Neotropical Entomology最新文献

Feeding by mayflies is influenced by resource availability, and their feeding preferences can vary acrossdevelopment stages. Studies assessing food preferences can therefore provide insights into the functional role of a species. The aim of this study was to evaluate the feeding preferences of Americabaetis alphus nymphs on periphyton growing two different substrates and two sizes of particulate organic matter. Experimental units were composed of acrylic and stainless steel substrates; the control contained no nymphs. The substrate preference was determined by the presence or absence of nymphs on the substrates. Bacterial density and chlorophyll-a concentration were measured to evaluate food intake, and the frequency of microbial taxa adhering to the substrates was calculated. Salix humboldtiana leaves were processed into two categories, fine particulate organic matter (FPOM) and coarse particulate organic matter (CPOM). In each experimental unit, 25 mg of FPOM and 25 mg of CPOM were provided. Food intake was estimated by the difference between the initial and final weights of FPOM and CPOM. The highest bacterial and chlorophyll-a intake was observed on the stainless steel substrates. The taxonomic composition differed between the substrates, with stainless steel showing a higher frequency of diatoms. In the second experiment, the weights of FPOM and CPOM were reduced after the feeding period, with a greater reduction observed in FPOM. It is important to evaluate resource preferences in a combined manner, as well as to assess other Baetidae species, given the scarcity of information on the topic for the family.

There are still many gaps in knowledge about how different preservative solutions can guarantee sufficient DNA recovery for the taxonomic determination of flies of forensic importance. In the present study, we evaluated the recovery and amplification rates of mitochondrial DNA from larvae of the forensically important blow fly Chrysomya megacephala (F.) (Diptera, Calliphoridae), preserved for up to 47 days in the solutions commonly used in routine forensic investigations. Some larvae (N = 88) were immediately placed in the preservative solution, while another group of larvae (N = 88) was killed by immersion in water heated up to 80 °C for 30 s before being preserved at room temperature. In general, it was possible to recover highly pure DNA from larvae subjected to almost all treatments, with yields varying proportionally across different storage intervals. Among the solutions that yielded the highest DNA and consequently achieved successful amplification rates were 99.3% ethanol (> 100 ng/µL, with rates of 95%) and 70% ethanol (20-100 ng/µL, with rates of 90%), primarily up to the 28-day storage interval. The worst DNA yields and low amplification rates (approximately 50%) were associated with the 47-day storage interval, despite the preservative method used, except for Kahle's solution, which presents no amplification at all. Our results suggest that ethanol at concentrations of 70-99.3% is the most efficient preservative for preserving the integrity and usability of forensically important larvae DNA for diagnostic purposes, particularly within a range of up to 28 days.

We report the first records in Brazil of Diocalandra frumenti (Fabricius) and Polytus mellerborgii (Boheman), weevil species of potential phytosanitary concern. These detections were made through surveys in the Entomological Collection of the Universidade Federal Rural de Pernambuco (CERPE) and targeted field inspections in northeast Brazil. These findings expand the known distribution of these weevils in Brazil and underscore the need for enhanced phytosanitary surveillance due to their potential impact on crop production in other countries and the implications for quarantine regulations.

Honey bees (Apis mellifera Linnaeus) are important pollinators in natural and agricultural ecosystems and play a key role in global food production. However, colonies are increasingly affected by multiple stressors, including emerging parasites, which can compromise their health and performance. Among these, phorid flies (Diptera: Phoridae) have been observed in association with weak or collapsing honey bee colonies in various regions in Mexico, yet their effects on honey bee behavior and immune function under field conditions remain poorly understood. In this study, we investigated the impact of a phorid fly infestation on the behavior, survival, and immune defense of A. mellifera under natural conditions. Using radio-frequency identification (RFID) technology, we monitored the daily activity of individually tagged bees from a healthy hive and a naturally infested hive. Additionally, we assessed the prevalence of coinfections and measured immune responses including prophenoloxidase (proPO), phenoloxidase (PO), lytic activity, and hemocyte counts. Our results showed that phorid fly infestation was associated with a reduction in the frequency and duration of foraging trips, nocturnal activity, and significant changes in immune function, particularly elevated proPO/PO activity and reduced total hemocyte counts. No significant differences were observed between adult and pupal stages in immune parameters, suggesting a consistent physiological response across developmental stages. While only one hive was infested and ultimately collapsed, these findings provide evidence that phorid flies can disrupt key behavioral and immune processes in honey bees. Further studies are needed to determine the broader implications of phorid infestations for colony health and resilience.

