Wasps

Some Ichneumonidae wasps, including the genus Acrotaphus Townes, 1960 (Ephialtini: Pimplinae), induce behavioral modification in their spider hosts. Acrotaphus is a New World parasitoid wasp genus with 26 described species. This genus belongs to the Polysphincta genus group, which are ectoparasitoids of spiders of the Araneidae. In this study, we describe a new species (Acrotaphus wagnerianae sp. n.) found in the Brazilian Amazon. In addition, we discuss for the first time the behavioral modification of spiders of the Wagneriana genus (Araneidae) by wasps of the Polysphincta genus group.

The fire-hardened nests of mud-dauber wasps, although underreported, are occasionally recovered from prehistoric settlements across much of eastern North America. Because mud dauber wasp species tend to build in sheltered environments, burned nests are periodically used as indirect evidence for prehistoric construction. Other research applications are generally not pursued, such as paleoenvironmental modeling and species I.D. of the arthropod material very rarely preserved in the nests. Past efforts in this regard have produced mixed results, and often lead to the fruitless destruction of archaeological nests. The work described here has two purposes, first, we attempt to identify a technique that would allow archaeologists to assess the integrity and contents of prehistoric nests. Second, we inventory the species, contexts, and chronology of a nest assemblage collected over a 50-year period from sites in the Yazoo Basin of Mississippi. For the first goal, two methods of radiographic imaging were used with limited success. The nest inventory suggests that most date to the Mississippian/Protohistoric periods (ca. 1000-1700 A.D.), a time when relatively substantial architecture was widespread among pre-European societies in this region.

—Sex attraction studies were carried out to investigate the mate-finding behaviour of invasive Vespula vulgaris (Linnaeus) (Hymenoptera: Vespidae) wasps. Delta traps were baited with live, caged males, and gynes (virgin queens) of V. vulgaris to determine whether either sex produced a long-range sex attractant. Traps baited with gynes caught 71 males, while the controls and live-male wasp baited traps did not catch gynes. Wind tunnel trials were performed to verify if the signal produced by the gynes was chemical in nature. First, V. vulgaris males were flown to live caged gynes, where more than half of the males tested flew upwind in a zigzagging pattern and made contact with caged gynes. Males were also flown to hexane rinses of gynes and flew upwind in a zigzagging pattern towards the gyne extract, although none made contact with the cotton roll stimulus. The results presented here demonstrate conclusively that V. vulgaris gynes produce a sex pheromone. Résumé—Des e ´tudes d'attraction sexuelle ont e ´té réalisées afin d'e ´tudier le comportement de recherche de partenaire chez la guêpe envahissante Vespula vulgaris (Linnaeus) (Hymenoptera: Vespidae). Nous avons appâtés des pièges Delta avec des mâles et des gynes (reines vierges) de V. vulgaris vivants et encagés pour déterminer si l'un ou l'autre des sexes produit une substance d'attraction sexuelle a ` longue portée. Les pièges appâtés de gynes ont capturé 71 mâles, alors que les pièges témoins et les pièges contenant des guêpes mâles vivantes n'ont attrapé aucune gyne. Des essais en soufflerie aérodynamique ont permis de vérifier si le signal produit par les gynes est de nature chimique. D'abord, nous avons introduit des mâles de V. vulgaris en vol en direction de gynes vivantes encagées: plus de la moitié des mâles se sont dirigés dans le vent en zigzagant et ont fait contact avec les gynes encagées. Nous avons aussi introduit des mâles en vol en direction de rinçages de gynes a ` l'hexane: les mâles ont volé en zigzagant dans le vent vers l'extrait de gynes, bien qu'aucun n'ait fait contact avec le rouleau de coton servant de stimulus. Nos résultats démontrent de manière décisive que les gynes de V. vulgaris produisent une hormone sexuelle.

Explotación de himenópteros melíferos entre etnias del Gran Chaco: Una mirada etnobiológica
Nicolás M. Kamienkowski, y Pastor Arenas
RESUMEN
Se presenta un panorama general de los conocimientos indígenas y criollos del Gran Chaco acerca de la biodiversidad de los himenópteros melíferos, la actividad de recolección de miel asociada a la cultura material, el uso de los productos obtenidos y ciertos aspectos socioeconómicos y culturales relacionados. La información proviene de trabajos de campo hechos desde la década de 1970 y de una amplia revisión bibliográfica. Se destaca el profuso conocimiento acerca de dichos insectos por los indígenas y criollos, en contraste con la escasez en su documentación. Se resaltan los diversos usos de los productos del meleo. Por último se manifiesta el lugar de importancia que dicha actividad de explotación ocupa dentro de los grupos indígenas y criollos del Gran Chaco, dando cuenta de las relaciones económicas, sociales, el comportamiento cultural específico y los nexos con el mundo sobrenatural vinculados con la actividad.