Qualitative Analyses of Textile Damage (Cuts and Tears) Applied to Fabrics Exposed to the Decomposition of Carcasses and Associated Insect Activity in an Austral Summer.

Fatal stabbings are the leading cause of homicide in countries with restricted access to firearms, such as Australia. The analysis of damage on clothing imparted by a sharp object can assist in the characterization of the weapon. However, decomposition and carrion insects can modify the features of the damage, impeding textile damage analysis and crime reconstruction. This study aimed to identify and characterize the modifications of textile damage over 47 days of decomposition during the summer season in Western Australia. Fabric modifications were analyzed on cotton, synthetic, and blended fabrics with standardized cuts and tears, wrapped on 99 stillborn piglets. Six unclothed piglets acted as controls, with three being stabbed. All piglets were placed simultaneously in the field alongside swatches of fabric. Analyses considered taphonomy, insect interactions, and any textile damage using optical microscopy and SEM. The results showed that carrion insects can modify existing cuts and tears and introduce new artifacts on textiles. The 100% cotton fabric was the most affected by mechanical and chemical degradation, especially cuts and areas stained with blood or decomposition fluids. The study highlights the combined effect of multiple factors on textile damage, including the type of fabric, initial damage, bloating, insect activity, and biodegradation.

A Summary of Concepts, Procedures and Techniques Used by Forensic Entomologists and Proxies.

Forensic entomology is a branch of forensic science that incorporates insects as a part of solving crime. Insect-based evidence recovered at a crime scene can be used to estimate the minimum postmortem interval, determine if a carcass/corpse has been relocated, and contribute to the cause and manner of death. The current review summarises the stepwise usage of forensic entomology methods at a crime scene and in the laboratory, including specimen collection and rearing, identification, xenobiotic detection, documentation, and referencing previous research and casework. It also provides three standards for the collection of insects when attending a crime scene. The Gold standard attributes to a forensic entomologist (FE) who is likely to be well-trained attending a scene. The subsequent standards (Silver and Bronze) have been added because the authors believe that this information is currently missing in the literature. The purpose is so that an attending crime scene agent/proxy with some basic knowledge and some simple tools can recover almost all the insect information required by an FE to make the best estimation of the minimum postmortem interval.

Chasing Flies: The Use of Wingbeat Frequency as a Communication Cue in Calyptrate Flies (Diptera: Calyptratae).

The incidental sound produced by the oscillation of insect wings during flight provides an opportunity for species identification. Calyptrate flies include some of the fastest and most agile flying insects, capable of rapid changes in direction and the fast pursuit of conspecifics. This flight pattern makes the continuous and close recording of their wingbeat frequency difficult and limited to confined specimens. Advances in sound editor and analysis software, however, have made it possible to isolate low amplitude sounds using noise reduction and pitch detection algorithms. To explore differences in wingbeat frequency between genera and sex, 40 specimens of three-day old Sarcophaga crassipalpis, Lucilia sericata, Calliphora dubia, and Musca vetustissima were individually recorded in free flight in a temperature-controlled room. Results showed significant differences in wingbeat frequency between the four species and intersexual differences for each species. Discriminant analysis classifying the three carrion flies resulted in 77.5% classified correctly overall, with the correct classification of 82.5% of S. crassipalpis, 60% of C. dubia, and 90% of L. sericata, when both mean wingbeat frequency and sex were included. Intersexual differences were further demonstrated by male flies showing significantly higher variability than females in three of the species. These observed intergeneric and intersexual differences in wingbeat frequency start the discussion on the use of the metric as a communication signal by this taxon. The success of the methodology demonstrated differences at the genus level and encourages the recording of additional species and the use of wingbeat frequency as an identification tool for these flies.

Domestic Filth Flies in New Haven, Connecticut: A Case Study on the Effects of Urbanization and Climate Change by Comparing Fly Populations after 78 Years.

Changes in common and widespread insect populations such as the domestic filth fly in urban cities are useful and relevant bioindicators for overall changes in the insect biomass. The current study surveyed necrophagous flies by placing a weekly trap from June-September over a two-year period in the city of New Haven, Connecticut, to compare data on fly abundance and diversity with data collected 78 years earlier. Climate and land cover changes were also assessed in combination with the fly population for each period. The survey results suggest the domestic filth fly population is now less diverse with decreased species richness and changes in the relative abundance of species. In both surveys, 95-96% of the population was composed of only three species. The current survey data indicate the numerical dominance of Lucilia sericata has decreased, the abundance of several species, notably Lucilia coeruleiviridis, has increased, and Lucilia illustris is absent. Species that showed a significant interaction with temperature in the 1940s survey have now increased in abundance, with several of the trapped species continuing to show an interaction with temperature and rainfall. Analysis of the land cover and climate data characterizes the trap site as a region exposed to a prolonged period of industrialization and urbanization, with only 7% of the land cover remaining undeveloped and over 50% impervious, coupled with an increase in temperature and rainfall. This study serves as a model for changes in domestic filth fly populations and other insects in similarly highly urbanized established cities.

