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The longhorn beetle Graphisurus fasciatus (Degeer) ranges from southeastern Canada to Florida and west to Texas, and has frequently been caught during field trials testing attraction of other cerambycid species to their synthesized pheromones. Collections of headspace volatiles from live beetles revealed that males but not females produce a polyketide compound identified as (4R,6S,7E,9E)-4,6,8-trimethylundeca-7,9-dien-3-one ([4R,6S,7E,9E]-graphisurone). Field trials verified that beetles of both sexes were attracted to the synthesized compound, indicating that it is an aggregation-sex pheromone. This structure represents a new structural motif among cerambycid pheromones, and a new natural product. While this study was in progress, the same compound was isolated from males of the South American cerambycid Eutrypanus dorsalis (Germar), in the same subfamily (Lamiinae) and tribe (Acanthocinini) as G. fasciatus. Field trials in Brazil confirmed that (4R,6S,7E,9E)-graphisurone is also an aggregation-sex pheromone for E. dorsalis, and a possible pheromone for two additional sympatric lamiine species, Hylettus seniculus (Germar) (Acanthocinini) and Oreodera quinquetuberculata (Drapiez) (tribe Acrocinini). These results indicate that graphisurone may be shared among a number of related species, as has been found with many components of cerambycid pheromones., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

As part of a long-term project on unraveling the use of pheromones in the large beetle family Cerambycidae, field trials were conducted with generic blends of known cerambycid pheromones at a desert site in southern California. In the first year of testing (2022), the species Eustromula valida (LeConte) (subfamily Cerambycinae, tribe Elaphidiini) and Aethecerinus latecinctus (Horn) (Cerambycinae, Trachyderini) were weakly attracted to one of the lure blends. In follow-up trials in 2023, only E. valida were caught, and collection of volatiles from both sexes of E. valida determined that males sex-specifically produced 3-methylthiopropan-1-ol (methionol), a compound that was not in the tested lure blends. Beetles of both sexes were strongly and specifically attracted to this compound in field bioassays, verifying that it is an aggregation-sex pheromone. No sympatric species were attracted to methionol while it was deployed in the field. Several recent studies have identified methionol as a pheromone component for other cerambycid species in both North and South America, suggesting it may represent another common pheromone component within the Cerambycidae., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Firefly flashes are well-known visual signals used by these insects to find, identify, and choose mates. However, many firefly species have lost the ability to produce light as adults. These "unlighted" species generally lack developed adult light organs, are diurnal rather than nocturnal, and are believed to use volatile pheromones acting over a distance to locate mates. While cuticular hydrocarbons, which may function in mate recognition at close range, have been examined for a handful of the over 2000 extant firefly species, no volatile pheromone has ever been identified. In this study, using coupled gas chromatography - electroantennographic detection, we detected a single female-emitted compound that elicited antennal responses from wild-caught male winter fireflies, Photinus corruscus. The compound was identified as (1S)-exo-3-hydroxycamphor (hydroxycamphor). In field trials at two sites across the species' eastern North American range, large numbers of male P. corruscus were attracted to synthesized hydroxycamphor, verifying its function as a volatile sex attractant pheromone. Males spent more time in contact with lures treated with synthesized hydroxycamphor than those treated with solvent only in laboratory two-choice assays. Further, using single sensillum recordings, we characterized a pheromone-sensitive odorant receptor neuron in a specific olfactory sensillum on male P. corruscus antennae and demonstrated its sensitivity to hydroxycamphor. Thus, this study has identified the first volatile pheromone and its corresponding sensory neuron for any firefly species, and provides a tool for monitoring P. corruscus populations for conservation and further inquiry into the chemical and cellular bases for sexual communication among fireflies., (© 2023. The Author(s).)