Neotropical Entomology最新文献

Aedes aegypti transmits the arboviruses that cause dengue, zika, and chikungunya. Entomopathogenic fungi are beneficial microorganisms that can be incorporated into current strategies against mosquitoes of public health concern. This study molecularly identified the Metarhizium anisopliae CG 153 isolate and evaluated its virulence against larvae, pupae, and adults (both males and females) of Ae. aegypti. Different concentrations of conidia were used (1 × 10^4-8 conidia mL^-1). Larval and pupal survival was monitored daily for seven and three days, respectively, while adults were monitored for 15 days. The efficacy of M. anisopliae sensu stricto was concentration-dependent, with higher concentrations achieving better results, demonstrating greater virulence against larval and adult stages of Ae. aegypti. The fungus reduced the larval survival by 95,5% (1 × 10⁸ con.mL^-1), 94,4% (1 × 10⁷ con.mL^-1), 78,9% (1 × 10⁶ con.mL^-1), 62,2% (1 × 10⁵ con.mL^-1), and 41,1% (1 × 10⁴ con.mL^-1) after seven days. Adults also showed susceptibility to the fungus, with no observed difference in susceptibility between males and females. Over 15 days of monitoring, adult survival rates ranged from approximately 6.7% to 72%. Pupae exhibited lower susceptibility to the fungus across different concentrations, with survival rates ranging from approximately 87.8% to 100%. This study highlights the high effectiveness of M. anisopliae CG 153 against both Ae. aegypti larvae and adults (male and female) under controlled conditions, suggesting its promising potential for further evaluation and application in field conditions.

Oncopodura are rare basal springtails often associated with caves; only O. hyleana and O. itatiaiensis are known to Brazil. Oncopodura specimens from CRFS-UEPB were analyzed. Four new species are described: O. aurea sp. n., O. bauxita sp. n., O. hematita sp. n., and O. turmalina sp. n. The coded description of Symphypleona is adapted to Arthropleona, and 96 morphological characters are listed. Data of habitat and distribution of the new species is presented. A key of Brazilian Oncopodura is provided. Oncopodura groups are analyzed with main morphological characters for the groups classification. The crassicornis group is paraphyletic, tricuspidata group is monophyletic, and cruciata group compounds a new group out tricuspidata, with uncertain classification. The main characters that support crassicornis are the presence of unguiculus basal tubercle, external pretarsal chaeta larger than internal, absence of lateral lamella on unguis and PAO often with 6 + 6 or more lobules; tricuspidata is supported by basal tubercle often absent, pretarsal chaetae with similar length (usually both small), presence of lateral lamella on unguis and PAO often with less than 4 + 4 lobules; cruciata group is supported by absence of lateral lamella on unguis and PAO with less than 4 + 4 lobules and pretarsal chaetae usually with same length, both large. The characters like number of PAO lobes and shape, number of Ant IV transversal sens, and shape of hooks of the dens apparently are adaptive, presenting variations in the species. All the newly described species have reduced abundance and are distributed along two of Brazilian major mining areas, and are subject of habitat loss and degradation.

Investigation of the diversity of lacewings (Neuroptera: Chrysopidae) is crucial in agricultural systems, as these insects are important predators of many pest species. Recent studies have shown that height influences the abundance and richness of insects. Information on these factors is scarce for species of Chrysopidae at different heights in agricultural and forest environments. This study aimed to evaluate the influence of height on the abundance and richness of green lacewings in an anthropically modified environment. Multilure traps baited with putrescine and ammonium acetate were placed in four areas of the "Luiz de Queiroz" Campus (Piracicaba, São Paulo State, Brazil) at two heights (2 and 10 m) from April 2019 to March 2020. Species captured in traps hung at 2 and 10 m above the ground surface were studied with the faunistic analysis ANAFAU, using ecological parameters and diversity indices. The similarity between the species was measured using the Morisita-Horn coefficient. Thirteen species of Chrysopidae were captured, and more species and specimens of green lacewings were collected with the traps at 2 m than at 10 m, that is, height influenced the abundance and richness of the lacewing species. Leucochrysa (Nodita) cruentata (Schneider) was predominant in most areas studied. The highest diversity and abundance of green lacewings was observed on Areão farm in trap at 2 m height. However, Ceraeochrysa claveri (Navás) and Ce. everes (Banks) showed a more similar ecological pattern. Multilure traps baited with putrescine and ammonium acetate were effective in sampling green lacewings, mainly at 2 m height.

