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Polistes paper wasps in the Fuscopolistes subgenus (Hymenoptera: Vespidae) can be serious pests when they swarm at tall man-made structures. Chemical attractants may be useful to trap such paper wasps when they achieve pest status. Polistes venom has been shown to elicit a variety of behavioral responses in congeneric wasps, making it a source for potential chemical attractants. The compound N-(3-methylbutyl)acetamide is a principal volatile component in the venom of many female vespid wasps, including numerous Polistes species. We report the presence of N-(3-methylbutyl)acetamide in autumn gynes of Polistes metricus Say, Polistes bellicosus Cresson, and Polistes dorsalis (F.), as well as workers of Polistes aurifer (Saussure), P. bellicosus, P. metricus, and P. dorsalis. In field tests conducted in Florida, Georgia, South Carolina, and Washington, N-(3-methylbutyl)acetamide attracted male and female P. aurifer and P. metricus, as well as male P. dorsalis and P. bellicosus. Thus, N-(3-methylbutyl)acetamide may be a useful lure for trapping these paper wasps in pest situations.

We investigated associative learning of food odors by the European paper wasp Polistes dominula Christ (Hymenoptera: Vespidae) because of consistent low rates of attraction to food materials in laboratory assays. We hypothesized that wasps in nature exhibit nonspecific food-finding behavior until locating a suitable food, and then respond more strongly and specifically to odors associated with that food reward. Female P. dominula workers exhibited higher rates of attraction in a flight tunnel to piped odors of fermented fruit purees following previous experience with that puree, compared to wasps with no prior experience with the fermented fruits. Attraction behavior included upwind-oriented flight and casting within the odor plume, indicative of chemoanemotaxis. Synthetic chemicals representative of volatiles P. dominula may encounter in nature while foraging was also tested. Similar increases in attraction responses occurred following feeding experience with a sugar solution that included either 3-methyl-1-butanol or pear ester, but not eugenol. These experimental results support the hypothesis of associative learning of food odors in P. dominula. We discuss the ecological relevance of our results and suggest an alternative approach to trap paper wasps in pest situations utilizing learned chemical attractants.

A combination of arena,Y-tube olfactometer, and flight tunnel assays were used to determine responses of male and reproductive female Polistes exclamans Vierick (Hymenoptera: Vespidae) to odors and extracts of conspecific males and females, as potential pheromone-mediated sexual behaviors. Males rubbed the sternites of the gaster on filter paper in response to extracts of the female mesosoma and gaster, indicating possible scent-marking. In a Y-tube olfactometer, females oriented to extracts of the male head, gaster, legs, seventh sternite, and mandibular glands. In the olfactometer, males oriented to extracts of the female whole body, but were repelled by extracts of the female head. Both females and males oriented to solvent washes of glass jars that held wasps of the opposite sex, as well as volatile collections from the opposite sex. In a flight tunnel, males and females both exhibited chemoanemotaxis that consisted of upwind flight and close range casting in response to odor piped into the tunnel from live wasps of the opposite sex. Males mounted a female wasp model treated with an extract of the female mesosoma. Together, these experiments suggest pheromones stimulate male scent-marking, attraction of females to males and males to females, and mounting, in P. exclamans. Results indicate the mesosoma as a source of female pheromones, and the legs, gastral sternal glands, and mandibular glands, as male pheromone sources.

Extensive rearing of monarch larvae (Danaus plexippus L.) through the citizen science Monarch Larva Monitoring Project (MLMP) revealed that monarchs' primary parasitoids are flies in the family Tachinidae and that these parasitoids result in appreciable larval mortality. We document the tachinid community that attacks monarchs in the United States, evaluate their relative frequency, and examine variation in their specificity, oviposition strategy, and use of host stages. Based on results of rearing >20,000 monarchs by MLMP volunteers, overall parasitism by tachinids across life stages was 9.8% (17% for monarchs collected as fifth instars). We identified the flies that emerged from 466 monarch hosts, and found seven Tachinidae species. In decreasing order of frequency, these included Lespesia archippivora (Riley), Hyphantrophaga virilis (Aldrich & Webber), Compsilura concinnata (Meigen), Leschenaultia n. sp., Madremyia saundersii (Williston), Lespesia sp., and Nilea erecta (Coquillett). Lespesia sp., Leschenaultia n. sp., and N. erecta had not been previously reported as monarch parasitoids, and Leschenaultia n. sp. is apparently undescribed. We include new state records (Texas and Iowa) for C. concinnata. Lespesia archippivora and C. concinnata were overrepresented as parasitoids of later instars and were absent from monarchs collected as eggs, but H. virilis and Leschenaultia sp., which lay their eggs on foliage, were reared from caterpillars collected as eggs. To our knowledge, we include the first report of multiparasitism of monarchs, in which more than one parasitoid species emerged from a host. The biology of the tachinid parasitoids we identified and their relationship with monarchs is examined.

The 2018 student debates of the Entomological Society of America were held at the Joint Annual Meeting for the Entomological Societies of America, Canada, and British Columbia in Vancouver, BC. Three unbiased introductory speakers and six debate teams discussed and debated topics under the theme ‘Entomology in the 21st Century: Tackling Insect Invasions, Promoting Advancements in Technology, and Using Effective Science Communication’. This year’s debate topics included: 1) What is the most harmful invasive insect species in the world? 2) How can scientists diffuse the stigma or scare factor surrounding issues that become controversial such as genetically modified organisms, agricultural biotechnological developments, or pesticide chemicals? 3) What new/emerging technologies have the potential to revolutionize entomology (other than Clustered Regularly Interspaced Short Palindromic Repeats)? Introductory speakers and debate teams spent approximately 9 mo preparing their statements and arguments and had the opportunity to share this at the Joint Annual Meeting with an engaged audience.

(Z) -11-Hexadecenal (Z11-16ALD) is a component of the sex pheromone, or a sex attractant, of a number of moth species. Traps baited with this compound in early spring in eastern Washington State captured numbers of males of Egira rubrica (Harvey), Stretchia plusiaeformis (H. Edwards), and Annaphila danisticta (Grote) (all Lepidoptera: Noctuidae), indicating its function as a sex attractant for these species. This new knowledge may be important to pest managers that monitor moths with Z11-16ALD because such non-target responders to a lure can increase monitoring costs and be counted as “false positives” for pest species.