Resumo em Inglês:

ABSTRACT Understanding the population dynamics of the corn leafhopper Dalbulus maidis (Hemiptera: Cicadellidae), the vector of pathogens responsible for maize stunt diseases, is essential for establishing an integrated management program for this pest. Defining an easy, fast, accurate and representative sampling method for D. maidis would allow both population estimation for monitoring and control decision making. Therefore, we evaluated three sampling methods (yellow sticky traps, direct whorl counts and sweep nets), time of day and variations in climatic factors on D. maidis captures. For this purpose, D. maidis populations in field maize plants at phenological stages V3 to V9 were monitored from September 2022 to May 2024. The numbers of leafhoppers captured by the three sampling methods were correlated with climatic variations during this period. The sampling method affected the number of individuals collected. During the sampling period, 11,520 D. maidis individuals were captured. Among these, yellow sticky traps recorded 957 individuals. Direct whorl counts registered 2,999 individuals in the morning and 2,723 in the afternoon. Sweep net sampling recorded 2,415 individuals collected in the morning and 2,426 in the afternoon. Direct whorl observations showed positive correlations with temperature, relative humidity and accumulated rainfall. The results show that the active direct whorl counting method is the most efficient for monitoring and observing population variations of the corn leafhopper, outperforming sweep nets and yellow sticky traps. This study highlights the importance of adjusting monitoring strategies for more accurate population estimates and control recommendations in integrated management programs for the corn leafhopper D. maidis.

Resumo em Inglês:

ABSTRACT Cockroaches are recognized as important mechanical vectors of antimicrobial-resistant bacteria in urban environments. This study examined the diversity of cockroach species, seasonal abundance, and associated bacteria across four urban biotopes, i.e., households, warehouses, hospitals, and canteens. We hypothesized that cockroach diversity and bacterial resistance profiles would differ significantly by sub-division, season, and habitat type, reflecting environmental and anthropogenic influences. Sampling was conducted by handpicking and using baited traps. Bacteria from the gut and surface were characterized using morphological, biochemical, and 16S rRNA sequencing. Resistance was tested using the Kirby–Bauer disk diffusion method against eight antibiotics, including azithromycin, ciprofloxacin, levofloxacin, cefixime, ceftriaxone, amoxicillin, tetracycline, and cefaclor. Four cockroach species were recorded; Blattella germanica and Periplaneta americana were the most widespread, while Pycnoscelus surinamensis occurred only in Wazirabad. Households showed the highest diversity (Simpson’s 1–D = 0.573; Shannon’s H = 0.939), and summer had the greatest richness and diversity (1–D = 0.565; H = 0.919), whereas winter had the lowest. Cefixime resistance was the highest (90%), while ciprofloxacin and levofloxacin had the lowest (5%). Multidrug resistance occurred in 35% of strains, 60% were resistant to at least one antibiotic class, and one strain was pan-susceptible. Seventeen of twenty strains (85%) had a Multiple Antibiotic Resistance (MAR) index >0.2, indicating a significant public health risk. The seasonal and habitat-related variations in both cockroach abundance and bacterial resistance patterns underscore their role in the spread of multidrug resistant bacteria. Integrated pest management and targeted antibiotic stewardship are essential to mitigate this emerging urban health threat.

Resumo em Inglês:

ABSTRACT The sorghum aphid Melanaphis sorghi (Hemiptera: Aphididae) has become the primary threat to crop production in various parts of the world. Although the combined use of organosynthetic insecticides and resistant hybrids is a common strategy in countries like the USA, Brazilian farmers face the challenge of a lack of registered active ingredients and resistant cultivars against M. sorghi. This study aimed to evaluate grain sorghum genotypes for resistance to M. sorghi infestation. In the initial screening phase, 28 genotypes were evaluated, from which eight were selected and grouped as: i) resistant to M. sorghi (BRS373, CMSXS3017, BRS310, and SC110 [control]); and ii) susceptible (CMSXS3012, 1822043, 2116017, and AG 1085), for further assessment and determination of productivity in subsequent stages. The trial was conducted in a greenhouse under controlled humidity and temperature, with three controlled artificial infestations and injury assessments every seven days. Aphid infestation primarily reduced the plant fresh weight of the plant and grain size, negatively affecting grain weight per panicle. Without M. sorghi infestation, the hybrid genotypes AG 1085, 1822043, and CMSXS3012 showed the highest grain weight; however, they were susceptible to aphids when infested. Under infestation, the most resistant genotypes with the highest grain weight values were CMSXS3017, SC110, BRS373, and BRS310. The SC110 lineage was minimally affected by aphid infestation and should be used as a source of resistance in breeding programs for aphid tolerance. The results of this study may be used to evaluate productivity losses due to sorghum aphid infestation and to propose potential resistant genetic materials. Combined with other integrated management tactics, these findings can make sorghum aphid control more precise and sustainable.

Resumo em Inglês:

ABSTRACT Strumigenys is a pantropical distributed ant genus, consisting mostly of leaf-litter inhabitants. In the Neotropical region, species are most abundant in rainforests, but they are also found in mesic habitats. We provide additions to the taxonomy of Neotropical Strumigenys, along with terminological and etymological considerations for the genus. Six species new to science, with ranges within the Brazilian territory, are described: S. aline sp. nov., S. carol sp. nov., S. jaqueline sp. nov., S. mboehara sp. nov., S. paloma sp. nov., and S. vitoria sp. nov. All newly described species exhibit clear morphological affinities with other Neotropical taxa assigned to well-defined species groups. Illustrated identification keys are provided for all species within the designated Neotropical species groups. We also provide a table of the aligned terms containing lexical pairs, their corresponding pair schema, the RCC-5 articulation defined for the alignment, the respective preferred term, and the criteria used to define it.

Resumo em Inglês:

ABSTRACT Tribolium castaneum is ubiquitous storage pest of wheat. In this study screening of ten certified wheat varieties namely Aas 11, Bahawalpur 2000, Fareed 06, Ghazi 19, Gold 16, Johar 16, Manthar 03, Nawab 21, Punjnad 01 and Sadiq 21 was done against T. castaneum attack. Results showed maximum numbers of damaged grains were 45.000 ± 3.605 in variety Nawab 21 and 44.000 ± 1.732 in Gold 16 while significantly least damaged grains were 13.667 ± 1.764 in variety Bahawalpur 2000 and 15.667 ± 2.404 in Punjnad 01. Percent weight loss was computed maximum 1.654 ± 0.557% in variety Gold 16 while significantly least percent weight loss was .376 ± 0.264% in variety Bahawalpur 2000 and .498 ± 0.248% in Punjnad 01. However, percent weight loss was .715 ± 0.123% in variety Nawab 21 significantly at par with variety Punjnad 01. Germination of attacked seeds showed maximum germination 84.000 ± 0.000% in Bahawalpur 2000 followed by 82.667 ± 2.667% in Manthar 03, 82.667 ± 5.812% in Ghazi 19 in descending order. Significantly least germination 57.333 ± 9.333% was in AAS 11, 61.333 ± 5.812% in Nawab 21 and 68.000 ± 0.000% in Gold 16 in ascending order. Regression analysis showed significant effect of T. castaneum damage on germination percentage of infested seeds. Therefore, to successfully manage T. castaneum in storage these data suggest the integration of less susceptible wheat varieties with other control tactics for example Bahawalpur 2000 in this case.