Insecticides are widely used to control pests and improve agricultural yield. The use of indiscriminate amounts and persistent pesticides has not only resulted in insect pest resistance challenges but has also harmed non-target organisms and contaminated the environment. We assessed the cost-effectiveness of Spodoptera litura (Fabricius) resistance to chlorantraniliprole (CTPR) as part of insect resistance control programs. S. litura larvae were collected from the fields and treated with chlorantraniliprole for 15 generations. Compared to the unselected population (Unsel-Lab), the chlorantraniliprole-selected population (CTPR-Sel) of S. litura exhibited a resistance level of 98.23 times. The findings demonstrated that the chlorantraniliprole-resistant genotype had lower egg-to-adult survivability, longer egg-to-adult developing times, and lower fecundity than the chlorantraniliprole-susceptible genotype. Compared to the Unsel-Lab population, the CTPR-Sel population of S. litura had a poorer relative fitness (0.44) at LC₃₀ and shorter male/female longevity. Demographic parameters, including net reproductive rate (R₀) and intrinsic (r_m) and finite rate of increase (λ), were lower in the CTPR-Sel strain than in Unsel-Lab S. litura. These findings demonstrate that chlorantraniliprole resistance in S. litura has fitness costs at the individual and population levels, implying that removing the selecting agent from the environment might result in less resistance and opportunities for susceptibility restoration. As a result, the current work could help to determine effective management strategies to prevent chlorantraniliprole resistance in S. litura.

The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), is a major agricultural pest known for developing resistance to insecticides. This study investigated a novel approach to manage FAW by silica nanoparticles (SiNPs) synthesized from eco-friendly leaf extract of Moringa oleifera Lam. (Moringaceae). This green synthesis method offers a sustainable and potentially safer alternative to traditional chemical processes. SiNP formation was confirmed by various techniques: UV-visible spectrophotometer, X-ray spectroscopy with energy-dispersive (EDX), scanning electron microscopy (SEM), and dynamic light scattering (DLS). The effectiveness of SiNPs alone and their combination with three common insecticides (emamectin benzoate, indoxacarb, and chlorpyrifos) were evaluated against third instar larvae of fall armyworm. While SiNPs after 24 h by leaf dipping method recorded limited insecticidal activity (LC₅₀ = 9947.59 mg/L), it significantly enhanced the potency of all three insecticides. Combining SiNPs with emamectin benzoate resulted in the most dramatic increase in effectiveness compared to the insecticide alone with LC₅₀ = 0.295 mg/L and 0.42 mg/L, respectively. This research suggests that moringa extract can be a valuable resource for the green synthesis of nanoparticles potentially useful in pest control. This approach could potentially reduce the amount of insecticide needed for effective pest control, leading to a more sustainable and environmentally friendly agricultural practice.

The environment where bee colonies are inserted must provide the necessary resources for their survival. Given this, any biotic and abiotic changes in the environment can affect the development and survival of the colonies. We evaluated the foraging activity of Plebeia droryana (Friese), Scaptotrigona bipunctata (Lepetelier), and Melipona quadrifasciata (Lepetelier) in areas with different land uses and land cover. These areas were classified as predominantly (i) urbanized/forest (CDA-Cidade das Abelhas), (ii) agricultural (FER-Fazenda Experimental da Ressacada), and (iii) with dense vegetation (SFB-Sitio Florbela). We correlated the morphometric characteristics of the bees with the pollen load transported. Four colonies from each species were installed in the three areas. We recorded light, wind speed, humidity, and temperature and counted the foragers returning with nectar, pollen, and resin. Plebeia droryana and S. bipunctata collected more resin and nectar in with dense vegetation area compared to agricultural area. Scaptotrigona bipunctata collected more pollen in urbanized/forest area and with dense vegetation area, and M. quadrifasciata did not show differences in foraging activity between areas. Plebeia droryana and M. quadrifasciata showed moderate and strong correlations between morphometric characteristics and pollen load. SFB had higher luminosity and wind speed. CDA had higher average temperature. FER had higher humidity. The three species showed positive and negative correlations between temperature and light and foraging in the different areas. Smaller species showed a higher gathering of resources in the area predominantly covered by dense vegetation. The reduction of vegetation cover can affect the resource collection activity of stingless bees.

