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The detection of toxic substances in larvae from carcasses in an advanced stage of decomposition may help criminal expertise in elucidating the cause of death in suspected cases of poisoning. Terbufos (Counter®) or O,O-diethyl-S-[(tert-butylsulfanyl)methyl] phosphorodithioate is an insecticide and systemic nematicide, which has very high toxicity from an acute point of view (oral LD50 in rodents ranging from 1.4 to 9.2 mg/kg) that has been marketed irregularly and indiscriminately in Brazil as a rodenticide, often being used to practice homicides. The present study aims to evaluate the use of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy to detect traces of terbufos pesticide in fly larvae (Sarcophagidae). ATR-FTIR spectra of scavenger fly larvae from control (n = 31) and intoxicated (n = 80) groups were collected and submitted to chemometric analysis by means of multivariate classification using principal component analysis with quadratic discriminant analysis (PCA-QDA), successive projections algorithm with quadratic discriminant analysis (SPA-QDA) and genetic algorithm with quadratic discriminant analysis (GA-QDA) in order to distinguish between control and intoxicated groups. All discriminant models showed sensitivity and specificity above 90%, with the GA-QDA model showing the best performance with 98.9% sensitivity and specificity. The proposed methodology proved to be sensitive and promising for the detection of terbufos in scavenger fly larvae from intoxicated rat carcasses. In addition, the non-destructive nature of the ATR-FTIR technique may be useful in preserving the forensic evidence, meeting the precepts of the chain of custody and allowing for counter-proof.

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The seasonal fluctuations of flesh fly (Diptera: Sarcophagidae) assemblages were investigated from March 2015 to February 2016 in five habitat types in the Humid Chaco ecoregion, Chaco Province, Argentina. Three of the habitats were anthropized: an urban area, a cattle farm, and an alfalfa crop; and two were natural: a savanna and a forest. Flesh flies were collected monthly at 25 sampling points, five per habitat. In total, 5,790 male specimens comprising 55 species distributed in 15 genera were collected. The assemblage composition of flesh flies in each habitat and season was analyzed in terms of abundance, species richness, and diversity. In addition, the correlation between these community parameters and climatic factors (precipitation 7 and 14 d before samplings, temperature, and relative humidity) were evaluated in each habitat. The highest abundance and species richness of Sarcophagidae were registered in May (autumn) and June (winter), respectively. The lowest diversity values were observed between August and September (end of winter and early spring) in all habitats. However, flesh flies were present and well represented (in terms of species richness) throughout the year in all habitat types. Fluctuations in the abundance of the most abundant species collected were analyzed. The climatic factors were correlated with diversity and species richness in the urban, cattle farm, and savanna habitats. This study revealed that flesh fly assemblages differed temporally between different types of habitats in accordance with climatic factors and microclimate conditions.

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A new Neotropical species of Oxysarcodexia Townsend (Diptera, Sarcophagidae) from Atlantic Forest of southeastern Brazil, Oxysarcodexia digitata sp. nov., is described and illustrated based on male and female specimens. This new species resembles O. fraterna Lopes, O. nitida Soares & Mello-Patiu, O. notata Soares & Mello-Patiu, O. vittata (Walker), and O. xon (Dodge), but can be distinguished based on differences in phallic elements. Additionally, the male of Oxysarcodexia xon (Dodge, 1968) is redescribed and illustrated, its female is described for the first time, and new records is presented.(AU)

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Field studies in forensic entomology seem to assume that a cadaver is a resource equally accessible to flies, irrespective of the species' size, behavior, and sensorial capacity. We aimed to challenge this assumption by experimentally manipulating baited traps in order to test whether the accessibility to decomposing baits is related to the following: (i) the diversity of necrophagous dipterans; (ii) the body size of adults; and (iii) the female sexual maturity stage. The experiment was performed in a rainforest fragment in Northeastern Brazil, in an area characterized by high levels of homicides. Traps baited with decomposing chicken liver had three levels of access: easy (six openings on the trap), intermediate (three), and difficult (one). A total of 750 adults of Calliphoridae, Fanniidae, Muscidae, Phoridae, and Sarcophagidae were collected. Of the 18 species recorded, Megaselia scalaris was the most abundant (46.8%) followed by Lucilia eximia (29.7%) and Chrysomya megacephala (9.8%). The number of species increased significantly with the accessibility level, but overall abundance did not differ, as a consequence of the numerical dominance of M. scalaris. A strong female bias (>91%) was observed in all traps. For Calliphoridae specimens, 90% of the females caught in traps under intermediate and difficult access were sexually mature. By empirically demonstrating that limitation of access and exclusion of visual stimuli do not deter several dipteran species from reaching a substrate, we expand the knowledge on the factors that can shape the colonization of concealed human cadavers, including variables such as insect size and stage of sexual maturity.

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Myiasis is defined as the infestation of living or necrotic tissues of vertebrates by dipteran larvae. In amphibians, it can be caused by fly larvae belonging to families Calliphoridae, Chloropidae, Muscidae, and Sarcophagidae. In this study, we report new records and infestation intensity of myiasis in anurans from two localities of the Atlantic Forest in southern Brazil, and also present a list with myiasis caused by flesh fly Sarcophagidae species in anurans of the Neotropical region. For this, we surveyed anuran communities during two breeding seasons, examined for myiasis signs, and when positive collected the specimens. We found infested individuals of 13 anurans of seven species. Different Sarcophagidae larva morphotypes were collected, and two of them emerged as adult flies of Lepidodexia (Notochaeta) fumipennis and Peckia (Sarcodexia) lambens, which were both found in the tree frog Bokermannohyla circumdata. We compiled 21 cases of myiasis in anurans in the Neotropical region from the literature reviewed. This data indicated that hosts of different lineages and modes of life can be affected and that death is often fast. The diversity of myiasis-causing flies in anurans in nature is probably a lot greater than expected, especially if we consider that the encounters are occasional, but at relatively high intensities, can cause rapid deaths.

