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Here we present a taxonomic treatment for the Brazilian species of Syrbatus (Reitter, 1882), including the description of three new species (Syrbatus moustache Asenjo & Valois sp. nov., Syrbatus obsidian Asenjo & Valois sp. nov. and Syrbatus superciliata Asenjo & Valois sp. nov.) from the Quadrilátero Ferrífero (Minas Gerais, Brazil). In addition, we designated lectotypes for the Brazilian species of species-group 2, Syrbatus centralis (Raffray, 1898), Syrbatus hetschkoi (Reitter, 1888), Syrbatus hiatusus (Reitter, 1888), Syrbatus transversalis (Raffray, 1898), and Syrbatus trinodulus (Schaufuss, 1887), besides recognizing the holotype for Syrbatus brevispinus (Reitter, 1882), Syrbatus bubalus (Raffray, 1898), and Syrbatus grouvellei (Raffray, 1898). The mitochondrial genomes (mitogenomes) of the three new species are presented, for which we present the phylogenetic placement among Staphylinidae with previously published data.

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Only a few cases describing the activity of dermestids on human corpses have been reported in the literature. Dermestes maculatus is a cosmopolitan beetle associated with carcasses at different decomposition stages, usually colonizing skeletonized and mummified remains. In this study, we presented two forensic case reports of D. maculatus associated with human corpses in Santa Catarina State, southern Brazil. In the first case, a human corpse in an advanced stage of decomposition was found hanged in an outdoor urban area. In the other one, a mummified cadaver was found inside of a closed house. In this last case, larvae of D. maculatus were essential to estimate the minimum postmortem interval (PMI) for the first time in Scientific Police of Santa Catarina. Our records highlight the significance of necrophagous beetles in ecological succession and in estimating PMI in cases involving human remains and corpses in advanced stage of decomposition.

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Tribolium castaneum, also known as the red flour beetle, is a polyphagous pest that seriously damages agricultural products, including stored and processed grains. Researchers have aimed to discover alternative pest control mechanisms that are less harmful to the ecosystem than those currently used. We conduct the purification and characterization of a protease inhibitor from C. plumieri seeds and an in vitro evaluation of its insecticidal potential against the insect pest T. castaneum. The trypsin inhibitor was isolated from C. plumieri seeds in a single-step DEAE-Sepharose column chromatography and had a molecular mass of 50 kDA. When analyzed for interaction with different proteolytic enzymes, the inhibitor exhibited specificity against trypsin and no activity against other serine proteases such as chymotrypsin and elastase-2. The isolated inhibitor was able to inhibit digestive enzymes of T. castaneum from extracts of the intestine of this insect. Therefore, we conclude that the new protease inhibitor, specific in tryptic inhibition, of protein nature from the seeds of C. plumieri was effective in inhibiting the digestive enzymes of T. castaneum and is a promising candidate in the ecological control of pests.

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OBJECTIVES: Colorectal endoscopic submucosal dissection (ESD) is a technically complex procedure. The scissor knife mechanism may potentially provide easier and safer colorectal ESD. The aim of this meta-analysis is to evaluate the efficacy and safety of scissor-assisted vs. conventional ESD for colorectal lesions. METHODS: A search strategy was conducted in MEDLINE, Embase, and Lilacs databases from January 1990 to November 2023 according to PRISMA guidelines. Fixed and random-effects models were used for statistical analysis. Heterogeneity was assessed using I2 test. Risk of bias was assessed using the ROBINS-I and RoB-2 tools. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation tool. RESULTS: A total of five studies (three retrospective and two randomized controlled trials, including a total of 1575 colorectal ESD) were selected. The intraoperative perforation rate was statistically lower (risk difference [RD] -0.02; 95% confidence interval [CI] -0.04 to -0.01; P = 0.001; I2 = 0%) and the self-completion rate was statistically higher (RD 0.14; 95% CI 0.06, 0.23; P = 0.0006; I2 = 0%) in the scissor-assisted group compared with the conventional ESD group. There was no statistical difference in R0 resection rate, en bloc resection rate, mean procedure time, or delayed bleeding rate between the groups. CONCLUSION: Scissor knife-assisted ESD is as effective as conventional knife-assisted ESD for colorectal lesions with lower intraoperative perforation rate and a higher self-completion rate.

