Distribution of red imported fire ants, Solenopsis invicta Buren, across West Texas was surveyed during the fall of eight consecutive years, 2013-2020. Forty-six counties were surveyed from the Panhandle in the north to the Mexican border. During the 2019 and 2020 surveys, S. invicta was collected in 17 and 16 counties, respectively, beyond the quarantine line. This was more positive collections than during any previous survey year. In 2019, the survey included 10 counties where S. invicta had never been recorded (Andrews, Borden, Briscoe, Childress, Collingsworth, Hansford, Loving, Pecos, Reeves, and Zapata), and an additional two counties (Hutchinson and Lipscomb) were added in 2020. The accumulated data provided evidence that S. invicta continues to expand westward.

Indiscriminate use of insecticides to control vector-borne disease contaminates the environment and with time, mosquitoes gradually become resistant, making their control increasingly difficult. An alternative to synthetic insecticides, such as use of essential oils and extracts from plants, is needed for vector control. This study aimed to evaluate Cuban essential oil of Citrus aurantium (Sapindales: Rutaceae) against Aedes aegypti L. mosquito (Diptera: Culicidae), the main vector of arbovirus in Cuban. Calculated mean lethal concentrations (LC) were significantly low (LC₅₀ = 13.5 mg/liter (Rockefeller) and 15.5 mg/liter (Marianao 2013). A developmental inhibitory effect was obtained by exposing each population of mosquito larvae to lethal concentration LC₉₀. The emergence of adult mosquitoes was inhibited by exposing larvae to the LC₉₀ of each population. Neither adulticidal activity was obtained with papers and bottles impregnated at neither 60 mg/ml nor, repellent activity with the evaluated formulations. C. aurantium oil is a promissory candidate for control larvae of Ae. aegypti, although it was not effective against adults nor repellent unless formulations were enhanced.

Essential oils are plant compounds produced as secondary metabolites with toxic activity against some insect pests. Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) is widely distributed and recently caused phytosanitary contingency in maize (Zea mays L.) and sorghum (Sorghum bicolor (L.) Moench) in Mexico. For alternative control, 16 commercial essential oils were tested using three exposure routes to determine their toxic lethal and sublethal effects in the insect developmental cycle. Essential oils in vapor phase bioassay were significantly toxic against S. exigua larvae, with LC₅₀ values ranging from 2.23 to 32.16 mg/ml. Essential oils that killed fewer than 50% by feeding bioassay were chosen to assess sublethal effects in each developmental stage. Exposure to mint, cinnamon, clove, geranium, and citronella oils decreased the average weight of larvae 11 to 43%. Lime, peppermint, and tangerine oils caused an increase of 20 to 37% in the average weight of larvae. Average weight of pupae was not affected. According to the population size, the number of eggs laid with mint or tangerine oil exceeded that expected, although oviposition with other treatments was less than the check, and least oviposition was with clove oil. In most cases about 90% of the eggs hatched, except for clove with 40%, and 76 and 72% hatching with geranium and citronella oils, respectively. Essential oils caused different sublethal to lethal effects promising effectiveness against S. exigua.

Consumption of insects as food usually is related to intake of proteins and other nutrients. Insects also can provide components, especially antioxidants, with nutraceutical potential. Development of food products based on insects should consider these properties. Two types of mezcal were supplemented with two insect pests (Tenebrio molitor L. and Schistocerca piceifrons Walker). By using colorimetric assays, contents of phenolic compounds, free radical-scavenging capacity against the radical generated from 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH), and antioxidant capacity were determined. T. molitor after 30 days of storage, provided 0.995 mg of gallic acid equivalents per gram of dry weight (mg GAE/g DW) in young mezcal, 153.527 mM TE/g DW for scavenging capacity against ABTS using rested mezcal, 20.711 mM TE/g DW for scavenging capacity against DPPH in rested mezcal, and 65.276 mM TE/g DW for antioxidant capacity in young mezcal. S. piceifrons did not contribute as much as T. molitor. This supports use of insects to supplement mezcal and provided evidence of antioxidant potential from insects that remain after storage.

