Forensic Importance Research Articles

A short fragment of mitochondrial DNA for the taxonomic identification of blow flies (Diptera: Calliphoridae) in northwestern South America.

Blow flies are of medical, sanitary, veterinary, and forensic importance. Their accurate taxonomic identification is essential for their use in applied research. However, neotropical fauna has not been completely studied or described, and taxa identification without the required training is a difficult task. Additionally, the current morphological keys are not fitting to all extant taxa. Molecular-based approaches are widely used to overcome these issues, including the standard 5' COI barcode fragment (~650 base pairs [bp]) for identification at the species level. Here, a shorter sequence of 5' COI fragment (~342 bp) was assessed for the identification of 28 blow fly species inhabiting the northwest of South America. One tree-based (the generalized mixed Yule-coalescent-GMYC) and 3 distance-based approaches (automatic barcode gap discover - ABGD, the best close match - BCM, and the nearest neighbor - NN) analyses were performed. Noticeably, the amplification and sequencing of samples that had been preserved for up to 57 years were successful. The tree topology assigned 113 sequences to a specific taxon (70% effectiveness), while the distance approach assigned to 95 (59% effectiveness). The short fragment allowed the molecular identification of 19 species (60% of neotropical species except for the Lucilia species and Hemilucilia semidiaphana). According to these findings, the taxonomic and faunistic considerations of the blow fly fauna were provided. Overall, the short fragment approach constitutes an optimal species confirmation tool for the most common blow flies in northwestern South America.

Beetles associated with buried carcasses: potential forensic importance in Riyadh, Saudi Arabia

Burial has a special influence on carrion fauna, which may change the rate of decomposition and so affect postmortem estimates. This study aimed to identify species and succession of beetles on buried remains. From 28 January to 31 May 2021, we examined the Coleoptera on buried and exposed rabbit carcasses, on the campus of the University of King Saud in an area measured around 175 m by 250 m. The area is almost entirely devoid of flora, except for a few acacia trees and some common wild herbs. It is about 1 km away from residential neighborhoods. In total, 165 specimens belonging to 4 families were collected. The Tenebrionidae was the most abundant family, where it formed 52% at a depth of 20 cm and 78% at a depth of 40 cm in the buried carcasses, while the family Dermestidae was the most abundant in the surface carcasses, as it formed 53% of the insects sampled. Type Mesostena puncticollis Solier, 1835 (Tenebrionidae) predominated at exposed carcasses as well as at depths of 20, 40 cm and while type Dermestes frischii Kugelann, 1792 (Dermestidae), predominated at depth of 40 cm and exposed carcasses, and type Saprinus chalcites (Illiger, 1807) (Hisiteridae) at depth of 20 only. These findings are possibly useful in forensic investigations involving buried bodies in Riyadh, Saudi Arabia.

Auricular Anthropometry of Indigenes of Uturu, Abia State, Nigeria

Background: The auricle is an important cephalofacial part of the human body that is of forensic importance that portrays information about one’s age, sex, race and ethnic group.
 Aim: This study was therefore conducted to establish auricular anthropometric data and sexual dimorphic parameters of Uturu indigenes in Southeastern Nigeria.
 Materials and Methods: A total of 370 subjects (185 males and 185 females) of Uturu indigenes who met the inclusion criteria were enrolled in the study. Auricular measurements which include auricular length and width and lobular length and width, as well as lobular attachments were obtained in inches. Data obtained was analyzed using SPSS version 23.0.
 Results: Total mean auricular length, auricular width, lobular length and lobular width in males was 2.11, 1.35, 0.66 and 0.46 respectively while same parameters in females were 2.06, 1.22, 0.66 and 0.44 respectively. No significant sexual dimorphism was observed in the measured parameters except for auricular width (P=0.01). Free earlobe was prevalent (68.92%: n=255) in the study population especially among the female subjects.
 Conclusion: The mean values for all auricular measurements were higher in males than in females except for lobular length which was the same in both sexes. Results The findings from this study provide useful evaluation of the auricular morphological characteristics among the study population will be useful in the documentation of auricular morphometric data, especially within Nigerian population.

Evidence of two mitochondrial lineages and genetic variability in forensically important Lucilia eximia (Diptera: Calliphoridae) in Colombia.

