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1. The necrobiome is a unique microcosm in which various organisms interact and compete for access to an ephemeral resource, such as carrion, that ultimately determines the structure and composition of these assemblages. 2. Blowfly species exhibit different competitive abilities which, when associated with other types of behaviour, such as predation or cannibalism, influence coexistence. Knowledge of the effects of competition between native and invasive species on development and survival is essential to understanding the dynamics of insect communities and to assess biological invasions. 3. Laboratory experiments were performed to evaluate the effect of interspecific competition on the bionomics and survival of a native (Cochliomyia macellaria) and an invasive (Chrysomya rufifacies) blowfly species at different population densities. 4. The deleterious effect of competition on the larval parameters of C. macellaria increased proportionally with increases in the larval density of C. rufifacies. When exposed to increased densities of C. rufifacies, larvae of C. macellaria accelerated their development and, as a trade‐off for this strategy, surviving adults were smaller and had reduced wing size, which were likely to reduce dispersal and reproductive capacity. 5. Larval competition – both as species‐dependent and density‐dependent phenomena – influences morphological and biological traits of surviving individuals. The impact of the invasive species has consequences at the population level, such as displacement or local population depletion of native species, a phenomenon likely to occur in other systems involving insects and ephemeral resources. [ABSTRACT FROM AUTHOR]

The expansion of agriculture in the semi-arid region of northeastern Brazil has been associated to an increase in the number of insect pests and the indiscriminate use of agrochemicals. We performed a field survey of two major okra pests, Aphis gossypii and Bemisia tabaci, taking into consideration their within-plant vertical distribution. We also investigated the presence of parasitized insects and the short-time effect of the application of deltamethrin. Throughout the experiment, 59,787 phytophagous insects were collected, which were categorized in four groups: healthy nymphs/adults of Aphis gossypii ( N = 31,767), A. gossypii parasitized by Hymenoptera ( N = 4189), Bemisia tabaci eggs ( N = 2507) and B. tabaci nymphs ( N = 21,324). The abundance of A. gossypii was higher than that of B. tabaci at both, the control and the insecticide-treated area. The frequency of parasitism of A. gossypii by Hymenoptera was higher in the areas that did not receive deltamethrin. Higher numbers of A. gossypii occurred in the middle part of the plants and B. tabaci populations were lower in apical leaves. [ABSTRACT FROM AUTHOR]

Data on the ecology and bionomics of necrophagous beetles are scarce in tropical countries despite their relevance in forensic investigations. We performed a survey on the diversity and temporal pattern of colonization of beetles on pig carcasses in a fragment of dry forest in northeastern Brazil. We collected 1550 adults of diverse feeding habits from 12 families, of which 96% had necrophagous and/or copronecrophagous habits and belonged to four families: Dermestidae, Scarabaeidae, Cleridae and Trogidae. Three species, Dermestes maculatus, Necrobia rufipes and Omorgus suberosus are reported for the first time with an expanded geographical distribution that includes the semi-arid region in Brazil. Adult beetles were collected as early as 24 h after death. One endemic species, Deltochilum verruciferum, stood out in terms of numerical dominance and temporal occurrence during different stages of decomposition. Its intimate association with carrion emphasizes their potential role in forensic entomology in the region. [ABSTRACT FROM AUTHOR]

In this study, a new species of Macrostemum is proposed based on adult males from Pernambuco state, Brazil. The new species can be diagnosed from its congeners mainly by the segment X with apex acuminate in lateral view, having a pronounced, narrow, deep, and U-shaped incision in dorsal view, by the presence of subbasal lateral setal warts, and by the dumbbell-shaped phallotremal sclerite in dorsal view. A key of male Neotropical Macrostemum species is also presented. Additionally, we provide five new caddisfly records for the Pernambuco state (Cernotina longispina, Helicopsyche tapadas, Macronema fragile, Triplectides gracilis, and Triplectides neotropicus); two of them constitute new records for the Brazilian Northeast region (Helicopsyche tapadas and Triplectides neotropicus), with Helicopsyche tapadas being recorded for the first time in the country. [ABSTRACT FROM AUTHOR]

Abstract: In a field survey performed in a malaria-endemic region of Northern Amazon, Brazil, we encountered ciliate protozoa of the family Tetrahymenidae infecting adults and larvae of the following mosquito species: Culex sp., Anopheles albitarsis l.s., Anopheles strodei, Anopheles mattogrossensis, Anopheles darlingi, and Anopheles oswaldoi l.s. Based on morphological features and life style, we have tentatively identified the parasite as Lambornella sp. The association appears pathogenic for the mosquito. Prevalence of infection in both larvae and adults was higher in the dry season. [Copyright &y& Elsevier]

