Assistant Professor Louisiana State University Baton Rouge, Louisiana
Jewel Beetles (Coleoptera: Buprestidae; 15,000+ spp.) are well known for their iridescent coloration achieved through multi-layer stacks within the cuticle. However, there is one exceptional monophyletic tribe (Stigmoderini; 770+ spp.) within Buprestidae whose members exhibit vibrant yellow, orange, and red coloration through pigments of unknown chemical nature. Paired with a chemical defense toxin exclusive to Buprestidae, the coloration is presumed to be aposematic. Stigmoderini may be of Gondwanan origin, with a current disjunct distribution between the Australasian and Neotropical regions. This massive geographical splitting event has created variable environments and food sources, which may have caused an underlying shift in pigmentary synthesis and other biochemical processes. Understanding the diversification of unique pigments within a phylogenetic framework is necessary for revealing evolutionary patterns of pigment production and insect visual systems. This research will employ a combination of imaging, spectrometry, solubility, and chromatography to elucidate the pigment class(es) responsible for the atypical coloration in multiple genera of Stigmoderini which will then be combined with natural history data such as unique defense compounds, food preferences, and distribution. These relationships have the potential to assist in describing novel compounds and biochemical processes, utilize color as a taxonomic character, and investigate visual signaling and communication via using one atypical group that has undergone a significant evolutionary event. These data will be disseminated to currently developing color databases such as the Insect Color Database (ICDB; insectcolor.com) and PhotochemCAD (photochemcad.com) in order to inform future work.