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Tribolium castaneum and Rhyzopertha dominica are cosmopolitan, destructive postharvest pests. Although research has investigated how high densities of T. castaneum affect attraction to the aggregation pheromone by conspecifics, research into the behavioral response of both species to food cues after high density exposure has been lacking despite its importance to foraging ecology. Our goal was to manipulate and observe the effects of crowding on the behavioral response of both species to common food and pheromonal stimuli and to determine how the headspace emission patterns from grain differed under increasing densities. Densities of colonies for both species was altered (10-500 adults) on a fixed quantity of food (10 g of flour or whole wheat), then the behavioral response to common food and pheromonal cues was evaluated in a wind tunnel and release-recapture experiment, while volatiles were examined through gas chromatography coupled with mass spectrometry. Importantly, at least for T. castaneum, crowded conditions attenuate attraction to food-based stimuli, but not pheromonal stimuli. Crowding seemed to have no effect on R. dominica attraction to food and pheromonal stimuli in the wind tunnel, but exposure to high density cues did elicit 2.1-3.8-fold higher captures in traps. The relative composition and abundance of headspace volatiles emitted varied significantly with different densities of beetles and was also species-specific. Overall, our results have implications for expanding our understanding of the foraging ecology of two economically important pests.

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Euwallacea fornicatus is an invasive tree pest able to infest healthy plants and cause damage to many host plants. This beetle has become established in several countries where it was introduced. It has now become established in Brazil, and while the original introduction site remains uncertain, there is a possibility of multiple introductions. We report the first evidence for the establishment of E. fornicatus with molecular confirmation, as well as its distribution, and host plants in Brazil. Euwallacea fornicatus has spread to main commercial avocado groves, other monocultures, and native vegetation in the country, and its pest status puts it as a threat, mainly to Brazilian avocado producers.

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BACKGROUND: Wheat grain containers or silos can be perfect habitats for insects, which generate large economic losses to grain production. Natural alternatives to synthetic insecticides have grown in popularity because of health, economic and ecological issues. Diatomaceous earth is a natural compound that has an insecticide effect by enhancing an insect's dehydration with no toxicity on mammals including humans. The aim of this study is to confirm the effect of diatomaceous earth as an insecticide for the wheat grain pest, the red flour beetle Tribolium castaneum (Coleoptera: Tenebrionidae) and demonstrate its underlying mechanisms as an insecticide by open-flow respirometry and scanning electron microscopy. RESULTS: Survival bioassays of T. castaneum revealed a dose-dependent insecticide effect of diatomaceous earth. Gravimetric measurements showed that 2 days exposure to diatomaceous earth produces a significant increase of mass loss. Open-flow respirometry measurements showed an increase of total water emission rate on insects due to an increase of both, respiratory and cuticular water loss. Our study revealed that diatomaceous earth produces an increase of insect's cuticle permeability, which is responsible for elevated cuticular water loss. Scanning electron microscopy images provided visual evidence of the lipid absorbent properties of diatomaceous earth particles, and showed a tendency for higher, although not significant, damaged area of the cuticle's surface from diatomaceous earth treated insects compared to control ones. CONCLUSION: With state-of-the art techniques like open-flow respirometry and scanning electron microscopy, we demonstrated the underlying mechanism of diatomaceous earth as an insecticide and provided new cues for understanding the properties of the cuticle and its ecological importance. © 2024 Society of Chemical Industry.

