Description of the puparium and other notes on the morphological and molecular identification of Phthitia empirica (Diptera, Sphaeroceridae) collected from animal carcasses

G Giordani,S Vanin

doi:10.1186/s41935-020-00187-2

Abstract

BackgroundA correct identification of species is fundamental in order to derive all the biological, ecological, and behavioral information useful to reconstruct previous events when insects are used in forensic and funerary archaeological contexts. Little attention was paid in the past to the description of the immature stages of flies, especially of species belonging to family found only occasionally on human cadavers and animal carrion. Sphaeroceridae species belong to this category.ResultsIn this work, adult and puparia of Phthitia empirica (Hutton, 1901) are illustrated and described. In addition, some observations about the molecular identification of this species are presented and discussed.ConclusionsThis work will allow the identification of puparia of this species providing additional tools in forensic entomological investigation. More in general, the effort of producing morphological descriptions and molecular information of species of potential forensic interest clearly implements the possibility to provide a deeper understanding of the peri- and post-mortem events in violent crimes.

Highlights

A correct identification of species is fundamental in order to derive all the biological, ecological, and behavioral information useful to reconstruct previous events when insects are used in forensic and funerary archaeological contexts
During a study on the necro-microbiome characterizing the decomposition of animals (Tuccia et al 2019), some specimens of Phthitia empirica (Hutton, 1901) (Diptera, Sphaeroceridae) were collected from rabbit carcasses over 2 years after the carcasses’ exposure
The difficulties in puparia morphological identification is due to the paucity of specific identification keys for this developmental stage and to the fact that often some diagnostic characters of larvae are not visible or are deformed in the puparium (Giordani et al 2018a)

Summary

Introduction

A correct identification of species is fundamental in order to derive all the biological, ecological, and behavioral information useful to reconstruct previous events when insects are used in forensic and funerary archaeological contexts. Little attention was paid in the past to the description of the immature stages of flies, especially of species belonging to family found only occasionally on human cadavers and animal carrion. Giordani and Vanin Egyptian Journal of Forensic Sciences (2020) 10:13 important problems to be solved, especially when immature stages are found. This problem is still relevant and sometimes impossible to solve when empty puparia are found and no molecular analysis can be performed on them because of the low amount of DNA, or the DNA degradation and the presence of PCR inhibitors (Scholz et al 1998; Kemp et al 2006). The problem of puparia identification is worst in taxa only occasionally reported from cadavers and carcasses (Giordani et al 2018b) where often the larvae are not described

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Discussion

Conclusion