Resumo em Inglês:

ABSTRACT Although thrips are among the most abundant insects on mangaba (Hancornia speciosa) leaves, there is no information on population fluctuation. Additionally, the known species richness refers to the lower layer of the mangaba tree canopy, which may underestimate thrips populations because they may not be uniformly distributed throughout the plant. This study aimed to assess species richness and population fluctuation of thrips species in H. speciosa varieties, considering the insects’ vertical distribution across the lower, middle, and upper canopy strata over two years. The study was conducted between 2018 and 2019 with the native species collection from the School of Agronomy of the Federal University of Goiás, in Goiânia, Goiás state, Brazil. In each collection, 12 plants per variety were evaluated. Sampling was performed at three canopy heights, with two branches per height and 10 leaves per branch. A total of 12,197 thrips were found, with phytophagous species predominating (Coremothrips nubilicus, Heliothrips angustior, Paraleucothrips sp. and Rhamphothrips sp.). Population peaks were recorded in October, the beginning of the rainy season. Thrips were similarly distributed across the mangaba plant, except for Heliothrips angustior, which has a higher abundance in the lower stratum. This study marks the first record of the species Scolothrips asura, Frankliniella fulvipes, Trybomia gossypii, and Adraneothrips alternatus in H. speciosa, and the first report of S. asura in Brazil.

Resumo em Inglês:

ABSTRACT In this study, we revisited the taxonomy of three southern endemic Brazilian species of alderflies of the genus Ilyobius Enderlein, 1910. Our investigation was based on specimens of Ilyobius nubilus (Navás, 1933) collected from a recently discovered population from state of Paraná, which is the first record of the family Sialidae for that state. The specific limits between Protosialis nubila Navás, 1933, P. brasiliensis Navás, 1936 and P. hauseri Contreras-Ramos et al., 2005—all now combined in Ilyobius—were evaluated based on a comparative morphological study. In light to the new data, we judge Protosialis brasiliensis and P. nubila represent the same species, and therefore, Protosialis brasiliensis is reinstated as a junior synonym of P. nubila with Ilyobius nubilus (Navás, 1933) the valid name to be applied to this species. A reviewed diagnosis for I. nubilus, including a key to Brazilian species of the genus are presented and the specific status of I. hauseri is also discussed.

Resumo em Inglês:

ABSTRACT The genus Ranatra Fabricius, 1790 is currently represented in Vietnam by nine previously recorded species. Based on specimens collected from Vietnam and detailed morphological examinations, a new species, Ranatra uminhensis sp. nov. (belonging to the Ranatra malayana group), is described, illustrated, and discussed. Additional morphological data for Ranatra varipes Stål, 1861 are provided, and DNA barcode (COI) sequences for both species are presented for future reference.

Resumo em Inglês:

ABSTRACT This is the first study of the ultrastructure of sensilla on the antennae and palpus of mycophagous midges in the worldwide subfamily Lestremiinae. It is also the first study of palpal sensilla in the family Cecidomyiidae. We characterized fourteen subtypes within seven types of antennal sensilla and three types of palpal sensilla within this group. We compared these findings with those in the literature for other Diptera families and the Cecidomyiinae subfamily. We discovered and characterized a novel, previously unreported type of antennal sensilla, as well as a new subtype of coeloconica sensilla. Additionally, we report styloconica and styliform sensilla for the first time in the family. To standardize terminology, we correlate traditional morphological terminology with the nomenclature used in ultrastructure studies and propose a unified naming system. The morphological characters described and discussed in this study are essential for understanding the relationships among Lestremiinae taxa, as well as the evolution of early Cecidomyiidae lineages.

Resumo em Inglês:

ABSTRACT The subgenus Canthon (Trichocanthon) Pereira and Martínez, 1959 is revised and currently comprises a single valid species, Canthon (Trichocanthon) sordidus Harold, 1868. An updated geographic distribution is provided, revealing his endemism to the northeastern Amazon rainforest. A lectotype is designated for the name, and a refined morphological redescription of the species is provided, including the first detailed illustrations of the male tegmen and endophallites. By integrating an exhaustive literature review with new morphological data, we provide characters useful for future cladistic analyses, as well as ecological information for conservation assessments of dung beetle assemblages in the Amazon.