Abstract: Baculovirus infection in Lepidoptera can alter both larval mobility and feeding rates, which can in turn affect pathogen transmission and dispersal in the field. We compared the damage to cabbage plants in the field caused by healthy and nucleopolyhedrovirus-infected Mamestra brassicae L. (Lepidoptera: Noctuidae) larvae released as second and fourth instars. There was no significant difference in plant consumption by healthy and infected larvae for the first 4 days after release. From day 5 onwards, infected larvae caused significantly less defoliation. This pattern was similar for larvae at both larval instars. Defoliation was greater for fourth instars throughout the experiment. [Copyright &y& Elsevier]

Environmental pressures challenge the survivorship of wildlife, and adaptive ability is key to their success and establishment. However, it remains unclear how changes in environmental conditions affect the phenotypic plasticity of some species. Studies that consider the effect of the environment (e.g., climate changes) on species morphology are essential to better understand his potential resilience. Thus, Diptera species appear as an excellent model. Here we investigated the effect of environmental conditions on wing size and shape within and between one native and one invasive blowfly species populations, along an ecoregional gradient in Brazil. For native species, wing size was affected by almost all environmental variables, while wing shape was unaffected. For invasive species, humidity best explained both wing size and wing shape variation. Our results show a differentiation between populations for both species, but a transversal comparison reveals that invasive species do not seem to be affected in the same way as the native species by climatic variations in the field. Temperature and humidity are the most significant environmental variables associated with differences in wing size and shape for invasive species, indicating an elevated climate tolerance of this species, which may be associated with its invasive characteristics and adaptive potential. Thus, our findings shed light on the importance of assessing the individual and compound effect of environmental variation and biological invasion on the adaptation of native species, since it is expected to increase 3 °C with a 20% overall reduction in the amount of rainfall in the tropical region of Brazil by 2100. [ABSTRACT FROM AUTHOR]

Species of the flesh fly subgenus Cucullomyia Roback (of genus Titanogrypa Townsend) are poorly studied and scarce in field samplings. Currently, eight species are described, distributed in the Neotropical and Nearctic regions, with six exclusively Neotropical species. The available descriptions and illustrations of some species of Cucullomyia lack sufficient detail to enable their accurate identification, and some issues regarding their subgeneric inclusion are debatable. Cucullomyia spp. have mainly been diagnosed by the peculiar shape of the male cercus, in particular the broader proximal half and the robust and rounded apex in lateral view, and by presenting a patch of white setulae on the sides of the scutellum, although there are exceptions in the colouration of these setae within the subgenus. This work presents redescriptions of the species, expands the distribution of some species in Brazil, and provides an identification key for the males. We discuss some diagnostic characters of Titanogrypa (Cucullomyia), such as the presence and colour of the patch of setulae laterally on the scutellum, as well as the limits of the vesica and juxta as the most important phallic structures for the segregation of the species of this taxon. Titanogrypa rubrigaster Dodge is transferred from the subgenus Cucullomyia to the nominative subgenus Titanogrypa. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Sarcophagidae or flesh flies are a highly diverse family of Diptera whose geographical distribution in the Neotropics is still poorly understood. We performed a two-year survey of flesh flies in fragments of Seasonally Dry Tropical Forests (SDTF) in Northeastern Brazil (Caatinga) using three types of substrate as baits: bovine spleen, fish and feces. Thirty-one species are registered, of which 13 are reported for the first time in SDTF. The highest diversity and abundance of flesh flies was associated with spleen. A strong female bias was observed in all samples. We discuss the medical, veterinary and forensic relevance and aspects of the synanthropy of the species registered for the first time in the Caatinga. [ABSTRACT FROM AUTHOR]

Unequivocal identification of fly specimens is an essential requirement in forensic entomology. Herein, a simple, non-destructive and rapid method based on two vibrational spectroscopy techniques [Near-Infrared Spectroscopy (NIRS) and attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy] coupled with variable selection techniques such as genetic algorithm-linear discriminant analysis (GA-LDA) and successive projection algorithm-linear discriminant analysis (SPA-LDA) were applied for identifying and discriminating six species of flesh flies (Diptera: Sarcophagidae) native to Neotropical regions. This novel approach is based on the unique spectral “fingerprints” of their biochemical composition. One hundred sixty (160) NIRS and FT-IR specimens (120 male, 40 female) were acquired; different pre-processing methods such as baseline correction, derivative and Savitzky-Golay smoothing were also performed. In addition, the multivariate classification accuracy results were tested based on sensitivity, specificity, positive (or precision) and negative predictive values, Youden index, positive and negative likelihood ratios. Principal components analysis (PCA) was employed for male vs. female category using NIRS, strongly showing the separation between the classes with only three principal components and 99% explained variance. Differentiation between the genera Oxysarcodexia, Peckia and Ravinia was efficiently confirmed by both techniques. In comparison with other biological methods, this approach represents an effective choice for fast and non-destructive identification in forensic entomology. [ABSTRACT FROM AUTHOR]