The confused flour beetle, Tribolium confusum Jaquelin Du Val, 1868, is a common pest insect known for attacking and infesting stored flour and grain. Biodegradable and ecologically natural products such as essential oils are emerging candidates for replacement of usually applied chemical pesticides. This work reported the chemical composition and effects caused by young and mature leaves essential oils (EOs) from Eucalyptus globulus Labill. against T. confusum. For both oils, no significant differences between yields were observed, being 1,8-cineole the main common constituent. Mature leaves extracts were rich in oxygenated mono-and sesquiterpenes, whereas young leaves showed greater content of nonoxygenated compounds. Bioassay was performed using EOs and 1,8-cineole solutions at different concentrations and time intervals. Adult mortality increased according to concentration and exposure time; young leaves extracts exhibited the greater effectiveness, highest mortalities (31.67%) at the minor time (2 h). At the lowest concentrations, 1,8-cineole solutions and mature leaves EOs did not achieve 100% mortality even when the bioassay was concluded (12 h), while at major doses no insects were alive. These results suggested that young and mature EOs from E. globulus constitute an alternative natural product to the control of T. confusum, since young leaves extracts, rich in monoterpene and sesquiterpene hydrocarbons, may be potential eligible candidates considering their noticeable insecticidal effects at low applied concentrations and short times of exposure.

Diabrotica speciosa speciosa (Germar) es uno de los crisomélidos más ampliamente distribuídos en cultivos de la Argentina. Se estudió la morfología de los estados preimaginales, tabla de vida y el comportamiento reproductivo. El desarrollo se llevó a cabo bajo condiciones controladas de laboratorio. Bajo estas condiciones se establecieron los siguientes parámetros poblacionales: tiempo de desarrollo, tasa reproductiva, tasa de crecimiento intrínseco y se confeccionó una tabla de vida horizontal.

RESUMENCholoepus hoffmanni Peters, 1858 ha sido poco estudiada en Honduras, el país más septentrional de su distribución. Presentamos algunas observaciones sobre su distribución, dieta, comportamiento y amenazas en el país. Los registros confirmados para la especie en Honduras incluyen 11 documentados con anterioridad y seis nuevos, presentados aquí. De los 17, solamente seis corresponden a observaciones directas, uno de los cuales extiende la distribución global conocida hacia el norte de Honduras (Los Naranjos, departamento de Colón). Los ejemplares silvestres se alimentaron, principalmente, de Cecropia Loefl., pero también de Inga vera Willd. La pérdida acelerada del hábitat y el comercio ilegal pueden convertirse en amenazas para la especie en Honduras.

No abstract

Megachile is the largest genus of the family Megachilidae, being widely distributed throughout temperate and tropical areas of the world. The validity of M. (Chrysosarus) and M. (Dactylomegachile) was investigated based on a cladistic analysis of 63 characters of adult morphology of 14 taxa. The single most parsimonious tree (181 steps, CI=0.60; RI=0.63) resulting from an implied weighting analysis recovered M. (Chrysosarus) and M. (Dactylomegachile) as monophyletic groups. Both subgenera are redescribed and the value of the most frequently used characters in the taxonomy of Megachile is discussed.

Abstract:The type specimens (all current categories) of Chrysomelidae s.l. deposited in this Museum are listed; 125 names are recorded, 85 of them (68 percent) are represented here by name-bearing types ('primary' types), five of them dubious. The family is taken in its broadest sense, including the Bruchinae, Hispinae (along with the former Cassidinae), and other groups sometimes considered as separate families. The specific and subspecific names were alphabetically filed, followed by the generic ones as they were spelled in the original publication, or the generic and specific names in the case of subspecies and varieties. Later combinations and/or current binomina are mentioned insofar as these are known to the authors. Two lists are added: 1. of specimens labelled as types of unavailable names, chiefly those not found in the literature, and supposedly not published, and 2. of specimens labelled as types, but not originally included as such, and published or not after the original description.Key words: Chrysomelidae, Coleoptera, type specimens, Argentina.Resumen: Catálogo de los tipos de Chrysomelidae sensu lato (Insecta, Coleoptera, Polyphaga) depositados en el Museo Argentino de Ciencias Naturales, Buenos Aires. Se catalogan los ejemplares típicos, de todas las categorías aceptadas, de Chrysomelidae s.l. conservados en este museo; se registran 125 nombres, 85 de ellos (68 por ciento) representados aquí por tipos portadores de nombres (tipos 'primarios'), cinco de ellos dudosos. La familia se toma en su concepto más amplio, incluyendo a las Bruchinae, las Hispinae (con las anteriores Cassidinae) y otros grupos a veces considerados como familias separadas. Los nombres específicos y subespecíficos fueron ordenados alfabéticamente; a estos siguen los de los géneros, así como se publicaron originalmente, o de los géneros y especies en el caso de las subespecies y variedades. Se mencionan las combinaciones ulteriores y/o los binomios en uso, hasta donde son conocidos por los autores. Se agregan dos listas: 1. de los ejemplares rotulados como tipos, de nombres no disponibles, principalmente aquellos no hallados en la bibliografía, y supuestamente no publicados, y 2. de los ejemplares rotulados como tipos, pero no incluidos originalmente como tales, publicados o no después de la descripción original.

The genus Diabrotica has over 400 described species, the majority of them neotropical. However, only three species of neotropical Diabrotica are considered agricultural pests: D. speciosa, D. balteata, and D. viridula. D. speciosa and D. balteata are polyphagous both as adults and during the larval stage. D. viridula are stenophagous during the larval stage, feeding essentially on maize roots, and polyphagous as adults. The larvae of the three species are pests on maize, but D. speciosa larvae also feed on potatoes and peanuts, while D. balteata larvae feed on beans and peanuts. None of these species express a winter/dry season egg diapause, displaying instead several continuous, latitude-mediated generations per year. This hinders the use of crop rotation as a management tool, although early planting can help in the temperate regions of the distribution of D. speciosa. The parasitoids of adults, Celatoria bosqi and Centistes gasseni, do not exert much control on Diabrotica populations, or show potential for inundative biocontrol plans. Management options are limited to insecticide applications and Bt genetically modified (GM) maize. Other techniques that show promise are products using Beauveria bassiana and Heterorhabditis bacteriophora, semiochemical attractants for monitoring purposes or as toxic baits, and plant resistance.

Flea beetles of alligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae), were collected in Argentina, Uruguay, Paraguay, and Brazil. Species in the genera Disonycha Chevrolat, Agasicles Jacoby, and Systena Chevrolat were frequently found on this weed. Systena nitentula Bechyné 1954 was the most abundant within Systena. This species is reported for the Þrst time from Argentina at north of 308 S. The male is described and holotype female is redescribed adding new diagnostic characters: mouthparts, hind wings, metendosternite, and male and female genitalia. S. nitentula is recognized by the combined characters of piceous elytra with J-shaped vittae, a small spermatheca pump, and internal median lobe sac with Þve sclerotized plates. Differences in color patterns between S. nitentula, S. tenuis Bechyné , and S. s-littera L. also are considered. S. nintentula presents three instars that can be separated through head width. New biological data based on laboratory rearing and Þeld observations shows that S. nintentula could be a monophagous species strongly associated to the alligator weed growing in terrestrial conditions. This information promotes S. nintentula as a potential biocontrol agent of this invasive weed.