The fall aِrmyworm, Spodoptera frugiperda (J.E. Smith), causes significant yield losses due to its high fecundity, broad host range, defoliation capability, and voracious larval feeding. Biological control using microorganisms has gained attention as a sustainable alternative to chemical pest management. Entomopathogenic fungi employ distinct modes of action and produce secondary metabolites with insecticidal properties. This study aimed to isolate and identify indigenous entomopathogenic fungal species and evaluate their pathogenicity against S. frugiperda. Three isolates belonging to the division Ascomycota were recovered from soil samples and identified as Botryotrichum domesticum isolate MP3H-5, Albifimbria verrucaria isolate E16, and Purpureocillium lilacinum isolate WARSO2 6 8. When applied at a concentration of 1 × 10⁹ conidia mL⁻¹, the fungal isolates induced significant cumulative mortality (60 to 84.44%) in S. frugiperda larvae at 14 days post-treatment. Albifimbria verrucaria was the most virulent, exhibiting the lowest LC₅₀ (2 × 10⁷ conidia mL⁻¹) and LT₅₀ (0.46 days). At a lower concentration of 1 × 10⁷ conidia mL⁻¹, the P. lilacinum isolate caused the highest pupal mortality (80%) at 7 days post-treatment. Crude fungal metabolites also demonstrated larvicidal activity, resulting in cumulative mortality rates of up to 50%. Furthermore, larvae treated with the entomopathogenic fungi showed elevated catalase activity. The high toxicity observed is likely associated with fungal secondary metabolites, which were characterized using GC-MS analysis. Under laboratory conditions, the tested entomopathogenic fungal isolates demonstrated strong potential as microbial agents for the control of S. frugiperda. However, further field-based validation is necessary to confirm their efficacy.

Coffee berry borer, Hypothenemus hampei Ferrari (Coleoptera: Curculionidae), is the most damaging pest of coffee worldwide, reducing both yields and quality. African parasitoid wasps have been widely released in Colombia as biological control agents for H. hampei, yet their establishment has been inconsistent, partly due to limited information on how temperature affects their performance. We evaluated the thermal biology of two key parasitoids of H. hampei: the larval-pupal ectoparasitoid Prorops nasuta Waterston (Hymenoptera: Bethylidae) and the adult endoparasitoid Phymastichus coffea LaSalle (Hymenoptera: Eulophidae). Using age-stage, two-sex life tables across eight constant temperatures, we quantified temperature effects on development, survival, fecundity, and population growth. We identified 22-25 °C as the optimal range for survival, and fecundity peaked at 25 °C. Life-table parameters indicate maximal population growth at 25 °C for both parasitoids. Development failed at extreme temperatures (32 and 35 °C), highlighting upper thermal limits relevant to mass-rearing and field releases for both parasitoids. Degree-day models were developed to estimate the potential number of generations across Colombian coffee-growing regions. We predict 5.5-11.6 annual generations of P. nasuta and 2.2-8.6 of P. coffea, depending on local temperature regimes. These results identify optimal temperature ranges for rearing and deploying P. nasuta and P. coffea and provide spatially relevant predications for their establishment potential in Colombian coffee-growing regions. Regions with mean temperatures between 22 and 28 °C are expected to support the greatest efficacy of augmentative biological control programs targeting the coffee berry borer.

Rising ambient temperatures driven by global warming are subjecting insect populations to thermal conditions exceeding their historical environmental ranges. Understanding how temperature alters key life-history traits is essential for optimizing integrated pest management strategies, particularly for invasive species. This study investigated the effects of short-term thermal stress (31 °C for the parental generation, with offspring returned to 26℃) on life history traits and insecticide sensitivity in the codling moth Cydia pomonella (L.), a major agricultural invasive pest. Results demonstrated that elevated temperature significantly shortened larval developmental duration and reduced pupal weight and overall fitness, with these phenotypic effects persisting across generations. Additionally, increased temperature attenuated the sensitivity of C. pomonella to lambda-cyhalothrin, especially in parental generation. In contrast, reproductive output and sensitivity to chlorantraniliprole remained largely unaffected by thermal elevation. Activities of detoxification enzymes including cytochrome P450 monooxygenases (P450s), carboxylesterases (CarEs), and the antioxidant enzyme catalase (CAT), were significantly upregulated at elevated temperatures, with transgenerational inheritance observed in progeny, potentially contributing to the observed decrease in insecticide sensitivity. These findings advance our understanding of the transgenerational physiological and biochemical adaptions of C. pomonella to thermal stress, with implications for resistance management under climate change scenarios.

