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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 physio

The estimation of the time since death (minimum Post Mortem Interval, minPMI) is an essential aspect of forensic investigations. This is particularly complex when a human body is found submerged, floating or beached in a marine environment. When a cadaver is found in a terrestrial environment the minPMI estimation is generally based on the presence of carrion insects. However, when a cadaver is found in an aquatic environment, a correct crime scene reconstruction is more complex and requires the consideration of the time the remains spent submerged underwater (minimum Post Mortem Submersion Interval, minPMSI) and/or floating (Floating Interval, FI). In marine crime scene scenarios, the use of barnacles (Crustacea: Cirripedia) has recently received some attention, due to their permanent settlement on human remains and their accompanying clothing. Previous research considered barnacle growth on human shoes, but the present research is the first to focus on the colonisation of barnacles on clothing materials (fabrics). Polystyrene floats were covered by either cotton, velvet, satin or neoprene and submerged underwater over a period of six months off the coast of Perth, Western Australia. The aims of this research were 1) the identification of marine species colonising the fabrics, with special attention to barnacles; 2) the identification of which fabric type provides the most desirable environment for colonisation; and 3) the identification of factors that affect the growth rate of the different species. Three species of barnacles, Balanus trigonus Darwin, Amphibalanus reticulatus (Utinomi) and A. variegatus (Darwin), were present in varying numbers and sizes. The colonisation process of the barnacles occurred rapidly, with the first sighting of barnacles observed within the first month on neoprene and control floats. The surface that attracted the largest number of barnacles was neoprene, followed by satin and cotton, while velvet showed an inconsistent colonisation

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 physio

The estimation of the time since death (minimum Post Mortem Interval, minPMI) is an essential aspect of forensic investigations. This is particularly complex when a human body is found submerged, floating or beached in a marine environment. When a cadaver is found in a terrestrial environment the minPMI estimation is generally based on the presence of carrion insects. However, when a cadaver is found in an aquatic environment, a correct crime scene reconstruction is more complex and requires the consideration of the time the remains spent submerged underwater (minimum Post Mortem Submersion Interval, minPMSI) and/or floating (Floating Interval, FI). In marine crime scene scenarios, the use of barnacles (Crustacea: Cirripedia) has recently received some attention, due to their permanent settlement on human remains and their accompanying clothing. Previous research considered barnacle growth on human shoes, but the present research is the first to focus on the colonisation of barnacles on clothing materials (fabrics). Polystyrene floats were covered by either cotton, velvet, satin or neoprene and submerged underwater over a period of six months off the coast of Perth, Western Australia. The aims of this research were 1) the identification of marine species colonising the fabrics, with special attention to barnacles; 2) the identification of which fabric type provides the most desirable environment for colonisation; and 3) the identification of factors that affect the growth rate of the different species. Three species of barnacles, Balanus trigonus Darwin, Amphibalanus reticulatus (Utinomi) and A. variegatus (Darwin), were present in varying numbers and sizes. The colonisation process of the barnacles occurred rapidly, with the first sighting of barnacles observed within the first month on neoprene and control floats. The surface that attracted the largest number of barnacles was neoprene, followed by satin and cotton, while velvet showed an inconsistent colonisation

After death, the body begins decomposition, a process that starts with the breakdown of organic matter and typically leads to the complete degradation of a body. Such a process is highly affected by (micro and macro) environmental factors of intrinsic and extrinsic nature. Adipocere is a substance formed from the decomposition of adipose tissue and represents a disruption to the typical decomposition process. Such disruption causes decomposition to slow or arrest completely, placing a body into a state of preservation, and causes complications in the estimation of the time since death (Post-Mortem Interval, PMI). While several studies have been performed on the nature, the formation and the degradation of adipocere, there is still no reliable model to assess the PMI of a body exhibiting it. Case studies are an important source to aid pathologists and investigators during a case. This review presents a summary and an update on the knowledge surrounding the chemistry and the factors affecting adipocere formation and degradation, the timing and the distribution of adipocere throughout a body, and the techniques used to investigate it. Furthermore, a table of the most important case studies involving adipocere since 1950, several images and descriptions of recent cases and operational considerations for the best practice at the crime scene and autopsy are presented to be used as a reference to facilitate forensic professionals in adipocere cases.