Plants can protect themselves by damaging the digestion of insects. However, some insects can activate responses in their digestive system, more specifically in the insect midgut, to deal with plant defense compounds. This is of ecological relevance as a reflection of adaptive capability of insects. This work focused on digestive proteinases of Pterophylla beltrani Bolivar and Bolivar to evaluate if there were differences in expression profiles depending on sex and sensitivity to cations. Intestinal proteolytic activity in P. beltrani adults was determined by a colorimetric assay. Results were related to sex and 2 years of collection (2018 and 2019). Sensitivity was determined using different cations such as Ca, Mg, Mn, and Zn at 100 mM in the reaction mixture of proteolytic activity. Proteolytic activity was stable between years. Most activity was in males in 2019 (256,325 PAU/g) and to a lesser extent in females in 2018 (207,333.33 PAU/g) and 2019 (205,708.3 PAU/g). Proteolytic activity in the presence of Ca, Mg, and Mn was affected to a lesser percentage of 12% of remnant activity but diminished in the presence of Zn (53.7 to 73.5%). Results showed diversity regarding the presence and sensitivity of digestive proteinases in P. beltrani, which is of ecological importance because it could reflect ability to adapt to defenses of plants associated with diet.

Effect of physical and nutritional conditions such as culture temperature, pH, light, and culture and substrate medium with supplements were assessed for vegetative growth and production of conidia, in addition to virulence against Lepidoptera and Coleoptera pests by strains of Beauveria sp. Dextrose, peptone, and yeast agar with wheat bran or amaranth flour, 23 to 25°C, 7.5-8.5 pH, and obscure light were optimum for radial growth. Light and pH for most production of conidia depended on the fungal strain. Most conidia per gram were produced with 4% amaranth added to oat grain and culture in dextrose, peptone, and yeast broth with 2% wheat bran. Both fungal strains killed 91.1-96.0% of Phyllophaga sp. (Coleoptera: Scarabaeidae) and Spodoptera exigua Hübner and Trichoplusia ni Hübner (Lepidoptera: Noctuidae). Results confirmed the possibility of increased production of B. bassiana conidia by protein supplements and physical growing conditions to maintain pathogenicity.

Indiscriminate use of insecticides to control vectors of malaria, dengue, and yellow fever contaminates the environment and with time, gradually increases insecticide-resistant mosquitoes, making their control increasingly difficult. Use of the parasitic nematode Romanomermis iyengari (Mermithidae) is efficient biological control against mosquitoes, but little is known of the effect of habitat complexity on the success of infection. We determined lethal doses of the nematode on Culex quinquefasciatus (Culicidae) and analyzed the effect of habitat complexity (0, 25, 50, 75, and 100% aquatic debris cover) on successful infection by two lethal loads (10 and 100 parasites per larva). Habitat complexity had no effect on parasitic efficiency of R. iyengari at high concentrations (100 parasites per larva) and significantly decreased parasitic efficiency at low concentrations (10 parasites per larva). Use of combined biological control agents (water bugs (Hemiptera), odonate nymphs (Odonata), and air-breathing fish) of mosquito larvae commonly found in larval habitats should be studied more. Habitat complexity could have a density-dependent effect on parasitic efficiency of R. iyengari on Cx. quinquefasciatus. Complex habitat could affect mobility and ability of a parasite to search for a host. High parasite loads were not affected by habitat complexity and caused high parasite burdens on sampled hosts. Mosquito larvae could reach maturity without being infected by R. iyengari in low parasite loads.