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Dihammaphora Chevrolat (Arc Nat 1:50-54, 1859) is one of the most diverse genera of Rhopalophorini, with 46 species. It is characterized mainly by species with antennae short and subserrated, with 10 or 11 antennomeres, prothorax cylindrical, and elytra punctuated. In this study, two new species of Dihammaphora are described and illustrated, new records are provided to 11 species, and taxonomic notes are given to six species of the genus. We examined 55 specimens and identified 16 species of the genus Dihammaphora, including Dihammaphora aurea sp. nov. from Honduras, and Dihammaphora cruzi sp. nov. from Brazil. The number of species of Dihammaphora is increased to 48, two of them in Central America, resulting in seven species for this region. In Brazil, 24 species are now recognized, being the country with the largest number of species of the genus. This study shows that there is still a deficit of knowledge about the diversity and distribution of Dihammaphora.

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When colonizing new ranges, plant populations may benefit from the absence of the checks imposed by the enemies, herbivores, and pathogens that regulated their numbers in their original range. Therefore, rates of plant damage or infestation by natural enemies are expected to be lower in the new range. Exposing both non-native and native plant populations in the native range, where native herbivores are present, can be used to test whether resistance mechanisms have diverged between populations. Datura stramonium is native to the Americas but widely distributed in Spain, where populations show lower herbivore damage than populations in the native range. We established experiments in two localities in the native range (Mexico), exposing two native and two non-native D. stramonium populations to natural herbivores. Plant performance differed between the localities, as did the abundance of the main specialist herbivore, Lema daturaphila. In Teotihuacán, where L. daturaphila is common, native plants had significantly more adult beetles and herbivore damage than non-native plants. The degree of infestation by the specialist seed predator Trichobaris soror differed among populations and between sites, but the native Ticumán population always had the lowest level of infestation. The Ticumán population also had the highest concentration of the alkaloid scopolamine. Scopolamine was negatively related to the number of eggs deposited by L. daturaphila in Teotihuacán. There was among-family variation in herbivore damage (resistance), alkaloid content (scopolamine), and infestation by L. daturaphila and T. soror, indicating genetic variation and potential for further evolution. Although native and non-native D. stramonium populations have not yet diverged in plant resistance/constitutive defense, the differences between ranges (and the two experimental sites) in the type and abundance of herbivores suggest that further research is needed on the role of resource availability and adaptive plasticity, specialized metabolites (induced, constitutive), and the relationship between genealogical origin and plant defense in both ranges.

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Astylus atromaculatus is a pollen beetle native to South America, commonly found in crop flowers. Experimental intoxication of sheep and guinea pigs by this beetle resulting in fibrinonecrotizing enteritis has been reported. We describe here 6 natural outbreaks of intoxication in cattle associated with consumption of alfalfa (5 of 6) and mixed native (1 of 6) pastures heavily contaminated with A. atromaculatus. The outbreaks occurred during the summer (January-February) of 2023 in Argentina (n = 4) and Uruguay (n = 2), in beef cattle under extensive or semi-extensive rearing systems, with overall cumulative incidence and mortality of 22.3% and 17.8%, respectively. The main clinical signs included acute onset of anorexia, lethargy, hyperthermia, hindlimb weakness, reluctance to move, and diarrhea, for up to 15 d. In 2 outbreaks, sudden death was observed. Eight Hereford, Angus, and/or crossbreed heifers, cows, steers, and/or calves were autopsied. Gross and microscopic findings included multifocal necrosis with fibrinous pseudomembranes in the forestomachs and/or small and large intestines. Fragments or whole specimens of A. atromaculatus were identified in the ruminal content of all animals. Testing for multiple gastroenteric pathogens was negative as was testing of A. atromaculatus for cantharidin and batrachotoxin. GC-MS and LC-MS/MS performed on the beetles did not identify any known toxic compounds. Based on the exposure to A. atromaculatus-contaminated pasture, gross and microscopic lesions, and negative results of all testing for multiple gastroenteric pathogens, a diagnosis of intoxication by A. atromaculatus is proposed. Disease caused by A. atromaculatus consumption has not been reported previously in cattle, to our knowledge.

