with a body. Forensic entomologists use size and developmental stages to estimate blowfly age, and from those, a Postmortem Interval. Calliphorids are very interesting in forensic sciences from an applied point of view, because they provide relevant evidence for estimating the Postmortem Interval. Since such estimates are generally accurate but often lack precision, particularly in the older developmental stages, so there is a need of some alternative aging methods. The range of techniques available for age grading of adult insects is reviewed, with particular emphasis on species of medical importance. The techniques described include pteridine fluorescence analysis, internal morphological analysis, cuticular hydrocarbon analysis, gene expression analysis, cuticular banding pattern analysis, volatile organic compounds analysis released by larvae and pupae.