The effect of submersion in different types of water on the survival and eclosion of blow-fly intra-puparial forms (Diptera: Calliphoridae).

Blow-fly (Diptera: Calliphoridae) immatures are the main colonizers of decomposing remains, and any information on what influences their growth and development are important to forensic entomologists when they are required to estimate post-mortem intervals during a death investigation. Much of this work has been qualified and quantified in terrestrial environments, but is deplete in aquatic environments. When considering a blow-fly's life history, the longest immature life stage goes from the formation of the puparium to adult emergence, and involves metamorphosis. In an aquatic scenario a corpse may be completely submerged, floating on the surface and or it could be associated with water but neither submerged or floating (e.g. beached on a seashore or washed up after a flood event). The present study concerns two blow-fly species, Lucilia sericata (Meigen) and Calliphora vomitoria (L.), and the effects of the age of the intra-puparial forms ("pupal age") and resultant survival, when submerged in tap, river or salt water for varying times - up to 3 days. The experiment was conducted in two localities, L. sericata in Boston USA and C. vomitoria in Turin, Italy, and full puparia of both species were divided into 4 age cohorts ("white", "young", "medium", and "old') before submergence. L. sericata intra-puparial forms showed a three time greater survival rate compared to C. vomitoria intra-puparial forms when submerged in each of the three water types. Both species had the highest survival rate in tap water. Overall, younger and older intra-puparial forms showed a greater and significant survival rate than medium intra-puparial forms when submerged. The eclosion time following submersion of C. vomitoria and L. sericata was mainly influenced by both the age at which the intra-puparial forms were submerged, and by the type of water, but the duration of the submersion also influenced the eclosion time of L. sericata. These results are discussed considering blow-fly physiology. A deeper understanding of the dynamics of survival and growth rate of blow-fly intra-puparial forms on human remains that have undergone a period of submergence could assist in the estimation of the time of death in criminal cases connected to different aquatic environments.

Barnacle colonization of shoes: Evaluation of a novel approach to estimate the time spent in water of human remains.

Estimating the time since death (minimum Post Mortem Interval, minPMI) is a necessary part of a forensic investigation. Besides considering the typical signs of death, minPMI can be estimated using the insects and other arthropods that colonize the remains (forensic entomology). In an aquatic environment, both insects and crustaceans may provide information regarding the time spent in water of the remains (minimum Floating Interval, minFI and minimum Post Mortem Submersion Interval, minPMSI), and this can also assist in determining the minPMI. Barnacles (Crustacea: Cirripedia) are common crustaceans that colonize solid substrates in marine environments and they can be found in association with organic and inorganic remains recovered from the sea. Barnacles colonize both floating and submerged remains and their growth rate is temperature dependent. Despite their potential to be indicative of the minFI and/or minPMSI, only a few case studies have considered it for this purpose, and scant research has been conducted in this field. Assuming that the vast majority of the bodies found in the sea are clothed, this research is focused on the barnacle colonization of two different types of shoes placed in the sea, in order to (1) identify the colonizing species in the chosen environment; (2) identify the settlement preferences of the barnacles associated with the shoes; and (3) determine the factors affecting the growth rate of the barnacles associated with the shoes. In April 2016 64 sport shoes (SS) and 64 patent leather shoes (PLS) were placed in the Boston Harbor (MA-USA) at 8/10m below sea level. Four of each shoe type were collected every two weeks for seven months. Individual barnacles from each shoe were sampled and measured to determine species and age. The overall colonization density and settlement preference was statistically analyzed. Results show that (a) Amphibalanus improvisus (Darwin) (Crustacea: Cirripedia: Sessilia) colonized the vast majority of shoes; (b) colonization occurred in less than 30 days and continued throughout the research period; (c) a significant difference in colonization densities was found between the SS and PLS, with PLS seeing higher densities; (d) barnacles showed preferential colonization of specific sections on both shoe types; (e) barnacle growth was found to be significantly affected by water temperature and shoe type but not by the time spent in water; (f) time spent in water and shoe type had a highly significant effect on the total number of barnacles per shoe, whereas water temperature did not.

