Method for Determining Age Structure of Adult Populations of the Lesser Cornstalk Borer (Lepidoptera: Pyralidae)

Abstract
Laboratory experiments were conducted to develop methods for determining age structure of Elasmopalpus lignosellus (Zeller) adults. Oöcyte development in the ovaries was used to establish five female classes:(1) no mature oöcytes; (2) ca. 25% of oöcytes mature; (3) ca. 50% of oöcytes mature; (4) >75% of oöcytes mature, >30 mature oöcytes; and (5) >75% of oöcytes mature, 75% depleted. At 26.7°C, 90.9% of the adult males in age classes 1, 2, and 3 were within the age intervals of ca. 0 to 4, 6 to 8, and 8 to 10 days of adult age, respectively. These physiologically based, female and male classification systems appear suitable for determining chronological age structure of feral populations.