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Microbial symbionts are important for host organisms, and insects rely on the communities of microorganisms in their guts for several functions. Despite what we are starting to understand of their importance, gut microorganisms have been censused in relatively few insect species. In this study, we examined the types of culturable gut microorganisms in larvae of the catalpa sphinx, Ceratomia catalpae. The gut microbes of this caterpillar are of interest because it feeds only on catalpa trees, and sequesters catalpol from the plant for its own chemical defense. We cultured gut contents of 27 caterpillars from three populations on nutrient agar, and five distinct bacterial colony morphologies were recognized. Four of these morphologies were Gram-negative, and all five were cocci. Future studies with this caterpillar can explore the influence of these bacteria on its ability to feed on catalpa trees and sequester catalpol.


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18 Jul 2022
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  • Alternative title
    • Catalpa Sphinx Gut Microbes

  • Journal title
    • Papers & Publications

  • Volume
    • 4

  • Issue
    • 1

  • Date submitted

    18 July 2022

  • Keywords
  • Additional information
    • Acknowledgements:

      This research was supported by the University of North Georgia Biology Department and a Roberta Williams Teaching Initiative grant. Bill Lott provided assistance locating caterpillars on catalpa trees, and Stephanie Brandys and Brittany Veloce provided technical assistance. Bea Chapman and Brandon Mangum helped pour plates. Dr. James Diggs, Dr. Davison Sangweme, Dr. Jeanelle Morgan, Holly Munro, and Melissa Parks provided feedback to improve earlier drafts of this manuscript.

      Graduation Date:

      May 2017