Raspberries (Rosales: Rosaceae) are considered to be one of most important crops in northwestern Morocco. However, this sector is seriously affected by the attack of Drosophila suzukii, which impairs the production and the export. Furthermore, the eco-ethology and population dynamics of D. suzukii under Moroccan conditions are still poorly understood. In Larache region, we monitored the population dynamics of D. suzukii adults using 4 traps baited with mashed ripe banana mixed with yeast, and reported the infestation levels during spring of 2022, 2023, and 2024 on raspberry cultivar Rubus idaeus var. Yazmin. Our results indicate that a maximum of 14, 20, and 28 D. suzukii adults per trap were caught weekly at the end of April 2022, in the middle of March 2023, and in the middle of April 2024, respectively. Furthermore, three peaks of D. suzukii adult flies were observed each year, whereas a total of six generations were predicted according to the accumulated degree-days. The male sex ratio of trapped D. suzukii was 1:0.32, 1:0.38, and 1:0.42 in 2022, 2023, and 2024, respectively. Raspberry fruit infestation reached a maximum of 76%, 75%, and 64% at the beginning of May 2022, middle of April 2023, and end of April 2024, respectively. Under the climate change scenario, knowledge of the eco-ethology of this insect and its population dynamics is essential for developing an IPM control strategy in Morocco, and further studies are ongoing to establish a biological and reasoned chemical approach based on degree-days.

Artificial intelligence (AI) and machine learning (ML) offer objective solutions in the elaboration of taxonomic keys, such as the processing of large numbers of samples, aiding in the species identification, and optimizing the time required for this process. We utilized ML to study the morphological data of eight species of Americabaetis Kluge 1992, a diverse genus in South American freshwater environments. Decision trees were employed, examining specimens from the Museu de Entomologia da Universidade Federal de Viçosa (UFVB/Brazil) and literature data. Eleven morphological traits of taxonomic importance from the literature, including frontal keel, shape of the mouthparts, and abdominal color pattern, were analyzed. The decision tree obtained with the Gini algorithm effectively differentiates eight species (40% of the known species), using only eight morphological characters. Our analysis revealed distinct groups within Americabaetis alphus Lugo-Ortiz and McCafferty 1996a, based on variations in abdominal tracheae pigmentation. This study introduces a novel approach, integrating AI techniques, biological collections, and literature data for aid in the Americabaetis species identification. It provides a valuable tool for taxonomic research on contemporary and extinct mayflies.

Soybean is a highly valuable commodity crop for Brazil's economy. However, it faces significant threats from the attack of a complex of lepidopteran pests, particularly Chrysodeixis includens (Walker) and Spodoptera frugiperda (J. E. Smith). These pests have been managed primarily using transgenic Bt soybeans, but limited knowledge exists about the resistance levels of Bt and non-Bt cultivars adapted to novel soybean-growing areas in Brazil, such as the Minas Gerais state. This study evaluated the resistance levels of Bt and non-Bt soybean cultivars to C. includens and S. frugiperda, and whether the Bt cultivars can differentially affect these pests across larval stages. No-choice bioassays were conducted using Bt (NS6010 IPRO and P97R50 IPRO) and non-Bt soybeans (UFLA 6301 RR, P96R90 RR, and ANsc 80111 RR) at V4-stage in the laboratory with neonate (24 h) and third-instar larvae. Larvae were fed leaf discs in Petri dishes, recording the mortality, leaf consumption, and weight gain after 7 days. There was high mortality of C. includens neonates on the Bt cultivars, but this trend was not observed for older larvae. For S. frugiperda neonates, there was high mortality on the Bt cultivar NS 6010 IPRO and non-Bt cultivar UFLA 6301 RR, but only the former was effective for older larvae. Although the Bt cultivars did not kill the third instars, antinutritional effects were found, such that leaf tissue consumed was not converted to larval weight gain. These findings are important for defining regional strategies of integrated and resistance management of C. includens and S. frugiperda in expanding regions of soybean cultivation in Brazil.

As a pest, the gall wasp Ophelimus migdanorum poses a risk to several Eucalyptus species in Colombia. In the tropical Andes, its biological development and the damage it causes can be influenced by climate, particularly rainfall. In this regard, we examined gall phenology, population fluctuation, and leaf damage caused by O. migdanorum, and its parasitoid Closterocerus chamaeleon, over 5 months at two sites with contrasting rainfall in peri-urban areas of Bogotá, Colombia. Gall phenology and foliar damage were assessed on 10 trees per site. We characterized gall phenology by assessing their size and color, wasps' developmental stages, as well as affected leaf area and gall density on the leaf blade. Additionally, the individuals found in five attraction traps at each site were quantified biweekly to record population fluctuations. The effect of rainfall on wasp frequency and gall density between sampling sites and dates was compared using the chi-square test, while the relationship with rainfall was evaluated using the Kruskal-Wallis test. Only females of the gall wasp and its parasitoid were observed during the study, displaying multivoltine behavior. Six developmental stages of the galls were differentiated, each characterized by distinct coloration. Drier microclimates favored gall size, wasps' development stage frequency, population trend, and foliar damage. The general trend indicated a greater abundance of the parasitoid C. chamaeleon compared to O. migdanorum. Our study suggests that O. migdanorum has a less damaging effect on E. globulus in areas with rainy microclimates.