Neotropical Entomology最新文献

Tympanoterpes merganota sp. nov. is described and illustrated. Notes on natural history and adult behavior are presented including the description of the acoustic repertoire. This new species is currently endemic to Brazil, occurring in shrublands in the Atlantic Forest and Pampa regions. Adults have been observed in association with Asteraceae shrubs, using these plants as calling, copula, and oviposition sites. These results were achieved with the contribution of citizen science, proving its importance as an auxiliary tool for researchers.

The aim of this study was to evaluate how climatic seasonality affects the defense mechanisms of plants and how this is reflected in the richness and abundance of different guilds of herbivorous insects, using the species Ipomoea carnea subs. fistulosa as a model. Herbivore collections were carried out over 12 months, during this same period the phenology and herbivory was monitored in 30 marked plants, in addition to the analysis of the herbivory index in the dry and rainy season, in addition to collection and analysis of soil nutrients. Phenology showed strong seasonality, showing pivot of leaves and fruits emission during the dry season, and the reproductive phases of emission of buds and flowers peaked in the rainy season. A total of 10,199 herbivores were registered, distributed in 6 orders, and in four guilds. The total abundance of herbivores was greater during the dry season and the richness was greater during the rainy season. As for herbivore guilds, the abundance of leaf chewers-crushers was higher during the dry season, while flower and bud chewers-crushers were more abundant in the rainy season, whereas the suckers showed greater wealth and abundance in the rainy season. The results show a strong influence of climatic seasonality on the phenological patterns of the plant species. However this influence is very conspicuous in Seasonally Dry Tropical Forests, therefore, there are several biotic and abiotic factors responsible for these results. Factors such as interspecific competition and the distribution of food resources at a certain time of the season, can act in conjunction with climatic factors to shape insect abundance patterns.

Thermal tolerance influences the survival, performance, and distribution of ectothermic organisms. Its effects are especially important given the advent of rapid climate change. While diet quality has been shown to modulate critical thermal maxima (CT_max) in ants under laboratory conditions, it remains unclear whether this response and the speed at which it appears are the same in wild ants. Here, we tested whether a carbohydrate-enriched diet could quickly increase CT_max in Dorymyrmex thoracicus, a heat-tolerant ant species in the Brazilian Caatinga. Using two field-based experiments, we found that ants given access to a 20% sucrose solution exhibited significantly higher CT_max values than did ants who did not have access to the sucrose solution. The second experiment showed that this difference appeared a few hours after the treatment, suggesting the operation of rapid physiological responses potentially linked to energy availability and heat shock protein synthesis. Thus, carbohydrate intake can immediately modulate thermal tolerance under natural conditions, a result that can help us predict how ants, and other ectotherms, may respond to climate-driven shifts in food availability and thermal stress.

The present paper describes a new species of Actinote Hübner, [1819] (Nymphalidae, Heliconiinae, Acraeini), Actinote palmarina Freitas, Magaldi, Kaminski & Paluch sp. nov., from northeastern Brazil, based on morphological and molecular data. Actinote palmarina sp. nov. is very localized, with only five individuals known from just two localities in the Brazilian states of Alagoas and Pernambuco. Larvae feed on Mikania hirsutissima DC. (Asteraceae) and larvae and pupae are distinct from the closely related Actinote melanisans Oberthür, 1917. This new species represents yet another case of butterfly endemism for the Northern Atlantic Forest. In addition, Actinote pellenea nordestina D Almeida, 1935 is here synonymized with Actinote pellenea auloeda Oberthür, 1917 ssp. rev.

Rhynchophorus ferrugineus (Coleoptera: Curculionidae), commonly known as the red palm weevil, is one of the most destructive invasive pests threatening palm species worldwide. Its rapid global spread has been facilitated by the international trade of infested plant material and its cryptic life cycle. In Brazil, a country with one of the highest palm species diversities and significant coconut production along its coastline, the introduction and establishment of R. ferrugineus pose a serious threat to native biodiversity and the agricultural economy. In this study, we used the MaxEnt modeling approach to predict the potential distribution of R. ferrugineus in Brazil, based on 79 occurrence records and nine selected bioclimatic variables. The consensus model exhibited excellent predictive performance (AUC = 0.95, TSS = 0.84). Our results indicate that coastal areas of the Northeast, Southeast, and South regions present high environmental suitability for the species, with low uncertainty, while portions of the Amazon show moderate suitability coupled with higher uncertainty. The mean temperature of the driest quarter (BIO9) was identified as the most influential variable, aligning with the species' thermal preferences. The presence of highly suitable areas overlapping regions of dense palm diversity and economically important crops underscores the urgent need for early detection and integrated management strategies. Our findings provide critical insights for biosecurity planning and highlight Brazil's vulnerability to R. ferrugineus invasion.

Animal identification is pivotal for ecological studies, yet automated recognition tools for bee species remain underexplored. Here, we present a machine learning approach using a Random Forest algorithm to identify five bee species representing three phylogenetically diverse families within Apoidea based on their flight and floral buzz sounds. Acoustic parameters were extracted from recordings, with the fundamental frequency emerging as the most relevant feature for species classification. Machine learning models achieved 90.94% using flight buzz and 82.22% with floral buzz. Combining both sound types increased accuracy to 95.04%. Among all bee species, B. pauloensis showed the lowest classification performance, likely due to intraspecific variation in body size, leading to acoustic overlap with other species. Despite this, the proposed method demonstrates high performance and suggests that acoustic features can be reliably used for species-level identification. This approach holds potential for non-invasive monitoring of bee richness and abundance in diverse communities, contributing to the development of automated tools for ecological research and biodiversity assessment.

