Early progress in establishing phylogenetic relationships between Chrysobothris species (Coleoptera: Buprestidae) using next generation and reduced-representation sequencing

The genus Chrysobothris (Coleoptera: Buprestidae) is distributed worldwide. About 134 Chrysobothris species occur in the US and Canada, of which several are secondary pests of economically important forest, nut, fruit, and landscape trees and shrubs. Species from the Chrysobothris femorata [Olivier] species group present morphologically similar characteristics. These complex members present serious challenges in nursery ornamental production attacking newly transplanted and established trees in landscapes. Our team’s research goals include employing next-generation molecular methods to assist in differentiating between adult members of 12 C. femorata species group taxa. We will also evaluate taxonomic relationships between other Chrysobothris species through comparison with closely related genera and other buprestid outgroup species. To achieve our goals, specimens of adult beetles representing different localities have been field collected or requested from private collectors and loaned from museum collections. Non-destructive DNA extraction is being optimized, allowing for the preservation of rare samples, especially from museum collection specimens. Beetles preserved in molecular grade ethanol yielded higher quality DNA than museum samples. Metagenomic data were obtained from each specimen using Illumina NGS genome sequencing. Orthologs (n=2689) were obtained using OrthoDB, including those from buprestid outgroups, Agrilus plannipennis, and used to capture orthologs from Chrysobothris specimens using aTRAM 2.0. Next, a maximum likelihood phylogenetic reconstruction will be generated from each sampled Chrysobothris species and representative outgroups using IQ-TREE. Overall, we anticipate the resulting phylogeny will provide informed species relationships between C. femorata group members that will guide accurate identification aiming to improve management practices in nursery production systems.