Bioreplicated visual features of nanofabricated buprestid beetle decoys evoke stereotypical male mating flights.

Recent advances in nanoscale bioreplication processes present the potential for novel basic and applied research into organismal behavioral processes. Insect behavior potentially could be affected by physical features existing at the nanoscale level. We used nano-bioreplicated visual decoys of female emerald ash borer beetles (Agrilus planipennis) to evoke stereotypical mate-finding behavior, whereby males fly to and alight on the decoys as they would on real females. Using an industrially scalable nanomolding process, we replicated and evaluated the importance of two features of the outer cuticular surface of the beetle's wings: structural interference coloration of the elytra by multilayering of the epicuticle and fine-scale surface features consisting of spicules and spines that scatter light into intense strands. Two types of decoys that lacked one or both of these elements were fabricated, one type nano-bioreplicated and the other 3D-printed with no bioreplicated surface nanostructural elements. Both types were colored with green paint. The light-scattering properties of the nano-bioreplicated surfaces were verified by shining a white laser on the decoys in a dark room and projecting the scattering pattern onto a white surface. Regardless of the coloration mechanism, the nano-bioreplicated decoys evoked the complete attraction and landing sequence of Agrilus males. In contrast, males made brief flying approaches toward the decoys without nanostructured features, but diverted away before alighting on them. The nano-bioreplicated decoys were also electroconductive, a feature used on traps such that beetles alighting onto them were stunned, killed, and collected.

Field screening of known pheromone components of longhorned beetles in the subfamily Cerambycinae (Coleoptera: Cerambycidae) in Hungary.

Five compounds known to be pheromone components of longhorned beetles (Coleoptera: Cerambycidae) in the subfamily Cerambycinae were field-tested as attractants and possible pheromones for the cerambycid fauna of Hungary. Nine cerambycid species were caught in baited traps. Large numbers of both sexes of the cerambycine species Molorchus umbellatarum Schreb. were caught in traps baited with (2R*,3S*)-octanediol, while the diastereomeric (2R*,3R*)-octanediol was to some extent attractive as well. This is the first report on an aggregation attractant and a likely pheromone for a species in the cerambycine tribe Molorchini. The results of our study support the hypothesis that the diol/hydroxyketone pheromone motif is characteristic of and highly conserved within the subfamily Cerambycinae. Intraspecific chemical communication is summarized for the subfamily Cerambycinae, and possible links between taxonomy, insect behaviour, and pheromone structures are described.