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The biological behaviour and morphometric data from two allopatric isolates of Echinostoma paraensei (Rio Bonito - RB and Sumidouro - SU) collected from naturally infected Nectomys squamipes from two secluded Atlantic Forest fragments were studied. Mice that had been experimentally infected with ten encysted metacercariae of each isolate were monitored weekly in two trials to analyse worm burden and the kinetics of worm distribution along the intestine. The total number of uterine eggs, wet weights and measurements of the worms and body, acetabulum, testes and ovaries were also analysed. The RB isolate showed a higher worm burden, 7.7+/-0.8, and a longer life span, 16 weeks, compared to a worm burden of 5.8+/-1.1 and life span of 9 weeks for the SU isolate. Worms of the RB isolate were clustered in the duodenum and in the bile duct while the SU isolate worms were dispersed along the small intestine of infected mice. Both isolates developed similarly as regards morphometric data and wet weight, although the total number of uterine eggs was greater in RB. The degree of intraspecific variation observed in the worm distribution along the intestine, worm burden and life span raises questions regarding the use of these criteria for species differentiation. These findings suggest that variation in biological parameters found between the E. paraensei isolates could result from geographical isolation and, in particular, the environmental conditions of transmission. Further studies on E. paraensei polulations from different forest fragments will contribute towards an understanding of the speciation of this parasite.

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El objetivo del estudio fue determinar la efectividad de captura de bracónidos (Hymenoptera: Braconidae) con platos-trampa de color (amarillo, azul, crema y verde), a dos alturas (0 y 90 cm) durante cuatro semanas en el Área Natural Protegida “Cerro Punhuato” (Morelia, Michoacán, México). La reflectancia de cada color se midió con un espectrofotómetro analítico de campo. Se capturaron 104 especímenes pertenecientes a 14 subfamilias y 28 géneros. Los platos-trampa de color amarillo y verde capturaron la mayor cantidad de especímenes y la mayor diversidad de géneros. La similitud estimada con el índice de Bray-Curtis entre ambos colores fue de 56,5 %. Los platos-trampa amarillos instalados a nivel del suelo superaron significativamente la captura de los platos verdes en una semana. El nivel de reflectancia que tienen los platos-trampa verdes y amarillos es muy similar en los intervalos de 360 a 530 nm, lo que posiblemente indique que éste sea el intervalo de longitud de onda en que los bracónidos son atraídos por estos colores.

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BACKGROUND The multiple nucleopolyhedrovirus of Spodoptera frugiperda (SfMNPV) plays an important role in regulating its natural host and has high potential for use as a bioinsecticide. However, information about how agricultural practices such as fertilization and plant biotic interactions affect the biocontrol efficacy of SfMNPV is limited. In this study, we examined how multitrophic maize–mycorrhiza–insect herbivore interactions affect the biocontrol efficacy of SfMNPV against S. frugiperda under full and reduced mineral nitrogen fertilization. Two fully factorial greenhouse pot experiments with three factors were performed: (i) arbuscular mycorrhizal fungi (AMF) (with and without AMF), (ii) nitrogen fertilization (50% and 100% N), and (iii) insect (with and without of S. frugiperda). The biocontrol efficacy of SfMNPV against S. frugiperda was examined using detached leaves under controlled environmental conditions. RESULTS Associating maize with AMF resulted in multitrophic cascade effects. Plants with AMF showed suppression of plant growth and increased leaf N and P content, which coincided with increased foliar herbivory and larval biomass that finally reduced the susceptibility of S. frugiperda to SfMNPV. Reduced levels of N fertilization mitigated these observed cascade effects on the biocontrol efficacy of SfMNPV with maize mycorrhizas. CONCLUSION Our results show that AMF can modulate S. frugiperda–SfMNPV interactions via plant‐mediated phenotypic responses to the mycorrhizal association and are most likely linked with increased leaf food quality for S. frugiperda. These results call for further studies to address the mode of interaction and possible implications for pest management in maize agroecosystems. © 2021 Society of Chemical Industry.

Los agathidinos forman un grupo de avispas parasitoides que atacan larvas de lepidópteros. Algunas especies se han utilizado con éxito en programas de control biológico de plagas agrícolas. El objetivo de este trabajo fue actualizar la lista de especies de Agathidinae de México e informar sobre nuevos registros para el país y algunas entidades. Se realizaron cuatro estancias en California, Estados Unidos, para revisar el material mexicano. Además, se consideró el material depositado en la Universidad Autónoma de Tamaulipas (UAT) y en la Universidad Michoacana de San Nicolás de Hidalgo (UMSNH). También se hizo una revisión de literatura que incluyera al menos una especie en el país. Dos especies, Agathis gibbosa (Say) y Pneumagathis spiracularis (Muesebeck), son nuevos registros para México. A nivel mundial, se conocen 51 géneros y 1 177 especies de agathidinos, y para México se registran 24 géneros y 127 especies (hasta diciembre de 2015). Aún no se ha identificado todo el material en varias colecciones del país, por lo que se estima la existencia de más géneros y especies.

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