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ABSTRACT Great advances were made in recent years regarding the description of immatures of Cassidinae and their taxonomy as a whole, but many taxa remain undescribed. This study focuses on updating morphological data for Hybosa acutangula Spaeth, 1913 (Chrysomelidae: Cassidinae: Ischyrosonychini), a tortoise beetle native of South America, which was collected in Fridericia florida (DC.) L. G. Lohmann in the Brazilian Cerrado. We provide descriptions and illustrations of the morphology of the larva, pupa, and genitalia of adults, all of which are novel for this genus. The main discerning features for this species among other Ischyrosonychini are the lack of dark patterns in the dorsum of either the larvae, being limited to the dark scoli and the cranium, or the pupae, and a much reduced anal fork. We also present the first record of parasitism by Chalcididae wasps, Brachymeria sp. Westwood, 1832 and Conura sp. Spinola, 1837. Morphological comparisons remain limited demanding further studies with other species of Ischyrosonychini, as to better understand the placement of this species within the taxonomy of tortoise beetles.

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The current knowledge of morphology and chaetotaxy of the different developmental stages within the subfamily Scolytinae presents an information deficit that needs to be addressed. Thus, the objective of the present study was to describe, the chaetotaxy and morphology of larvae and pupae, and determine the number of larval instars, the sexual dimorphism in adults, and the development time in Phloeosinus tacubayae. The number of larval instars was determined using traditional morphometry of cephalic capsule and multivariate analysis; description of morphology and chaetotaxy of larvae and pupae, and sexual dimorphism in adults was based on light microscopy and scanning electron microscopy photographs; finally, we quantified development time by mean reviews of 10 gallery systems selected randomly in infested logs, in the laboratory. Morphometric analysis of the cephalic capsule allowed the recognition of 3 different instars. Our results showed that the larvae of P. tacubayae have unique attributes in the body that differentiate them from other genera of the subfamily for example the epicranial suture is not marked, and differentiated from Phloeosinus canadensis, such as a smaller number of setae in the maxillae and without a tergal plate. The pupa had a smaller number of setae on the whole body. The most useful morphological characters to identify a sexual dimorphism in adults were found in the shape and relative position of the seventh and eighth tergites; development time lasted 40 days in total, being the pupal stage the one that took the longest to complete.

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We investigated the male and female reproductive tracts of Gyretes sp. with light and transmission electron microscopies. The male has a pair of testes with a single coiled follicle, followed by short efferent ducts, which have a similar shape and diameter to the testes. Long ducts (epididymides) with differential epithelium open in a pair of long vasa deferentia that lead to the accessory glands. Glycoprotein secretions from the vas deferens epithelium constitute the spermatostyle for spermatozoa aggregation. The female has numerous ovarioles per ovary, a coiled fertilization duct, an accessory gland, and an elongated vagina. Spermatozoa are stored as unaggregated cells in the fertilization duct. In Gyrinidae, the testes and accessory glands show diverse shapes, and the female sperm storage organs vary in shape, size, and type and may play a role in the interaction with sperm aggregates. Testes with a single follicle and vasa deferentia opening in the accessory glands of Gyretes sp. are features shared with other Gyrinidae and other Adephaga. We proposed adding this latter trait to characterize this suborder of beetles. The morphology of the reproductive organs in both sexes contributes to comparative analyses and knowledge of the reproductive biology of Gyretes and may provide additional features for systematics.