Preliminary investigation of aircraft mounted thermal imaging to locate decomposing remains via the heat produced by larval aggregations.

This study investigated the potential of aircraft mounted thermal imaging (AMTI) to locate surficial decomposing remains (clothed and unclothed) through detection of heat generated by larval aggregations of carrion feeding insects. Two trials were carried out, each utilising four pig cadavers (40-45kg) as human analogues and exposing them to insect activity in autumn and winter on the Swan Coastal Plain, Western Australia. The Western Australia Police Air Wing helicopter, fitted with a forward looking infrared radiometer (FLIR) camera, was utilised to obtain the AMTI footage of carcasses over time. The helicopter obtained footage on six occasions during Trial 1 and 22 times during Trial 2. The carcasses were visited daily to record temperature data, insect activity and the state of decay. Activity of blow fly larval aggregations and corresponding heat generation was greatest during the active decay stage; in this period surficial remains were strongly detectable by AMTI at distances of up to one kilometre away. The average ambient daytime temperature during autumn was 27.6±3.4°C and AMTI was most effective 3-8days after death. During winter the average daytime temperature was 14.2±2.6°C and AMTI was most effective 10-23days after death. As the timing of larval aggregation activity varied significantly in different seasons, climatic conditions must be considered when assessing the window of opportunity for AMTI as a viable search technique. Despite climatic variation, the temperature difference between larval aggregations and surrounding soil was remarkably consistent across both seasons (8.9±1.0°C). AMTI was determined to be most effective between 9 pm and 5 am. A predictive tool for determining the window of opportunity for the successful detection of larval aggregations under Western Australian environmental conditions is provided.

Development and validation of an HPLC-MS/MS method for the detection of ketamine in Calliphora vomitoria (L.) (Diptera: Calliphoridae).

Entomotoxicology is a branch of forensic entomology that studies the detection of drugs or other toxic substances from insects developing on the decomposing tissues of a human corpse or animal carcass. Entomotoxicology also investigates the effects of these substances on insect development, survival and morphology to provide an estimation of the minimum time since death. Ketamine is a medication mainly used for starting and maintaining anesthesia. In recent years ketamine has also been used as a recreational drug, and occasionally as a sedating drug to facilitate sexual assault. In both activities, it has resulted in several deaths. Furthermore, ketamine has been also implicated in suspicious deaths of animals. The present research describes for the first time the development and validation of an analytical method suited to detect ketamine in larvae, pupae, empty puparia, and adults of Calliphora vomitoria L. (Diptera: Calliphoridae), using liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). This research also considers the effects of ketamine on the survival, developmental rate and morphology (length and width of larvae and pupae) of C. vomitoria. The larvae were reared on liver substrates homogeneously spiked with ketamine concentrations consistent with those found in humans after recreational use (300 ng/mg) or allegedly indicated as capable of causing death in either humans or animals (600 ng/mg). The results demonstrated that (a) HPLC-MS/MS method is applicable to ketamine detection in C. vomitoria immatures, not adults; (b) the presence of ketamine at either concentration in the food substrate significantly delays the developmental time to pupal and adult instar; (d) the survival of C. vomitoria is negatively affected by the presence of ketamine in the substrate; (e) the length and width of larvae and pupae exposed to either ketamine concentration were significantly larger than the control samples.

The effect of antifreeze (ethylene glycol) on the survival and the life cycle of two species of necrophagous blowflies (Diptera: Calliphoridae).

Entomotoxicology involves the analysis of the presence and the effects of toxicological substances in necrophagous insects. Results obtained by entomotoxicological studies may assist in the investigation of both the causes and the time of death of humans and animals. Ethylene glycol (EG) is easy to purchase, sweet and extremely toxic. It may be consumed accidentally or purposefully, in an attempt to cause death for suicidal or homicidal intent. Several cases report fatalities of humans and animals. The present study is the first to examine the effects of EG on the survival, developmental rate and morphology of two blowfly species, (Diptera: Calliphoridae) typically found on corpses and carcasses: Lucilia sericata (Meigen) and L. cuprina (Wiedemann). Both species were reared on substrates (beef liver) spiked with three different concentrations of EG that could cause death in either a human or cat: 1/2LD50 (T1), LD50 (T2), 2LD50 (T3), in addition to a control treatment (C) with no EG. Results of this research show that: a) both species are unable to survive if reared on a food substrate spiked with the highest concentration of EG (T3), while lower and medium concentrations (T1, T2) affect, but not prevent, the survival and the completion of the life cycle of such species; b) adults of L. sericata eclose only in C and T1, while adults of L. cuprina in both C, T1, T2; however, c) the developmental time of both species reared in T1 and T2 is statistically slower than the control; d) the body length of the immatures of both of the species reared in T1 and T2 is statistically smaller than the control.

