Natural History, Systematics, and Taxonomy of the Termite Assassin Bugs (Reduviidae: Salyavatinae), Host Associations, Salivary Protein Evolution and Bacterial Symbionts of Kissing Bugs (Reduviidae: Triatominae) and Evolutionary Analysis of Microbiota of Miroidea and Largidae
- Author(s): Gordon, Eric Robert Lucien;
- Advisor(s): Weirauch, Christiane;
- et al.
While modern methods have helped to advance our understanding of biodiversity, large gaps in our knowledge remain, particularly with respect to non-model and tropical lineages. My research interests focus on the integration of evolutionary studies with modern methods for study of the biology of the diverse Heteroptera. In my first chapter, I used taxon-specific primers to assay the gut contents of the putatively strictly termitophagous Salyavatinae corroborating that these cryptic tropical predators appear to feed only on members of the family Termitidae. Next, I conducted a comprehensive taxonomic revision of this group of 107 previously described species, describing 15 new species and revising its classification based on a combined morphological and molecular phylogeny of this group and its close relative Sphaeridopinae. In studying the blood-feeding Triatominae, I combed the extensive literature and recorded known sylvatic host associations and added several new sets of observations using PCR on triatomine gut contents with vertebrate specific primers. I assembled and annotated the transcriptomes of 20 species of reduvioid including Triatoma protracta, in an effort to infer the evolutionary forces that acted on proteins which have been heavily modified from their ancestral form in the blood-feeding Triatominae to and aid in hematophagy. I next assessed the microbial associates of a variety of different Triatominae finding that symbiont identity in these insects varies much more widely than has been previously assumed. I also surveyed the microbiomes of two other groups of Heteroptera, Largidae and Miroidea, finding that Largidae reacquire a specific group of Burkholderia symbionts from the environment every generation while the herbivorous members of Miroidea seem to be able to circumvent the nutrient limitations of their plant diet without a symbiotic association with bacteria. These studies illustrate the use of modern molecular methods and archival specimens to understand not just evolutionary history and species diversity of groups of understudied organisms but to infer aspects of their biology such as their biotic interactions with prey or symbiotic bacteria.