An interdisciplinary approach to investigating an invasive insect pest: tracking, phenology, and genetics of the Queensland longhorn beetle, Acalolepta aesthetica (Cerambycidae: Lamiinae)

The Queensland longhorn beetle (QLB), Acalolepta aesthetica (Olliff), was first detected in the Puna District of Hawai'i Island in 2009 and has since been observed to attack high value specialty crops such as cacao (Theobroma cacao), breadfruit (Artocarpus altilis), and citrus (Citrus spp.), as well as the culturally important kukui, Aleurites moluccanus. Endemic to the Australian states of Queensland and New South Wales, QLB had no pest status before introduction into Hawai'i. To address the lack of basic biological data on QLB, we conducted four pilot experiments to support pest management efforts. These included sequencing the CO1 region of the mitochondrial genome, observing beetle behavior in both a laboratory wind tunnel during scotophase and in the field using harmonic radar tracking, and obtaining QLB spatial distribution data through a citizen science web-based reporting application hosted by ArcGIS Online. Our results place QLB in a phylogenetic context, which will allow the development of diagnostic tools to differentiate QLB from other longhorn beetles. Behavioral observations suggest that QLB are largely sedentary, move mostly by walking with rare flights, and spend most of their time in trees. Citizen science reports suggest QLB populations are highest in May-July, beetle locations are largely restricted to elevations under 500 m, and population expansions are mostly occurring along the coast. These data combined can be applied to pest management efforts for this important and invasive agricultural pest. Further, we hope this interdisciplinary approach can serve as a framework for research response efforts to invasive insects generally.