Development and Validation of a Method for the Detection of α- and ß-Endosulfan (Organochlorine Insecticide) in Calliphora vomitoria (Diptera: Calliphoridae).

Entomotoxicology studies employ analytical methods and instrumentation to detect chemical substances in carrion insects feeding from the decomposing tissues. The identification of such chemicals may determine the cause of death and may be used for the estimation of the minimum time since death. To date, the main focus of entomotoxicological studies has been the detection of drugs, whereas little information concerns the effects of pesticides on blowflies. Pesticides are generally freely available and more affordable than drugs but they can also be a home hazard and an accessible candidate poison at a crime scene. A QuEChERS extraction method followed by Gas chromatography-mass spectrometry (GC-MS) analysis was developed for the detection of α- and ß-endosulfan (organochlorine insecticide and acaricide) in Calliphora vomitoria L. (Diptera: Calliphoridae) and validated. Furthermore, the effects of endosulfan on the morphology, development time and survival of the immature blowflies were investigated. Larvae were reared on liver substrates homogeneously spiked with aliquots of endosulfan corresponding to the concentrations found in body tissues of humans and animals involved in endosulfan poisoning. Results demonstrated that the combination of QuEChERS extraction and GC-MS provide an adequate methods to detect both α- and ß-endosulfan in blowfly immatures. Furthermore, the presence of α- and ß-endosulfan in the food source 1) prevented C. vomitoria immatures reaching the pupal instar and, therefore, the adult instar at high concentrations, 2) did not affect the developmental time of blowflies at low concentrations 3) affected the size of immatures only at high concentrations, resulting in significantly smaller larvae.

A comparison of carcass decomposition and associated insect succession onto burnt and unburnt pig carcasses.

The rate of decomposition and insect succession onto decomposing pig carcasses were investigated following burning of carcasses. Ten pig carcasses (40-45 kg) were exposed to insect activity during autumn (March-April) in Western Australia. Five replicates were burnt to a degree described by the Crow-Glassman Scale (CGS) level #2, while five carcasses were left unburnt as controls. Burning carcasses greatly accelerated decomposition in contrast to unburnt carcasses. Physical modifications following burning such as skin discolouration, splitting of abdominal tissue and leathery consolidation of skin eliminated evidence of bloat and altered microambient temperatures associated with carcasses throughout decomposition. Insect species identified on carcasses were consistent between treatment groups; however, a statistically significant difference in insect succession onto remains was evident between treatments (PERMANOVA F (1, 224) = 14.23, p < 0.01) during an 8-day period that corresponds with the wet stage of decomposition. Differences were noted in the arrival time of late colonisers (Coleoptera) and the development of colonising insects between treatment groups. Differences in the duration of decomposition stages and insect assemblages indicate that burning has an effect on both rate of decomposition and insect succession. The findings presented here provide baseline data for entomological casework involving burnt remains criminal investigations.

Effect of Continuous and Cyclic Exposure to a Cold Environment on the Development of Larvae of Lucilia sericata (Diptera: Calliphoridae) in Different Sized Larval Masses.

Regulation of forensic practice in many countries prevents the pathologist performing an immediate autopsy. During the period prior to autopsy, the corpse and the insects possibly associated with it are stored in a mortuary with temperatures ∼4°C. When a corpse is found in a late stage of decay, fly immatures may be present as small or large larval masses. The purpose of refrigeration at 4°C is to slow down the decomposition of the corpse as well as the temporary disruption of the activity and development of the bacteria and the necrophagous insects associated with the corpse. The aim of this research is to investigate the growth and development of different larval masses of the blowfly Lucilia sericata (Meigen) (Diptera: Calliphoridae) when stored in a cold environment (4°C). The research was divided into experimental sessions comprising different storage conditions (continuous or cyclic exposure to a cold environment) for immature stages (second and third instar) and included four different sizes of larval mass (∼100, 500, 1,000, and 5,000 larvae) feeding on 4 kg of beef liver and replicated three times. Results show that if the larval mass has a size of ∼5,000 larvae, and the larvae have already reached third instar, then when they are exposed to a cold environment, their development continues. The storage condition at 4°C does not disrupt the development of such larvae. The number of larvae and their instar that make up the larval mass are essential data for the subsequent estimation of a correct minimum postmortem interval.