Insect gut bacterial communities are significantly influenced by host plants. Tuta absoluta (T. absoluta), an invasive pest that damages tomato, eggplant, and potato plants of the Solanaceae family, causes significant economic losses. This study investigated the effect of different host plants on the composition and functionality of the gut bacterial community of T. absoluta. The gut bacterial community of T. absoluta fed on different host plants was investigated using high-throughput sequencing. Our results showed that the host plant significantly influenced the gut bacterial diversity. At the phylum level, Proteobacteria and Cyanobacteria consistently dominated the gut microbiota of T. absoluta larvae regardless of host plant species. Regarding genus-level composition, Wolbachia was the predominant genus in larvae fed tomato and potato, whereas Enterobacter prevailed in those reared on eggplant. Functional prediction analysis identified several enriched pathways, predominantly related to metabolism. These included enzyme families, biosynthesis of other secondary metabolites, metabolism of other amino acids, xenobiotics biodegradation and metabolism, carbohydrate metabolism, and glycan biosynthesis and metabolism. This study revealed significant variations in the community structures of gut microbiota in T. absoluta feeding on different host plants. These findings will improve our understanding of the gut microbiota of T. absoluta and its potential interactions with the host insect, thereby facilitating the development of microbial-based pest management strategies.

The Sphingidae family of moths plays a vital role as pollinators; however, research focusing on certain genera within the family remains limited. This study adopted an integrative approach, drawing on literature, the SiBBr, GBIF, and SpeciesLink databases, and field collections to examine the distribution of Eumorpha Hübner, 1807 species across Brazil. A total of thirteen species is known to occur in the country, yet substantial knowledge gaps remain regarding their actual distribution. We compiled 623 occurrence records representing 14 species. Most species and occurrence records were concentrated in the Atlantic Forest and Amazon biomes. The results indicate that research directly focused on Eumorpha remains scarce and that, despite advances in the digitization of national collections, the number of related publications has not increased. This study provided important insights into the distribution of Eumorpha, showing that some species, such as Eumorpha vitis (Linnaeus) and Eumorpha fasciatus (Sulzer), have a wide distribution, while others, like Eumorpha translineatus (Rothschild), appear more restricted. In addition to contributing to the understanding of Eumorpha distribution in Brazil, the study also highlights the relevance of combining multiple data sources to address existing knowledge gaps.

This study examines the aphid fauna associated with Caryophyllaceae in Iran, combining new field collections with previously published records. In total, 25 aphid species, along with two unidentified species across eight genera, were documented on 24 Caryophyllaceae host species. We describe Aphidura madari sp. nov., based on both apterous and alate viviparous females collected from Silene gaubae, Silene stapfii, and Silene sp. Additionally, we redescribe the apterous and alate forms of Aphidura gallica Nieto Nafría, Mier Durante & Remaudière, 2013, a new record for the aphid fauna of Iran, using new material from Iran. Examination of historical specimens also revealed that record of A. gypsophilae in Iran was misidentification of A. picta, and A. togaica should now be regarded as an uncertain record for the country. A total of 61 aphid-host plant associations were identified, including 18 new global records and four new records for Iran. The genera Aphidura (10 species) and Myzus (5 species) exhibited the highest diversity on Caryophyllaceae hosts. Several unusual aphid-host associations were also recorded, such as Acyrthosiphon pisum on Acanthophyllum bracteatum, Aphis solanella on Silene conoidea, and Sitobion avenae on Dianthus caryophyllus; these may represent fortuitous collections or possible host shifts influenced by environmental factors. This work also offers modifications to existing keys in Aphids on the World's Plants and provides an identification key for aphids associated with Caryophyllaceae in Iran.