Lucilia eximia (Wiedemann, 1819) (Diptera: Calliphoridae) is a blowfly with medical and forensic importance that shows genetic and color variation, however, these variations have not justified the description of new species. But in forensic entomology an accurate identification of species and subpopulations is crucial. We explored the genetic variation of L. eximia from eight localities, in five natural regions in Colombia using two mitochondrial fragments, including the standard locus for insect identification COI and the Cytb-tRNA-Ser-ND1 region. We found significant differentiation at COI and Cytb-tRNA-Ser-ND1 level, characterizing two lineages and revealing a deep and significant genetic split. High values of FST and genetic distances supported the two lineages. The origin of the divergence of L. eximia remains to discover. Examining whether the lineages have diverse ecological and biological behaviors could be a significant impact on the use of L. eximia in forensic and medical science. Our results could have relevant implications for the use of post-mortem interval estimation based on insect evidence, as well as our sequences improve the database used in DNA-based methods for identifying forensically important flies.

Investigation of the Characteristics of the Milichiidae Family (Arthropoda: Insecta: Diptera)

Most Milichiidae species are very small and dark. Details of their biology have not been properly studied. It is known that the Milichiidae are associated with decomposing plant and animal matter, including animal and human corpses, a reason that has potential importance in their forensic importance; several species are myrmecophilous predators, pollinators and phoretic vectors. This journal aimed to investigate the bioecology, the bionomy, the biography and systematics of the Milichiidae family (Arthropoda: Insecta: Diptera). The research was carried out based on its systematic aspects and family characteristics. The review was inventoried from works published in national and international journals.

Heat-related biomarkers: Focus on the correlation of troponin I and 70 kDa heat shock protein

Heat-related biomarkers: Focus on the correlation of troponin I and 70 kDa heat shock protein Abstract Introduction: There is intensive research related to the forensic importance of biomarkers that would be the standard for postmortem damage to cardiomyocytes and the mechanism of the resulting damage. The aim of the research was to examinate the forensic-medical significance of serum levels of biomarkers as detectors of terminal hyperthermic damage to the myocardium. Material and Method: 40 laboratory animals were divided into groups: the first group was the control (n = 8) exposed to a physiological temperature of 37 °C, the second group was divided into two subgroups: antemortem (n = 8) and postmortem (n = 8), which included a exposure temperature of 41 °C and the third group was divided into two subgroups: antemortem (n = 8) and postmortem (n = 8), which included a exposure temperature of 44 °C. The concentration of cardiac TnI and Hsp70 was resoluted in serum by immunochemical enzyme-labeled immunoabsorption method. Results: A positive correlation was found between the temperature measured at the time of death and the serum values of cTnI (p = 0.02), in G41, and Hsp70 values did not significantly correlate with the core temperature in this group, p > 0.005. A positive correlation was significant between the concentration of Hsp 70 and the body temperature of rats in the group of rats with a fatal outcome was determined, p = 0.03. Conclusion: Changes in the concentration of cTnI and Hsp70 in rat serum may indicate hyperthermic damage to the myocardium in the Wistar rat model of heat stroke.

Flesh Flies (Diptera: Sarcophagidae) of Forensic Importance Collected From Pig Carcasses in the Cerrado of Northeastern Brazil.

Sarcophagidae is a family of true flies frequently found colonizing carcasses and corpses as adults and/or larvae, therefore, they are of great forensic value in the medico-legal field. Thus, this study aims to inventory the sarcophagids species and describe their succession process in the decomposition of swine carcasses in the Cerrado (savanna-like vegetation), Brazilian Northeastern region. A total of 10,819 specimens were collected, belonging to 45 sarcophagid species. Of this total, one species was recently described (Helicobia neuzalmeidae Silva, Brasil, De-Souza & Carvalho-Filho), two [Blaesoxipha (Acanthodotheca) denieri (Blanchard) and Dexosarcophaga pusilla Lopes] are new records for the Cerrado biome, five [Argoravinia (Argoravinia) catiae Carvalho Filho & Esposito, B. (A.) denieri, Nephochaetopteryx orbitalis (Curran & Walley), Peckia (Sarcodexia) tridentata (Hall) and Tricharaea (Sarcophagula) ramirezi (Lopes)] are new records for the Northeast region and eight are new records for the state of Maranhão. The species A. (A.) catiae, Blaesoxipha (Gigantotheca) stallengi (Lahille), D. pusilla, H. neuzalmeidae, Lipoptilocnema misella Lopes, Oxysarcodexia bakeri (Aldrich) and Retrocitomyia retrocita (Hall) were collected for the first time in pig carcasses. Peckia (Sarcodexia) lambens (Wiedemann) and Oxysarcodexia thornax (Walker) were the most abundant species. In both collection seasons, five species were carcasses pioneers at an early stage. The majority of species (42 spp.) were collected during the dry season, primarily during the black putrefaction (39 spp.) and butyric fermentation (30 spp.) stages. The greatest number specimens (n = 6,484) were recorded during the rainy season, at the butyric fermentation (n = 2,517) and black putrefaction (n = 2,080).