The carambola fruit fly (Bactrocera carambolae Drew & Hancock) is a quarantine pest that poses a threat to Brazilian fruit production and export. In September 2023, the pest was recorded for the first time in the municipality of Oriximiná, in the state of Pará. Control methods were implemented by the Agricultural Defense Agency of Pará, in coordination with the Ministry of Agriculture and Livestock, aiming at eradicating the pest. This study aimed to evaluate the effectiveness of phytosanitary measures in reducing the population of the carambola fruit fly under the climatic conditions of Oriximiná, Pará, Eastern Amazon, Brazil. Monitoring took place from September 12 to November 15, 2023, in a 182 hectare urban wooded area. A total of 317 specimens were captured, including 274 males and 43 females, with higher captures in Jackson type traps (67.5%) compared to McPhail type traps (32.5%). The fruiting phase was observed in 93.1% of the fruit trees where traps were installed. Relative humidity, solar radiation, and rainfall influenced the pest's population fluctuation, which was also associated with the collection of 1059 kg of fruit. A dissimilarity was observed between trapping density and pest incidence in traps, with a movement radius of 3.3 km, low spatial dependence [Moran's Index of 0.092 (p > 0.05)], low capture rates in the largest trapping coverage area, and greater abundance in areas with high boat traffic along the Amazon River in Pará. The maximum fly/trap/day index of 0.54 highlights the effectiveness of control efforts and underscores the importance of the eradication program's actions in containing the territorial spread of B. carambolae in the Eastern Amazon and ensuring the sustainability of the national fruit production chain. .

Insect pest infestations in pasture areas have a detrimental impact on Brazilian livestock. One of the challenges currently faced by livestock farmers is the control of pests such as chinch bugs of the genus Blissus (Hemiptera: Blissidae), an emerging pest of pastures in Brazil. There is a significant gap in the literature on this group of insects. The first step in developing management tools for this pest involves establishing a mass-rearing protocol that enables individuals to be reared in sufficient numbers for subsequent studies. In this study, we present a protocol for the mass rearing of Blissus pulchellus Montadon (Hemiptera: Blissidae) in an indoor cultivation system, including the environmental conditions necessary for the growth of the evaluated host grasses (Urochloa humidicola cv. Humidicola, Urochloa ruziziensis cv. Ruziziensis, Urochloa humidicola cv. Llanero, and Urochloa brizantha cv. Marandu) along with the chinch bug B. pulchellus. Mass rearing of B. pulchellus during indoor cultivation was possible. Both host grasses and B. pulchellus developed adequately at 30 ± 2°C and variable photoperiods ranging from 16:8 to 14:10 light:dark. Urochloa humidicola cv. Humidicola and Urochloa ruziziensis cv. Ruziziensis enhanced the population growth of insects, enabling the collection of up to 2000 insects per tray per week. This study presents the first successful mass-rearing method for chinch bugs, Blissus sp., in an indoor cultivation system for use in different studies.

Insect pests in stor ed products cause qualitative and quantitative losses in seed lots, reducing their commercial value by directly compromising the physiological and sanitary quality of the seeds. The objective of this study was to evaluate the physiological quality and perform a proximate analysis of rice seeds infested with Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), using radiographic images. The X-ray analysis was used to detect and identify the weevil development stages and quantify the percentage of infestation in rice seeds. The physiological quality and the proximate analysis were evaluated after the seeds were subjected to four levels of infestation by S. zeamais: 0%, 2%, 3%, and 5%. The radiographic images enabled efficient detection of infestation levels, identification of the weevil's developmental stages, and assessment of damaged and empty seeds. The following physiological tests were performed: germination test, first germination count test, emergency test, retention capacity of the substrate, emergency speed index, and electrical conductivity test. For the physiological and proximate analysis, the experimental design was completely randomized, with four treatments and four replications. Statistical differences were observed in physiological assessments and proximate analysis across infestation levels, confirming that infestation intensity directly affects seed viability and nutritional value. This emphasizes the importance of effective monitoring methods to mitigate pest damage to stored seeds.

The flood mosquito Aedes albifasciatus adapts to the thermal conditions of different regions and presents demographic explosions, causing problems for livestock farming and public health, including outbreaks of western equine encephalitis. Between October 2019 and June 2021, their larval development was monitored in Tandil temporary pools, recording 35 events. For each one, the larval development time and the average daily mean temperatures were calculated. The data were fitted to several temperature-dependent bibliography nonlinear models for insects, previously setting the lower and upper thermal development thresholds (for Ae. albifasciatus in the studied region) at 7.62°C and 33°C, respectively. A new model, based on combinations of factors present in bibliography models, is proposed to estimate the larval development rate as a function of temperature. The models were validated using the root mean square error (RMSE) and concordance index (d). In addition, the distribution of percentage frequencies of the difference between the length of the period estimated by the models and that recorded in the field was calculated. The best model had the highest agreement index (0.9), the lowest RMSE (0.01), and the highest agreement between the estimated and observed development rate (83%). This model could be useful as a pre-diction tool of Ae. albifasciatus abundance peaks in the context of future outbreaks of western equine encephalitis in South America.