Molecular Systematics of theChrysobothris femorataSpecies Group (Coleoptera: Buprestidae)

Abstract

The Chrysobothris femorata (Olivier) species group has expanded to 12 recognized species. Many of these species are sympatric, share larval host plants, and are difficult to reliably separate morphologically. This study investigated species limits and relationships among the recognized species occurring within the southeastern United States. Results are presented from phylogenetic analyses including several group members using sequences from cytochrome oxidase I (cox I) and arginine kinase (AK). Cox I analyses validated the monophyly of several Chrysobothris species outside of the C. femorata species group and recovered group members C. adelpha Harold, C. viridiceps Melsheimer, and C. wintu Wellso and Manley as monophyletic. However, cox I analyses yielded well supported nodes that rendered C. femorata Olivier, C. quadriimpressa Gory and Laporte, C. rugosiceps Melsheimer, and C. shawnee Wellso and Manley paraphyletic. AK sequences provided statistical support for monophyly of C. wintu and two well supported clades that rendered C. femorata and C. quadriimpressa paraphyletic. Imperfect taxonomy cannot totally account for this phenomenon. The observed pattern could be the result of ancestral polymorphism or lineage sorting, yet introgression of these C. femorata species group members is possible. Although observed results from these genes suggest potential taxonomic synonymization, such steps are premature. Greater understanding of interactions between group members as occurs within their overlapping geographies and host plants is needed. We suggest future molecular studies adopting a population genetics approach utilizing several nuclear genes or SNiPs acquired subsequent to a NextGen sequencing campaign.