3D printed bionic ear and microtia-anotia: Medical and forensic implications.

Advances in science and technology result in continuous upgrading of the medical and clinical fields. These upgrades have been beneficial to many patients suffering from congenital and developmental diseases causing compromised functionality as well as the structural integrity of the affected organs. One such congenital anomaly is the microtia-anotia spectrum, which results in deformities of the external ear, affecting the hearing capability of an individual. The collaboration and integration of electronics in human biology are exemplified by the development of a 3D printed cyborg bionic ear from the patient's own cells, which is implanted to ameliorate microtia and improve the patient's hearing capacity. Since the late nineteenth century, forensic scientists have explored the external ear, establishing the significance of ear biometrics in the identification process. Similarly, ear prints can also play an important role in identifying the felon of a crime. In this regard, we examine the structure and functionality of implanted ears. This communication is an attempt to enlighten investigators on the forensic importance and limitations of the use of bionic ears for identification.

Analyzing the Forensic Significance of Tattoos and their Relevance in India

This research paper envisages to throw light on the forensic importance of tattoos in investigation and identificationfrom a global perspective. It also aims to analyze the relevance of tattoos in forensic science in India. The authorshighlight that with increased passion and popularity in body modification, sometimes, tattoos are the onlyevidence that the judiciary solely depends to identify and convict an accused. Thus, tattoos play a significant rolein criminal justice system. However, sole reliance on tattoos in this regard may not deliver precise conclusion asthere are psychopathological and scientific gaps involved.This research paper is divided into two segments – Part I and Part II, to analyze and substantiate the objective ofthe paper with judicial and legislative backing. Finally, the paper provides recommendations which may improvethe effectiveness of tattoos in forensic analysis and judicial proceedings in India.

Forensic importance of toolmarks evidence: A review

Forensic importance of toolmarks evidence: A review

Forensic Importance of Poroscopy in Age Estimation of the Fingerprint Donor and in Criminal Profiling

Fingerprints are unique patterns of ridges and valleys on the tips of fingers. The study of these unique patterns for the purpose of personal identification is called dermatoglyphics. These patterns are formed during fetal development and remain constant throughout a person's life, except in cases of permanent injuries and/or certain medical conditions. Fingerprint analysis, which involves the examination of the ridges on the fingertips, is a common method used in criminal investigations to identify suspects. Recently, pores present in the fictional ridges are also found to be having equal importance as the ridge minutiae characteristics in personal identification. Poroscopy as a ‘third level’ of fingerprint analysis can help the experts to identify criminals with their unique characteristic features such as the type of sweat gland openings, pore density, and shapes. This research focuses on studying the forensic importance of the pores present in the frictional ridges in estimating the age of the fingerprint donor, and in criminal profiling. 500 samples were collected to analyze the difference in the pore conditions between the genders and people of different age categories. The study showed significant results and the potential ability of the Poroscopy in personal identification and in criminal profiling.

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In the present investigation, 24 adult dipteran species with forensic importance belonging to 13 genera and 8 families that were collected from different localities of Iraq. The specimens were identified by different taxonomical keys; in addition the date and localities of collecting specimens were recorded.

Occurrence of necrophagous flies of forensic importance in medico-legal cases in Tamil Nadu State, India

BackgroundThe present study is based on the necrophagous fly samples collected from 24 medico-legal cases between the year 2011 and 2018 in Tamil Nadu State, India. The fly life stages were identified based on morphological features. Pre-autopsy condition of the human corpse colonized by necrophagous flies and indoor/outdoor occurrence of the flies were recorded.ResultsChrysomya megacephala, Chrysomya rufifacies, Sarcophaga spp, and Musca domestica life stages were collected from the human corpses. Chrysomya megacephala was the most prevalent (70.8%) insects of forensic importance and found both in indoor and outdoor environments. Drowned and burnt human corpses were found to be only colonized by C. megacephala. Chrysomya rufifacies was found only in outdoor environments and Sarcophaga spp was found only in indoor environment. There was a fair agreement between the percentage occurrence of necrophagous flies in human corpse in the present study in Tamil Nadu State and percentage historical occurrence of necrophagous flies in human corpse in India.ConclusionsChrysomya megacephala was the predominant blowfly species found to colonize corpses in Tamil Nadu State, India. Chrysomya megacephala was the only blowfly species found to colonize both burnt and floating corpses and corpses located indoor and outdoor.

