Forensic Importance of Aquatic Arthropods and Molecular Biomarkers in Criminal Investigations on Floating Cadavers: A Narrative Review

In an aquatic environment, determining the cause and manner of death for bodies recovered from water can be quite challenging. Postmortem modifications add another layer of complexity to this process. First, it must be established that the recovery site is the primary death scene; for example, a death may occur on land, with the body subsequently disposed of by being submerged in water, and vice versa. Therefore, understanding how environmental conditions and variables affect the distribution of arthropods, including insects, on carcasses is essential for estimating the time interval after death. However, research and references focusing on the relationship between arthropods and corpses from a forensic perspective are sparse and often disconnected, particularly regarding the aquatic environment and aquatic arthropods. These organisms play a significant role in corpse analysis and detection during investigations, especially in criminal cases involving the flotation of bodies infested with fly larvae. The presence of these larvae is influenced by the aquatic environment, which is affected by various factors such as water type, chemicals present, physical characteristics, microbes in the surrounding water, and seasonal variations at the time of death. While many larvae have been identified at different developmental stages, their overall quantity tends to be lower compared to those typically found on terrestrial carcasses. Nonetheless, the presence of aquatic insects on corpses can serve as a valuable indicator of the location of death in relation to the aquatic environment. Thus, arthropod analysis is an important tool in investigations involving cadavers discovered in aquatic settings.