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Damage from Sinoxylon anale Lesne, a woodboring beetle not previously known to be established in Brazil, was observed in young jabuticaba trees (Plinia cauliflora, Myrtaceae) in a nursery in the municipality of Laranjal Paulista, state of São Paulo. We immediately advised MAPA ("Ministério da Agricultura, Pecuária e Abastecimento") and collected samples from the nursery and from different hosts in nearby areas, to identify the specimens and investigate the dynamics of the infestation in the jabuticaba trees. Sinoxylon anale was also collected in ethanol-baited and ultraviolet-light traps and in dry branches of the native species pau-jacaré (Piptadenia gonoacantha, Fabaceae) and inga (Inga vera, Fabaceae), and the exotic pau-d'água (Dracaena fragrans, Asparagaceae) in the municipality of Piracicaba, state of São Paulo. These collections established that S. anale larvae and adults develop in dead branches of four new host plants. Taxonomic studies using morphological parameters and DNA barcoding confirmed the identification of S. anale. An illustrated key to the three Sinoxylon species now recorded in Brazil is provided, and the COI gene sequences have been made available in a public database. Sinoxylon anale probably attacked the young jabuticaba trees after they were killed by larvae of long-horned beetles (Cerambycidae). So far, S. anale has been found established only in two locations in the same area of the state of São Paulo.

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In the present study, we explored the effects of displacement directionality in mating behavior (i.e., lateralized and non-lateralized movements) on mating success (i.e., copulation occurs) and efficiency (i.e., time length at which copulation is achieved), and its association with sex and sexual experience in A. diaperinus. To do so, we carried out mating experiments and recorded the behavior of the mating pair during the whole mating sequence (i.e., precopulatory and copulatory phases). During the precopulatory phase, independently of sex and sexual experience, all beetles performed non-lateralized (i.e., backside or frontside) approaches; however, only sexually experienced beetles showed lateralized approaches (i.e., right-side and left-side). Notably, experienced males exhibited greater mating success than virgin males. After the approach, both virgin and experienced males displayed lateralized and non-lateralized mounts on the females with distinct mating success. Regardless of their sexual experience, 100% of successful mating attempts were achieved when males mounted from the females' right side. Furthermore, the development of lateralized approaches and mounts reduces the time of mating sequence span compared with non-lateralized behaviors. We highlight the importance of lateralization in mating behavior and sexual experience to achieve higher mating success, addressing a potential learning ability of beetles based on experience.

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Mexico is a major honey producer, but not much information exists about the health status of honey bees (Apis mellifera L.) in the country. This study was conducted to determine the sanitary status of adult honey bees in Mexico's five beekeeping regions. Samples from 369 apiaries were diagnosed to identify pathogens such as Varroa destructor, which was quantified, Acarapis woodi, Nosema spp., and five viruses. Colonies were also inspected for the presence of the small hive beetle (SHB), Aethina tumida. Varroa destructor was found in 83.5% of the apiaries, with the Pacific Coast region having the highest prevalence (>95%) and rates (4.5% ± 0.6). Acarapis woodi was detected in only one apiary from the Pacific Coast, whereas Nosema spp. were prevalent in 48.5% of the apiaries, with the highest and lowest frequencies in the Yucatan Peninsula and North regions (64.6% and 10.2%, respectively). For viruses, deformed wing virus (DWV) was detected in 26.1% of the apiaries, with the highest frequency in the Pacific Coast region (44.7%). Israeli acute paralysis virus (IAPV) was diagnosed in 3.2% of the samples and sacbrood bee virus (SBV) in 23.3% of them, with the highest frequency in the High Plateau region (36.4%). Chronic bee paralysis and Kashmir bee viruses were not detected. SHB prevalence was 25.2% nationwide, with the highest frequency in the Yucatan Peninsula (39.2%). This study shows that the most common parasites of adult honey bees in Mexico are V. destructor and Nosema spp., and that the most prevalent virus is DWV, whereas SHB is highly prevalent in the Yucatan Peninsula. This information could be useful to design disease control strategies for honey bee colonies in different regions of Mexico.