Fall Decay Deceleration in Northern Latitudes: Merely a Matter of Cold?

The decomposition of cadavers and large vertebrate carcasses is the result of complex processes primarily influenced by ambient temperatures. Thus, low temperatures can alter decomposition by curtailing tissue autolysis and bacterial decomposition, and by limiting insect activity contributing to necromass removal. In this study, we tested whether carcass decomposition rate is modulated not only directly by temperature and insect occurrence, but also indirectly by the mediation of interactions among insects by ambient temperature. To test this, a comparative analysis of the decomposition of domestic pig carcasses in summer and fall was conducted in Atlantic Canada. The results indicated that carcass decomposition standardized to account for seasonal differences was significantly decelerated in the fall as opposed to the summer during the later decomposition stages and was sometimes incomplete. Moreover, the arrival, presence, and departure of insects from carcasses during ecological succession differed between summer and fall. Necrodes surinamensis (Fabricius) (Coleoptera: Silphidae) and Creophilus maxillosus (Linnaeus) (Coleoptera: Staphylinidae) maintained higher abundances late during succession in the fall than in the summer and their abundance was related to a decline in decomposition rates, probably because these species feed on dipteran larvae promoting necromass removal. These results demonstrate the variability in response to environmental parameters of insects of forensic importance and support the idea that slowed decomposition in the fall may be exacerbated by changes in interspecific interactions among insects. Furthermore, these results suggest that successional studies of insects carried out in the summer have little forensic utility for cadavers found in cold weather conditions.

High Temperature Limits of Survival and Oviposition of Phormia regina (Meigen) and Lucilia sericata (Meigen).

The temperature dependent development rates of blow flies allow blow flies to be used as biological clocks in forensic death investigations. However, the upper thermal limits of adult survival and oviposition, both required for producing larvae, remains largely unknown. Therefore, in this study we examined the impact of a range of temperatures between 37 °C and 44 °C on the likelihood of survival and egg-laying behavior of two species of medicolegal forensic importance, Lucilia sericata (Meigen) and Phormia regina (Meigen) (Diptera: Calliphoridae). To quantify the upper temperature limits of survival, adult fly colonies were exposed to 37 °C, 41 °C, 42 °C, 43 °C, and 44 °C for 24 h. Similarly for oviposition trials, adults of both species were exposed to 40 °C, 42 °C, and 43 °C with P. regina oviposition also observed at 41 °C. Trials lasted for 24 h with oviposition substrate replenished at the 12 h mark. A yes/no determination on egg deposition was made, eggs were counted, and a yes/no determination was made on egg hatch. Survival did not differ by species (p = 0.096). Overall, survival decreased with increasing temperatures, with ~100% at 37 °C, ~50% at 41 °C, ~37% at 42 °C, ~15% at 43 °C and 0% at 44 °C. Lucilia sericata laid eggs capable of hatch up to 43 °C, while Phormia regina egg-hatch was observed up to 41 °C. These results indicate a greater thermal tolerance of adult survival than for egg deposition and successful egg hatch, which supports previous experiments indicating blow flies stop laying eggs at sub-lethal temperatures. Furthermore, these data indicate that adult blow flies may find remains at or near time of death but may delay egg deposition until temperatures drop below an acceptable threshold.

Wing measurements are a possible tool for the identification of European forensically important Sarcophagidae

The flesh flies are a group of insects well known for their forensic importance. Reliable identification of these flies relies on the use of either molecular markers or the morphology of the male genital apparatus. Identification of female flesh flies is more time consuming and less reliable than their male counterparts. This is particularly problematic for forensic entomology practitioners, because female flesh flies are more abundant than males in carrion arthropod assemblages. As such, it is critical that alternative methods for flesh fly identification are established that are equally effective for both sexes. One promising technique is the use of wing measurements, which have been shown to be reliable for the identification of some groups of necrophagous Diptera from several geographical regions. We applied this method to the European Sarcophagidae for the first time, using a dataset of 881 specimens representing 29 species and 5 genera. Species identifications were based on 15 landmarks located at wing vein junctions. We also combined our results with data from previous studies of Calliphoridae and Muscidae which utilised the same methodology, enabling the testing of family level identification using wing morphometrics. Species identifications using wing measurements had varied success. While some species were successfully identified without error, others, particularly from the genus Sarcophaga, were often misclassified. Notably, in several species wing measurements successfully identified both males and females. The results presented here suggest that wing measurements are a promising complementary method to other methods for the identification of necrophagous Sarcophagidae especially in material unsorted at the family level. It can also be used to double check identification performed by a taxonomist using traditional methods.

