Flight behavior of four species of Holotrichia chafer (Coleoptera: Scarabaeidae) with different habitat use

Insect flight behavior varies among species and selective pressures underlying the diversification of flight performance remain to be fully elucidated. Comparisons of flight behavior among congeners with differing ecologies can contribute to gaining a better understanding of the mechanisms underlying the diversification of insect flight behavior. In this study, we compared the laboratory arena flight performance of four species of nocturnal Holotrichia black chafers (Coleoptera: Scarabaeidae) based on three-dimensional reconstructions of flight trajectories. Principal component analysis was applied to six kinematic parameters to summarize the flight performance of each species. We found that the flight of H. parallela, which feeds on the leaves of hardwood species, was faster and higher than that of the other three species (H. kiotonensis, H. picea, and H. convexopyga), which typically feed on herbaceous plants. However, maneuverability (rotational component) did not differ significantly among the four species. We further compared the flight velocities of H. parallela and H. kiotonensis using a tethered flight mill system. Similar to the free-flight observations, the velocity of H. parallela flights was significantly greater than that of H. kiotonensis. The interspecific difference in velocities may be associated with differences in spatial distribution of their host plants.

Automated summary

This study compared the flight performance of four species of nocturnal Holotrichia black chafers, finding that the species feeding on hardwood leaves had faster and higher flights compared to those feeding on herbaceous plants. However, maneuverability did not differ significantly among the species. Flight velocities were further compared between two species, showing a significant difference possibly related to differences in the spatial distribution of their host plants.