Navigating Urban Environments Reshapes Dispersal Traits of the Invasive Spotted Lanternfly

Abstract

Urbanization and biological invasions are two dominant drivers of global change, yet their joint effects on dispersal-related trait evolution remain poorly understood. Cities often facilitate the establishment and spread of nonnative species through anthropogenic transport, ecological disturbance, and favorable microclimates, but they may also impose novel selective pressures that reshape traits linked to movement and colonization. Here, we examine these interactions in the spotted lanternfly, Lycorma delicatula, an invasive planthopper that has rapidly expanded across the northeastern United States since 2014. We quantified forewing size and shape in adults collected from urban and rural habitats in the native range (Shanghai, China), and from individuals in the invasive northeastern United States from Pennsylvania to Connecticut, with more intensive sampling in New York City, enabling us to evaluate the combined effects of urbanization and invasion on wing morphology. We measured wing area and length from photographs and quantified wing shape using geometric morphometrics, and compared size, shape, and morphological disparity among groups. Our analyses revealed contrasting responses of wing size and wing shape to urbanization and invasion. Forewing area and length increased consistently with urbanization and building height in both ranges, indicating that larger wings are associated with more urbanized habitats and suggesting that wing size may be important for navigating fragmented, vertically complex city environments. In contrast, wing shape did not vary significantly with urbanization itself, but it diverged between ranges: invasive U.S. individuals had longer, narrower forewings than native Chinese individuals. Wing shape variance was also significantly greater in the invasive range. Together, these results indicate that different components of dispersal morphology respond to different eco-evolutionary pressures, with wing size tracking contemporary urban conditions and wing shape reflecting invasion history and expansion through heterogeneous environments. Our findings suggest that urban environments may do more than facilitate invasion through opportunity alone; they may also contribute to the reshaping of dispersal traits as invasions unfold. By linking urban environmental structure with morphological divergence and increased phenotypic variance in an emerging global pest, our study highlights the importance of integrating urban ecology and invasion biology to understand how species spread and adapt in an increasingly human-dominated world.