Species of the Papilionidae, Pieridae, and Nymphalidae families of Lepidoptera were inventoried, diversity of habitats of the core area of the ecological reserve “El Tisey-La Estanzuela” (natural protected area) of Nicaragua was analyzed, and butterfly food guilds and efficiency of collection methods were determined. The study was at 11 sites: Bosque Pino Santa Rosa, Bosque Mixto Napoleón, Bosque Ripario, Café Almaciguera, Café Jalacate, Camino, Potrero Zontul, Potrero Cerro Tisey, Potrero Las Brisas, Roble Amarillo Cuchilla, and Roble Amarillo Zontul. Each habitat was systematically sampled using two collection methods (insect net and baited trap) once per week for 4 months (November 2014 to February 2015). An insect net was used with non-linear and linear transects and a trap was baited to attract butterflies for sampling. In total, 2,516 specimens in 18 subfamilies, 59 genera, 93 species, and 22 subspecies were collected. Adelpha paroeca paroeca Bates (Limenitinae), Diaethria pandama Doubleday (Eurytelinae), and Vanessa cardui L. (Nymphalinae) of the Nymphalidae family and Heraclides paeon thrason C. & R. Felder (Papilioninae) of the Papilionidae family were recorded for the first time in Nicaragua. The most abundant species were Hermeuptychia hermes Fabricius, Anartia fatima Fabricius, Heliconius charithonius L., Eurema salome jamapa Reakirt, and Eunica monima Stoll. Low richness and high species equity were recorded at “Bosque Mixto Napoleón” and “Roble Amarillo-Cuchilla”, while other habitats had high richness with low equity. The Potrero Cerro Tisey habitat had the greatest species equity. H. hermes was in 11 environments, and Camino and Potrero Zontul habitats had the greatest similarity of species. Basic information on biological diversity allows efforts to be focused on conserving species.

Sorghum (Sorghum (L.) Moench) is one of the most important cereal crops in the world and produced for food, feed, and forage. However, several species of insect pests affect sorghum production, especially sugarcane aphid, Melanaphis sacchari (Zehntner), the most important recent pest. The objective of this research was to identify composition of functional groups of chemicals during sorghum-aphid interaction. Eight experimental lines and two commercial sorghum hybrids were evaluated at the vegetative and reproductive stages at 70 and 100 days after sowing. The experimental design was a randomized complete block with three replications divided into natural conditions (non-chemical treatment) or with chemical treatment for pest control. The agronomic variables of plant height, leaf area, stalk diameter, internode number, number of aphids per area, and total soluble solids were evaluated. LES267NCT in natural conditions was less infested by aphids and considered a resistant genotype, surpassing commercial hybrid P82G63. Conversely, LESSONU was very infested. Fourier Transform Infrared (FTIR) analysis revealed several functional groups such as OH in hydrogenated aromatic, aliphatic, and phenolic alcoholic compounds, tannins, and methylene groups in aromatic compounds, lipids, and lignin.

The objective of the study was to evaluate the response of non-preference and severity of damage by Melanaphis sacchari (Zehntner) in commercial cultivars of sorghum (Sorghum bicolor (L.) Moench). Effect of antixenosis and enzymatic activity were evaluated in 11 sorghum cultivars with a completely randomized design with 10 replications in a laboratory. In the field, damage severity was evaluated in 10 genotypes with a randomized complete block design with three replications. M. sacchari feeding and reproducing in a laboratory showed less preference for DKS 26, DKS 2805, GW 9320, and GW 1160, which suggested a high level of antixenosis by the genotypes. Genotype DKS 2805 had the most peroxidase activity, suggesting the genotype increased peroxidase activity to resist feeding by M. sacchari. In the field, DKS 2805 and GW 9320 were resistant and moderately resistant to the pest. Resistance of DKS 2805 might be caused by antixenosis and high peroxidase activity, while GW 9320 might be by antixenosis alone. Resistant genotypes DKS 2805 and GW 9320 should be part of an integrated management program against M. sacchari.

Results of a preliminary study on adult scarab beetles (Coleoptera: Scarabaeidae “Pleurosticti”) associated with maize (Zea mays L.) at the municipality of Villa de Zaachila, Oaxaca, Mexico are presented. The objective was to identify species of the white grub complex associated with the crop. Samples were collected each month from March through August 2018. A blacklight trap in the center of the maize plot was used from 1900 to 2300 hours during 3 nights of the new moon period. In total, 1,429 specimens were captured, belonging to 12 species, four genera, four tribes, and three subfamilies of Scarabaeidae. Abundance was greatest in April, coinciding with the start of the rainy season. The genus Anomala Samouelle with five species was most abundant. Anomala flavilla was the most abundant species and together with A. sticticoptera Blanchard, 1850 were reported for the first time in the State of Oaxaca. An annotated checklist with data on distribution, elevation, and associated crops was presented. A key was provided for taxonomic identification of the species studied.