Development and validation of a GC-MS method for nicotine detection in Calliphora vomitoria (L.) (Diptera: Calliphoridae).

Entomotoxicology is the application of toxicological methods and analytical procedures on necrophagous insects feeding on decomposing tissues to detect drugs and other chemical components, and their mechanisms affecting insect development and morphology and modifying the methodology for estimation of minimum time since death. Nicotine is a readily available potent poison. Because of its criminal use, a gas chromatography-mass spectrometry (GC-MS) method for the detection of nicotine in Calliphora vomitoria L. (Diptera: Calliphoridae) was developed and validated. Furthermore, the effect of nicotine on the development, growth rate, and survival of this blowfly was studied. Larvae were reared on liver substrates homogeneously spiked with measured amounts of nicotine (2, 4, and 6 ng/mg) based on concentrations that are lethal to humans. The results demonstrated that (a) the GC-MS method can detect both nicotine and its metabolite cotinine in immature C. vomitoria; (b) the presence of nicotine in the aforementioned three concentrations in food substrates did not modify the developmental time of C. vomitoria; (c) during the pupation period, larvae exposed to nicotine died depending on the concentration of nicotine in the substrate; and (d) the resultant lengths of larvae and pupae exposed to 4 and 6 ng/mg concentrations of nicotine were significantly shorter than those of the control.

A Biological and Procedural Review of Forensically Significant Dermestes Species (Coleoptera: Dermestidae).

The analyses of the insect species found on decomposing remains may provide useful information for the estimation of the minimum time elapsed since death and other parameters, such as causes and circumstances of death. The majority of research has focused on the early colonizing species, typically blowflies, while research concerning late colonizing insects is currently sparse. Dermestid beetles of the genus Dermestes L. (Coleoptera: Dermestidae) are one of the predominant insect species associated with decomposing remains during dry decay and skeletal stages of decomposition. In some dry environments, Dermestes species are likely to be the only necrophagous insects feeding on the decomposing remains. Furthermore, Dermestes species (immature and adults), their remains (cast skins and fecal material), and their artifacts (pupal chambers) are frequently found associated with ancient remains (e.g., mummies, fossils). Dermestes species have a worldwide distribution and are considered important in decomposition processes, forensic investigations, and economically as a known pest of stored products. Despite their recognized forensic importance, there is limited data documenting the ecology, biology, and the growth rates of the forensically relevant species. The aim of this review is to provide a comprehensive synopsis on the available literature concerning Dermestes species associated with forensic cases. In particular, aspects of colonization behavior, growth rates for forensic taxa and potential best practice guidelines for forensic casework encompassing late colonizing Dermestes species are discussed.

Evaluation of the floating time of a corpse found in a marine environment using the barnacle Lepas anatifera L. (Crustacea: Cirripedia: Pedunculata).

Human activities involving water may result in a crime scene. Typically, death may be due to natural causes, homicide, or mass disasters. Decomposition in water is a complex process where many factors may interplay. Human remains in water are subject to many potential interactions, depending upon the remains themselves, the type of water and the characteristics of the water. A number of studies are focused on the decomposition process of the corpse in water, on the identification of the post mortem submersion interval (PMSI) and on the diagnosis of drowning, but very few studies consider the fate of floating remains in any aquatic environment. The following case describes a corpse found on a shore of the Tyrrhenian Sea (South West of Italy, Calabria Region). The corpse and the soles of his shoes were colonized by the barnacle Lepas anatifera L. (Crustacea: Cirripedia: Pedunculata). The analyses of the barnacles present on the corpse aided in the evaluation of the floating time of the corpse which assisted in estimating the minimum time since death.

Development of a GC-MS method for methamphetamine detection in Calliphora vomitoria L. (Diptera: Calliphoridae).

Entomotoxicology is the study of using insects for the detection of drugs and other chemical substances in decomposing tissues. One research aspect in particular is the effects of these substances on arthropod development and morphology, and their consequences on the post mortem interval estimation. Since methamphetamine (MA) is becoming commonplace as an illegal recreational drug, a GC-MS method for the detection of MA in Calliphora vomitoria L. (Diptera: Calliphoridae) was developed and validated. Furthermore, the effect of MA on the development, growth rates and survival of the blowfly was investigated. Larvae were reared on liver substrates homogeneously spiked with measured amounts of MA (5 ng/g and 10 ng/g) based on typical concentrations found in human tissue in cases of death caused by MA overdose. The experimental results demonstrated that (i) MA produced a significant increase in the developmental time from egg to adult in C. vomitoria, (ii) approximately 60% of larvae exposed to either dose of MA died during the pupation period and (iii) the resultant lengths of larvae and pupae were on average significantly larger than the controls.

