Date of this Version
Published in American Entomologist, Winter 2021, pp. 26-29
The southern corn billbug is a univoltine insect most common in the Coastal Plains region of North Carolina, Virginia, Georgia, and South Carolina. However, this insect can also be found in the midwestern U.S. (Van Duyn and Wright 1999). Early in the growing season, the adults can be found feeding at the base of corn plants—typically with their head pointed downward (Fig. 1)—by inserting their beak into the base of the plant. They can kill or stunt seedlings or injure the developing leaves inside the plant, causing twisted leaves as they emerge or a series of small holes across the leaf. The degree of injury is influenced by the crop growth stage at the time of feeding. Larvae feed inside the stalk at the base of the plant (Fig. 2) and can reduce grain yield of infested plants.
As I started my graduate program and began a literature review, I found that there was very little recent biological literature on this insect. There were several extension bulletins and insecticide efficacy studies, but the most recent biological study was published by NCSU entomologist Z. P. Metcalf in 1917. Fortunately, Metcalf (1917) summarized much of the known biological research at that time, and I read it repeatedly to develop plans for my dissertation research. Today, Z. P. Metcalf is primarily known for his taxonomic work with Auchenorrhyncha (Dietz 2008). Many entomologists of his era worked in economic entomology, but also contributed research on the taxonomy and systematics of a particular group.