ABSTRACT

The rst crucial step a forensic entomologist has to undertake when presented with a crime scene is to identify the insects present. Closely related arthropods that colonize vertebrate carrion can have substantially different development rates, and a misidentication can lead to inaccurate minimum postmortem interval (min-PMI) estimations. The current method used for their identication is dichotomous keys, which are based on morphological features within different insect species. Using these keys require analysts to be very familiar with the anatomical characteristics of the insects examined. However, most identication keys are for adult, and not immature (e.g., egg, larva, pupa) ies. In investigations where immatures are collected, the investigator is asked to rear them to the adult stage. This process can be time consuming and is not guaranteed to result in adults. One way to compliment current identication methods is DNA-based analyses (Sperling et al. 1994). These techniques have been applied in the eld of forensic entomology for over two decades. Sperling et al. (1994) were the rst to test the concept in forensic entomology and much more has been done since then. For examples, refer to the following: Malgorn and Coquoz 1999, Vincent et al. 2000, Stevens and Wall 2001, Wallman and Donnellan 2001, Wells and Sperling 2001, Harvey et al. 2003, Ratcliffe et al. 2003, Schroeder et al. 2003, Ames et al. 2006a, Cainé et al. 2009, Oliveira et al. 2011). DNA is a sound tool for identifying immature blow ies (Diptera: Calliphoridae), as well as showing great potential for ageing some of the life stages. However, DNA-based techniques have a few disadvantages, which could limit their use in the eld. Most studies are using DNA barcoding to identify species, but the clear difference between the number of intra-and interspecic nucleotide variation can be an artifact of insufcient sampling across taxa (Fremdt et al. 2012). Also, the analyst must be a technical expert, and the process can be time consuming and expensive.