Crime scene investigation protocols and procedures are well established when concerning terrestrial environments, but are limited when associated with aquatic environments. In aquatic contexts, the soil, sediments and microscopic algae (e.g. diatoms) may all be used as sources of trace evidence for criminal investigations. Diatoms are one such source that can be used to support the diagnosis of death by drowning and can be used to verify contact between a suspect and a specific water body. For the latter, diatoms can be collected from clothing and shoes for forensic comparisons. Over the years, there have been several methods proposed for the extraction of diatoms from clothing, however, a best practice method is yet to be established and is still open to debate. The present research represents the first investigation that evaluates four different methods for the extraction of native and common Australian diatom species from four different types of fabrics. Diatoms of two different species and shape (pennate and centric) were cultivated in stimulated experimental waters – prepared using either monocultures or mixed cultures of the selected diatoms. Diatom concentrations were set to mimic the natural population (low to bloom events) as commonly found in the Swan River Estuary of Western Australia. Cotton, denim, blend, and acrylic fabric types were placed in experimental waters. Diatom extraction was attempted using methods already proposed in the literature, these include: rinsing with ethanol (RE); rinsing with ethanol together with the application of centrifugal force (RECF); digestion with hydrogen peroxide (H); and a new method of ashing that has never been tested before (dry ash, DA). Results of this research showed that a) the type and the concentration of the mono and mix diatom mixtures significantly affects the transfer and extraction from different types of fabric; b) a noticeable extraction difference is observed between the fabrics, establishing denim, a

After death, the body begins decomposition, a process that starts with the breakdown of organic matter and typically leads to the complete degradation of a body. Such a process is highly affected by (micro and macro) environmental factors of intrinsic and extrinsic nature. Adipocere is a substance formed from the decomposition of adipose tissue and represents a disruption to the typical decomposition process. Such disruption causes decomposition to slow or arrest completely, placing a body into a state of preservation, and causes complications in the estimation of the time since death (Post-Mortem Interval, PMI). While several studies have been performed on the nature, the formation and the degradation of adipocere, there is still no reliable model to assess the PMI of a body exhibiting it. Case studies are an important source to aid pathologists and investigators during a case. This review presents a summary and an update on the knowledge surrounding the chemistry and the factors affecting adipocere formation and degradation, the timing and the distribution of adipocere throughout a body, and the techniques used to investigate it. Furthermore, a table of the most important case studies involving adipocere since 1950, several images and descriptions of recent cases and operational considerations for the best practice at the crime scene and autopsy are presented to be used as a reference to facilitate forensic professionals in adipocere cases.

Crime scene investigation protocols and procedures are well established when concerning terrestrial environments, but are limited when associated with aquatic environments. In aquatic contexts, the soil, sediments and microscopic algae (e.g. diatoms) may all be used as sources of trace evidence for criminal investigations. Diatoms are one such source that can be used to support the diagnosis of death by drowning and can be used to verify contact between a suspect and a specific water body. For the latter, diatoms can be collected from clothing and shoes for forensic comparisons. Over the years, there have been several methods proposed for the extraction of diatoms from clothing, however, a best practice method is yet to be established and is still open to debate. The present research represents the first investigation that evaluates four different methods for the extraction of native and common Australian diatom species from four different types of fabrics. Diatoms of two different species and shape (pennate and centric) were cultivated in stimulated experimental waters – prepared using either monocultures or mixed cultures of the selected diatoms. Diatom concentrations were set to mimic the natural population (low to bloom events) as commonly found in the Swan River Estuary of Western Australia. Cotton, denim, blend, and acrylic fabric types were placed in experimental waters. Diatom extraction was attempted using methods already proposed in the literature, these include: rinsing with ethanol (RE); rinsing with ethanol together with the application of centrifugal force (RECF); digestion with hydrogen peroxide (H); and a new method of ashing that has never been tested before (dry ash, DA). Results of this research showed that a) the type and the concentration of the mono and mix diatom mixtures significantly affects the transfer and extraction from different types of fabric; b) a noticeable extraction difference is observed between the fabrics, establishing denim, a

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 8/10 meters 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

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 8/10 meters 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

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.

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.

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.

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.