Establishing the post mortem interval (PMI) is a key component of every medicolegal death investigation. Several methods based on different approaches have been suggested to perform this estimation. Among them, two methods based their evaluation on the effect of the temperature and time on the considered parameters: total body score (TBS)/accumulated degree-days (ADDs) and insect development. In this work, the two methods were compared using the results of minPMI and PMI estimates of 30 forensic cases occurring in northern Italy. Species in the family Calliphoridae (Lucilia sericata, Calliphora vomitoria and Chrysomya albiceps) were considered in the analyses. The results highlighted the limits of the TBS/ADD method and the importance of the entomological approach, keeping in mind that the minPMI is evaluated. Due to the fact that the majority of the cases occurred in indoor conditions, further research must also be conducted on the different taxa to verify the possibility of increasing the accuracy of the minPIM estimation based on the entomological approach.
Diptera identification is fundamental in forensic entomology as well as in funerary archeoentomology, where the challenge is exacerbated by the presence of immature stages such as larvae and puparia. In these two developmental stages, specimens possess a very limited number of diagnostic features, and for puparia, there is also a lack of identification tools such as descriptions and identification keys. Morphological analysis, DNA-based techniques, and cuticular chemical analyses all show good potential for species identification; however, they also have some limitations. DNA-based identification is primarily hindered by the incompleteness of genetic databases and the presence of PCR inhibitors often co-extracted from the puparial cuticle. Chemical analysis of the cuticle is showing promising results, but this approach is also limited by the insufficient profile database and requires specific, expensive equipment, as well as trained personnel. Additionally, to ensure the repeatability of the analysis—a critical aspect in forensic investigations—and to preserve precious and unique specimens from museum collections, non-invasive protocols and techniques must be prioritized for species identification.
1 April 2019 in Journal of Archaeological Science: Reports
Diptera puparia may represent both in forensic and archaeo-funerary contexts the majority of the entomological evidence useful to reconstruct the peri and post-mortem events. Puparia identification is quite difficult due to the lack of identification keys and descriptions. In addition, external substances accumulated during the puparia permanence in the environment make the visualization of the few diagnostic characters difficult, resulting in a wrong identification. Six different techniques based on physical and chemical treatments have been tested for the removal of external substances from puparia to make identification at species level feasible. Furthermore, the effects of these methods on successful molecular analyses have also been tested as molecular identification is becoming an important tool to complement morphological identifications. The results of this study indicate that cleaning via warm water/soap, the sonication and treatment with a sodium hydroxide solution are the best methods to achieve a good quality of the samples.
4 January 2023 in Medical and Veterinary Entomology
During renovations within the crypt of the Sant’Antonio Abate Cathedral in Castelsardo (Sardinia, Italy), an ossuary and several mummies were discovered. Entomological remains were collected in two different surveys: one performed by archaeologists in 2011 and a second one conducted by an entomologist in 2018. In 2018, Giordani and colleagues published a paper presenting the results of the entomo-fauna analysis of samples collected during the first survey. The present paper presents the results of the second survey. Thousands of specimens have been newly collected and analyzed, including insects belonging to Coleoptera, Lepidoptera, Hymenoptera, Siphonaptera and Diptera, as well as arthropods belonging to Arachnida and Malacostraca. The results here presented confirm the Giordani’s conclusion but also provide new information about the presence of potential vectors of diseases in the Castelsardo population in the end of the 18th—beginning nineteenth century.