Parasitism by Cirrhencyrtus spp. on Ferrisia virgata Cock and Dysmicoccus brevipes Cockerell associated with rambutan (Nephelium lappaceum L.) crops in Mexico was reported. Parasitoids were randomly sampled in six commercial orchards where synthetic insecticide was not applied. Parasitism by Cirrhencyrtus aeoles (Noyes), Cirrhencyrtus silvia (Noyes), and Cirrhencyrtus pertius (Noyes) was recorded in 15 samples at four localities from 504 samples collected at six localities. This is the first record of these parasitoids in Mexico and new host associations.

Some mites of the family Winterschmidtiidae have symbiotic relationships with eumenine wasps that carry mites in different body cavities. The objective of this work was to study the diversity of mites associated with potter wasps of the genus Zethus. Seventeen individuals belonging to three species of Zethus (Z. aztecus, Z. miscogaster, and Z. montezuma) were recognized from the insect collection of the Universidad Autónoma de Tamaulipas (MIFA-UAT). Of them, six specimens of two species, Z. aztecus, and Z. miscogaster, had phoretic mites adhered to the body, mainly in cavities of the propodeal and metasomal regions. Ninety-two mite specimens were collected, and two species were recognized: Vidia arizonensis and Zethacarus miscogaster, with all being phoretic or resistant nymphs (hypopus). These are the first records of these mites for the States of Coahuila and Tamaulipas, Mexico.

The oil palm, Elaeis guineensis Jacq., is one of the most important oilseed crops in Mexico. Taxonomic identity, damage, and abundance of the defoliator O. cassina fabricii were studied in oil palm plantations at Tabasco, Mexico. Sampling was at nine localities at 3-month intervals from September 2019 to November 2020. On each date, 30 palm trees were randomly sampled per plantation. On each palm tree, the leaf surfaces of four fronds in the lower-middle part of the plant canopy were examined. Occurrence was relatively scarce (0-0.12 larva per frond), and damage was incipient. At all localities, O. cassina fabricii was phytophagous, which broadens its geographical distribution in the oil palm crop in the Neotropical region of the world. Variation in altitude from 7-57 m above sea level of oil palm plantations was not statistically correlated with the total number of larvae of O. cassina fabricii per locality. Probable factors that might be involved in the low occurrence and damage by the species in the oil palm agroecosystem of the study area were discussed.

Se determinó el comportamiento poblacional del pulgón amarillo del sorgo (PAS) Melanaphis sacchari (Zehntner) y enemigos naturales, en tres localidades del estado de Guanajuato, México. Mediante muestreos con red entomológica y trampas con agua jabonosa, en parcelas semi-comerciales de sorgo con diferentes genotipos, en condiciones de riego y de temporal, sin aplicación de insecticidas. En sorgo con riego, el PAS ocurrió a partir de la etapa de diferenciación floral a las 749 UC acumuladas a partir de la nacencia, mientras que, en temporal la presencia ocurrió a partir de la quinta hoja verdadera, cerca de las 500 UC acumuladas. Se observaron 12 especies de entomófagos: Hippodamia convergens Guérin-Méneville, la catarina asiática Harmonia axyridis Pallas, y la catarina café Scymnus loewii Mulsant, la avispa Asaphe sp. (Pteromalidae), hiperparasitoide de Aphidius colemani (Dalmen); Diplazon probablemente scutellaris (Cresson) (Ichneumonidae), parasitoide de moscas sírfide Allograpta obliqua (Say), y A. exótica (Wiedemann), primer registro en el Bajío, México; y a Dinocampus (=Perilitus) coccinellae (Braconidae), parasitoide de la catarina anaranjada.

