About Sphenophorus coesifrons Gyllenhal, 1838
Sphenophorus coesifrons, commonly known as the oblite billbug, is a species of beetle belonging to the family Dryophthoridae. It is found across North America, with a range extending from Maryland and Wisconsin in the north to the Gulf Coast and Arizona in the south. Adult oblite billbugs measure between roughly one quarter and five sixteenths of an inch in length. This species closely resembles the bluegrass billbug, and can be differentiated from it by its shorter, much thicker beak. As of 1924, the oblite billbug’s natural food source had not been identified, though it had been successfully reared on timothy in the midwestern U.S. states of Illinois and Michigan. The species was considered extremely damaging to corn crops along the Gulf Coast, and there are records of it destroying both first and second plantings of corn there. Female oblite billbugs have been observed laying eggs in late summer. In captivity, young oblite billbugs develop slowly, spending at least five months in the larval stage. Researchers expected that the oblite billbug’s life cycle is similar to that of the bluegrass billbug in the northern portion of its range. In the southern part of its range, eggs are laid in late summer or fall, and young insects overwinter in the larval, pupal, or adult stage.
