The eggs parasitoids Myartsevaia chrysopae (Crawford) (Hymenoptera: Encyrtidae), Telenomus lobatus Johnson, Telenomus tridentatus Johnson (Hymenoptera: Scelionidae) and Trichogramma atopovirilia Oatman and Platner (Hymenoptera: Trichogrammatidae) are reported for the first time or in new localities in Mexico. Their occurrence was first discovered in 2018 during a survey of parasitism on chrysopid eggs, conducted on Sorghum bicolor L. Moench (Poales: Poaceae) and Zea mays L. (Poales: Poaceae) in different locations in Sinaloa, Mexico. The identity of the parasitoids was determined by morphology and for both species of Telenomus the barcode region of the cytochrome oxidase 1 gene (CO1) was generated to facilitate molecular diagnosis of these species in future studies.

Bacterial symbionts play an important role in insect survival by contributing to key metabolic and defensive functions. While stingless bees are known to harbor diverse microbial communities, their core bacterial symbionts remain poorly characterized. In this study, we analyzed the gut microbiota of sixteen stingless bee species collected from different regions of Mexico using 16S rRNA gene sequencing on the Illumina^® MiSeq™ platform. Our results revealed that Proteobacteria, Firmicutes, and Actinobacteria are the most abundant bacterial phyla across species. Among the dominant genera, lactic acid bacteria, such as Lactobacillus spp., Bifidobacterium, and Fructobacillus spp., were the most prevalent. These bacteria are responsible for developing biochemical functions in metabolic processes like lactic fermentation and the biotransformation of complex organic compounds into molecules that are more easily assimilated by bees. This study offers a novel perspective on the diversity and predicted composition of gut microbiota in Mexican stingless bees. By highlighting differences in microbial communities among species with different feeding habits, our results emphasize the importance of preserving microbial biodiversity in these pollinators.

Bacterial symbionts in insects constitute a key factor for the survival of the host due to the benefits they provide. Parasitoid wasps are closely associated with viruses, bacteria, and fungi. However, the primary symbionts and their functions are not yet known. This study was undertaken to determine the gut microbiota of six species of the Telenomus genus: T. alecto (Crawford), T. sulculus Johnson, T. fariai Costa Lima, T. remus Nixon, T. podisi Ashmead, and T. lobatus Johnson & Bin. Wasp parasitoids were collected from their hosts in different locations in Mexico. DNA was extracted from gut collection, and sequencing of bacterial 16S rRNA was carried out in Illumina^® MiSeq™. Among the six species of wasps, results showed that the most abundant phylum were Proteobacteria (82.3%), Actinobacteria (8.1%), and Firmicutes (7.8%). The most important genera were Delftia and Enterobacter. Seventeen bacteria species were found to be shared among the six species of wasps. The associate microbiota will help to understand the physiology of Telenomus to promote the use of these wasp parasitoids in the management of insect pests and as potential biomarkers to target new strategies to control pests.

The Aedes aegypti (Linnaeus 1762) mosquito is the most important vector transmitting dengue virus and other pathogens in Latin America. There are several control programs, many of which are ineffective, and therefore, new control alternatives need to be developed. Small interference RNAs (dsiRNA) are mediators of the interference of gene expression. Silencing RNA is a very conserved mechanism in nature in which small double-stranded siRNA (dsiRNA) regulates gene translation. The aim of this study was to use antisense RNA (dsiRNA and siRNA) by oral administration in stage-I mosquito larvae and evaluate the effect of inhibition of the translation of exon 5 of gene DSX. The exon is removed specifically in males (alternative splicing in exon 5 encodes a protein version of females in dipteran species). The dsiRNA molecule had greater impact on individuals treated, obtaining 25.45% of emerged females, in contrast to the siRNA molecule that had 35.80%, compared with the check in which the emergence ratio was 1:1. This might have been due to the chemical structure of the molecule, because dsiRNA is folded on itself, providing greater stability, compared to single-chain siRNA. Silencing with iRNA of exon 5 in the DSX gene produced changes in sexual differentiation of Ae. aegypti, which could lead to a new mosquito control strategy.

Introducción. La enfermedad de Chagas es endémica en Latinoamérica y es causada por el parásito Trypanosoma cruzi. Los vectores son chinches de la subfamilia Triatominae. En México, se han identificado unas 31 especies y en Nuevo León existen seis especies en 23 de los 51 municipios del estado. Objetivo. El objetivo del presente estudio fue documentar nuevos registros de triatominos en el municipio de General Zuazua, Nuevo León. Materiales y métodos. La colecta de triatominos se realizó en una zona semi-urbana del municipio de General Zuazua, Nuevo León. En dos puntos de colecta separados por 150 m, se colocaron trampas tipo pantalla blancas de 1.5 x 1.5 m, iluminadas con luces blancas LED en horario de 1800 a 0700 h. Se registraron variables ambientales como temperatura del aire, temperatura del suelo, velocidad del aire, humedad relativa en cada sitio usando un termo-anemómetro. Los especímenes colectados fueron resguardados en recipientes de plástico de 30 ml de capacidad al cual se le añadió papel filtro circular en la base y una tira de papel filtro arreglado de forma acordeón. La chinche Paratriatoma lecticularia fue mantenida viva en el laboratorio y fue alimentada dos veces con sangre de ratón y las heces fueron examinadas para la búsqueda de tripromastigote metacíclico de Trypanosoma cruzi. Resultados. Se capturaron dos especies de triatominos Paratriatoma lecticularia y Triatoma gerstaeckeri. Conclusión. Ambas especies son nuevos registros para el municipio de General Zuazua, Nuevo León.

Journal of the New York Entomological Society