Ultrastructural analysis of the antennae of Hemilucilia segmentaria (Diptera: Calliphoridae), a blowfly of forensic importance

Hemilucilia segmentaria (Fabricius, 1805) is a Neotropical blowfly species of forensic importance, with necrophagous and asynanthropic habits. In this study, the antennal ultrastructure of H. segmentaria was examined using scanning electron microscopy. The three antennal segments are covered by microtrichia. Sensilla chaetica were detected only on the scape and pedicel. Setiferous plaques and a pedicellar button were observed on the pedicel. Four types of sensilla were found on the postpedicel, including s. trichoidea, s. basiconica (subtype I, II and III), s. coeloconica subtype I, and sensory pits with s. coeloconica subtype II. This is the first time that the fine structure of the antennae of H. segmentaria was studied. Our results constitute a solid base for research on comparative and functional morphology in H. segmentaria and other blowflies.

Interactive Key for Third Instar Larvae of Neotropical Blow Flies (Insecta, Diptera, Calliphoridae): the Contribution of Computational Tools to Assist in Species Identification.

Calliphoridae (Insecta, Diptera), popularly known as blow flies or carrion flies, as most are necrophagous comprises one of the most relevant families of insects on forensics. Currently, more than 1500 blow fly species are known, the majority of which can be found in the Old World. In the Neotropics, it is estimated that there are approximately 20 species of forensic importance. In view of the taxonomic impediment associated with the identification of immatures, in this study, we present an interactive identification key for third instar larvae of necrophagous Calliphoridae species. This key includes 12 Neotropical blow fly species of forensic importance, more than 70 pictures, schemes, and definitions glossary and is free to access.

The cyclic nature of soil chemistry: Forensic analysis with the aid of ultra-high performance liquid chromatography

Despite its forensic importance as trace evidence, soil is under-utilised by forensic scientists due to a lack of research into the suitability of analytical approaches and a subsequent lack of understanding of the soil composition. Ultra-high performance liquid chromatography was used to analyse acetonitrile extractions from 210 soil samples taken from four locations across the Geelong and Surf Coast Shire areas of Victoria, Australia from March 2020 to January 2021. With the aid of principal components analysis of the UV-visible data chromatograms, it was found that this method could discriminate soil between locations, timepoints, and age points, and therefore, for the first time, shows that the method may offer a reliable method for forensic soil analysis. The approach used PCoA plots representing Bray-Curtis similarities comparing the UHPLC peak profiles which was able to show that the soil chemistry changes are cyclic, a factor that will help improve the utility of this approach for forensic analysis. As the separation was perfomred using a C18 column, the LDA scores suggest that hydrophobicity based on methyl selectivity may be important in spatial discrimination using this method. Further this type of approach generates a simple visual representation of the data that will be of value for presentation within a courtroom.

Temperature models of development for Necrodes littoralis L. (Coleoptera: Silphidae), a carrion beetle of forensic importance in the Palearctic region

Analysis of insects can provide evidence in death cases, for example, by answering the question about the time of death. Apart from flies, beetles are the second most useful insect group in forensic entomology. To elucidate the time of death based on insect evidence, developmental models of a given species are necessary. In this study, we developed such models for Necrodes littoralis, a necrophagous beetle, which is common in the Palearctic region and has great potential in forensic entomology. We monitored the development at 10 constant temperatures (14–30 °C). Larvae were reared in aggregations. Thermal summation models, isomorphen and isomegalen diagrams and growth curves were derived using the data. Depending on the temperature, development lasted between about 23 and 89 days. Mortality was high at the extremes of the temperature range. The thermal summation constant for the total development was 434.7 ± 28.86 accumulated degree-days above a developmental threshold of 9.04 ± 0.55 °C. This is the first comprehensive dataset on the development of N. littoralis. Implications for its use in forensic casework are discussed.