Se realizaron recolectas semanales en un cultivo de maíz (Zea mays L.) con red de barrido, platos amarillos, y trampa Malaise en Colima, México. Registrando e ilustrando 12 especies de coccinélidos, de las cuales Selvadius maderi (Nunenmacher) y Scymnus (Pullus) pictilis Gordon se reportan por primera vez para México; Diomus roseicollis (Mulsant), Epilachna difficilis Mulsant, Scymnobius spp., Scymnus (Pullus) louisianae Chapin, y Scymnus (Pullus) tenebrosus Mulsant se registran por primera ocasión en cultivo de maíz. Usando el estimador no paramétrico ACE se espera una riqueza de 32.7 especies, por lo cual en el presente estudio solo se registró el 36% de la riqueza probable, lo que evidencia el potencial por conocer el estado de la familia Coccinellidae en el área de estudio.

Conocer la taxonomía de himenópteros parasitoides es esencial para el entendimiento de su biodiversidad, conservación, y reproducción. Se corroboró la identidad morfológica de tres especies del género Chelonus reportadas como parasitoides de gusano cogollero asociados a maíz en Durango, México (Chelonus cautus, C. sonorensis, y C. insularis), a la par se analizaron ocho morfotipos con caracteres morfológicos similares a estas especies, pero con patrones de coloración distintos en el metasoma, caracter no distintivo o único para su identificación. Se utilizaron claves taxonómicas, pruebas de PCR, así como búsquedas bibliográficas que indicaron que C. insularis y C. sonorensis, así como las ocho morfoespecies, morfológica, y genéticamente pertenecen a la misma especie [C. insularis]. Chelonus cautus fue distinto a C. insularis y C. sonorensis, además pertenece a otro género diferente al nominal (Microchelonus cautus). Estos resultados permitieron conocer acerca del origen de estos parasitoides (diagnosis inicial) y reconocer que tienen nombres inexactamente establecidos, lo que permitirá su futura redescripción.

El “frailecillo” Macrodactylus nigripes Bates es considerado una de las plagas que afecta a varios cultivos en México, entre ellos el durazno (Prunus persica (L.) Batsch). El objetivo de este trabajo fue extraer e identificar los compuestos volátiles de P. persica con Headspace estático (HE) y Headspace dinámico (HD). De los compuestos identificados se evaluó a través de bioensayos con electroantenografía (EAG) y con olfatómetro la actividad biológica que éstos tienen en la comunicación química de M. nigripes. Se extrajeron e identificaron compuestos de P. persica con Headspace dinámico (HD) y Headspace estático (HE), a través de cromatografía de gases acoplada a espectrometría de masas (CG-EM). Se llevaron a cabo pruebas de electroantenografía (EAG) y olfatómetro con R-(+)-limoneno y (Z)-3-hexenil acetato, que provocan actividad biológica en melolóntidos. En pruebas con EAG se obtuvieron respuestas antenales significativas a R-(+)-limoneno y (Z)-3hexenil acetato en ambos sexos. En el olfatómetro se observó que R-(+)-limoneno no produjo una respuesta significativa, mientras que (Z)-3-hexenil acetato generó respuestas significativas a las concentraciones 200 y 250 µl/ml.

Se describe una nueva especie de mosca blanca de pupa pálida, Aleuropleurocelus palidonigrans Carapia-Ruiz y Sánchez-Flores sp. nov., encontrada en Acapulco, Guerrero, México en el envés de hojas de Guazuma ulmifolia Lam. Se proporcionan microfotografías de estructuras morfológicas de puparios y se discute la separación con otras especies cercanas de Aleuropleurocelus.

The pale owl butterfly, Caligo telamonius (C. Felder & R. Felder, 1867), was recorded for the first time in the State of Hidalgo, Central Mexico. This extends the known distribution of the species 115 km north of the northernmost specimen collected in eastern Mexico. Ecological data and environmental characteristics of the habitat where the species were collected were described.