Survival and development of the forensically important blow fly, Calliphora varifrons (Diptera: Calliphoridae) at constant temperatures.

The influence of temperature on the development of the forensically important blow fly, Calliphora varifrons Malloch 1932 (Diptera: Calliphoridae), was investigated at seven constant temperatures ranging from 12 to 30 °C. C. varifrons completed development between 12 and 27 °C. At 30 °C larvae formed pupae but did not successfully emerge. Temperature significantly influenced development time, mortality, maximum larval length, and adult body size. Development time (larviposition to adult emergence) ranged from 16.65 ± 0.17 days at 27 °C to 49.93 ± 0.26 days at 12 °C. Development rate was essentially linear throughout the 12-27 °C temperature range. Linear estimates of lower developmental threshold and thermal requirement (K) for development of C. varifrons were 4.20 °C and 368.46 ± 26.38 K. At 30 °C, a slight inhibitory effect of high temperature on third instar development rate was observed followed by a rapid decline when subsequent development and survival ceased. Nonlinear estimates of lower developmental threshold for third instar development were comparatively higher (6.29 °C). Nonlinear estimates of optimal developmental temperature and upper lethal developmental threshold were 25.94 and 32.13 °C respectively. Mortality was high at both temperature extremes (12 and 27 °C) and lowest between 18 and 24 °C. Maximum larval length was inversely related to temperature. Adult body size was significantly smaller at 12 °C, peaked at 18 °C, and declined as temperatures increased. The species-specific development data presented are the first available for C. varifrons for use by forensic practitioners for estimation of minimum time since death.

Syritta pipiens (Diptera: Syrphidae), a new species associated with human cadavers.

The analyses of necrophagous insects feeding on a corpse can be successfully used to estimate the minimum time since death. A minimum time frame is sometimes an underestimate, but it is actually the only method that can provide such information when decomposed remains are found at a crime scene. Many insects are known to be colonisers of a corpse, but because there is an endless spectrum of crime scene environments, the development data bases for necrophagous insects is incomplete. The two cases detailed in this paper show different entomological patterns due to the different environments (well and burial) and locations (south and central Italy) where the two cadavers were found. Common to both of these cases' was the discovery of the corpse in the same period of the year (January) and the presence of Syritta pipiens (Diptera: Syrphidae), a species that has never been associated with deceased humans. The ecological information concerning this insect was used in combination with the more typical entomofauna found on the corpse to provide a minimum post mortem interval.

Human remains found in two wells: a forensic entomology perspective.

When estimating the time since death or manner of death, the identification and the pathological evaluations of a body are generally impeded by post mortem changes. Research and case studies help experts to achieve a more accurate diagnosis, but at present there is scant literature covering topics concerning forensic science and decompositional processes in aquatic environments. The two case studies presented each involve a decomposed body found in a unique aquatic environment; namely wells containing ground water. In Case 1 an entomologist attended the scene and in Case 2 an entomologist was only involved after 20 months when it was decided that the insect evidence collected at the second autopsy may be useful in determining a time frame. The first case highlights the problems associated with body retrieval from aquatic environments as the body was removed it dismembered. Fortunately, the well was able to be drained, so much of the insect evidence was retrieved. In the second case the body was found dismembered but the entomological evidence was overlooked and lost. During the second autopsy insects were found, collected, and sent to an entomologist to help clarify the post mortem interval.

Entomological evidence: lessons to be learnt from a cold case review.

Insects are known to be useful in estimating time since death, but this is only possible if samples are collected and preserved correctly according to best practices. This report describes a case where an 18-year old female was found dead and during the first medico-legal investigation which determined it was a homicide, entomological samples were collected but not considered. The case was then closed with no suspect. However, 9 years after the first investigation the courts decided that the case needed to be re-examined. In doing so the new review team decided that although the remaining entomological evidence was poorly preserved some extra information may be gained from its analyses. On inspection of the remaining samples of larvae no normal morphological analyses could be conducted. Molecular analyses were combined with an unorthodox morphological analysis to provide an estimate of the post-mortem interval based on insect evidence, indicating the value of multidisciplinary approaches to both cold and contemporary cases.