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Metopiellus Raffray, 1908 is a genus of South American rove beetles typically found in tropical humid forests. Here we describe a new cryptic species from Eastern Amazon, in northern Brazil, Metopiellus crypticus Asenjo sp. nov., and its major morphologic diagnostic features, which were photographed and illustrated. In addition, we bring the complete mitochondrial genome sequence of M. crypticus sp. nov., and its position within the phylogenetic context of the family, including previously available mitogenomes of Staphylinidae species.

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Jamaica produces coffee marketed as Blue Mountain and high mountain (grown outside the Blue Mountains). Since the discovery of the coffee berry borer (CBB; Hypothenemus hampei) in Jamaica in 1978, chemical control has traditionally been the primary approach used to protect the crop from the pest. However, in the last 20 years, there has been an effort to shift towards more sustainable management strategies. The study was conducted to determine CBB activity (trap catch) and field infestation on coffee farms in the high mountains and Blue Mountains of Jamaica, over a crop cycle. A total of 27,929 and 12,921 CBBs were captured at high mountain and Blue Mountain farms, respectively. Peak CBB activity occurred in April in the high mountain region (365 CBBs/trap/month) and February in the Blue Mountain region (129 CBBs/trap/month). The highest levels of infestation were in November (33%) and October (34%) in the high mountain region and Blue Mountain region, respectively. There was no significant difference in the patterns of CBB activity and infestation between the study locations, and neither were related to the temperature or relative humidity. However, there was a significant relationship with rainfall. These data suggest that the population dynamics of the CBB may involve complex interactions among weather conditions, berry development, and agronomic practices.

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Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) is a major pest of common bean (Phaseolus vulgaris L.; Fabales: Fabaceae), and adults can defoliate plants during the whole crop cycle. This study was conducted to evaluate the resistance to D. speciosa in 16 common bean genotypes (14 landraces and 2 cultivars), through three different experiments. In the laboratory, choice and no-choice feeding tests were performed to evaluate the percentage of leaf consumption. In the greenhouse, plant height, numbers of leaves, percentage of injured leaves, percentage of injury per leaf, weight of seeds, and D. speciosa survival were evaluated. Furthermore, trichome density, levels of peroxidase (POD), superoxide dismutase (SOD), and protein content in common bean leaves were assessed. In the laboratory, the genotypes Chumbinho Branco, Dobalde, Manteigado, IPR Tuiuiú, and 90D Mouro were the least consumed by D. speciosa. In the greenhouse, the genotypes Dobalde, Manteigado, and IPR Tuiuiú expressed tolerance to the pest, which was associated with a higher plant height and/or unchanged POD and SOD levels and protein content following insect feeding, and no reduction in seed production. The landrace 90D Mouro exhibited antixenosis and tolerance to D. speciosa, observed as a lower leaf injury, higher trichome density, lower protein contents, higher SOD level and no reduction in seed weight. Overall, we have shown that antixenosis and tolerance can help overcome damages resulting from D. speciosa feeding, with emphasis on four common bean genotypes that may be useful in plant breeding programs aimed at controlling D. speciosa in common bean crops.

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The use of recovered DNA ingested by necrophagous or hematophagous insects has increased in forensic sciences, mainly with representatives of flies. However, some beetles are also important for medico-legal forensic entomology because they feed on carcasses until advanced decomposition. This study evaluated whether the Neotropical carrion beetle Oxelytrum discicolle (Silphidae) has the potential for the detection of exogenous DNA into the gut. The whole gut or the gut contents were extracted from O. discicolle larvae and adult previously fed on pig carcass. The pig DNA recovery rate was 33.3% in larvae and 25% in adults, indicating that the carrion beetle's gut may be useful for DNA identification of ingested food. Samples with the whole gut or only gut contents showed the same DNA recovery rate. Exogenous DNA from the whole gut was recovered from samples stored in ethanol at -20 ºC for 11 days, showing that samples of O. discicolle can be stored in the forensic laboratory without loss in DNA recovery rate.

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