Assuntos

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A new Neotropical species of Oxysarcodexia Townsend (Diptera, Sarcophagidae) from Atlantic Forest of southeastern Brazil, Oxysarcodexia digitata sp. nov., is described and illustrated based on male and female specimens. This new species resembles O. fraterna Lopes, O. nitida Soares & Mello-Patiu, O. notata Soares & Mello-Patiu, O. vittata (Walker), and O. xon (Dodge), but can be distinguished based on differences in phallic elements. Additionally, the male of Oxysarcodexia xon (Dodge, 1968) is redescribed and illustrated, its female is described for the first time, and new records is presented.

Assuntos

RESUMO

Abstract A new Neotropical species of Oxysarcodexia Townsend (Diptera, Sarcophagidae) from Atlantic Forest of southeastern Brazil, Oxysarcodexia digitata sp. nov., is described and illustrated based on male and female specimens. This new species resembles O. fraterna Lopes, O. nitida Soares & Mello-Patiu, O. notata Soares & Mello-Patiu, O. vittata (Walker), and O. xon (Dodge), but can be distinguished based on differences in phallic elements. Additionally, the male of Oxysarcodexia xon (Dodge, 1968) is redescribed and illustrated, its female is described for the first time, and new records is presented.

RESUMO

Techniques for the survey of necrophagous dipterans are frequently designed for adult flies and often neglect forensically important information, such as the postfeeding larval dispersal following carcass colonization. In this study, we propose and test a novel trap design for the collection of dipteran larvae at the postfeeding stage. The Trap for Dispersing Larvae (TDL) consists of two semiindependent parts: 1) a 2-liter PET bottle, containing the attractant (carcass); and 2) a plastic box, which selectively captures postfeeding dispersing larvae. Based on a field test in a dry forest fragment in Brazil, the TDL trap captured ca. 1,500 larvae of 13 species of Calliphoridae, Muscidae, Fanniidae, and Sarcophagidae. The species richness of dispersing larvae recorded in our study was ca. 60% of that previously recorded in this area. As the TDL trap can assess larval dispersal without interfering with carcass decomposition, we demonstrate that it can be used to assess temporal variation in the dynamics of colonization. In the present study, most larval dispersal occurred at 5-d postexposure, but the traps remained efficient until 7 d, by which time rat carcasses had skeletonized. We conclude that the TDL trap captures the dispersing dipteran larvae with little interference in carcass decomposition processes. The trap also provides a representative sample of species and is simple to use and of low cost.

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Abstract Introduction Myiasis is a disease causedby fly larvae that growinthetissues of animals and humans. It can cause a variety of local symptoms, like erythema or pain, depending on its location, and generalized symptomatology, such as fever andmalaise.Myiasis can generate severe complications, for instance sepsis, or directly impact vital tissues. Its management varies depending on the location, and on the preferences of the doctor that faces this challenge. Myiasis usually occurs in tropical countries, and, in many places, it is not a rare condition. The cases are rarely reported, and there are no publishedmanagement protocols. Objective To review the literature regarding the most common agents, the predisposing factors and the treatment alternatives for otic myiasis, a rare form of human myiasis caused by the infestation of fly larvae in the ear cavities. Data synthesis We present a systematic review of the literature. The search in five databases (Medline, Embase, Cochrane Database of Systematic Reviews, LILACS and RedALyC) led to 63 published cases from 24 countries, in the 5 continents. The ages of the patients ranged fromnewborn to 65 years old. Themost common agents belong to the Sarcophagidae or Calliphoridae families. Chronic otitis media, previous otic surgical procedures, mental deficit, alcohol or drug abuse, sleeping outdoors, prostration, and malnutrition were predisposing factors. The treatment alternatives are herein discussed. Conclusion The results highlight the need for monitoring, follow-up and standardization of medical approaches. (AU)

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Introduction Myiasis is a disease caused by fly larvae that grow in the tissues of animals and humans. It can cause a variety of local symptoms, like erythema or pain, depending on its location, and generalized symptomatology, such as fever and malaise. Myiasis can generate severe complications, for instance sepsis, or directly impact vital tissues. Its management varies depending on the location, and on the preferences of the doctor that faces this challenge. Myiasis usually occurs in tropical countries, and, in many places, it is not a rare condition. The cases are rarely reported, and there are no published management protocols. Objective To review the literature regarding the most common agents, the predisposing factors and the treatment alternatives for otic myiasis, a rare form of human myiasis caused by the infestation of fly larvae in the ear cavities. Data synthesis We present a systematic review of the literature. The search in five databases (Medline, Embase, Cochrane Database of Systematic Reviews, LILACS and RedALyC) led to 63 published cases from 24 countries, in the 5 continents. The ages of the patients ranged from newborn to 65 years old. The most common agents belong to the Sarcophagidae or Calliphoridae families. Chronic otitis media, previous otic surgical procedures, mental deficit, alcohol or drug abuse, sleeping outdoors, prostration, and malnutrition were predisposing factors. The treatment alternatives are herein discussed. Conclusion The results highlight the need for monitoring, follow-up and standardization of medical approaches.